分壁式精馏塔精制丁二烯流程模拟

丁二烯是一种重要的石油化工烯烃原料,由于其生产过程能耗高,因此节能降耗成为丁二烯生产工艺的研究热点。利用Aspen Plus模拟软件对丁二烯精制工艺的两套流程进行了模拟研究,考察了分壁式精馏塔(DWC)中内部互连物流连接位置、预分离塔气液相流量和回流比对分离效果和热负荷的影响,对比了相同分离条件下DWC分离流程和传统顺序分离流程的能耗,并根据两套分离流程中塔内液相丁二烯浓度分布情况,分析DWC的节能原因。结果表明,当主塔理论板数105,预分离塔理论板数56,进入预分离塔气相流量1020kmol/h,液相流量890kmol/h,回流比7800时,DWC分离效果最好,丁二烯质量分数可达99.7%,这为DWC精制丁二烯工艺的工业化提供了理论依据。由于DWC有效减少了精馏过程中的返混效应,提高了能量利用率,使其冷凝器可节能29.36%,再沸器可节能29.19%,存在明显的节能优势。

Simulation of butadiene distillation process using dividing wall column

Butadiene is an important petrochemical olefin raw material. Due to the high energy consumption, energy saving has become the focus in the butadiene production process research. This research simulated the two butadiene distillation processes using Aspen Plus software, and investigated the influences of intraconnection stage, vapor and liquid flow of side column and reflex ratio on the separation effect and reboiler duty in dividing wall column(DWC). This research also compared the energy consumption of the DWC process and the conventional process under the same separation conditions and analyzed the reason why DWC can save energy according to the butadiene concentration distribution in the liquid of columns. The results showed that the separation effect of DWC was the best and the butadiene concentration was up to 99.7% when the number of theoretical plates in main column was 105, the number of theoretical plates in side column was 56, vapor flow was 1020 kmol/h, liquid flow was 890 kmol/h and reflux ratio was 7800. This study provided the theoretical basis for the industrialization of DWC butadiene distillation process. As DWC can avoid the backmixing effectively and enhance the energy efficiency, the condenser and reboiler of DWC process can save energy up to 29.36% and 29.19% respectively.