The Research On The Optimization Of Ventilation Of Ammonia Microleak In The Liquid Ammonia Refrigeration Room

Most refrigeration systems use ammonia refrigeration systems.However,when the ammonia is stored and used,it is prone to poisoning and explosion accidents.After investigation,nearly 1/5 of ammonia refrigeration enterprises of Lanling have different levels of ammonia micro leakage,this threats the workers’ health,accumulation of ammonia may explode,there is big security risk.Good ventilation can alleviate the impact of the leakage and prevent ammonia spreading to the whole room,effective ventilation can reduce leakage of ammonia concentration,both to protect the occupational health of the workers,can also avoid the leakage of ammonia gas accumulation,prevent exploding.In this paper,the numerical simulation of natural ventilation and mechanical ventilation is carried out by using CFD numerical simulation technique for typical liquid ammonia refrigeration room.The ammonia concentration in several sections of the plant is analyzed under different exhaust modes.Under the investigation of a number of rooms,a typical case is used to improve the exhaust program.This paper puts forward three improved design schemes from the aspects of the choice of exhaust mode and the amount of air blower and exhaust fan mode.The first improvement program is to open the door and all the windows of the room,using air convection to accelerate the spread of ammonia,reduce the ammonia concentration,the plant produced a different cross-section of ammonia concentration cloud.The second improvement program is to keep the refrigerator room door and all the windows opend,setting a exhaust fan of 50 cm * 50 cm * 40 cm,power is 0.4kw,volume is 15000m3 / h in the top of the right side of the room,the plant produced a different cross-section of the concentration of ammonia cloud map.The third option is to maintain the second improvement program,the exhaust fan is changed into 90 cm * 90 cm * 40 cm,0.7kw,30000m3 / h,The plant produced a different cross-section of the concentration of ammonia cloud map.The results of the analysis provide a theoretical basis for the selection of the exhaust system and the choice of the exhaust fan,which has certain theoretical and practical significance for reducing the ammonia concentration in the refrigeration room and improving the safety of the ammonia-related refrigeration enterprises.