State of the Art in Blended Cements 

In the manufacturing of Blended Cements, expensive clinker is substituted with other cementitious materials such as granulated slag, fly ash, or other naturally occurring pozzolanic materials resulting in different types of Blended Cements with unique properties.

The advantages of Blended Cements over Ordinary Portland Cement (OPC) are:

  1. Higher cement output for the same clinker production.
  2. Lower production costs since the substitute materials are cheaper than clinker.
  3. Superior properties for certain applications because of the strength, lower hydration heat, and high performance of Blended Cements.
  4. Environmentally-friendly due to fuel savings and the reduction of CO2 emission on the basis of per kg product.


Careful attention to the following guidelines should be given when making reliable Blended Cements:

  1. Evaluation of the availability and economics of the additive to be used
  2. The specific application of the Blended Cement
  3. Percentage addition of the substitute materials d. Water demand
  4. Fineness of the product - needs to be ground finer than OPC
  5. Grinding system capacity and system configuration
  6. Drying requirement since generally the substitute materials contain higher moisture
  7. Inter-grinding or Inter-blending and separate storage for the product
  8. Strength development curve
  9. Heat development during hardening
  10. Market acceptance of the proposed product


In addition to the use of hydraulically active components such as granulated slag, pozzolana or fly ash, certain inert materials such as limestone could be added. While this addition does not contribute to the cement strength, it acts as a filler and may contribute to the workability of the cement paste. It is necessary to evaluate the quality of the limestone to make sure that the overall quality of the cement is not affected.

PEC Consulting Group has assisted cement companies with the evaluation of their raw materials and their existing systems and provided them with basic and conceptual engineering for the production of Blended Cements. We can coordinate with reputed testing facilities to evaluate different materials to be blended and recommend optimum parameters.

Sample Scopes of Work include:

  • Feasibility and Technical Studies for Greenfield grinding plants
  • Feasibility and Technical Studies for developing the optimum system for manufacture of Blended Cements
  • Investigation of potential Blend Materials in coordination with laboratories and evaluating the properties of Blended Cements
  • Feasibility studies for converting OPC grinding systems to manufacture Blended Cements
  • Equipment Selection. Flow sheets, layouts, equipment lists and basic designs. Basic equipment specifications. Technology comparisons of major process equipment tenders
  • Capital cost and operating cost estimates of the project
  • Logistics
  • Economic viability analysis of the project


A Feasibility Study is the foundation for good project development and it is an absolute necessity for successful investments. By delivering a well prepared and thorough study, PEC Consulting helps its clients achieve their desired goals and maintain a competitive edge.

Main feature contributor: Narayana "Jay" Jayaraman

View additional feature articles under Publications. Contact Us