热解气氛对煤催化热解焦油品质的影响

为考察不同热解气氛对煤热解产物分布及焦油品质的影响，在固定床反应器内，以粒径范围为0.2～0.5 mm的和什托洛盖煤为研究对象，依次考察了热解温度、热解气氛和模拟热解气（SPG，N2+H2+CH4+CO+CO2）经过不同填装催化剂后对煤热解产物分布及焦油组成的影响。实验结果表明：N2气氛下，煤在550～750 ℃范围内进行热解时，在600 ℃热解时的焦油产率最大，为15.0%，是格金理论焦油产率的83.3%；在考察各热解气组分及模拟热解气对煤热解特性的影响时，发现以模拟热解气为热解气氛时，焦油中轻质焦油质量分数（沸程＜360 ℃）为63.2%，比在N2气氛下提高6.6%；当煤在通过各种催化剂层后的模拟热解气氛中热解时，获得的焦油产率均下降，但焦油中轻质焦油质量分数显著提高。其中，当模拟热解气通过Ni，Mo质量比为1∶1的4%Ni-4%Mo/HZSM-5催化剂时，煤热解焦油中轻质焦油质量分数为68.6%，这比无催化剂条件下煤在模拟热解气氛以及N2气氛中获得的轻质焦油质量分数分别提高8.5%和15.6%。

Effect of pyrolysis gas on the tar quality from coal catalytic pyrolysis

In order to study the effect of pyrolysis gas on the product distribution and the tar quality from coal catalytic pyrolysis，the pyrolysis of Heshentuoluogai coal，having a particle size range of 0.2-0.5 mm was conducted in a fixed bed reactor at varied pyrolysis conditions.The effect of pyrolysis temperature on the performance of coal pyrolysis was investigated in a N2 atmosphere.The highest tar yield of 15.03%，which is about 83.3% of the theoretical value confirmed by Gray-King assay，was obtained as the coal was pyrolyzed at 600 ℃ in the investigated temperature range of 550-750 ℃.When coal was pyrolyzed at 600 ℃ in simulating pyrolysis gas (SPG)，the fraction of light tar in it reached 63.2%，about 6.6% higher than that in N2 atmosphere.Any kind of catalysts that separately placed above coal layer showed a negative effect on tar yield but leaded to an improvement in the fraction of light tar.Especially for 4%Ni-4%Mo/HZSM-5 catalyst，light tar fraction reached to 68.6%，15.6% and 8.5% higher than the values obtained from coal pyrolysis in the N2 and SPG atmosphere at the absence of catalyst.