Patent ID: 7147689

Claim:
An apparatus for storing hydrocarbons with substantially zero release of volatile organic compounds (VOCs) into the atmosphere, which system is comprised of: a) a tank, wherein the tank bounds an interior area for holding a hydrocarbon material, said tank having an inlet for conducting a hydrocarbon material into said tank and an outlet for venting gases from said tank; b) a scrubber unit comprised of enclosing walls defining a lower chamber and an upper chamber, which upper chamber, is in fluid communication with said lower chamber, which upper chamber is vertically elongated with respect to said lower chamber, wherein there is also provided: i) a bed of substantially inert packing material contained in said upper chamber, wherein within said bed of packing material there provided a defoaming device comprised of a stainless steel screen which defoaming device is perpendicular to the longitudinal axis of the upper chamber, which defoaming device is cylindrical in shape and is defined by the enclosing walls of the upper chamber and an interface with the packing material at the top and bottom of said defoaming device; ii) a liquid chemical agent, comprised of a surfactant in an aqueous medium, contained in said lower chamber which chemical agent is selected from those in which the targeted VOCs are soluble, miscible, or both; iii) a first conduit fluidly connecting said lower chamber at a point below the level of chemical agent to said upper chamber at a point above said packing material; iv) a pump in-line of said first conduit for pumping chemical agent through said first conduit from said lower chamber to said upper chamber; v) an inlet port on said upper chamber at a point below said bed of packing material to allow the entry of a gaseous stream from said tank; vi) a second conduit fluidly connected to said outlet of said tank and said inlet port of said upper chamber; vii) an outlet port in said upper chamber at a point above the point at which said first conduit is connected above the packing material, and wherein there is also provided a separation device for separating liquid and particulates from the gaseous stream, which separation device is located between the outlet of said upper chamber and the point at which chemical agent is injected.