Simulation Of VOC Adsorption Removal Process Based On Aspen Adsorption

With the development of China's national economy,organic solvents are more and more widely used in industrial production and daily life.The production of a large number of VOC emissions will not only cause serious environmental pollution and harm to human health,but also cause a waste of resources.In this paper,a complete VOC variable temperature adsorption process was established based on the functions of various modules of Aspen plus software,and the influence of operating conditions on the adsorption process was studied.With Aspen simulation software,VOC emissions were treated by adsorption and azeotropic distillation.Through the change of operating pressure,operating temperature,adsorbent dosage,feed gas velocity and other operating conditions to get the influence of different operating conditions on the adsorption curve and adsorption tower axial distribution of different time and through the simulation to determine the operating cycle of VOC temperatureswing adsorption removal process,compared the factors such as volume,adsorbent adsorption pressure adsorption removal process of the change of VOC is warm.Results show that(1)adsorption removal of VOC is warm adsorption cycle associated with adsorbent adsorption amount of ethyl acetate,(2)the operating pressure increased,the saturated adsorption quantity increases,penetrating point moves to the right,to extend the adsorption cycle.(3)an increase in the amount of adsorbent can be extended through time,and the adsorbent dosage,the greater the effect on the mass transfer coefficient,the greater the results in the decrease of mass transfer rate,the extension of adsorption time.(4)starting from 0 s,ethyl acetate begins to adsorb at the bottom of the adsorption tower and forms an adsorption mass transfer zone.As time goes on,the adsorption mass transfer zone moves along the axis of the adsorption tower toward the bottom of the tower.(5)as the adsorption process is exothermic,the adsorption rate increases with the increase of temperature,the penetration point of the adsorption curve moves to the left,and the adsorption capacity of the adsorption column decreases.Using Aspen plus simulation azeotropic distillation section,using sensitivity analysis tool plate number,reflux ratio and feed position,the influence of feed temperature on the product,the results showed that:(1)with the increase of number plate,gradually increased the concentration of ethyl acetate and reduce the reboiler heat load at the same time,considering the cost problem,the finished plate number is 8.(2)The closer the feeding position is tothe tower kettle,the less favorable it is to improve the product purity.(3)increasing reflux ratio can effectively improve product purity and reduce equipment costs: however,if the reflux ratio is too high,the operation cost of the distillation tower will increase and the cold and heat load will increase,so the reflux ratio is determined to be 0.5 after comprehensive consideration.(4)increasing the feed temperature can reduce the heat load of the reboiler,but also reduce the concentration of ethyl acetate.The concentration of 99% ethyl acetate can be obtained through the optimized process,which meets the industrial recovery requirements.