Apparatus and method of controlling gasoline vapor emissions

Abstract

An apparatus and method of controlling and abating gasoline vapor emissions which occur at a gasoline service station during transfer of liquid gasoline from a gasoline supply tank truck to underground storage tanks at the station and also during transfer of liquid gasoline from the underground storage tanks to the gasoline tank of an automobile through a service station gasoline pump. Vent outlet pipes of the underground storage tanks are manifolded to a common vent pipe where vapor pressure is sensed by a plurality of preset pressure sensing means to direct vapors from the vent pipe to a burner means under predetermined below atmospheric pressure or vacuum conditions. A compressed air source provides pressure air for directing the gasoline vapors to the burner means as by suction pumping and to also actuate valve means in the gas vapor line to permit flow of vapors to the burner means. A pilot system for the burner means is also provided which includes the use of gasoline vapors from the vent line and an air actuated valve for causing the vapors to move to the pilot burner. The burner means is a multistage burner in which one or both of the burners are operable depending upon the pressure vacuum condition in the vent line as sensed by the plurality of pressure sensing devices. An apparatus and method in which safety features are provided; for example, failure or absense of pressure air will prevent flow of vapors to an air booster means and to the burner means.