Apparatus and method for cleaning underground liquid fuel storage tanks

摘要

An apparatus and method are disclosed for cleaning and removing particulates from underground liquid fuel storage tanks which typically have restricted access openings to the interior thereof. The apparatus is provided with a main fuel pump having an inlet and outlet, an inflow passage communicating with the pump inlet for conducting fuel to the pump from an underground liquid storage tank, and an outflow passage communicating with the pump outlet for returning fuel from the pump to the same underground tank. The inflow passage is provided with protective strainer and a jet pump for increasing and maintaining the rate and velocity of fuel flowing therethrough to the main pump. The method of the present invention involves the steps of first dislodging, suspending, and removing particulates from the tank by withdrawing the fuel and suspended particulates from the tank through an outer passage of a coaxial hose, filtering the particulates from the fuel, and discharging filtered fuel back into the tank through an inner passage of the coaxial hose at a high velocity to dislodge and suspend particulates in the tank into the fuel.