多级梯度冷凝回收合成革尾气中DMF的工艺模拟与优化OA

Exhaust gases emitted during synthetic leather production contain significant concentrations of volatile organic compounds(VOCs),notably N,N-dimethylformiamide(DMF).Direct emission may lead to environmental pollution and resource loss.In this work,a multistage gradient condensation recovery model was developed in Aspen Plus for a DMF,toluene,methyl acetate,and butanone multiphase waste-gas system.Two typical operating conditions with condensation temperatures of 0 ℃ and-35 ℃ were respectively analyzed.Concurrently,the air dehumidification process,the multistage gradient condensation configuration and the condensation temperature were optimized.For a synthetic leather exhaust gas flowrate of 14859kg/h,the optimal operating conditions are a condensation temperature of-35 ℃,eight trays in the absorber,a tri ethylene glycol(TEG)circulation rate of 16000kg/h,and a stripping-gas flow rate of 1500kg/h.In this case,the DMF recovery reached 99％,energy consumption increased to 54kW·h,and exergy efficiency improved to 38％.Additionally,the highest net economic benefit(396CNY/h)was obtained at a third-stage condensation temperature of-25℃.Overall,these results indicate that multistage gradient condensation enables efficient DMF recovery from synthetic leather exhaust gases.At the same time,it provides notable economic benefits while maintaining environmental performance,offering a viable technical route for green,low-carbon,and sustainable development in the synthetic-leather industry.