Method for the production of liquefied natural gas

Abstract

A method for the production of liquefied natural gas (LNG) without the use of externally provided electricity is provided The method may include the steps of: providing a transportable apparatus, wherein the transportable apparatus comprises a housing, a heat exchanger, a phase separator, a first refrigeration supply, and a second refrigeration supply, wherein the first refrigeration supply and the second refrigeration supply are configured to provide refrigeration within the heat exchanger; introducing a natural gas stream into the transportable apparatus at a first pressure under conditions effective for producing an LNG stream; withdrawing the LNG stream from the transportable apparatus; and withdrawing a warm natural gas stream from the transportable apparatus, wherein the warm natural gas stream is at a second pressure, wherein the second pressure is lower than the first pressure.

Description

RELATED APPLICATIONS[0001]This application claims priority to U.S. Provisional Application Ser. No. 62 / 201,947, filed on Aug. 6, 2015, U.S. Provisional Patent Application No. 62 / 305,381, filed on Mar. 8, 2016, and U.S. Provisional Application Ser. No. 62 / 370,953 filed on Aug. 4, 2016, all of which are hereby incorporated by reference in their entireties.TECHNICAL FIELD OF THE INVENTION[0002]The present invention generally relates to a method and apparatus for producing liquefied natural gas (LNG) in a packaged unit without any rotating machinery.BACKGROUND OF THE INVENTION[0003]There are numerous reasons for the liquefaction of gases, including naturally occurring gases such as methane. Perhaps the chief reason is that liquefaction greatly reduces the volume of a gas, making it feasible to store and transport the liquefied gas in containers of improved economy and design. Liquid gases can be stored in suitably designed cryogenic containers and dispensed into vehicle tanks using tech...

AI Technical Summary

Benefits of technology

This patent describes a way to make liquefied natural gas (LNG) using a mobile apparatus. The invention offers a less costly, more efficient, and flexible way to produce LNG without the need for expensive electricity or rotating machines. The invention utilizes a natural gas letdown system to create a packaged unit that can produce LNG in a safe and reliable way.

Problems solved by technology

However, producing liquid from methane may not be achieved with high pressure alone.

Unfortunately, the cost and maintenance of such plants is expensive because of the cost of constructing, operating and maintaining one or more external, single or mixed refrigerant, closed-loop cooling circuits.

Such circuits typically require the use and storage of multiple highly explosive refrigerants that can present safety concerns.

Refrigerants such as propane, ethylene and propylene are explosive, while propane and propylene, in particular, are heavier than air, further complicating dispersion of these gases in the event of a leak or other equipment failure.

The equipment used to liquefy cryogenic gases in high volumes is large, complex and very expensive.

Materials required in conventional liquefaction plants also contribute greatly to the plants' cost.

Another distinguishing feature of a conventional liquefaction plant in the prior art is that as a result of its complexity and size, the plant, by necessity, is typically a fixed installation that cannot be easily relocated.

Even if a conventional plant can be physically relocated, such a move is very costly and requires the plant to be out of service for many months while plant systems, components and structures are disassembled, moved and then reassembled on a newly prepared site.

While the Engel process produces LNG without the use of external refrigerants, the process yields a small volume of LNG compared to the amount of work required for its production, thus limiting the economic viability of the process.

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