影响特级苯纯度的原因分析及应对措施

Analysis of the Causes Affecting the Purity of the Premium Grade Benzene and the Relevant Control Measures

通过定性定量实验,确定了影响特级苯纯度的主要杂质:环己烷、甲基环己烷、甲苯,并对杂质的性质、来源及分离方法进行研究;分析了工艺上影响特级苯纯度的几个关键操作过程,有针对性地制定了控制粗苯原料质量、提高溶剂质量、稳定加氢系统操作、调整脱重操作指标、调节萃取操作、降低纯苯塔塔底温度等措施;使纯苯纯度由原来的99.90%提高到99.95%以上,质量等级由优等品提高到特等品。

The qualitative and quantitative tests on the purity of the pure benzene showed that the main impurities affecting the purity of the premium grade benzene were as follows： cyclohexane, methylcyclobexane and toluene. The na- ture of the impurities, their source, and separation method were studied. Some key operation processes affecting the purity of the special grade benzene were analyzed. A lot of measures were worked out to control the quality of the raw materials for crude benzene production, improve the solvent quality, stabilize the operation of the hydrogenation system, adjust the heavy ends removal and extraction operation, decrease the bottom temperature of the pure benzene column, etc. Through such measures the benzene purity was improved from 99.90% to 99.95% and above, and the product quality was raised from the excellent grade to the premium grade.