氯盐及其复配阻化剂对煤氧化抑制作用的实验研究

Experimental study on inhibition effect of chlorine and its compound inhibitors on coal oxidation

氯盐是矿井煤自燃阻化防控技术中较为普遍使用的阻化剂。为提升煤自燃的阻化效果和氯盐阻化剂的性能,选取阜生煤矿煤样,采用程序升温的方法,分别研究了水及浓度均为20%的NaCl溶液、KCl溶液、CaCl_(2)溶液对煤氧化的影响规律,并优选出CaCl_(2)与茶多酚进行复配,对比分析不同复配比例阻化剂对煤氧化的抑制作用。结果表明:水和氯盐溶液使相同温度下煤氧化气体中的O_(2)体积分数升高、CO和CO_(2)体积分数降低,表观活化能增大,对煤氧化产生抑制作用,其中CaCl_(2)溶液的阻化效果最好,平均阻化率约为66.00%,相对于水的平均阻化率提升了24.61%,且阻化效果较为稳定;CaCl_(2)/茶多酚复配阻化剂进一步提升了阻化效果,阻化率随着茶多酚质量分数的增大而增大,其中茶多酚质量分数为6%、CaCl_(2)质量分数为14%时,阻化效果较好,平均阻化率达到了75.37%,且阻化效果比单一CaCl_(2)溶液的阻化效果更为稳定,继续增大茶多酚的质量分数,则阻化效果的提升不明显。因此,一定质量分数的CaCl_(2)与茶多酚复配可以提升阻化率,同时降低CaCl_(2)的用量。

Chlorides are the commonly used inhibitors in inhibition technology for coal spontaneous combustion prevention and control in coal mine.To improve the inhibition efficiency on coal spontaneous combustion and the inhibition performance of chlorides,the coal samples from Fusheng coal mine were selected.The influence of water and NaCl,KCl,CaCl_(2)solutions with 20%concentration on coal oxidation were investigated based on temperature-programmed method.Moreover,CaCl_(2)was found to be with the best inhibition efficiency,which was then compounded with tea polyphenols(TP).The influence of CaCl_(2)/TP inhibitors with different compound ratio on coal oxidation were further analyzed.The results indicate that both water and chloride solutions increase the volume fraction of O_(2)and decrease the volume fraction of CO and the volume fraction of CO_(2)in the product gases of coal oxidation;meanwhile,the apparent activation energy increases.All these indicate the inhibition effect on coal oxidation.Among the chlorides,CaCl_(2)presents the best performance.The average inhibition efficiency reaches approximately 66.00%,which increases by 24.61%compared to that of water.CaCl_(2)/TP inhibitors further improve the performance compared to single CaCl_(2)solution,and the inhibition efficiency increases with the increase of mass fraction of TP.Among the CaCl_(2)/TP inhibitors,the compound with 6%mass fraction of TP and 14%mass fraction of CaCl_(2)presents better efficiency,whose average inhibition efficiency reaches 75.37%,and are more stable than CaCl_(2)solution.The improvement of efficiency is not obvious when further increasing the mass fraction of TP.Therefore,a certain percentage for the compound of CaCl_(2)and TP not only improve the resistance performance,but also reduce the use level of CaCl_(2).