US 6,635,119 B1 · Method of cleaning pressurized containers containing liquified petroleum gas

Abstract

The present invention relates to a method of cleaning a container having an amount of liquefied petroleum gas contained therein. The container is first inspected thoroughly for leaks. Heated nitrogen gas is then fed into the container. The heated nitrogen gas may be transported from a nitrogen storage tank to the container via at least one pipe. Liquid nitrogen may be fed into a vaporizer for vaporizing the liquid nitrogen. The nitrogen gas may then be heated via a steamer to expand the nitrogen gas and ensure that no liquid nitrogen enters the container. The heated nitrogen gas may vaporize any liquid liquefied petroleum gas contained therein. Further, the heated nitrogen gas may transport the liquefied petroleum gas to a flare for incineration. The heated nitrogen gas may be added any number of times to reduce the concentration of the liquefied petroleum gas therein to a desired level. The container may then be steam cleaned and opened to enter and thoroughly clean or inspect the inside of the container.

Claims20

Dependent claims

A method of cleaning a pressurized container, the method comprising the steps of:

providing a pressurized container containing an amount of liquefied petroleum gas wherein the container has inlet and outlet valves;
injecting a first quantity of heated nitrogen gas into the container to vaporize said liquefied petroleum gas and form a first nitrogen gas/petroleum gas mixture;
venting the first nitrogen gas/petroleum gas mixture to a flare to incinerate the petroleum gas and release the nitrogen gas;
injecting a second quantity of heated nitrogen gas into the container to vaporize remaining liquefied petroleum gas and form a second nitrogen gas/petroleum gas mixture;
venting said second nitrogen gas/petroleum gas mixture to, the flare to incinerate the petroleum gas and release the nitrogen gas;
and
repeating the injection into the container of heated nitrogen gas and venting the mixture to the flare until the concentration of petroleum gas within the mixture reaches a predefined limit.

4 more elements

A method of cleaning a pressurized container, the method comprising the steps of:

providing a pressurized container having an amount of liquefied petroleum gas therein wherein the container has a plurality of valves;
injecting a first quantity of heated nitrogen gas into the container to vaporize the liquefied petroleum gas and form a first nitrogen gas/petroleum gas mixture;
venting the first nitrogen/petroleum gas mixture to a flare to incinerate the petroleum gas and release the nitrogen gas;
injecting a second quantity of heated nitrogen gas into the container to vaporize remaining liquefied petroleum gas and form a second nitrogen gas/petroleum gas mixture;
venting said second nitrogen gas/petroleum gas mixture to the flare to incinerate the petroleum gas and release the nitrogen gas;
and
repeating injecting the container with the heated nitrogen gas and venting the mixture to the flare until the concentration of the vaporized petroleum gas within the mixture reaches about 0%.

4 more elements

Dependencies are inferred from the claim text.

Method of cleaning pressurized containers containing liquified petroleum gas

Life of this patent

Method of cleaning pressurized containers containing liquified petroleum gas

Life of this patent

Abstract

Claims20