苯-乙醇-水三元共沸物的模拟分离

SIMULATED SEPARATION OFBENZENE-ETHANOL-WATER TERNARY AZEOTROPE

基于Aspen Plus流程模拟软件,提出了精馏-液液萃取相结合的分离工艺,以得到质量分数分别为99.9%苯和95.0%的乙醇,及净化水中苯和乙醇的质量分数均低于5×10^-4为目标,确定了预分离塔、乙醇回收塔、萃取塔的最佳工艺参数。预分离塔的理论板数为11,进料位置为第10块理论板,塔顶采出量为176.0 kg/h;乙醇回收塔的理论板数为20,进料位置为第14块理论板,塔顶采出量为105.15 kg/h;萃取塔的理论级数为8。

Basing on the process simulation software of Aspen plus,the combined separation process of distillation and liquid-liquid extraction was put forth to reach the targets such as 99.9 wt%benzene and 95.0 wt%ethanol were obtained,the mass content of both benzene and ethanol in the treated water was below 5×10-4.The optimum process parameters of pre-separation tower,ethanol recovery tower and extraction tower were determined.The optimal parameters were as follow,theoretical plate number of the pre-separation tower was 11 and the feedstock position was the 10th theoretical plate,recovery of the pre-separation tower top was 176.0 kg/h,theoretical plate number of the ethanol recovery tower was 20 and the feedstock position was the 14 th theoretical plate,recovery of the tower top was 105.15 kg/h,theoretical stage of the extraction towers was 8.