Shenzhen is a first-tier city in China and has the reputation of an international garden city. Therefore, the environmental protection department of Shenzhen is also very strict in its environmental management. In particular, the fume emission from the catering industry affects the city appearance and environment, and also affects people's physical and mental health. It is expressly stipulated by Shenzhen Environmental Protection Bureau that all catering industries must install a ball-protecting fume purifier to pass the environmental protection examination and approval, and other conditions must be met, and the smoke exhaust pipe must go to the roof to realize high-altitude discharge. There must be a partition between the dining kitchen and the residents. In principle, the first floor smoke discharge is not approved. It is also necessary to provide information that meets the examination and approval in accordance with environmental protection regulations. Therefore, the owners who need to open the catering industry must implement the examination and approval in advance, otherwise they will do business at a loss. Discharge concentration of oil fume purifier and minimum removal efficiency of oil fume purification equipment. On the basis of absorbing the advantages of similar products at home and abroad, it is mainly used for the purification and treatment of low-altitude kitchen fumes; Used in hotels, restaurants, restaurants, restaurants, schools, institutions, factories and other places; Food frying, cooking and processing industries; Oil spill heat treatment workshop, oil mist lubrication workshop, workpiece welding workshop and olefin boiler discharge and other industrial occasions. The national standard of cooking fume purification treatment in catering industry is "Cooking fume emission standard" GB18483-2111. All the sales of such products must obtain the national environmental protection product certification (CCEP certification) to prove that they meet the national standards before they can be sold. It can only be sold if it is beneficial to health and the environment. Alkaline liquor is used as a detergent, and the oil fume is purified by contact with the oil fume by spraying, and then collected and discharged by an exhaust fan. At present, the oil fume removal rate of the best products is about 31 ~ 41%. The oil fume removal rate does not meet the requirements of GB18483-2111.