The technological difficulties and research carried out were reviewed for the cement precalciner kiln fired with high-sulfur coal as the fuel. The principle of sulfur evaporation was analyzed and solutions to reduce sulfur evaporation were sketched. Several design features which helped to eliminate build-ups were introduced. The hot issues for the application of high-sulfur coal in the cement plants were discussed, including excess air coefficient and local reducing atmosphere, the burner orientation and flame adjustment, uncombined free lime, the influence of high-sulfur coal on the sintering flux and so on. 

According to the type of DD calciner designed by my Institute for some program which its size based on experiences， the owners request us to check the design structure reasonableness now. In order to reduce the investment cost and shorten the test cycle, this paper adopts the numerical simulation technique to establish the 3D model and theory model which replaced the traditional test method. Through the simulation of internal flow field, we get the results such as the relevant pressure field, temperature field, particle flow and so on. All that will be used to prove the reasonable of the designed structure and find optimization of design scheme.

Discussed by compatibility effects of different components of grinding aids on cement and superplasticizers, it is thought that grinding aids impacted the process of cement hydration and the effective absorption of superplasticizers molecules on the cement particles.So it may lead to compatibility deterioration or improvement. Accordingly,it was proposed that selecting grinding aids of non-hazardous or less hazardous compatibility superplasticizers.

Planetary gear units is the primary part in roller press drive system. The torque balance is one of the key factors in roller press operation. In this paper, common torque support at home and abroad are summarized . Several structures,matters needing attention and economy of processing are discussed.