Improving the effective utilization rate of clinker in cement grinding

In order to improve product quality and ensure product competitiveness in the market, cement enterprises improve product quality and reduce process manufacturing costs by adjusting batching scheme, improving calcination and grinding technology. In addition, improving the clinker effective utilization rate and particle shape is also one of the most effective schemes to improve the early strength and strength enhancement rate of cement. 
1 Effect of gradation and morphology of cement particles on strength 
Determination of residual components in 1.1 cement 45 m sieve 
According to the test requirement, the 45-micron sieve residue of different kinds and grades of cement in Shandong Cement Company was determined. The results of determination of cement proportion, 45-micron sieve residue composition and control index of sieve residue were statistically analyzed. The results are shown in Table 1. 
1.2 effect of cement particle size matching on cement performance and strength 
1) < 1 m particles do not contribute to strength because they are completely hydrated during mixing with water. The increase of the content indicates that the grinding energy is wasted and the water requirement is increased and the pouring performance is reduced. Therefore, particles of this component should be reduced as far as possible. 
2) 1~3 particle size of M is high, 3D strength is high, water demand will increase correspondingly, and pouring performance will decrease. Therefore, the particles should be as low as possible when the 3D strength meets the requirements. 
3) The higher the particle content of 3-16 micron, the more thoroughly the clinker plays, and the higher the admixture content under the same conditions. 
4) it is generally believed that 3~32 m particles play a major role in 28d strength. It is a waste of clinker and should be reduced as far as possible to lower the hydration rate of < 32 micron particles, especially < 64 micron particles. 
5) In recent years, cement products have not been satisfied with the simple pursuit of cement paste strength, but also put forward higher requirements for durability, in which the compact cement accumulation will undoubtedly reduce water demand, reduce the porosity of products, improve their strength and durability, and the compact cement accumulation is closely related to cement particle size distribution.  
6) If the admixture can complement the clinker in grain size and form the best accumulation, the addition of admixture will not only reduce the cement strength, but also increase the strength. 
At present, the best cement particle size distribution is generally recognized in China as follows: 3-32 micron particles > 65%; 3-16 micron particles as much as possible; < 3 micron particles 10%; less than 64 micron particles as better. Table 2 is the contribution of different particle sizes to cement strength.