These were the postings that were originally featured on the publications page.

Waste Heat Recovery based power generation projects (WHR) in cement and lime plants are designed to capture



Sand particles derived from sandstone are delivered to the crusher hopper as rocks and boulders. Unlike mine crushing where the purpose is to reduce the size of the rocks to go into mills, the goal in frac sand operations is to



roof 3

Maintenance of cement storage silo roofs is challenging because the areas which may need repair are not readily visible and often structural damage is not noticed until a significant failure has occurred, the roof has settled, and the risk of 

Coal & Solid Fuels handling facilities

The most recent NFPA publication applicable to cement and lime plants, NFPA 652, mandates that every industrial facility handling solid fuels needs to complete a Dust Hazard Analysis (DHA) Study by August 2018, after which deadline plants risk becoming non-compliant.

Most cement and lime plants use coal and other solid fuels for their operation and therefore come under the purview of this mandate.

NFPA 652 “Standard on the Fundamentals of Combustible Dust” was created to include several older standards (NFPA-61, 68, 654) as a single go-to source for a systematic study of fire and explosion hazards and to develop mitigation measures.

The DHA Study promotes awareness of the following principles:

  • Fuel management controls.
  • Ignition source controls.
  • Restraining the spread of any combustion event.

It applies to equipment handling coal and other combustible dusts, including Dust Collectors, Bucket Elevators, Drag and Screw Conveyors, Pneumatic Conveying Systems, and Storage Bins and Silos.

DHA consists of 3 main steps to complete the analysis.

NFPA 652

Material and Process Identification:

  • Determine the characteristics of the dust with tests recommended in NFPA 652 to assess how combustible or explosible the dust is.

  • Identify the process areas where there exists potential combustibility and explosibility

Material and Process Hazard Analysis:

  • Evaluation of every process area that could promote fire and explosion hazards
  • For each identifies hazard area, the following aspects are analyzed:
    • Is the dust combustible in this segment?
    • Is the dust suspended in air?
    • Is the dust concentration such as to support a deflagration?
    • Is there an ignition source that could ignite the dust cloud present?
    • What hazard management controls are in place?

 Hazard Management Plan:

The Hazard Management Plan outlines the mitigation measures to be implemented for managing the suppression of deflagration and/or isolation of the source of deflagration. A written management system is developed for operating the facility to prevent or mitigate fires, deflagrations, and explosions from combustible particulates.

NFPA 652 outlines the topics to be covered in DHA and recommends a format to present the report.

PEC Consulting can help carry out a DHA Study for new or existing cement & lime plants and help the clients to develop a Hazard Management Plan.

This article was contributed by M. Dimah, Process Engineer for PEC Consulting, Mr. Dimah has a BS in Chemical Engineering from the University of Technology, Baghdad, Iraq, and a Master’s in Chemical Engineering from the Polytechnic University of Valencia, Valencia, Spain. He can be reached at 

Copyright © PENTA Engineering Corp. 10123 Corporate Square Dr, St Louis, MO 63132

View additional feature articles under PublicationsContact Us



There is a direct correlation between wasted product – which sometimes could be as high as 50% — and the process system efficiency at a frac sand manufacturing plant. The solution to minimize waste and increase profits lies in the optimization of plant product yield. Product yield is key to the economics of a plant’s operation. In a frac sand operation, the product yield is the relation between tons of sand grain liberated for sale and the actual tons of material mined. An analysis of the core sample will determine the product quantity per ton of material mined. The product yield in relation with the product in the mine should be in the neighborhood of 75%. In order to improve frac sand product yield, the following is a recommended course of action: 1. Verify that the main crusher is adequately sized for the vertical shaft impactors (VSI). This equipment tends to choke easily due to limitations at the feed point. The rock size exiting the crusher is important for the proper operation of the VSI. 2. VSIs should be properly sized for the amount of material feed. A small VSI will not de-cluster the frac sand completely, leaving sand in clusters. On the other hand, a large VSI will shatter the sand, damaging the sand particle shape. The correct size of a VSI should be determined by working closely with the VSI equipment supplier and running sample tests.


3. Most of the waste sand is normally dumped at the end of the crushing plant. The addition of a closed circuit at the end of the crushing plant to convey this waste product to a properly sized VSI can de-cluster additional sand grains and increase the product yield. This VSI works together with a screen to separate the final product. 4. The proper type of dry screens for final sizing sand grains is very important. High-angle screens are not recommended due to their inefficiency to screen 40+ mesh. Considerable good product can be wasted by the improper selection of screens in the dry plant. Low-angle screens with a gyratory reciprocating motion are more efficient in screening 40+ mesh particles. 5. The wet plant can be improved by additional attrition scrubbers in series if issues with acid solubility are present. This will contribute to further breaking up clusters of sand grains. HOW TO INCREASE FRAC SAND PRODUCT YIELD1 Producers may not realize how much product is being wasted by poor equipment selection. A particle size distribution test on the waste material is a good indicator of how much good product is being wasted.
The main contributor to this article was Pompeyo D. Ríos, Senior Mechanical Consultant, at PEC Consulting Group, St. Louis, Missouri.

View additional feature articles under PublicationsContact Us


Cement kilns offer very favorable conditions for incinerating waste fuels. High temperatures, long residence times, an oxidizing atmosphere and alkaline environment, ash absorption by clinker, and high thermal inertia all favor the use of Alternative Fuels in a cement kiln. There are many benefits tied to the use of alternative fuels in cement kilns; nonetheless, the challenges connected with their application require careful evaluation.

What are Alternative Fuels?

Alternative fuels are non-traditional fuels that have calorific value and can be used as substitutes for conventional fuels such as coal, petroleum coke, oil and natural gas in clinker manufacturing. Typically, alternative fuels are waste or byproducts from industrial, agricultural and other processes. Traditionally, they are managed through landfills, treatment or incineration and come in liquid or solid form. Liquid Alternative Fuels include solvents, mineral waste oil from used lubricants, vegetable oil and various organic liquids. Solid Waste Fuels come in different forms: used tires, pre-treated industrial and municipal waste, sewage sludge and domestic waste, Refuse Derived fuels (RDF) from pulp, paper and cardboard residues; non-recyclable plastics; Packaging and Textile industry, biomass such as animal feed, contaminated wood and wood chips, waste wood, rice husk, sawdust and sewage sludge, and used carpets.



Advantages of using Alternative Fuels

The main advantages of using Alternative Fuels in the Cement Industry are economic and environmental. Cement producers strive to reduce their production costs. Fuel accounts for 20 to 25% of the production cost of cement and one viable option is the use of alternative fuels at a much lower cost than conventional fossil fuels. The use of waste fuels reduces the carbon footprint that results from using fossil fuels and therefore the overall environmental impact of cement manufacturing operations. It also extends the supply of fossil fuels and is a safe way of absorbing waste which otherwise would present a waste disposal problem. The favorable conditions in a cement kiln completely destroy the organic constituents and the inorganic constituents combine with the raw materials in the kiln and exit the kiln as part of the cement clinker without generating solid residues. Free lime in cement clinker acts as a good absorbent of hazardous elements. The cement kiln therefore is a natural incinerator that has a safe thermal environment for the use of alternative fuels. Use of alternative fuels in the cement kilns hence helps resolve air pollution problems by eliminating additional emissions which would have resulted from the incinerators while destroying the wastes.

Challenges & Limitations

Consistency of the chemistry and continuous availability are two major considerations in the use of Alternative Fuels. All alternative and derived fuels are generated at sources outside the control of cement manufacturers. Therefore, there are always some limitations on the availability of consistent quality alternative fuels in adequate quantities. The suitability of Alternative Fuels for use in the cement manufacturing process, effects on plant operation, product and environment need to be studied and established before the alternative fuel is selected. The composition of the Alternative Fuel and its availability will determine the extent to which it can be used. 2


Invariably, all alternative fuels require pretreatment prior to introducing them in the kiln or precalciner. Processing an Alternative Fuel may involve significant capital investment. Modifications to the existing plant equipment and the creation of new infrastructure for the intended use of the alternative fuel will be required. For instance, feeding whole tires requires a complex system and considerable space for implementation. In addition, converting from the use of conventional fuels to alternative fuels will call for adjustments to operating parameters, raw mix design, etc.

  • Safety

Safety aspects related to alternative fuels depend on the type of fuel. Safety related issues mainly include handling and storage of fuels that emanate odors or are hazardous wastes. The selection of appropriate feeding points depending on the characteristics of the alternative fuel is also a safety consideration.

  • Emissions and Environmental considerations

The use of hazardous waste as an alternative fuel in cement kilns is regulated by local environmental regulations for the incineration of waste. Emissions of air polluting compounds need to be addressed while considering use of alternative fuels in the cement manufacturing process. Emissions of Carbon monoxide, Sulphur dioxide, Nitrogen oxides, Hydrogen chloride, heavy metals such as mercury, lead and cadmium, Dioxins and Furans are major concerns. They are to be controlled below prevailing emission norms irrespective of the fact that whether the manufacturing process uses traditional fuels or alternative fuels. However, this can be achieved with controlled inputs, optimized and stable operation and if required with the installation of a kiln gas by-pass system. Cement kilns fired with conventional fossil fuel or with alternative fuels of all types can meet stipulated emission limit.

  • What PEC Consulting can do?

Evaluate the suitability of Alternative Fuels. Evaluate the impact on the environment and develop concepts for mitigation measures. Recommend modifications to the existing kiln system for adaptation to the Alternative Fuel. Develop the CapEx and arrangement drawings. If the project is viable, PEC Consulting can subsequently develop the engineering for handling, processing and firing of the fuels into the kiln.



The main contributor to this article was Jagrut Upadhyay, Senior Process Consultant at PEC Consulting Group.  Jagrut has a Bachelor of Science in Chemical Engineering, D.D. Institute of Technology, Gujarat University, India

View additional feature articles under PublicationsContact Us


Several energy efficient options for cement grinding are available today such as vertical roller mills, roller presses (typically in combination with a ball mill), and clinker pre-grinders with ball mills. Ball mills have been the traditional method of comminution in the mineral processing industries and continue to operate with old generation classifiers, their maintenance sometimes neglected. This in combination with an inefficient operation translates into high energy consumption and low production. The consumption of energy by the cement grinding operation amounts to one third of the total electrical energy used for the production of cement. The optimization of this process would yield substantial benefits in terms of energy savings and capacity increase.

Optimization of the Cement Ball Mill Operation

Optimization addresses the grinding process, maintenance and product quality. The objective is to achieve a more efficient operation and increase the production rate as well as improve the run factor. Consistent quality and maximum output with lower specific power consumption results in lower operating costs per unit of production. Optimization can also reduce the cost of liners and grinding media. The cost of optimization is minimal since inspecting the mill and the resulting modifications — such as re-grading the grinding media or moving the diaphragm are labor elements that can be handled by the plant’s maintenance crew. Upgrading the classifier and baghouse involves capital expenditure with a high benefit to cost ratio. Optimization is especially important when multiple products are being produced.

Operation and Elements of a Closed Circuit Ball Mill System

Cement ball mills typically have two grinding chambers. The first chamber is filled with larger diameter grinding media and lined with lifting liners. The first chamber coarse-grinds the feed material and prepares it for the second chamber. The second chamber is the fine grinding chamber. It is lined with classifying-type mill shell liners and provided with finer ball charge. Classifying liners ensure that the ball charge is segregated along the length of the chamber keeping larger grinding media at the beginning of the compartment and smaller media towards the end of the chamber. An intermediate partition, called the central diaphragm, separates the coarse and fine grinding chambers. The purpose of the central diaphragm is to retain the grinding media in their respective chambers, provide adequate opening for the airflow and, in some special types, regulate the feed to the second compartment. The mill is equipped with a discharge diaphragm at the end. This diaphragm retains the grinding media in the second chamber and allows the discharge of finely ground material.


Closed Circuit Ball Mill System

Clinker, Gypsum and other desired additives are fed to the ball mill in specific proportions based on the quality requirement. Feed material is ground in the ball mill, discharged and fed to a classifier with the help of a bucket elevator for classification of the ground cement into two streams – coarse and fines. The coarse fraction is sent back to the mill and the fines are collected in cyclones and / or a baghouse as finished product. The mill is ventilated by an induction fan. The air required for classification is provided by another fan. The fans pull the gases through independent baghouses which clean the vent air and return the cement dust to the system.

Auditing the Operation

The audit of a closed circuit grinding system focuses on feed material characteristics, grinding progress in the mill, mill ventilation, classification and controls. Internal inspection of the mill can reveal a lot of important and vital information about the performance of the grinding system such as the separator’s behavior, influence of grinding media and the mill ventilation. Circuit sample analysis and mill chambers sample analysis indicates performance of the separator and progress of the grinding process along the length of the mill. The separator is expected to perform in a way that a minimum of the fines is carried in the coarse reject fraction and sent to the mill for regrinding. The separator’s efficiency is determined by drawing a Tromp curve based on particle size distribution analysis. The separator’s performance can be improved by changing the adjustments or replacing worn components. The operational controls are also reviewed for optimized mill operation. Every element of a closed circuit ball mill system is evaluated independently to assess its influence on the system. Figure 1 below is a typical example of inefficient grinding indicated by the analysis of longitudinal samples taken after a crash stop of the mill.


Fig 1. Analysis of longitudinal samples

The graphical analysis in Figure 1 represents the progress of the grinding process along the length of the mill. In a correct operation the residue will be high initially, falling gradually as grinding progresses, which is not the case in the above graph. Compare this with the milling progress as presented in Figure 2 after optimization. The following picture shows the condition of the grinding media and the material in one of the grinding chambers of the mill. These observations provide a clear idea of internal conditions — such as a clogged diaphragm or incorrect material level — and present the potential steps for optimization.


Condition in one of the grinding chambers of the mill

Results of Optimization

The graphical analysis presented in Figure 2 represents progress of grinding along the length of the mill after optimizing the grinding process. Desired progress of grinding is clearly visible in the graphs.


Fig 2. Analysis of longitudinal samples.

Use of suitable grinding aids also is recommended to improve grinding. However, it is important to mention that grinding aids should not be considered as optimization tools. It is recommended that all operational and process deficiencies be eliminated and that the system be optimized before considering use of a grinding aid to further improve the process. Results of the optimization can be measured by multiple parameters such as separator efficiency, specific power consumption, system throughput, and wear rate of grinding media and liners. Changing the separator to a high efficiency type brings about better residue value (on 45 micron) for the same Blaine. Alternatively, the cement can be ground to a lower Blaine with the same residue, which determines the strength of cement. In most cases the layout permits replacing the separator to a high efficiency type. An evaluation of the grinding system and operation includes meaningful and critical inspection of all equipment, components and the process parameters by experts. PEC Consulting can help carry out detailed evaluation of existing grinding systems and their operation and recommend steps for improving performance.

The main contributor to this article was Jagrut Upadhyay, Senior Process Consultant at PEC Consulting Group.  Jagrut has a Bachelor of Science in Chemical Engineering, D.D. Institute of Technology, Gujarat University, India

View additional feature articles under PublicationsContact Us


General Arrangement drawings (GAs) should be prepared in sufficient detail to show the location of process equipment, material handling and storage, power distribution, utilities, floor elevations, column lines, maintenance access, stair locations, and overall outline of the structures. GAs are reviewed and approved periodically in their development by all stake holders.


Fig 1. Cement Plant Layout

Prior to starting work on general arrangement drawings, the Owner agrees to a set of codes and design criteria that will govern the design of the new plant. Another key component is a survey of the area, which is especially important for a Brownfield plant expansion.

The GA review should start in the conceptual planning stages to assure an optimum and economical equipment arrangement.

Stairs provide the primary access to floors, platforms, walkways and equipment. Equipment located more than 2 meters above floor level should be provided with stairs and a platform for access. Ladders are not used except where space is limited. It is also acceptable to use a ladder to access nuisance dust filters or some instruments to which stair access is not practical.

Layouts should provide a minimum 1 meter clearance for walkway areas and maintenance access around equipment. Some equipment requires additional space for maintenance; i.e., removal of components. Standard mandatory height clearance in access platforms need to be at least 2.2 meters minimum in all areas.


Fig 2. Belt Conveyor Arrangement with Platform Accessible by Stairs

The optimization of conveying equipment to minimize its length needs to be done without compromising design parameters. Several factors that should be reviewed include the air gravity conveyor’s slope angle, the conveyor’s load angle, speed and radius, chute angles, apron feeder’s load angles, etc.


Fig 3. Belt Conveyor Loading, Transport, and Discharge Arrangement

Various configurations of material transfer chutes are used in plant design. Considerations for chute designs should include the type and characteristics of the material handled such as particle size, moisture content, flow characteristics, and abrasiveness. Chute slope angles are specified in the Design Criteria and shall be steep enough for material to flow by gravity. Chutes having long vertical drops shall be “laddered” down in order to control momentum.

Overhead hoist beams for equipment maintenance should be provided when the equipment is not accessible by mobile hoists or when the equipment cannot be handled manually. Maximum hoist loads must be indicated on the GAs. For example, equipment that should be provided with overhead hoists includes crushers, process fans, clinker breakers, bucket elevators, pumps, air compressors, equipment drives, etc. For large equipment like roller mills, a bridge crane should be provided.


Fig 4. Hoist to Service Bucket Elevator and Belt Conveyor Drives

Dust suppression systems should be considered where dust is generated. Proper dust suppression systems are normally used at emission points followed by adequate filter sizing, and material discharge. GAs are reviewed to ensure that dust suppression/collection parameters in the Design Criteria are being followed.


Fig 5. Dust Control System at Material Transfer

Special attention shall be provided to explosion vents. Design shall ensure that no structure or walkway is close to the expansion wave from an explosion.

The above directions are general guidelines, but revisions that have a greater scope may apply depending on regulations and the Owner’s specific requirements.

The general arrangement review ensures an optimum design and an efficient and cost-effective equipment layout, adequate accessibility to install and service equipment, and a safe and dust-free workplace.

The main contributor to this article was Pompeyo D. Ríos, Senior Consultant & Project Manager – at PEC Consulting Group. Mr. Ríos has a BS in Mechanical Engineering from the Universidad Metropolitana, Caracas, Venezuela, and a Master’s in Business Administration, Finance and Accounting from Regis University, Denver, CO

View additional feature articles under PublicationsContact Us


The Cement Industry is under increasing pressure to become more profitable.  Globally, there is overcapacity of production. To be competitive, Production Units need to optimize operations to the maximum possible level so as to lower overall operating costs without having to make major capital investments. The cost of production depends on several factors, such as location, infrastructure, raw materials and labor costs, type of packaging and, most importantly, the cost of fuel and electricity. Average distribution of production costs can be represented as shown in the following example:


While most factors are location specific, the factor that represents the highest potential for optimization and cost reduction is the actual consumption of fuel and electricity which, in the example above, constitutes 33% of operating costs. Next in line, is the cost of labor and maintenance. Optimizing the operation with the aim of lowering fuel and electricity consumption presents the least expensive way to realize savings. In most cases, this does not involve major investments. Even small unitary savings result in significant profits because of production volume of cement manufacturing operations.  


A modern dry process cement plant, with efficient configuration of the grinding and pyroprocessing systems typically consumes less than 700 kcal/kg-cl thermal energy and 100 kWh/mt of electrical energy. Cement plants are designed based on the raw materials and fuel samples tested by the equipment supplier. The equipment supplier guarantees are also based on the test results and under perfect operating conditions. In practice, the quality of the actual raw materials and coal varies. If the operating strategy is not adjusted accordingly, it will result in sub-optimal operations and higher operating costs. This is a problem even new plants need to address. Older plants have less efficient systems, which compounded with operational and maintenance inadequacies result in higher energy consumption. All plants, new and old thus have a potential for optimization.  


An energy audit is required to evaluate the operation of a cement plant against the benchmark of similar well-managed plants. After a detailed evaluation of the current raw materials and operating parameters, benchmarks are adjusted to correspond to the specific conditions of the plant. Raw materials are a major variable in this evaluation. Raw mill grindability, for instance, can affect the power consumption of the raw mill section considerably. Based on the results of the evaluation, recommendations are made to optimize the operation in either one, two or three levels: Level 1: Optimize the operation with no or very little investment by adjusting the operational strategy and attending to maintenance areas Level 2: Improve operation through minor investments and staff training Level 3: Incur into bigger investments; however, with payback in a short time. Once improvement potentials are identified, the management can determine based on cost benefits, the program they want to follow. In most cases, there is enough justification for undertaking Levels 1 and 2.  


 1. Historic Evaluation

The plant operational and stoppage data is collected over the past one or two years. The reasons for stoppages are analyzed in terms of category (mechanical/electrical/ instrumentation/other), duration and frequency of stoppage, etc. in order to isolate the most detrimental causes for stoppages.

The plant performance is also analyzed department-wise. Often, a department’s best performance does not necessarily occur when the plant as a whole performed the best. If we choose the best performance times of each department and make them occur at the same time, the plant performance will show a considerably high level of efficiency. Attempts can be made to make them happen at the same time, which is not an unrealistic target as the departments have indeed performed at that level in the past.

2. Thermal Energy

A major part of thermal energy relates to the Pyroprocessing system. For a 1 million mt/year clinker production, savings of 10 kcal/kg-cl would result in yearly savings of approximately $185,000, assuming a heat value of 6500 kcal/kg and coal price of USD120/t.


Apart from the savings at the same production levels, the significant advantage in most cases is that this reduction in heat consumption could be utilized for increasing production later when the demand for cement increases by utilizing the spare capacity of the fan created during optimization.

The audit is done by calculating the heat and mass balance of the Pyroprocessing system. The most benefit generally comes from optimizing the cooler operation; cooler loss is thus minimized, which is one of the main reasons for low heat consumption in a modern plant.

In-leakage in the pyro system also contributes to thermal loss, the extent depending upon where the leakage occurs. This is often corrected by maintenance procedures.

Operational strategies are also optimized to improve thermal efficiency.

Raw materials chemistry is another factor that is optimized to improve the efficiency within the possible limits of raw materials availability.

At each stage of adjustment, heat and mass balance is carried out to record the improvements.

3. Electrical Energy

Large fans and Mill drives are the major consumers of electrical energy in a cement plant.

The fan power in the Pyroprocessing system is also linked to the thermal efficiency of the system. Cooler optimization, arresting In-leakage in the preheater, and maintenance of the correct oxygen level are part of the plant audit.

The fans in the grinding systems depend on the system configuration, which cannot be altered in an existing plant. However, the operation itself can be optimized for reducing the airflow and improving production, which contribute to the kWh/t of fans.

The mills are large consumers of power as well. In the case of ball mills, optimization of the mill charge helps to minimize the power consumption of the mills. In the case of vertical roller mills, inspection of the mill internals and adjustments in the operation will bring about an improvement in the energy consumption and for production increase.

4. Analysis

The data collected is analyzed and the findings discussed with the plant operating personnel and plant management.

As a first level, a field visit by an experienced consultant will itself reveal several potential areas for improvement, such as leakages, damaged or nonfunctioning sluice valves in a preheater, gaps in the cooler grates, etc., most of which can be rectified by plant maintenance t without additional investment. This level also includes process adjustments, such as optimizing the oxygen levels, raw mix chemistry, burner, etc.

As a second level, minor investments in the form of replacement of worn or damaged parts, minor duct modifications, insulation, etc. will contribute to improvement in the economy of operations.

In the third category, higher levels of investment will be considered. Examples are changing preheater cyclones to low pressure type, changing to mechanical transport, additional of new instrumentation and control systems.

The identified steps for improvement are classified according to the investment requirements and the recommendations presented to the cement plant.


The cost-benefit analysis of the recommended steps should assist the cement plant strategize the implementation plan. Since the improvements are to be monitored all the way to determine the next steps, a constant involvement by PEC Consulting will help the plant on this effort. Generally, the plant personnel are deeply involved in the day–to-day running of the plant and have very little time to do a systematic evaluation of the plant operation. PEC Consulting can contribute by working with the plant personnel and carrying out a scientific study of the operations. A combination of theoretical calculations and practical observations and feedback from the plant personnel would collectively provide a valuable input to the clients for achieving better performance of the plant, lower energy bills and a potential for higher production when the demand for cement increases.

The main contributor to this Article was Narayana (Jay) Jayaraman, Senior Process Consultant and Technical Director at PEC Consulting Group in St. Louis, Missouri, USA. He may be reached at

View additional feature articles under PublicationsContact Us

A Process Hazard Analysis (PHA) is a key element of a Process Safety Management (PSM) program. It analyzes potential risks to personnel operating in an industrial environment. A PHA is a thorough detailed systematic approach to finding potential hazards in an industrial plant. It includes an analysis of the equipment, instrumentation, utilities, human actions, and external factors which could be potential hazards. One of the techniques of a PHA used to identify hazards and operability problems is the HAZOP (Hazard and Operability) study which can be performed on both a new or operating coal grinding and firing system. This article describes activities and elements involved in a HAZOP study of a coal grinding and firing system.


DSC05803The handling, preparation, storage, conveying and firing of ground solid fuel have inherent operating risks. Various qualities of coal are used as fuel. Due to the combustible properties of coal in general, safe handling is important during the entire process.

Accidents are mainly caused by the unintended release of energy caused by fire and explosion. A HAZOP study identifies situations where such release of energy may occur. It also identifies and estimates the potential severity of damage and recommends mitigation measures.

A HAZOP study of a typical operating Coal Grinding and Firing System encompasses the following areas:
  • Fuel handling and storage – Raw coal receiving, storage and handling.
  • Fuel preparation – Raw coal grinding.
  • Fuel conveying – Fine coal storage and conveying for an indirect firing system.
  • Fuel conveying – Fine coal conveying for a direct firing system.


A HAZOP study is generally performed using a comprehensive and widely used methodology in the industry, known as “What –If”. The technique is usually performed by a team of 3 or 4 experts. By using relevant documents, process knowledge and experience, the team develops “What-If” questions around all possible deviations, upset process conditions, equipment failures and potential human errors. Potential hazards, operational problems and design faults are thus identified. The team evaluates the consequences of each deviation and, depending on what safeguards are available in the present system, decides upon recommendations or actions for preventing such occurrences. The HAZOP Study of the Coal Grinding and Firing Systems addresses the following aspects:
  • The hazards of the coal grinding and firing process,
  • Engineering and administrative controls applicable to the hazards and their interrelationships,
  • Detection methods (Hydrocarbon detectors & gas analyzers) and continuous process monitoring,
  • Consequences of failure of engineering and administrative controls,
  • Human factors affecting the operation,
  • A qualitative evaluation of safety and health effects of failure of controls on employees,
  • The identification of any previous incident which had a potential for catastrophic consequences.


The following documents will be required for a HAZOP study:
  • Layout and G A drawings
  • Equipment lists
  • Process flow sheets and Process and Instrument Diagrams
  • List of Process control loops and Process and Safety Interlocks
  • List of Instrumentation and Alarms and Process variables with all limits
  • Operating procedures and work instructions for various modes of operation
  • Maintenance procedures and work instructions
  • Documentation on all auxiliary systems and Fire hydrant system
  • Raw Coal and Fine Coal analysis
  • Method to control bypassing the Interlocks and Alarms
  • Hazardous Area Classification


A HAZOP study is performed by a team whose members are process and maintenance engineers with specific knowledge in the operation and maintenance of coal grinding and firing processes. At least one member of the team must be knowledgeable in the specific process hazard analysis. Operation and maintenance engineers as well as coal mill operators participate in structured brainstorming to look for deviations from the design performance.


A HAZOP study identifies potential deviations which had not been experienced in the coal grinding and firing system. The ultimate aim of a HAZOP study is to achieve the following:
  • ensure that the coal grinding and firing system can be started, operated and shut down safely,
  • recommend appropriate changes to the process design or its operation that increase safety or enhance operability,
  • consider existing safety interfaces with operation software including installations such as the Coal mill baghouse, fine coal storage and dosing system, fuel firing systems, inertization systems, etc.,
  • derive the recommendations and actions to eliminate potential occurrences identified as risks.
A HAZOP analysis is required whenever there have been modifications/changes to the equipment, operation and maintenance procedures, operating parameters, environmental conditions; and in the case of incidents or near misses. Therefore, a HAZOP analysis also provides an opportunity to develop a system to manage Changes effectively.


The HAZOP Study Report provides comprehensive results compiled in specific formats and clearly lists the actions to be taken by the plant management. Table 1 is a typical analysis format used to record the findings.

HAZOP table1

The main contributor to this Article was Jagrut Upadhyay, Senior Process Consultant at PEC Consulting Group in St. Louis.  Jagrut has a Bachelor of Science Degree in Chemical Engineering, from the D.D. Institute of Technology, Gujarat University, India

View additional feature articles under PublicationsContact Us

Happy Holidays

Contact Us » icon-contact2x

2015 has been a very successful year of business growth and development for our consulting group. We are thankful to our Clients for the trust bestowed on our services and being receptive to our ideas and recommendations. We are also appreciative of our valuable staff which through teamwork and dedication has again provided our customers with the high-quality product they expect from us.

During 2015, PEC Consulting was awarded various types of consulting assignments, among them Scoping Studies which proved project viability and went on to the feasibility phase. We executed assignments for many industries, including coal, metal mining, cement, fracking sand, and lime during this year.

We make use of this occasion to wish our customers, partners, consultants and employees the happiest of Holidays and a Prosperous New Year.




For the implementation of a new Cement Import Terminal, the best practice begins with hiring an experienced consultant to perform a Feasibility Study.  As a preliminary step, prior to beginning the feasibility study, a scoping study should be executed.  The Scoping Study will examine the fundamental aspects to the project.

The Scoping Study should focus on:

  • Preliminary Communications with Port Authority and Government Agencies
  • Permitting
  • Preliminary FOB Cement FOB Pricing for Region and Availability
  • Examination of Possible Site/s location/s
  • Preliminary Project CapEx, OpEx, Simple Economic Analysis
  • Preliminary Conceptual Designs
  • Preliminary Examination of Infrastructure and Logistics
  • Social and Environmental hurdles 
  • Market Study (if applicable)

The Feasibility will advance elements of the Scoping Study and will additionally cover:

  • Source pricing to Cement Supply and Transport 
  • Obtaining bids from Vendors and Contractors
  • Develop Design Criteria, Basic Layouts and Specifications for the Port Facility terminal
  • Project Schedule and Execution Strategy
  • Risk Assessment
  • ROI

The primary role of the Consultant will be to gather and analyze the data for the Study, while the Owner  takes an active role in advancing communications with all relevant stakeholders and consultants, which may include  the following:

  • Port Authority
  • Local Government Agencies
  • Consultants
  • Legal Counsel
  • Vendors/Contractors
  • Cement Suppliers
  • Transport Companies
  • Unions/Stevedores


In order to optimize operations to improve margins per ton of cement, it’s important to understand all the variables.  These variables need to be examined and weighed against each other to determine the best facility type, size and level of automation.  The variables considered include:

  • Cement Shipment Size
  • Product Turnover
  • Sizing of Unloading Equipment
  • Storage Size Requirements
  • Facility lot Size and Berth Capabilities
  • Port Ship Size Limitations
  • Port Fees
  • Maintaining Separation of Deliveries
  • CapEx, OpEx, and Desired Return on Investment
  • Automation (CapEx) vs. Labor Costs (OpEx)
  • Environmental Requirements
  • Zoning Restrictions
  • Any other variable that needs to be considered for the site

Cement Import Terminals Options


 Flat Storage Option

The Cement Flat Storage provides an excellent solution for a low-CapEx storage. Certain factors need to be considered and weighed to determine if a Flat Storage is desirable: 1Figure 1: Typical Flat Cement Storage with Front-End Loader Reclaim (Image courtesy of Cement Distribution Consultants)Figure 2: System (Image courtesy of Siwertell)

  • Labor costs
  • Lease costs
  • Availability of sufficient land area
  • Lower CapEx is a requirement for project approval
  • Compartmentalizing
  • Flexibility with expanding capacity

Reclaim for Flat storage can be handled in several ways.  If labor costs are low, it would be preferable to have front loaders that feed a hopper and bucket elevator to fill the truck loadout bins.  In locations where labor costs are extremely high, there may be value in the installation of fluidized flooring.


Dome Storage Option

Domes provide a good solution for a fully automated operation.  There are various configurations that can be designed for specific operational needs.  The capital expenditure is expected to be higher than that of a flat storage, but there are benefits of a Dome Storage  such as:Figure 3: Typical Dome Storage System (Image courtesy of Cement Distribution Consultants)Figure 4: Typical Cement Dome Storage, (photo courtesy of HDOT)

  • Large live storage capacity
  • Full Automation
  • Reduced labor costs
  • Smaller footprint

In cases where multiple products are required or deliveries need to be kept separate, multiple domes or combination of dome and silos would need to be considered.


Silo Storage Option

Figure 5: Cement Silo Storage with Truck and Rail Disbursing (photo courtesy of, a silo storage is a preferred method for dispersing product to local markets that cannot be accessed by large bulk carriers.  Silo storages are only seen along rivers and lakes where small 5-10kton barges are used for transporting from a production plant.  One of the benefits of this type of storage is that it takes up a very small footprint; however, the capital cost to build per ton of storage capacity is the highest.

Floating Storage

Converting an older bulk carrier into a floating storage is a low-cost storage option, however not all ports are warm to this concept. The ship unloader can be mounted on rails on the vessel deck and used to unload from the incoming vessel as well as to withdraw from the floating storage to the truck-loading bins on shore. Either a Handymax or Supramax ship could be converted and designed for a storage capacity of 40,000-50,000 metric tons in 5 or 6 compartments (holds). This is by far the most economical option. It’s important to begin early discussions with the local port authorities to discuss this option before making any investment. A permanent berthing space would need to be obtained from the Port Authority within a reasonable distance (300 m or less) from the truck loading bins on shore.

Figure 6: Floating Storage Example (In Use)Figure 7: Floating Pipeline to Truck Loading Bins


Unloading equipment

Figure 8: Barge Mounted Unloader (Photo courtesy of FLSmidth)Bulk carriers can be unloaded through various methods.  The two preferred methods are by either screw or pneumatic conveying.  Typically, screw to belt is common on docksides where fixed equipment is allowed which represents an overall lower Operation cost to unloading.  Pneumatic is preferred in cases where the dock face is considered to be shared and unloaders, whether mobile or barge mounted, must be moved after unloading operations have been completed.

Some of the major considerations for ship unloader selection and design are:Figure 9: Floating Storage Rail Mounted Unloader (Photo courtesy of VAN AALST Bulk Handling)

  • Reach requirements
  • Rate of unloading
  • Distance of transport
  • Mobility needs

Ship unloading manufacturers can create custom solutions, however, it is important to understand that keeping the design as standard as possible offers cost savings to the project.

Figure 10: Dockside Screw Rail Mounted Unloader (photo courtesy of Siwertell)Figure 11: Pnuematic Rail Mounted Unloader (photo courtesy of FLSmidth)

The main contributor to this article was Christian A. Benavides, Construction Technical Consultant at PEC Consulting Group LLC, St. Louis, Missouri, U.S.A.

View additional feature articles under PublicationsContact Us

When done systematically and in coordination with the plant process, the commissioning process of a plant results in a fully functional  and lucrative operation

This article describes elemental pre-commissioning and commissioning activities for achieving the delivery of a quality project and the smooth start-up of a new plant.

The Commissioning Team must verify proper erection and oversee testing of each piece of equipment according to equipment manual and specifications, and check-out procedures developed for the project.  Incomplete checks will result in frequent stoppages and will eventually lead to poor plant availability, delayed commissioning, and over run of the project cost.

For example, unflushed compressed air lines might cause failures of pneumatically operated instruments and equipment. Likewise, unflushed cooling water lines could adversely affect the equipment and the cooling water system.

The role of commissioning involves:

A. Structuring the commissioning teams B. Pre-commissioning activities C. Commissioning and performance testing

A. Team Structuring

The following teams are responsible for working together in order to achieve a safe, smooth and trouble-free start-up.  Schedules need to be programmed to allow for a 24/7 uninterrupted operation.

1.OEM’s team

Plant management should have a team of Original Equipment Manufacturers’ (OEM) commissioning engineers ready at the plant prior to no-load tests to ensure that sequential interlocking, and all safety instruments and control systems are in place.

2.Owner’s Erection and Commissioning Team

The Owner’s team should be composed of the plant’s experienced Process, Mechanical, Electrical / Instrumentation engineers as well as Central Control Room operators.

The Owner’s team should be supported by Senior Consultants from the Consulting Firm supporting the commissioning and start-up of the plant.

B. Pre commissioning activities

  1. Analyses of raw materials and fuel
  2. Procurement of critical commissioning spares
  3. Ensure availability of all documentation on equipment and systems
  4. Mechanical and Electrical check-out according to procedures
  5. Construction punch list completion
  6. Cleaning of utility lines
  7. Complete preliminary check
  8. Testing of Electrical and Instrument controls
  9. Verification of “Site Start & Stop” and “CCR Start & Stop”
  10. Calibration and operation of dampers and control valves
  11. Calibration of weighing equipment
  12. Group trials of equipment
  13. Procurement of Portable Measuring Instruments. (Process parameters measuring Instruments)
  14. Ensuring the laboratory test equipment is operational
 Equipment trial runs should be done continuously for a few hours; the equipment is then inspected and corrected, if required.

C.   Commissioning and Performance Testing

General Steps involved in commissioning:

  1. Ensure good health of motors and electrical devices
  2. Group sequence starts for each process area
  3. Follow the correct heating cycle for the pyroprocessing equipment
  4. Plant Start-up on load
  5. Plant operation under guidance from OEM’s Commissioning Engineers.
  6. Tune PIDs and control loops
  7. Record of process parameters in log sheets
  8. Manage stoppage and re-starts of each processing areas
  9. Review and understand the following documents with respect to system, product quality and performance guarantee:
    • Suppliers’ Instruction Manuals;
    • Equipment Specification List;
    • Flow Sheets;
    • Raw Material Analysis;
    • Instrumentation ranges;
    • Instrumentation Alarm / Recorder / Controller scheme;
    • Start – Stop – Operation – Safety Interlock logics;
    • Process Parameters to be maintained for optimum operation;
    • Refractory Drying schedule (from refractory supplier).

10. The joint review by the OEMs’, Owner’s, and Consultant’s teams also includes commissioning protocols, sequences, control scheme and interlocks.

Commissioning and performance testing

After the erection team clears the equipment and no – load trials with a certificate of completion, the Commissioning team will take over the plant for commissioning. Commissioning is a controlled activity well-coordinated with the mechanical, electrical and quality control (laboratory) teams. All the guaranteed parameters are measured during the same commissioning trial. Energy consumption is measured at rated production levels according to the agreed test procedures with the OEMs.

Commissioning and performance testing establishes if the plant meets the production guaranteed values. It also serves as a release of the OEMs’ obligations with respect to meeting their guarantees. The plant is handed over to the production team to start operations once a Commissioning and Performance Certificate is issued.

The main contributor to this Article was Jagrut Upadhyay, Process Consultant at PEC Consulting Group in St. Louis.  Jagrut has a Bachelor of Science Degree in Chemical Engineering, from the D.D. Institute of Technology, Gujarat University, India

View additional feature articles under PublicationsContact Us

Most rotary kilns use solid fuels as the main heat source to produce cement clinker.

A training program should be developed and extensive training for coal mill system operators provided on a regular basis. Safety considerations, such as the prevention of fire or explosion are of utmost importance as is the knowledge of how to proceed under normal conditions. The training program should include the development of an operating manual which should be updated with new procedures as situations occur.


Durkee Coal Mill 2


Solid Coal Unloading, Storage, and Reclaiming Areas

A major hazard associated with coal handling facilities is the possible formation of an explosive atmosphere originating from accumulation of methane and coal dust especially in enclosed areas or tunnels such as rail unloading facilities. Walls should be washed down frequently to prevent dust accumulation, and welding or electrical repair work should not be conducted in an enclosed area during unloading operations or if methane or coal dust is present. Smoking, open flames, and other potential ignition sources should be prohibited in any areas in which coal is being handled or processed.

Fires that start around the edges of coal storage piles should be removed with a front end loader, spread in a location away from the coal storage area, and allowed to cool. Water should NOT be sprayed on a smoldering coal pile. The degree of wetness in a coal storage pile is known to influence spontaneous heating.

Belt magnets and metal detectors on coal belts must always be operating properly. Pieces of metal can cause sparks or become overheated which can ignite a fire or initiate an explosion. Scrap metal in a coal mill is particularly dangerous during mill shut down or start up.

Coal Mill Operation

Fires or explosions most likely occur during startup and shutdown of a coal mill system. If a small amount of coal remains in the mill after it is shut down, it slowly increases in temperature. If the pulverized coal undergoes spontaneous heating and the coal mill is restarted with hot embers present, an explosion or fire is possible. Although this does not happen often, the chances increase when a coal mill is frequently shut down and then restarted.

A coal mill system that goes down, particularly under load, must be treated with extreme caution. In several cases, fires or explosions have occurred when an employee opened an inspection door. Air admitted to the system allows oxygen to reach a smoldering pile of pulverized coal that then ignites explosively. Also, an inrush of air may create a pulverized coal dust cloud that explodes.

Accumulations of Pulverized Coal Dust

All leaks, spills, and any accumulations of coal or coke dust must be cleaned up promptly around coal mill grinding and firing systems because of the potential for spontaneous combustion. Small piles or layers of coal or coke dust may spontaneously heat and start a fire.

Coal dust spills or leaks must be cleaned up or repaired as soon as it can be safely done. A potentially serious problem exists if coal dust is allowed to accumulate inside a building or enclosure, for example around an unloading facility or because of a leaking coal conveying line. If large accumulations of dust exist and a small explosion occurs, the dust build-up can be dispersed into the air as a result of the relatively minor first explosion and then produce a very large secondary explosion.

When coal is freshly pulverized, volatile gases such as methane can be released and the result is no longer a coal dust/air mixture but what is termed a hybrid mixture.

Coal Mill Temperatures

Coal mill hot air inlet temperatures should never be more than 600°F and the outlet temperature should not exceed 200°F on Raymond coal mills. If the flow of raw coal to the coal mill is interrupted for any reason (for example: plugging, failure of the coal feeder, etc.), the outlet temperature of the coal mill can quickly climb to dangerous levels. The risk of explosions or fires can be extreme when the coal mill inlet temperature increases to more than 600°F or the outlet temperature is more than 200°F.

Velocity in Ducts and Burner Pipes

Fuel efficiency would tend to dictate that the airflow should be varied as the coal feed rate varies. However, velocities in ducts or conveying lines must be at least 5000 fpm (25 meters per second), which has the practical effect of limiting how much the airflow can be varied without reducing the velocity below safe levels.

Burner pipes must be designed to maintain a minimum tip velocity of 8500 fpm (45 meters per second). Velocities less than 8500 fpm substantially increase the risk of the coal flame propagating into the burner pipe and potentially through the conveying lines to the coal mill causing substantial damage to the equipment.


Raymond Mill


Combustible gases

Coal may contain trace amounts of gases such as methane. When coal is handled, it can release some of these gases. Methane concentrations in coal unloading systems, particularly in enclosed areas such as tunnels, elevator housings, and bins can accumulate to dangerous concentrations. Smoking, cutting, welding, or any source of open flame or high heat (such as a light bulb that could break and result in an electrical arc) should be strictly prohibited in coal handling areas.

Spontaneous combustion

Oxidation at the surface of a coal particle –which is most active when the coal has been freshly pulverized – and condensation of water onto the coal are reactions causing heat that can lead to spontaneous combustion.

The ease with which coal will oxidize is extremely variable. The total exposed surface area is important because, when more fresh surface is exposed, oxygen has a higher chance of uniting with the coal with the result that the total heat liberated in a given time for a given weight of coal will be substantially greater. When water condenses, it releases heat which can be a significant factor in the initial increase in temperature of a coal dust mass. However, oxidation is how the coal ultimately reaches its ignition temperature.

Spontaneous combustion is primarily oxidation occurring on a fresh surface of a coal particle. The rate of oxidation increases rapidly as the temperature increases. For some coals a temperature increase of 20°F (10°C) can double the rate of oxidation. If heating from oxidation occurs in a mass of coal dust, the ignition temperature of the coal can be reached quickly if enough oxygen is present.

When a build-up of coal dust is allowed to occur, the coal will begin to heat for reasons just explained. Therefore, it is important that all coal dust is immediately cleaned and dust is not allowed to build-up in piles.

Debris in the coal mill

Every effort must be made to prevent scrap metal and other spark producing debris to enter the coal mill system. Pieces of metal in the coal mill can also be heated to temperatures high enough to start a fire or explosion by being in the mill while it is in operation.

Solid fuel that spills over the bowl and into the area below the bowl can cause a fire since it is exposed to the hot drying air entering the coal mill. The coal mill scrapers will usually sweep the fuel pieces around to the debris chute and discharge them; however, a fire is likely to occur if a coal buildup occurs at the hot air inlet to the mill.

Hot surfaces

Hot surfaces such as hot bearings, cutting, or welding can start a coal dust fire or explosion. Any unusual temperatures must be reported immediately and steps taken to solve the problem. Cutting and welding around the coal mill system should only be done under strict supervision by qualified personnel. The system should be inerted or washed down with water prior to cutting or welding.

Coal Dust Explosions

A coal dust explosion will occur if the following three conditions exist:

  1. The concentration of coal dust in the gas mixture is within the explosion limits.
  2. The oxygen content in the gas mixture is sufficient for an explosion.
  3. There is sufficient thermal energy to initiate an explosion.

Theoretically, the absence of one of any one of these three factors would be enough to prevent a coal dust explosion. However, it is preferable to eliminate two or, possibly, all three factors.

The thermal energy required for initiating an explosion could originate from several sources:

  1. Spontaneous combustion or self-heating of the coal.
  2. Overheating of the coal by hot gases used for drying that are too hot.
  3. Overheated machine parts, such as hot bearings.
  4. Metal entering the coal mill with the coal can cause sparks or become hot enough to start a fire or explosion.


On a coal grinding and firing system, maintenance work or inspections that require opening equipment should only be performed when given specific instructions and under the direct supervision of authorized personnel. Cutting or welding around or on a coal firing system can result in fires and explosions. Opening an inspection door on a coal grinding system can provide oxygen to smoldering, powdered coal and result in fires or explosions. Use extreme caution when opening an inspection door. Do not poke or disturb any coal accumulations if there is any evidence of heat, smoke, or glowing embers. Allow the system to cool further and then check again as necessary. When you are convinced everything is OK, remove any accumulations in small amounts. Before working on or around coal firing systems, the system must be inerted or washed down with water to be sure powdered coal can not ignite.

This article was contributed by Gerald L. Young, Senior Consultant at PEC Consulting Group LLC. Jerry has authored or co-authored more than 25 papers that cover cement manufacturing and emissions control. He has conducted cement plant audits and feasibility studies for new cement plants and plant expansions. He has a BSc degree in Chemistry from Missouri University of Science and Technology, Rolla, MO, and a Master’s degree in Management from the University of Redlands, CA.

View additional feature articles under Publications.

Contact Us

Equipment tenders submitted by Original Equipment Manufacturers (OEMs) should be methodically evaluated. Tenders are first evaluated against process and technical mandatory parameters as specified in the Request for Quotation (RFQ). Bidders who do not meet design criteria are notified of discrepancies and given the opportunity to rectify them within a reasonable amount of time. A point system — which measures several pre-agreed technical, commercial, and financial parameters – is a reliable tool used to impartially measure and grade tenders. Equipment price, ease of installation, operating costs and other factors are considered in the selection process.



A point-rated evaluation system is used to determine the relative merit of each proposal. Point-rated criteria identify value-added factors and provide a means to assess and compare the offers. Key parameters like capacity, flow rates, brake power, power consumption, and fuel consumption are evaluated. Key parameters must be agreed upon by the evaluation team before the evaluation process starts. The following formulae could be used to calculate the score:

  •  When the minimum value is the most attractive value, score = avg/value x 100
  • When the maximum value is the most attractive value, score = value/avg x 100

“avg” is the average value of all the OEM offers and “value” is that which has been provided by the OEM supply being evaluated.


For example, to evaluate an ID fan for a vertical roller mill break power.




Bidder A

Bidder B

Bidder C

Fan Brake Power






First the average power value is calculated and this value is equated to 100. The average brake power value for the table above is 727 kW. In this case the lowest motor power is the most attractive feature. Then use the following formula: The score for all three bidders is listed below:





Average Value



Bidder A



Bidder B



Bidder C




In this case, Bidder B has the highest score, 110.10, because it is providing the lowest operating power demand for the fan (we are looking for the most efficient fan for the vertical mill system) This process is followed for each parameter to be evaluated. A weight is assigned to each parameter according to its importance, and each parameter score is multiplied by its weight. Weights for each feature are agreed upon before the evaluation process starts. Below is an example of a Clinker Cooler evaluation:






Weight Factor

Average Value

Bidder A


Bidder B


Bidder C


Bidder A


Bidder B


Bidder C


Area (m2)









Specific Loading









Air – Clinker ratio









Installed Power of Cooling Fan (kW)









Clinker exit temp (°C above ambient)









ID Fan Installed Power (kW)















After every parameter is analyzed and rated, all the values are added. In this case, the cooler provided by Bidder B has the highest technical score of 102.59.


2.            PROJECT COST

The equipment tender price not the sole indicator of equipment cost. There are other factors to be considered in addition to the tender price: i.e., the life cycle of the equipment, installation cost, construction of supporting facilities and operation costs.

Equipment and installation costs should be calculated for each bidder and then equalized for comparison purposes. An economic analysis must be made of the entire life cycle of the plant, not just the initial equipment purchase price. In some cases less expensive equipment may in the long term end up costing more due to higher installation and operating costs. The table below shows operating cost comparisons of power and fuel for a cement plant:


Power Consumption


Bidder A

Bidder B

Bidder C

Raw Mill (kWh/st of clinker)




Pyro-processing (kWh/st of clinker)




Coal Mill (kWh/st of clinker)




Finish Mill (kWh/st of clinker)




Misc. (kWh/st of clinker)




Total (kWh/st of clinker)




Power Cost ($/kWh)




Clinker Production (st/year)




Cost year

 $     13,050,000

 $     14,100,000

 $     15,750,000


Fuel Consumption


Bidder A

Bidder B

Bidder C

Specific heat consumption (mmBtu/st)




Power Cost ($/mmBtu)




Clinker Production




Cost year

 $ 9,468,000

 $ 9,144,000

 $ 9,036,000


Power and fuel costs are added in the table below. A score is calculated using formula avg/value x 100., where “avg” is the average total operating cost/year.  



Bidder A

Bidder B

Bidder C

Power Operating Cost

 $  14,300,000


 $  14,100,000


Fuel Operating Cost

 $   9,216,000

 $  9,468,000

 $   9,144,000

 $  9,036,000

Total Operating Cost/year

 $  23,516,000


 $  23,244,000









Point-rated criteria, project cost, and operating cost are incorporated into the overall evaluation. Weight is assigned to each parameter:



Weight Factor

Average Value

Bidder A Value

Bidder B Value

Bidder C Value

Bidder A Score

Bidder B Score

Bidder C Score

Point Rated Criteria









Total Project Cost









Total Operating Cost









Total weighted Points







Bidder B has the highest score, 101.86, followed by Bidder A.  Bidder C score, 97.15, is below average. This evaluation is not definitive, but serves as a tool for top management to make a final decision.  There are other factors that, although not quantifiable, should be considered, like client-supplier relation, services near plant location, technology, commercial terms, etc.


The main contributor to this article was Pompeyo D. Ríos, Senior Consultant & Project Manager – at PEC Consulting Group.  Mr. Ríos has a BS in Mechanical Engineering from the Universidad Metropolitana, Caracas, Venezuela, and a Master’s in Business Administration, Finance and Accounting from Regis University, Denver, CO

View additional feature articles under Publications.

Contact Us


2012-11-29 09.57.53Utilizing used equipment to build a cement plant is not always economically attractive as it may appear at face value. Although the cost of the equipment appears to be favorable, there are many factors which need to be considered in the capital cost analysis (CapEx). In most cases, the equipment is sold in place at the plant being dismantled. This is true with most major process equipment. The buyer carries the cost of dismantling, transporting, and reassembling the equipment. The buyer is also responsible for all Customs imposed export and import procedures, duties and taxes.

The analysis of the feasibility of utilizing used equipment should consider the following points:


1. The entire risk is on the Owner

Most equipment is sold on an as-is where-is basis; hence, a detailed inspection and assessment of the equipment is necessary. The seller will not provide guarantees of any kind (capacity, completeness, equipment condition warranties, etc.). The risk entirely rests with the Owner and it is high considering the ratio of equipment cost to overall investment costs, which amount to hundreds of millions of US Dollars.

2. Performance guarantees and technical support

No one, including the original OEM, will likely be prepared to provide a performance guarantee in terms of capacity, energy consumption, or quality of the equipment as is normally obtained with new equipment.

3. Schedule risks

More than likely, not all necessary plant components will be available with the existing used plant. Therefore, new parts have to be identified, ordered and then assembled. In this case, there is no advantage on the project schedule compared to using all new equipment. Production delays due to faulty equipment will result in projected cash flows not materializing because of implementation issues which may counter the savings gained from the procurement of used equipment.


cement mill building 21. Capacity of the plant

Capacities of the available used equipment will dictate the new plant capacity rather than the preferred capacity according to the determination of the feasibility study.

Unless all the used equipment comes from a single process line sized for the capacity of the new line and utilizing similar raw materials and fuels, matching the equipment to the new site may require significant modifications. Buying individual equipment is even more challenging and requires a highly skilled process engineer to match equipment to requirements. Process flow sheets and equipment lists need to be developed to prepare a “shopping list” of complementary equipment. If a complete line (raw mill through clinker cooler discharge) is identified, the process engineer needs to identify the modifications required to adjust for the conditions of the new site, such as the difference in elevation which has an effect on the amount of process gases handled.

2. System configuration

Different systems such as raw grinding, coal grinding, pyro-processing system, storage and material handling systems, may or may not be the Owner’s optimal choice for the new plant. The Owner will have to make do with what is available.

3. Electrical Systems & Controls

Highly qualified electrical and control engineers need to evaluate the equipment and determine suitability for the new site conditions. If applicable, it is likely that a power distribution system will still need to be designed and new instrumentation and control system will be required for the new plant. If the source of the equipment has different voltage and frequency ratings, it is most likely that the electrical drives will not be usable as the equipment would have been designed for different motor speeds.

4. Specific transportable equipment

While heavy equipment is economical to transport due to its high value, equipment such as cyclones, bins, process ducts is not economically transportable even if in good condition. Such equipment is made of thin plates susceptible to damage. Furthermore, the transport costs are based on volume rather than weight and therefore the costs will be disproportionately high.

5. Documentation

Documentation is one of the biggest issues with the concept of building a plant with used equipment. Documentation is very important for relocation, reassembly, and also for future maintenance. Generally, the documentation is unorganized and incomplete which becomes a challenge during reconstruction. Specifically, the structural drawings designed for equipment loads, if available, need to be reexamined. More than likely, the soil conditions and wind and earthquake loads at the new location are different and therefore the foundations and structures will have to be redesigned. The availability of equipment drawings is critical to the success of the project. If equipment drawings are not available, it will be necessary to request drawings from the OEMs to avoid the tedious work of taking dimensions in the field.

6. Dismantling of equipmentpreheater tower 2

Once used equipment is located, a team of engineers with extensive experience in equipment maintenance needs to be deployed to the site to evaluate its condition. Expertise in rotary kilns, mills, process fans, coolers and other major cement plant equipment is required to do this type of evaluation. It is rare to find used equipment that was shut down and maintained in good condition. Most companies quit doing maintenance on equipment if they know it will be shut down. If the equipment is idle for a long period of time, certain components will deteriorate. In this case, considerable effort and planning are required to ship equipment to maintenance shops to be overhauled. A skilled team of professionals should be in charge of dismantling the equipment. Match-marking and adding identification to facilitate reassembly, which is best done by the same team. The cost of dismantling depends on the country where the used equipment is located, which is most likely in western countries where costs are high. Often the equipment is still in place which will require hiring a local contractor to disassemble and ship to the new location. A company representative will need to be present to make sure this is done correctly. Steel structures cost more to disassemble and reassemble compared to new fabricated structural steel sourced in Asia.

7. Problems with identifying missing components

Ancillary Equipment: Unless a complete cement line is found that matches the desired production rate and elevation of the new site, purchasing individual equipment is “hit and miss”. Some equipment can be found, but others will have to be purchased new. Usually auxiliary equipment is not worth the effort to purchase used. This is technically the most difficult aspect of relocation projects. Several components could be missing or damaged during the shut-down period. Initial inspection or due diligence generally covers an overall visual inspection and does not include detailed inspection of each and every equipment and its internals. In many cases, parts are proprietary items that need to be procured from the OEMs. Such spares are expensive and will be disproportionate in cost to the value of the purchase price of the used equipment.

8. Transit damage

Transit damage risk will be carried by the buyer since the dismantling and packaging will be undertaken by the buyer’s contractor.


Transportable equipment is best limited to major heavy equipment. Parts made of thin plates or embedded in the concrete such as kiln base plates are either likely to be damaged or not worth transporting. Kiln shells with drive and support stations, mills, and large fans are items that may be economical to transport and reassemble.

When a cost is assigned to meet the challenges and risks mentioned above, the overall relocation project costs are generally higher than buying new equipment. However, there are always exceptions to the rule.

This article was contributed by F.M. Benavides, N. Jayaraman, and K.R. Schweigert for PEC Consulting.

View additional feature articles under Publications.

Contact Us


Simply stated, Root Cause Analysis, “RCA”, is a tool designed to help identify not only what and how an event occurred, but also why it happened. Until a determination is reached as to why an event or failure occurred, workable corrective measures that prevent future events from happening cannot be implemented. Identifying root causes is the key to preventing similar recurrences. RCA is a four-step process:

  1. Data collection. The first step in the analysis is to gather data. Without complete information and an understanding of the event, the causal factors and root causes associated with the event cannot be identified.
  2. Causal factor charting. Causal factors are those contributors (human errors and component failures) that, if eliminated, would have either prevented the occurrence or reduced its severity. Causal factor charting provides a structure to organize and analyze the information gathered during the investigation and identify gaps and deficiencies in knowledge. The causal factor chart is simply a sequence diagram with logic tests that describes the events leading up to an occurrence, plus the conditions surrounding the events.
  3. Root cause identification. After all the causal factors have been identified, root cause identification starts. This step involves the use of a decision diagram called the Root Cause Map to identify the underlying reason or reasons for each causal factor.

    The identification of root causes helps in determining the reasons the event occurred so the problems surrounding the occurrence can be addressed.

    root cause map                                                            Figure 1 – Root Cause Map1
  4. Step four—Recommendation generation and implementation. Following identification of the root causes for a particular causal factor, achievable recommendations for preventing its recurrence are generated. Understanding why an event occurred is the key to developing effective recommendations.

If the recommendations are not implemented, the effort expended in performing the analysis is wasted. Organizations need to ensure that recommendations are tracked to completion.


Imagine a case when production stopped due to equipment malfunction. The equipment was relatively new and in good condition when the failure occurred. A typical investigation would probably conclude that operator error was the cause. However, to understand the reasons for the breakdown, a more in-depth analysis should be performed. In this case, we might ask, “Was the equipment really in good shape? Was the maintenance department doing its job? Was the operator familiar with the equipment?” The answers to these and other questions will help determine why the breakdown took place and what measures should be taken to prevent a recurrence. For example, recommendations might include establishing a solid maintenance program or conducting training sessions for the operators. The results of the analysis are usually presented in a Root Cause Summary Table, which organizes the information compiled during the steps mentioned before. Each column represents a major aspect of the RCA process.

  • In the first column, a general description of the causal factor is presented along with sufficient background information for the reader to be able to understand the need to address the causal factor.
  • The second column shows the Path or Paths through the Root Cause Map associated with the causal factor.
  • The third column presents recommendations to address each of the root causes identified.

The use of this three-column format shows root causes and recommendations developed for each causal factor. Root cause summary table: Event description: equipment failure

 Casual factor #1  Paths through root cause map Recommendations
Description: Equipment has design issues
  • Equipment difficulty.
  • Equipment design problem.
  • Design input less than adequate (LTA)
  • Obtain the original design specifications from the manufacturer
 Casual factor # 2  Paths through root cause map  Recommendations
Description: Lack of organization at the Maintenance Department
  • Equipment difficulty.
  • Equipment reliability program design LTA
  • Program LTA
  • Inappropriate type of maintenance assigned
  • Establish a solid maintenance program
 Casual factor # 3  Paths through root cause map  Recommendations
Description: Employee training at the plant is lacking
  • Personnel difficulty
  • Contract employee
  • Training LTA
  • On-the-job training LTA
  • A Training Program must be established, focusing on equipment and procedures for plant efficiency and safety control.

  1 From Root Cause Analysis Handbook.  PEC Consulting is experienced in studies for the development of root cause analysis.

   This article was contributed by Lucia Martinez, Research Specialist for PEC Consulting. View additional feature articles under Publications. Contact Us    


OPEN PIT QUARRYSome limestone mines contain reserves that are massive, thick deposits with small variances in the chemistry of the limestone.  Provided there are no complicated geologic structures within the deposit, the mine can rely heavily on the original core testing data to predict the quality of the limestone feeding the plant.  Core holes can be widely spaced as long as the geology shows consistency in the reserve.  Mine sampling and testing are performed to make sure the mine stays within the boundaries of the quality horizon or seam. To maintain quality of the limestone in these types of deposits, the following methods are used:
  • Typical Method in Open Pit Quarries:

    • A quarry rotary air drill is used to find either the top (hanging wall) or bottom (foot wall) of the deposit between core holes.

    •  Samples are taken at intervals necessary to locate the quality by simply blowing out the chips at specific intervals and placing them in sample bags for testing.
    • This can be done in advance of final drilling and blasting to make sure enough overburden is removed or that the mine does not go too deep and below the foot wall.

Rotary Air Drill

  • Typical Method in Underground Mining:

In underground mining, the thickness of the quality seam will determine the number of lifts or layers that can be removed at one time:

    • For thicknesses of up to 10 meters, a single heading will remove all the limestone from the seam.
    • Thicker seams will require multiple lifts to remove all of the quality stone.
    • There may be a heading to remove the first layer followed by removal of the bench.
    • Sampling of the initial heading is usually done by taking samples of the top, middle and bottom of the mine face.  This is performed after the heading is cleaned out and scaling has removed any loose stone from the top and face.
    • Bench sampling can be done using the same method as the open pit quarry using the rotary air drill chip samples.
Picture 066There could be a certain consistent tracer seam that is visible on the core holes and assists the mine personnel in finding the head and foot wall.  A geologist should be able to point this out when he logs the core.  Mine personnel will use this as a method to stay within the seam. Plant sampling and testing of incoming limestone feed from a very consistent mine deposit can be limited to taking a sample during each shift, more for the record than to control the quality.


Sedimentary deposits that are jumbled and faulted present difficult conditions for maintaining the quality of the limestone feed to the plant.  Often these deposits contain anticlinal or synclinal folding; faulting; blocking; and, other geologic structures that make mining difficult. The more complicated the limestone structure, the more sampling and testing required to ensure the delivery of quality limestone to the process.  In these conditions, the number of core holes will have to increase to define the areas of quality limestone and the geologic structures, and to determine the “mineability” of the deposit. These types of limestone deposits are normally only mined by open pit quarrying.  Underground mining is usually too difficult to mine safely. Sampling in the pit becomes a significant part of the mining operation: MVC-006F
  • Not only are you looking for head and foot wall but also geologic structures that can cause contamination in the stone.  For instance, in an anticlinal fold, the upper portion of the reserve is in tension and the bottom is in compression.  The upper portion is prone to cracks and crevices that fill with contamination from the layers above.  In faulting, the area displaced can contain similar contamination.  If the deposit is broken up in blocks, additional testing will need to be done to determine the boundaries of the good limestone.
  • Sampling and testing in the mine will need to increase.  Chip samples along with face samples will be used to locate the areas of good quality stone.  Sometimes a geologist will need to visit the mine on a regular basis to assist the mine personnel in interpreting the location of quality stone.

Quality of the Limestone Feeding a Cement Plant:

  • These types of limestone reserves require further testing at the cement plant prior to the raw material blending process.
  • Sampling and testing must be continuous to meet certain chemical requirements.  Based upon the quality of the limestone delivered to the plant, high grade limestone, silica, alumina and iron are added to the mix to meet certain chemical properties for the formation of clinker in the kiln.
  • To ensure proper mixing, the mixture is conveyed to a specially designed homogenizing silo to further blend the raw meal prior to clinkerization.
  •  Most cement plants blend raw materials using an on-line analyzer.  The on-line analysis is imperative for the production of good quality clinker.

Quality of the Limestone Feeding a Lime Plant:

  • In the process of converting high calcium limestone into calcium oxide in a lime kiln, the rule of thumb to follow is “the more complicated the deposit, the more sampling and testing is needed prior to the kiln”.
  • There is not a whole lot that can be done with the limestone once it is fed to the kiln.
  • Unlike cement, there is usually no blending system to improve the mix.  An on-line analyzer may be employed to divert low quality limestone to waste in the crushing and screening area.

The main contributor to this article was Ken Schweigert, Senior Process Consultant at PEC Consulting Group.

View additional feature articles under PublicationsContact Us

A Plant Process Audit is a comprehensive evaluation of the overall performance of the plant’s operations. PEC Consulting systematically evaluates the plant’s operations, identifies the areas that are not working efficiently, and presents its findings and solutions to optimize the plant.

Process Audits Steps

1. Benchmarking

Modern, dry-process cement plants with efficient configuration of grinding and pyroprocessing systems typically consume less than 700 kcal/kg-cl thermal energy and 100 kWh/mt of electrical energy. Older plants have inefficient systems, which compounded with operational and maintenance inadequacies, result in much higher energy consumption. Based on the plant’s conditions and specific requirements, general benchmarking is done to set targets. Plant audits evaluate the operation of a cement plant against the appropriate benchmark. After a detailed evaluation, recommendations for plant optimization are made in three levels of capital investment: Step 1: None or very little capital investment — by making adjustments to the operational protocols and improving maintenance Step 2: Minor capital investments – with a payback within 24 months. Step 3: Major capital investments – with a 3- to 5-year payback.

2. Historic Evaluation

The plant operational and stoppage data is collected over the past two or more years. The reasons for the stoppages are analyzed in terms of category (mechanical/electrical/instrumentation/refractory/other), duration, and frequency in order to identify causes in order of severity. The plant performance is also analyzed by department. Often a department’s best performance does not occur at the same time of best performance of the plant as a whole. If we choose the best performance times of each department and make them occur at the same time, the plant performance would show a considerably higher level of efficiency. Attempts are made to make them happen at the same time, which is not an unrealistic target as the departments had indeed performed at that level in the past Through a systematic approach, all departments are made to perform at the highest possible level thus increasing the plant’s overall productivity.

3. Thermal Energy

Thermal energy relates to the Pyroprocessing system. For a 1 million mt/year clinker production, savings of 10 kcal/kg-cl would result in annual savings of approximately $185,000. (1,000,000 tpy*1,000 kg/y*10 kcal/yr * $120/t-coal (6,500kcal/kg-coal/1,000 t coal) Another significant advantage in most cases is that the reduction in heat consumption can be utilized to increase production. Potential savings can also be derived from:
  • Cooler optimization
  • Arresting in-leakages
  • Optimization of operational strategy

4. Electrical Energy

Large fans and mill drives are major consumers of electrical energy. Fans — fan power is linked to specific heat consumption and many operational parameters. Optimization of these parameters will help lowering fan power consumption. Mills – in the case of ball mills, optimization of the mill charge and upkeep of the mill internals will minimize power consumption. As for vertical roller mills, the inspection of mill internals and separator and adjustments in the operation will bring about improvements, both in energy consumption and production increase.

5. Chemistry and Operations Strategy

Clinker quality related issues are addressed by evaluating the chemistry and operational parameters.

6. Emissions Management

The inadequacy of emission management systems generally found in older plants does not meet current emission regulations. PEC Consulting can analyze emission levels and provide solutions to improve emission management. The expert staff at PEC Consulting Group has the capability to undertake Plant Process Audits and provide ongoing technical assistance to cement plants to improve operational performance. The scope of work generally includes:
  • Plant visit and discussions with the plant’s operating personnel
  • Data collection of historical stoppages and operating parameters
  • Analysis of the data to identify areas for improvement
  • Submission of a report providing observations and recommendations, including economic analysis to establish the cost/benefit ratios.
  • Develop an implementation program with the Plant Management
  • Work with Operating personnel through periodic goal-setting and audits until the prescribed performance goals are achieved.
A Plant Audit is the foundation to optimize the plant operations and often presents the lowest cost/benefit investment ratio.  
This article was contributed by Narayana (Jay) Jayaraman, Senior Consultant and Technical Services Director of PEC Consulting. He has had in-depth exposure to the technical, economic and commercial aspects of large cement projects, and has extensive experience in the upgrade and optimization of cement plants. He has a MS in Mechanical Engineering from the Indian Institute of Technology, Kharagpur, India.

View additional feature articles under PublicationsContact Us

Training imparts continuing education and brings the operators up to date in their skills to perform and respond more efficiently to emergencies. Training is essential for any organization, especially mineral processing industries, such as cement or lime plants, where continuous uninterrupted operations are key to the company’s profitability. There is significant value to a company in training its employees. Increasing the knowledge of a particular job’s function enhances the employee’s understanding of a particular process / operation. And training lifts the morale of the operating personnel and raises their consciousness on technical issues. Operating personnel are usually eager to learn advanced techniques or new skills in order to perform their duties more effectively and keep themselves updated with industry developments. Cement manufacturing is a complex process that calls for teamwork among the operators of the various units of a cement plant: Pre blending of various minerals, Drying and grinding, Homogenizing, Pre-heating and Calcining, Burning, Coal drying and grinding and Cement Grinding and Packing. The entire process also involves material handling and other mechanical operations which influence the process and eventually the operation of the plant. It is important that people fully understand how their area of work relates to the total process. Training allows them to see the “Big Picture”. During training the employees also benefit from learning recent trends in the industry and technological developments. It is an opportunity to interact with experienced personnel and experts and learn design considerations, effect of design parameters on the process and operation, etc. The specific reasons and benefits of training are shown in Figure 1 below. Figure1

What Can PEC Consulting do?

Training is imparted to make trainees understand the subject in a very simple manner. Simple language and to–the-point description make both training as well as the subject interesting. Many encouraging results such as gain in production and equipment’s operational efficiencies, increased availability and reduced downtime, and enhanced equipment safety are true benefits of training. Organizational Benefits of training are listed in Figure 2.   Figure2  

Elements of Training

Imparting training involves the following Elements as shown in Figure 3:   Figure3  

Handouts and Course Material:

Handouts and Course material are a permanent reference and guide for the participants. They broadly include:
  • Explanation on details of the subject.
  • Engineering, Design and Safety features of the equipment and Process safety.
  • Operational aspects.
  • Theoretical and Calculation elements.

Classroom Training and Group Discussion:

One-on-one and group discussions during classroom training help to better understand basic design criteria, fundamentals of various calculations, and how to make use of process parameters and information gathered to improve a given equipment’s performance. Classroom training generally covers the subjects shown below in Figure 4:   Figure4   Classroom training and group discussion also involves the following:
  • Delivering lectures and presentations.
  • Sharing Knowledge and Experience.
  • Discussion on critical aspects of plant operation.
  • Understanding the importance and inference of process parameters.
  • Analysis of process parameters.
  • Understanding Process control logics and Equipment Safety logics and their consequences.

On field or In-plant Training:

In-plant training is different from the classroom environment. On field or In-plant training provides an industrial exposure to new entrants. It enables the participants to acquire more practical knowledge of the equipment. On field or In-plant Training provides distinct advantages:
  • Equipment inspection.
  • Information on “What to look for”.
  • Physical inspection provides information on equipment conditions.
  • Practical experience of process parameters measurements.
  • Enhanced accuracy of measurements.
  • Understanding the importance of maintenance and its effects on process parameters.


A small amount of capital spent on training may be viewed as an Investment on Human Capital rather than expenditure. In simple economic terms, a 1% increase in production through less downtime and increased productivity will result in additional cement availability of 10,000 t/year from a 1 million ton/year plant. Assuming a margin of USD 40 per ton, this will yield an increased profit of USD 2,000,000 per year through a small investment in training.
The main contributor to this Article was Jagrut Upadhyay, Process Consultant at PEC Consulting Group in St. Louis.  Jagrut has a Bachelor of Science Degree in Chemical Engineering, from the D.D. Institute of Technology, Gujarat University, India

View additional feature articles under PublicationsContact Us


The first step in exploring for any mineral resource is to determine the area where the exploration will take place. The selection of the best area will increase the probability of finding a deposit. Mineral prospectivity is a predictive tool used in choosing the location for the exploration efforts. Mineral prospectivity is broadly used in the early stages of the exploration of metallic ores and industrial minerals and rocks (magnesite, fluorite, clay, graphite, etc.). It minimizes the technical and financial risks associated with decision making in mineral exploration. Depending on the quantity and quality of information available, there are two predictive modeling approaches that can be applied:

  1. A data-driven (quantitative) study if the quantity and quality of information is high.
  2. A knowledge-driven modeling (qualitative) if the information is scarce or unreliable, which focuses in the geological processes generating the desired ore type in a qualitative manner.

Geographical information systems (GIS) provide the framework to integrate the relevant exploration parameters for the targeted mineralization occurrence, such as geology, geochemistry, geophysics, land use, etc. (Fig. 1), processed by spatial data analysis techniques (weights of evidence, logistic regression, fuzzy logic, location–allocation, etc.). The results obtained from the prospectivity study are usually presented as a predictive map where, over a usually broad area (country, region, etc), the areas with a higher occurrence probability for a certain mineral are highlighted. These maps are used by the exploration team to define the areas to look in detail. Picture1

Figure 1

  For those mineral resources that are abundant, broadly distributed, and with a low unitary price (high place-value mineral commodities) like aggregates, limestone, gypsum, etc., transport costs (proportional to distance) are a key factor to be taken into account and therefore market parameters should be integrated in the GIS together with the rest of relevant information. By integrating the location of consumption points (demand), location of concurrent facilities (existing offer), and transport networks (roads, railway lines, etc.), prospectivity studies will determine the most favorable areas in term of market-capture (Fig. 2), prioritizing the areas to be investigated depending not only on the geological availability but also on market parameters. This technique can be applied for all those mineral resources where the transport costs have a high impact in the final price of the product like building materials, gypsum, frac sand, etc. Picture2

Figure 2

  A prospectivity study is an inexpensive and powerful tool that efficiently allocates the exploration resources, increasing the probability of findings, reducing the inherent risks associated to mineral resources exploration, or finding the best place, in terms of market, to locate a new mining facility.

The main contributor to this article was Dr. José Ignacio Escavy, Senior Geological Consultant at PEC Consulting Group.  Dr. Escavy has a degree in Geology from the University of Madrid, Spain; M. Sc. in Minerals Resources from the University of Cardiff, U.K.; and a Ph.D. in Industrial Minerals from the University of Madrid, Spain.

View additional feature articles under PublicationsContact Us


Understanding the market landscape is one of the most important prerequisites in strategic decision-making. More often than not, the key to competing and outperforming competitors lies in a better understanding of the key growth areas and market trends. A rigorous market study helps to support strategy development by providing valuable insights on:

  • Industry structure and trends
  • Market segments, size and growth potential
  • Demand driver dynamics and their implications
  • Competitive landscape – customers, competitors, suppliers
  • Service, product differentiation and branding
  • Market entry modes

A good market analysis comprises at least 5 important parts. image001  

Part 1: Objectives of the Research

The researcher has to provide the rationale for undertaking the study. The tasks associated are:

  • Scope of work
    • e.g., prepare for new product introduction, evaluate competitors, look for new market opportunities, etc.
  • Application of the information obtained in the Market Study
    • e.g., support a marketing plan, measure and evaluate previous marketing decision, competitive research program, etc.


Part 2: Description of the Market

  • General Description
    • A summary of the market being studied
  • Target Market(s)
    • Geographic areas selected for analysis
    • Population analyzed (e.g., demographics, psychographics, behaviors)
    • Benefits seeked (i.e., what points-of-pain or problems are being solved)
    • Factors affecting purchase or use decision
    • Attitudes about the products/services currently offered
    • Product use
  • Products and Services that appeal to the target market
    • In general terms (not particular brands) what is currently appealing to this market
    • What types of products/services may appeal to this market (i.e., what is used now to solve the problem).


Part 3: Market Metrics

Included in this section are:

  • Size estimates (current and future) for:
    • Overall market
      • Current size
      • Potential size
      • Actual penetration of current products/service within the total market
    • Individual market segments
      • Current size
      • Potential size
      • Actual penetration of current products/service within the total market
  • Growth estimates (current and future) for:
    • Overall market
    • Individual market segments
    • Relation to GDP growth


Part 4: Competitive Analysis

  • Summary of Current Competitors
    • Listing by market share ranking (by each target market if possible)
  • Current Competitors – full analysis of top competitors including:
    • Products & Services (e.g., description, uniqueness, pricing, etc.)
    • Market share
    • Current customers
    • Positioning and promotion strategies
    • Partnerships/Alliances/Distributors
    • Recent news
      • It is extremely important to focus attention on the SWOT section of this report. While most other information in this report can be gleaned from company and secondary materials, much of what appears in the SWOT section is based on the researcher’s own perceptions of the competitor based on the information collected. Consequently, this is often one of the hardest areas of the report to write.
    • SWOT Analysis – Strengths, Weaknesses, Opportunities & Threats
    • And other information (as: general company information, summary of business, business overview, recent news/developments, financial and market share analysis, marketing, and other issues like technology capability or partnership arrangements)
  • Potential Competitors
    • Explanation (though not as detailed as Current Competitors) on who they are or maybe and why they are seen as potential competitors


Part 5: Additional Information

This section of the market study includes other information including

  • Extraneous Variables
    • Discuss factors that may affect this market (e.g., technological, social, governmental, competitive, etc.)
  • Market Trends
    • What is expected to happen


This article was contributed by Lucia Martínez, Research Assistant at PEC Consulting Group.  

View additional feature articles under PublicationsContact Us


An existing plant has several old technology long rotary kilns. The client wanted to convert one of the kilns to a preheater kiln by shortening the kiln; building the preheater over the top of the kiln; new ductwork; baghouse and draft fan. There are multiple structures and equipment around the kiln, making the installation very complicated. The “as built” drawings for the plant are decades old and several modifications to the plant have been done over the years. As is normally the case, the client did not update the drawings when modifications were made. There is great potential for errors with field dimensioning in an existing plant that could lead to inaccurate design and subsequently additional installation costs. The alternative is to use 3D Scanning, which will greatly enhance the accuracy of the design and reduce construction costs, less potential for interferences and better planning of the installation. picture2

To avoid these problems, 3D Scanning was used to obtain existing structural and equipment layouts.

  • A 3D Scanner takes over 900,000 points per second with an accuracy of 2mm in 50 feet. At the same time, it photographs the surroundings to add color to the scan and provides a panoramic view from the scan location.
  • Multiple scans were taken of the area where the new equipment and structures were to be installed and stitched together creating a point cloud where all the data was stored.
  • This way, a complete replica of the plant was used for the design.
  • Interfaces were checked and interferences detected and corrected. The potential for error was greatly minimized.

The full effect of 3D Scanning was realized during the construction phase:

  • There were far less interferences in the field leading to lower construction costs.
  • The scan also picked up electrical cable tray, conduits, compressed air lines, water lines, gas lines and other items that had been added to the plant over the years.
  • Location and dimensioning of these items allowed the construction team to plan for the installation reducing site costs.


3D Scanning simplifies the measurement process and greatly increases accuracy which translates into cost savings.

The main contributor to this article was Ken Schweigert, Senior Process Consultant at PEC Consulting Group.

View additional feature articles under PublicationsContact Us