The paper has further discussed the steel-made outer-screw chute successfully used in ground surface coal bin at Chengzhuang Colliery thus maintaining higher percentage of lump coal and analysis is made on mode [(of the outer- screw chute and the motion of coal flow)(.

Technique study for increasing lump coal rate;

To attain the satisfied lump coal rate,the key is reasonable picks-lacing.

Research on reducing boulder yield of medium-length hole blasting;

Technology measures of lowing blasting boulder yield in Shuiyueyan surface limestone mine;

To lower blasted boulder yield is one of the most important technical considerations in deep-hole blasting operations of mine.

Method for rapid determination of caking rate of com pound fertilizer;

Based on the different proportions between stearamine and paraffin wax as raw materials,as well as combined with urease inhibitor and nitrification inhibitor,a new anti-caking agent is developed,and compared the 2 factors water absorption and caking rate with previous anti-caking agents existing in the current markets.

Based on the research on colooision blasting of small compensation space,the cause of boulder t the first stage of the first stage of Dahongshan Copper Mine is found out,so as to take measures for improve the blast technique,cut down the boulder frequency and improve the quality of blasting.

The problem about boulder frequency because of the frozen coal seam has been overcome.

After explosive properties and charging explosive structure are changed,for decreasing the big blasting block of medium-deep hole blasting the Houzhuang mine destrict of Jinling iron mine has taken some steps,for example to increase properly density factor value of blasting hole,etc The big block ratio is decreased from 25% to below 10