原料粒度对铸造型焦气孔结构和表观质量的影响

Effect of size of raw material on pore structure and apparent quality of foundry formed coke

采用TG-FTIR对原料热解气的析出进行分析,通过微孔结构分析仪、扫描电镜研究半焦和焦煤粒度对铸造型焦微观结构的影响规律,并对其宏观质量进行研究.结果表明:随着温度的升高,除半焦外,其它原料都发生二次析气.随着焦煤粒度的增加,最大进汞量的峰值孔径稍有增加,峰值不断下降,且大气孔明显增多;铸造型焦的孔容、平均孔径、气孔率均增加;铸造型焦整体结构的密实性下降,大气孔数量增加,气孔壁变薄,裂纹增加;半焦的影响趋势与焦煤的一致.型焦落下强度基本都大于98%,抗压强度大于20t/个.

The pyrolysis gas of raw material was analyzed by a TG-FTIR.The effect of size of raw material on micro-pore structure of foundry formed coke was studied by micro-pore structure analyzer and SEM.The macro-quality of the foundry formed coke was investigated.The results show that with the increasing of temperature,there are double gas precipitations for the other raw materials except semi-coke.With the increasing of size of coking coal,the pore size of the maximum mercury rate has a little increase,while the peak value of the maximum mercury rate decreases and the number of large pores increases obviously.The porosity,pore cubage and the average pore size of the foundry formed coke increase.The density of foundry formed coke and thickness of pore wall of coke decrease,while the number of large pore and crack increase.The influencing tendency of semi-coke granularity is consistent with that of coking coal.The shatter strength and tensile strength of foundry formed coke are bigger than 98% and 20 ton per one,respectively.