煤化工石脑油作为乙烯裂解原料的技术分析

Technical analysis of coal chemical naphtha as pyrolysis raw material of ethylene

关键词:  煤化工石脑油  乙烯裂解原料  裂解温度  产物收率  液相芳烃含量

Key words:  coal chemical naphtha  pyrolysis raw material  pyrolysis temperature  product yield  content of liquid aromatics

摘要:

由物性分析可知,煤化工石脑油中易裂解的链烷烃含量高(>90%(w)),环烷烃、芳烃含量较低,芳烃潜含量低；结合860~900 ℃下裂解气/液相产物收率对比可知,煤化工石脑油为优质裂解原料,适宜在高温(900 ℃)下进行裂解；随着裂解温度升高,裂解液相收率降低,液相中芳烃含量提高,裂解液相以C₅～205 ℃组分为主(>75%(w)),苯、甲苯、二甲苯合计占70%(w)以上。与炼厂拔头油、石脑油相比,煤化工石脑油价格低、产量将逐年增加,裂解乙烯、三烯收率高而液相产物收率略低,因此,煤化工石脑油作为乙烯企业原料结构的合理补充,将是解决乙烯原料短缺和提升煤炭资源深加工经济效益的新路径。

Abstract:

The physical properties analysis results show that the content of paraffin in the coal chemical naphtha is high (>90 wt%), the content of naphthenes and aromatics is less, while the content of latent aromatic is low. By comparing the pyrolysis gas/liquid product yield of coal chemical naphtha at 860-900 ℃, it shows that the coal chemical naphtha is a high quality pyrolysis raw material, which is suitable for pyrolysis at high temperature (900 ℃). With the increase of pyrolysis temperature, the pyrolysis liquid phase product yield decreases and the content of aromatics in the pyrolysis liquid phase product increases. The pyrolysis liquid phase product is based on C₅-205 ℃ component as the main component (>75 wt%), of which benzene, toluene, xylene together account for more than 70 wt%. Compared with the refinery head oil and naphtha, the price of coal chemical naphtha is low, the output will increase year by year, the yield of pyrolysis ethylene and triene is high and the yield of pyrolysis liquid phase product is slightly lower. Therefore it will be a new path to solve the shortage of ethylene raw materials and enhance the benefits of deep processing of coal resources by taking the coal chemical naphtha to be a reasonable supplement of ethylene enterprise raw material resources.