Experimental Study On Thermoelectric Distillation System With Synergistic Multiplication Of Heating And Cooling

Distillation is the most mature and widely used separation process in chemical and related industries.Distillation,however,is an energy-intensive process.Evaporation requires a lot of energy to vaporize the liquid,while condensation requires low temperatures to liquify the gas.Therefore,how to solve the problem of high energy consumption of distillation liquid in traditional distillation unit has become the subject of many scholars.The application of thermoelectric module in distillation unit can effectively solve the problem of high energy consumption in traditional distillation unit.In this paper,a thermoelectric distillation device with natural convection at the hot end of the thermoelectric module was designed and built.Anhydrous ethanol was used as the target liquid for experimental study.The heating and cooling capacity of thermoelectric module and its influence on the energy efficiency ratio of distillation system were studied by changing the number of cooling plates,the flow rate of circulating water and the voltage of cooling plates.The main conclusions are as follows:(1)Increasing the number of refrigerated tablets from 2 to 6 can increase the ethanol yield by 176.2% and the energy efficiency ratio by 66.6%.(2)Ethanol yield increased by 83.7% when the cooling chip voltage increased from 11 V to 15 V,and the energy efficiency ratio was the highest at 13 V(229.9%).(3)Under given operating conditions,the circulating water flow rate had no significant effect on ethanol yield.Secondly,a thermoelectric distillation device was designed and built with forced convection at the hot end of the thermoelectric module.The distillation experiment was carried out with ethanol solution with a concentration of about 51.4%.The heating and cooling capacity of thermoelectric module and its influence on the energy efficiency ratio of distillation system were studied by changing the number of cooling plates,the circulation velocity of heating liquid and the voltage of cooling plates.The main conclusions are as follows:(1)Increasing the number of refrigerated tablets from 4 to 8 can increase the ethanol yield from 57.53 g to 124.45 g,and when the number of tablets is 6,the energy efficiency ratio is the highest(i.e.128%).(2)When the refrigeration chip voltage increases from 11 V to 15 V,the system energy efficiency ratio decreases;when the voltage is 11 V,the system energy efficiency ratio is the highest,which is 130%;and when the voltage is 13 V,the ethanol yield is the highest,which is 124.45 g.(3)The higher the circulation velocity of the heated solution,the higher the ethanol yield within 10 minutes.At the same time,the energy efficiency ratio of the system also increases with the increase of the circulation velocity of the heated solution.