侧反应器与精馏塔集成(SRC)是塔内耦合反应精馏(RD)的新拓展,同时适用于反应与精馏处于相同工况和不同工况两种情形。以甲苯氯化连串反应为研究对象,分别建立了RD和SRC过程的数学模型,在相同总塔板数和塔釜上升蒸气量条件下,计算了相同工况下(反应与精馏压力均为101.3kPa),RD与SRC过程的气/液流率、温度、组成分布,发现两者性能具有一致性。在此基础上,以产品氯化苄的生产成本为目标函数、标志系统产能的氯气进料流率和分配比例为优化变量,对甲苯氯化连串反应的相同工况RD与SRC过程、不同工况SRC过程(反应压力为101.3kPa、精馏压力为10kPa)进行优化,结果表明,相同压力工况下,优化得到的RD与SRC的装置产能与产品质量一致;但在不同压力工况下,SRC的产能明显提升、产品质量也有所提高,反映出不同工况SRC明显的优势。
Compared to a conventional reactive distillation(RD)process combining reaction and separation in a single unit,the distillation column coupled with side reactors(SRC)as an advanced integrated reaction and separation technology can be applicable to the reaction system whether the conditions for reaction and separation are harmonious or mismatched.For the typical consecutive reaction system of benzyl chloride production,the mathematic models of RD and SRC were firstly established.On this basis,under the same total column stages and bottom vapor boil-up rate,process simulation was performed for the given RD and SRC processes,in which the pressures for reaction and separation were set to 101.3 kPa.The results showed that there were consistent vapor and liquid flow rates,temperature, and composition profiles in the given RD and SRC flowsheets.Furthermore,for the given RD and SRC processes operated under the same pressure of 101.3 kPa,and the SRC process,in which the pressures for reaction and separation were respectively fixed at 101.3 and 10 kPa,feed flow rate of chlorine and distribution ratio of chlorine as two critical variables deciding production capacity were optimized by minimizing total costs.Optimization results showed that consistent system performance was achieved in the RD and SRC processes operated under 101.3 kPa,while obviously increased production capacity and improved product purity were observed in the SRC process with reaction and separation operated under different pressures.