GB2503747A

GB2503747A - Micro liquefied natural gas plant with no loss turbo compressor

Info

Publication number: GB2503747A
Application number: GB201212157A
Authority: GB
Inventors: Kevin Peakman
Original assignee: Linde GmbH
Current assignee: Linde GmbH
Priority date: 2012-07-06
Filing date: 2012-07-06
Publication date: 2014-01-08
Also published as: GB201212157D0

Abstract

A micro LNG plant employing a refrigeration industry no loss turbo compressor in the micro LNG plant design. This design provides the advantages of micro scale LNG plants, including the production of on demand, on site LNG with minimized distribution costs, with a unit capital to product rate ratio equivalent to that achieved by small scale LNG plants and the process efficiency of large scale LNG plants.

Description

Micro LNG Plant With No Loss Turbo Compressor

FIELD OF THE INVENTION

(001) The invention relates to micro liquefied natural gas (LNG) plants that utilize refrigeration industry no loss turbo compressors for mixed refrigerant compression.

BACKGROUND OF THE INVENTION

(002) LNG is predominantly methane that has been converted from gas to liquid form for ease of storage and transportation. This is because LNG takes up about 1/600th the volume of natural gas in the gaseous state.

(003) A typical process for obtaining LNG is depicted in the drawing figure. In particular.

raw natural gas is first transported to the plant and then is processed to remove impurity gases, such as C02, H2S, and condensates such as water, oil, mud, and any trade amounts of mercury. Once purified, the natural gas is then cooled down in stages and condensed until liquefied. The resulting LNG is stored in tanks ready for shipment to market. * . .

*. . (004) Many LNG plants are very large, processing more than a million tons of LNG per year. These LNO plants are often located in relatively remote area for safety reasons and therefore the cost of transport to and from the plant is significant. Small scale LNG plants (with LNG production of 150 to 500 tons per day) have the advantageous of compact size that enables production of LNG close to the location where it will be used, thus reducing the ::::; transportation costs. In addition, small scale LNG plants have the advantage of allowing * balancing of the availability of natural gas during high and low periods of demand.

(005) Micro LNG plants (with LNG production of less than 100 tons per day and often in the range of 25 to 50 tons per day) provide advantages for smaller scale industrial needs by allowing small scale LNG production on site with the ability to meet variable demand.

However, micro LNG plants have the disadvantage that scaling down the design of a larger LNG plant results in an exponential increase in the capital equipment cost and operational costs, making the product uneconomical.

(006) There is a need in the art for improvements to micro LNG plant design and operation.

SUMMARY OF THE INVENTION

(007) The invention overcomes the problems noted above with respect to scale down of a micro LNG plant, by utilizing a refrigeration industry no loss turbo compressor in the LNG process.

BRIEF DESCRIPTION OF THE DRAWINGS

(008) The drawing figure is a general flow diagram for LNG production.

DETAILED DESCRIPTION OF THE INVENTION

(009) The invention is directed to improvements to micro LNG plants. By using a refrigeration industry no loss turbo compressor in the micro LNG plant design, it is possible to match the process efficiency of a large scale LNG plant.

(010) Micro scale LNG plants are important production tools for industry in providing on demand, on site LNG while minimizing distribution costs. However, simply scaling down * from a large LNG plant is disadvantageous as the result is an exponential increase in the unit r... capital to product rate and thus uneconomical product. This problem is overcome by the invention by using a refrigeration industry no loss turbo compressor for the refrigeration and compression operations of the micro LNG plant. By using such a compressor, the unit capital to product rate is equivalent to that achieved by small scale ILNG plants. The invention * ** provides for the economical production of LNG from a micro LNG plant.

(011) The invention provides a micro LNG plant having a capital cost, measured on the basis of dollars of capital per ton of capacity that is similar to that achieved by small scale LNG plants while also achieving process efficiencies normally associated with large scale LNG plants. The micro LNG plant of the invention is designed to provide the following attributes: Production of at least 50 metric tones of LNG per day; 25% power cost reduction as compared to micro LNG plants using nitrogen cycle refrigeration technology, e.g. reduction from about 800 kW per ton to about 600 kW per ton power consumption; Allows for modularization of plant equipment and therefore a reduction of time from equipment purchase to plant conmüssiuning; e.g. about 15 months from design to commissioning depending on local regulatory requirements.

(012) The invention provides advantages associated with micro LNG plants, such as on demand, on site production of LNG with significantly reduced transportation and distribution costs, while also exhibiting a unit capital to product rate equivalent to that achieved by small scale LNG plants.

(013) It will be understood that the embodiments described herein are merely exemplary and that one skilled in the art may make variations and modifications without departing from the spirit and scope of the present invention. All such variations and modifications are intended to be included within the scope of the invention as described above. Further, all embodiments disclosed are not necessarily in the alternative, as various embodiments of the invention may be combined to provide the desired result. * . . * S. * S * S * S..

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