초록

A process for the use of ambient air as a heat exchange medium for vaporizing cryogenic fluids wherein the vaporized cryogenic gases are heated to a selected temperature for use or delivery to a pipeline.

대표청구항 ▼

1. A method for vaporizing a liquefied natural gas stream, the method comprising: a) heating a liquefied natural gas stream in a first heat exchanger via indirect heat exchange with an ambient air stream to thereby produce a warmed, at least partially vaporized natural gas stream and a condensed wat

1. A method for vaporizing a liquefied natural gas stream, the method comprising: a) heating a liquefied natural gas stream in a first heat exchanger via indirect heat exchange with an ambient air stream to thereby produce a warmed, at least partially vaporized natural gas stream and a condensed water stream;b) cooling an exhaust gas stream from a gas turbine in a second heat exchanger via indirect heat exchange with a liquid stream to thereby produce a cooled exhaust gas stream and a first heated liquid stream;c) passing the cooled exhaust gas stream through a NOx removal unit to thereby produce a NOx-depleted cooled exhaust gas stream;d) introducing the NOx-depleted cooled exhaust gas stream into a lower inlet of a quench column;e) immediately subsequent to its withdrawal from the first heat exchanger, introducing the vaporized natural gas stream into a third heat exchanger;f) further heating the vaporized natural gas stream introduced into said third heat exchanger via indirect heat exchange with at least a portion of said first heated liquid stream withdrawn from the second heat exchanger to thereby produce a warmed natural gas product stream having a product temperature of at least 40° F. and a cooled liquid stream; andg) heating said cooled liquid stream withdrawn from said third heat exchanger in said quench column via direct heat exchange contact with said NOx-depleted cooled exhaust gas stream to produce a further cooled exhaust gas stream and a second heated liquid stream, wherein said liquid stream used to cool said exhaust gas stream withdrawn from the gas turbine in said second heat exchanger comprises said second heated liquid stream; andh) adjusting the amount of heat transferred from the first heated liquid stream introduced into said third heat exchanger, wherein said adjusting is carried out to reduce the flow rate of the ambient air stream through said first heat exchanger while still heating said vaporized natural gas stream in the third heat exchanger to the product temperature. 2. The method of claim 1, further comprising, compressing an air stream in a compressor to provide a compressed feed air stream and introducing said compressed air stream and a combustion gas stream into said gas turbine to produce energy. 3. The method of claim 1, wherein said liquid stream comprises water. 4. The method of claim 1, wherein said cooled exhaust gas stream withdrawn from said second heat exchanger has a temperature of about 55° F. to about 400° F. 5. The method of claim 1, wherein said gas turbine generates energy; further comprising using at least a portion of said energy to produce electricity. 6. A system for vaporizing a liquefied natural gas stream, said system comprising: a first heat exchanger comprising an ambient air inlet, a cooled air outlet, a liquefied natural gas inlet, and a vaporized natural gas outlet, wherein said first heat exchanger is adapted to heat and at least partially vaporize a liquefied natural gas stream via indirect heat exchange with an ambient air stream to produce a vaporized natural gas stream;a second heat exchanger comprising a cool natural gas inlet, a heated natural gas outlet, a heated liquid inlet, and a cooled liquid outlet, wherein said cool natural gas inlet is in direct fluid flow communication with said vaporized natural gas outlet of said first heat exchanger, wherein said second heat exchanger is adapted to further heat said vaporized natural gas stream via indirect heat exchange with a heated liquid stream to produce a warmed product vaporized natural gas stream and a cooled liquid stream;an air compressor comprising a feed air inlet and a compressed air outlet, said air compressor adapted to compress a stream of ambient air to produce a compressed air stream;a gas turbine comprising a compressed air inlet, an exhaust gas outlet, and a rotating shaft, wherein said compressed air inlet is in fluid flow communication with said compressed air outlet of said air compressor, wherein said gas turbine is adapted to receive said compressed air stream from said compressor, generate energy to rotate said rotatable shaft, and discharge an exhaust gas stream from said exhaust gas outlet;a third heat exchanger comprising a warm exhaust gas inlet, a cooled exhaust gas outlet, a warm liquid inlet, and a hot liquid outlet, wherein said warm exhaust gas inlet is in fluid flow communication with said exhaust gas outlet of said gas turbine, wherein said third heat exchanger adapted to cool said exhaust gas stream discharged from said gas turbine to produce a cooled exhaust gas stream;a NOx removal unit comprising a gas inlet and a NOx-reduced gas outlet, wherein said cooled exhaust gas outlet of said third heat exchanger is in fluid flow communication with said gas inlet of said NOx removal unit; anda quench column comprising an upper liquid inlet, a lower liquid outlet, a lower vapor inlet, and an upper vapor outlet, wherein said upper liquid inlet is in fluid flow communication with said cool liquid outlet of said second heat exchanger and said lower vapor inlet is in fluid flow communication with said NOx-reduced gas outlet of said NOx removal unit, wherein said quench column is adapted to heat the cooled liquid stream exiting said second heat exchanger via direct heat exchange with said cooled exhaust gas stream exiting said third heat exchanger to produce a warmed liquid stream and a further cooled exhaust gas stream,wherein said lower liquid outlet of said quench column is in fluid flow communication with said warm liquid inlet of said third heat exchanger and said third heat exchanger is further adapted to further heat the warmed liquid stream via indirect heat exchange with said exhaust gas stream from said gas turbine,wherein said hot liquid outlet of said third heat exchanger is in fluid flow communication with said heated liquid inlet of said second heat exchanger, wherein said second heat exchanger is adapted to heat said vaporized natural gas stream via indirect heat exchange with the heated liquid stream withdrawn from said third heat exchanger to thereby produce a warmed natural gas product. 7. The system of claim 6, wherein said first heat exchanger further comprises a condensed water outlet for discharging water condensed during the cooling of said ambient air stream; and further comprising a fourth heat exchanger adapted to cool an air stream prior to its introduction into said air compressor, wherein said fourth heat exchanger comprises a cool water inlet, a warm water outlet, a warm air inlet, and a cool air outlet, wherein said condensed water outlet of said first heat exchanger is in fluid communication with said cool water inlet of said fourth heat exchanger and said cool air outlet of said fourth heat exchanger is in fluid flow communication with said feed air inlet of said compressor. 8. The method of claim 2, further comprising, cooling said air stream prior to said compressing to thereby provide a cooled, compressed air stream, wherein said cooled, compressed air stream and said combustion gas stream are introduced into said gas turbine. 9. The method of claim 8, wherein said cooling of said air stream prior to said compressing is at least partially carried out via indirect heat exchange with at least a portion of said condensed water stream exiting said first heat exchanger. 10. The system of claim 6, further comprising, a generator for generating electricity, wherein said generator is configured to be rotated by said gas turbine.