In the dry process of cement production, problems such as poor unloading, arching, and blockage of wet sticky materials often occur. The process design for the feeding silo of Indonesia P14 project has been successful. This article introduces the experimental determination of the effective internal friction angle and the wall friction angle of the project, as well as the calculation of the fitting material flow function, the outlet width and the half-top angle of the overall flow cell, and the new process design method for the determination of the dimensions of the feed silo.

Conventional materials such as raw materials or cement could be grinded and sorted into product with appropriate fineness under proper operating conditions in the laboratory rolling and dry sorting system. However, some special materials need to be grinded into coarser product with dry-type sorting, high efficiency and energy saving requirment, and it is even difficult under the premise of not changing the specifications of the existing equipment. Our laboratory has been commissioned by a cooperative unit to grind a batch of lightweight samples (materials like coking coal powder) into relatively coarser product, and the requirement was still difficult to meet after many exploration tests. At last, the fineness requirement of product was satisfied after the sorting equipment was optimized and adjusted, without changing the existing equipment and the dry-type sorting condition.

An introduction was made for the development situation of spheroidal graphite iron in China, the characteristics of spheroidal graphite iron, the use of spheroidal graphite iron parts in cement main equipment as well as the comparison between the use of cast steel-made and spheroidal graphite iron-made vertical mill grinding tables in their production.

Industrial factories discharge a large amount of waste heat, which can go into boiler to produce steam, and the steam go into the steam turbine to make power for factories. Steam also can be used as the power drag large water pump, fan, compressor. It can make full use of waste heat resources, and save electric energy. Industrial drag is very normal, but double drag design is unusual. Double drag is free to switch in normal operation, to ensure the equipment run continuously.