Study On Removal Process Of Low Concentration CO₂ By High-gravity Technology

With the development of high-technology exploration facilities,closed/semi-closed equipments such as deep submersibles,manned spaceships,and air-raid shelters have achieved wide applications.The removal of carbon dioxide(CO2)is one of the key issues related to air quality in confined spaces.Additionally,fire is one of the main problems that endanger the human life in confined spaces and CO2 concentration will insignificantly increase after extinguishing fire,and whether the air quality can be restored in a short period is directly associated with the safety of human life.Furthermore,the size and space room of closed space determine the complexity and CO2 removal performance of equipment,and no additional harmful gases and substances are allowed.Therefore,the closed-space CO2 removal technology is unique,effective and complex.High-gravity technology is a new-type process intensification technology and it can efficiently reduce the size of equipment and space room,which is widely applied in the field of gas purification.In this paper,the high-gravity technology is used for CO2 removal with low concentration of 0.5-2%and lowering the size of equipment,which provides the fundamental data for developing low-concentration CO2 removal technology.In this paper,K2CO3/KOH and MDEA/PZ mixed solutions were used as the absorbents for CO2 absorption in a rotating packed bed(RPB)to explore the effects of operation conditions on CO2 removal efficiency and obtain the fundamental data,which provides the fundamental data and support for the size-up of reactor and industrial application.The main conclusions are as follows:(1)When K2CO3/KOH mixed solution is used as absorbent,the results show that,both of CO2 removal efficiency and KGa first increased and then became flatted with an increases in rotation speed,liquid flow rate and temperature,and decreased with an increase in carbonization degree;the optimal operation conditions were:rotation speed of 1200 rpm,liquid flow rate of 12 L/h,and temperature of 40 ?;the applicability of using K2CO3/KOH mixed solution as absorbent was verified by this paper and a suitable change in operation conditions or adding new absorbent can efficiently lower the outlet CO2 concentration;(2)When MDEA/PZ mixed solution is used as absorbent,the results show that,both of CO2 removal efficiency and KGa first increased and then became flatted with an increases in rotation speed,liquid flow rate and temperature,and decreased with an increase in carbonization degree;the optimal operation conditions were:rotation speed of 1200 rpm,liquid flow rate of 12 L/h,and temperature of 40?;the applicability of using MDEA/PZ mixed solution as absorbent was verified by this paper,which provides a reference for the industrial application.