Process Simulation And Optimization Of Solvent And Butadiene Recovery Unit Of Butadiene Rubber Production Process

Butadiene rubber is an important chemical product and its production process consists of aggregation,coagulation,post-processing,solvent recovery and purification and so on.In the production process of nickel butadiene rubber,the steam consumption of solvent and butadiene recovery step takes up about 40% of the entire production process,therefore,the energy conservation of the solvent and butadiene recovery step is very important.In this thesis,the solvent and butadiene recovery step of a petrochemical company is taken as the research objects.The process simulation software Aspen HYSYS is used for modeling,simulation and optimization.The company originally utilized raffinate as the polymerization solvent.However,since its composition is more complex and the energy consumption is high,thus the raffinate was then replaced by hexane solvent.This thesis performed the modeling and simulation for three processes,which include the original process with raffinate solvent,the process with the replaced hexane solvent and the new process with replaced hexane solvent and direct withdrawal.The simulation results were compared with practical industrail operating data to validate the reliablity of the simulation.In addition,the energy consumption of different processes were analyzed and compared and the results show that the total energy consumption of all the reboilers is reduced by 14.11%.The feed of recovery step can be divided into light,middle and heavy three parts on the basis of relative volatility.This thesis introduces the DWC(Dividing-Wall Column)into the process.Firstly,this thesis investigated the models for shortcut and rigorous simulation of DWC.Next,the novel process for solvent and butadiene recovery embeded with the DWC is proposed.The key design parameters are optimized and the comparision is performed with the previous three processes.The results show that,the total energy consumption for all the reboilers is reduced via 33.69% compard with the original process,and 22.80% compared with the process replaced hexane solvent and direct withdrawal.The work showed a new way for the energy saving of solvent and butadiene recovery unit.