Investigation Of Oil Vapor Recovery Technology In Product Oil Depot Based On Closed Vapor Collection Of Tanks

Atmospheric pollution and oil resources waste due to oil evaporation loss occur in the process of product oil storage and transportation.Nowadays.the oil and gas recovery system in product oil depot is mainly aimed at collecting hydrocarbon gas generated by vehicle and vessel loading.Therefore,it is necessary to operate closed recovery on hydrocarbon gas in the storage process.There are few studies on the closed vapor collection system and the safety of the product oil tanks.In order to provide reference for design and further research on closed vapor collect system,the necessity of closed vapor collection is illustrated based on calculating the engineering example of evaporation loss data during “large and small breathing” process.Ultimate principles,technological processes and technical features in all kinds of hydrocarbon recovery methods are stated,combined hydrocarbon recovery schemes and scale-determining method of vapor recovery devices are proposed,and selection steps of recovery schemes are concluded,as well as the closed vapor collection system of the product oil tanks,the empirical computing formula of hydrocarbon gas emission amount in vehicle and vessel loading system.Based on engineering practice and design research,this paper also presents the positive and negative pressure liquid sealing processes corresponding to non-toxic and toxic light oil products.The composition of closed vapor collection system are stated,and operating principals,structures and key design parameters of the positive and negative pressure liquid sealing tank are proposed.Variation tendency of gas gathering lines in positive and negative pressure tank is analyzed and the method for determining the distance between liquid level and vapor outlet of the bottom chamber in positive and negative pressure tank is studied by utilizing energy conservation law and Stocks law.To give the reference design data for closed vapor collection system,the paper also illustrates the classification protection structures for the product oil tanks,and conducts value explanation for determining the protection parameters.The oil vapor recovery mode based on closed vapor collection system is analyzed,and the “independent subsystem of vapor recovery mode” is proposed as a basic engineering application suggestion.Based on the oil depot closed vapor collection and loading system,a specific engineering project is used for analysis.It analyzes the closed vapor collection system,the process design and plane design layout of loading facility,and it synthetically expounds the application of the vapor collection system of product oil depot in the engineering design.