The characteristic of bed formation of roller mill is discussed by applying powder engineering． The proper structure of roller table is analyzed by the author． The related matters, such as power calculation is also presented here．

Based on the data of test and production, and in reference of statistic information and documents, a comparative analysis is made on utilizing of phosphorus gypsum and polished ceramic flotsam for Portland cement production by applying life－cycle assessment in this paper． The affect of cement production, such as raw materials preparation, power and coal production, on the environmental load of per unit cement was investigated here． The results show that the impact of cement production on environmental load mainly reflected on the consumption of non－generation energy and non－reclaiming source, as well as green house effect． The author proposed that, comparing the traditional method, the environmental loads can be reduced by utilizing phosphorus gypsum and polished ceramic flotsam．

Through building general model, parameters are optimized on multi-stage flashing waste heat power generation. It has the feature of simple utilization and convenient for computer application for using matrix model. The change of flashing degree, which impact on system function and exergy recovery rate is analyzed here. The result can provide theoretical guide and reference basis for optimal design of low temperature waste heat generation．