Liquefied natural gas-freon electricity generation system

Claim 1

A method of generating power utilizing a refrigerant as the working fluid and for limiting the temperature of the refrigerant below its decomposition range of temperature, the method including the steps of circulating the refrigerant in a closed circuit through a storage tank, a compressor, a heating means, a gas turbine, and a condensing means, characterized in that the refrigerant, after passing through a high-pressure gas turbine (5), is reheated and is then passed through a low-pressure gas turbine (7).

Claim 2

A method of generating power utilizing a refrigerant as the working fluid and for limiting the temperature of the refrigerant below its decomposition range of temperature, the method including the steps of circulating the refrigerant in a closed circuit through a storage tank, a compressor, a heating means, a gas turbine, and a condensing means, characterized in that the refrigerant, after passing through a high-pressure gas turbine (5), is reheated and is then passed through a low-pressure gas turbine (7).

Claim 9

The method according to claims 1 or 2, characterized in that the means for heating the refrigerant comprises a heat exchanger (3) where there refrigerant is vaporized by flowing in heat-exchange relationship with steam from a cooling water system of an industrial plant.

Claim 12

An apparatus for generating power, comprising a refrigerant and refrigerant storage means; a refrigerant compressor coupled to said storage means for pressurizing said refrigerant; refrigerant heating means for heating said refrigerant leaving said compressor; a high pressure gas turbine driven by vaporized refrigerant from said heating means and producing output mechanical energy, the temperature of the refrigerant being limited below its decomposition range of temperature by said high pressure gas turbine; reheating means for heating said refrigerant leaving said high pressure gas turbine; a low pressure gas turbine driven by vaporized refrigerant from said reheating means and producing output mechanical energy; a first heat exchanger functioning as a refrigerant condenser for refrigerant leaving said low pressure gas turbine; a pump for receiving refrigerant condensate from said first heat exchanger, routing it back to said refrigerant storage means; and a condensate heating means interposed between said pump and said storage means for heating and thereby vaporizing said refrigerant condensate.

Claim 13

An apparatus for generating power, comprising a refrigerant and refrigerant storage means; a refrigerant compressor coupled to said storage means for pressurizing said refrigerant; refrigerant heating means for heating said refrigerant leaving said compressor; a high pressure gas turbine driven by vaporized refrigerant from said heating means and producing output mechanical energy, the temperature of the refrigerant being limited below its decomposition range of temperature by said high pressure gas turbine; reheating means for heating said refrigerant leaving said high pressure gas turbine; a low pressure gas turbine driven by vaporized refrigerant from said reheating means and producing output mechanical energy; a first heat exchanger functioning as a refrigerant condenser for refrigerant leaving said low pressure gas turbine; a pump for receiving refrigerant condensate from said first heat exchanger, routing it back to said refrigerant storage means; and a condensate heating means interposed between said pump and said storage means for heating and thereby vaporizing said refrigerant condensate.

Claim 18

The apparatus as claimed in any one of claims 11, 12 to 15, comprising a regeneration means including means for extracting a part of the freon from a mid-stage of said high pressure turbine and mixing the extracted part with cold freon from said storage tank and routing the mixture through said heating means and back to the input of said high pressure turbine.

Claim 19

The apparatus as claimed in any one of claims 11, 12 to 15, wherein the working refrigerant has a freezing point below -82° C. and wherein said means for condensing the refrigerant is a gasification plant for gasifying liquid natural gas and is constructed such that the refrigerant flows in heat-exchange relationship with the liquid natural gas.

Claim 21

The apparatus as claimed in any one of claims 11, 12 to 15, wherein said apparatus is a duplex apparatus and includes a second closed circuit containing a second refrigerant colder than the refrigerant working in the first apparatus, said second closed circuit comprising: a second pump for pumping second refrigerant condensate through said first heat exchanger in heat exchange relationship with said first refrigerant, said first heat exchanger heating and thereby vaporizing said second refrigerant; a third gas turbine driven by vaporized second refrigerant from said first heat exchanger and producing output mechanical energy; and a second heat exchanger functioning as a second refrigerant condenser for second refrigerant leaving said third gas turbine, said second heat exchanger receiving liquefied natural gas as an input, heating said liquefied natural gas in heat exchange with said second refrigerant, and outputting natural gas.