Crude oil storage tanks are used to regulate the flow of oil between production wells and the trucks or pipelines that will transport it to the refinery. Although crude oil usually is only stored for a short period, natural gas dissolved in the crude oil can vaporize and collect at the top of the tank. Vapor recovery units have be fitted onto storage tanks to collect these so-called “fugitive emissions” for use as fuel and reduce the chances that gas vapors will be released into the environment.
The units work like vacuum cleaners, removing vapors at the top of the tank, but do so without reducing pressure in the top of the tank. Vapors are then pressurized for sale or use on site as a fuel.