Cement Manufacturers Association (CMA)

52 Factors to Consider during Design Phase Every cement plant is a unique case, when it comes to its requirement for grinding aids and/ or chemical additives. The designing of the chemical additive must be undertaken as a “solution” rather than a “product”. The following factors should be considered while designing Grinding Aids and Performance Enhancers. 1. Characteristics of Input Materials such as Clinker, Gypsum, Fly Ash, Slag etc • a. Mineralogy • b. Physical properties • c. Chemical properties 2. Nature of plant and equipment • a. Cement mill type • b. Cement mill setup • c. Process parameters 3. Market dynamics • Minimum compressive strengths desired by the end-users of cement in the catchment market • Other quality parameters such as setting times, blaines and residues required by the market • Price points of cement for specific grades and qualities. 4. Cost dynamics • Cost of input materials such as clinker, y ash, slag etc: An analysis of input material costs would help understand the most appropriate cement composition from the cost perspective and subsequently designing the performance enhancer to derive the greatest impact. For instance, in certain instances it may be more prudent to replace clinker with one kind of SCM rather than the other, leading to a slightly dierent design of performance enhancer formulation. • Cost of power: This would help understand the trade-off between grinding finer v/s designing a performance enhancer for appropriate chemical activation at a coarser particle size distribution. For instance, when the cost of power is prohibitively high, it would be increase the commercial viability of deploying a premium performance enhancer that would deliver desired quality norms even with coarser grinding of cement. • Cost of available gypsums: Trade-off between cost and impact on quality due to usage of one gypsum v/s another should be considered while designing the required performance enhancer. For instance, phospho gypsum provides a less expensive proposition to many cement producers, albeit at the risk of retardation in setting times and strength development in the resultant cement.