基于配煤技术改善无烟煤煤灰熔融性及气化反应性

Improving ash fusibility and gasification reactivity of anthracite based on coal blending technology

为改善无烟煤的煤灰熔融性及气化反应性,选取某晋城无烟煤(JC)和印尼褐煤(YN)为原料,利用灰熔融测定仪、TGA、XRD、BET等分析测试方法,考察了YN煤的配入对JC煤煤灰熔融温度、煤焦气化活性、煤焦微晶结构、煤焦比表面积和孔容的影响。结果表明,添加YN可有效降低JC煤的灰熔融温度,当添加量达40%时,流动温度TF降至1 387℃,且煤焦反应性得到明显改善;当YN添加量达40%时,碳转化率达到50%的时间t0.5仅需27.2 min,约为JC煤焦的一半,且反应性指数R_(0.5)与碱性因数Bf之间存在较好线性关系。同时拟合煤焦的XRD数据发现,随YN的配入层间距d_(002)、芳香层片堆垛高度L_(c)、芳香度f_(a)、芳香层数N均减小,添加YN使煤焦微晶结构更加趋于无序化,且添加比例越大,石墨化抑制程度也越大。煤焦的比表面积和孔体积与YN的添加量相关,当添加40%时,比表面积可达81.102 m^(2)/g约为JC的42倍,且孔体积比JC高出一个数量级。

To improve the ash melting and gasification reactivity of anthracite coal,a Jincheng anthracite coal(JC)and Indonesian lignite coal(YN)were selected as raw materials,and the effects of YN coal addition on the ash melting temperature,gasification activity,microcrystalline structure,specific surface area and total pore volume of coal char were investigated by using ash melting tester,TGA,XRD,BET and other analytical test methods.The results show that the ash melting temperature of JC coal could be effectively reduced by adding YN,and the flow temperature T F decreases to 1387℃when the addition amount reaches 40%,and the coal char reactivity is also obviously improved,and the time required to reach 50%carbon conversion t 0.5 is only 27.2 min when YN is added at 40%,which is about half of that of JC coal char,and there is a good linear relationship between the reactivity index R_(0.5) and the alkalinity factor B f.The XRD data of coal char are also fitted and found that the layer spacing d_(002),aromatic lamellae stacking height L_(c),aromaticity f_(a),and number of aromatic layers N decreases with the addition of YN,and the addition of YN makes the microcrystalline structure of coal char more disordered,and the greater the addition ratio,the greater the degree of graphitization inhibition.The specific surface and total pore volume of coal coke are correlated with the addition of YN,and when 40%is added,the specific surface area could reach 81.102 m^(2)/g about 42 times that of JC,and the total pore volume is one order of magnitude higher than that of JC.