Simulation And Optimization Of Reactive Dividing Wall Column For C₃ Alkyne Selective Hydrogenation Process

In order to reduce effectively the refrigeration cost for the conventional liquid hydrogenation process of selective hydrogenation of C3 alkyne into alkene in a ethylene process,novel configurations are proposed for the process involving pre-demethanizer,demethanizer,deethanizer and C3 reactor.The proposed configurations are simulated,optimized and analyzed through process simulation.In this study,to evaluate each process,the original prefrationator sequence distillation process is resored and optimized,then catalytic distillation technology is applied to enhance the original process;as a result,conversion rate of C3 hydrogenation is raised and the operating cost is reduced by combining separation and reaction.Moreover,the effect of operating pressure on the behaviours of the catalytic distillation process with deethanizer and the possibility of applying thermal coupling are investigated by simulation.Then dividing wall column(DWC)configurations are proposed for the catalytic distillation process,and effective energy saving and reduction in total annual cost(TAC)are realized by the thermal coupling effect of the DWCs.Effect of heat transfer across the patition wall on economical efficiency in catalytic distillation deviding wall column processes is investigated by process simulation,and the effectiveness of energy saving in thermally coupled configuration is validated.The research results show that,catalytic distillation technology can save total annual cost by 0.819% in comparation with the orginal process,and the number changed into 0.759% after deenthanizer pressure is increased.Whereas,the total annual cost saving of three deviding wall colomn processes are up to 4.107%,6.420% and 10.337% respectively,among which the fully thermally coupled configuration with an intermediate condensing perfoms the best.Catalytic distillation can raised conversion rate of hydrogenation,while the energy saving is dominated by the deviding wall colomn configuration itself.The heat transfer across the dividing wall has limited effect on the economic behaviours,and the total annual cost saving are shifted to 2.339%,6.420%,9.514%,respectively for the three DWC configurations.The consideration of the heat transfer across the dividing wall increases the reliability of the simulation results in this paper for practical applications.