Method for production and supply of a densified liquid oxygen product for space vehicle applications

Abstract

A system and method for the production and supply of a densified, liquid oxidant to a space vehicle launch facility with one or more launch platforms is provided. In one embodiment, a low pressure gaseous oxygen stream is piped from a nearby air separation unit to the space vehicle launch facility where it is then liquefied and densified in a two-stage, integrated liquefaction/densification system. In an alternate embodiment, a liquid oxygen stream produced at an air separation unit is densified in a two-stage, integrated densification system at or near the air separation unit with the resulting densified liquid oxygen product transported via truck/trailer to a nearby space vehicle launch facility.

What is claimed is: 
     
         1 . A method of supplying a densified, liquid oxygen stream for a space vehicle launch, the method comprising the steps of:
 (i) producing a gaseous oxygen stream in an air separation unit;   (ii) directing the gaseous oxygen stream via a pipeline from the air separation unit to a space launch facility, the space launch facility having one or more launch platforms;   (iii) liquefying and subcooling the gaseous oxygen stream in a first refrigeration stage to yield a subcooled, liquid oxygen stream;   (iv) densifying the subcooled, liquid oxygen stream in a first refrigeration stage to yield a densified, liquid oxygen stream;   (v) directing the densified, liquid oxygen stream to one or more storage tanks disposed at the launch facility;   (vi) suppling the densified, liquid oxygen from the one or more storage tanks to a space vehicle at least one of the one or more launch platforms;
 wherein the first refrigeration stage is disposed at the launch facility and is configured to receive a first refrigerant and flow the first refrigerant through a first primary heat exchanger to cool the gaseous oxygen stream and then through a first subcooler to subcool and liquefy the cooled gaseous oxygen stream via indirect heat exchange with a residual portion the first refrigerant to yield the subcooled, liquid oxygen stream; and 
 wherein the second refrigeration stage is disposed at the launch facility proximate the first refrigeration stage and is configured to flow a second refrigerant through a second heat exchanger to subcool the liquid oxygen stream and yield a densified, liquid oxygen stream. 
   
     
     
         2 . The method of  claim 1 , wherein the first refrigerant comprises nitrogen and the second refrigerant comprises a nitrogen and neon containing mixture. 
     
     
         3 . The method of  claim 1 , wherein the first refrigeration stage is a reverse Brayton cycle refrigeration stage and wherein step (iii) of the method further comprises the steps of:
 (a) splitting the first refrigerant flowing through the first primary heat exchanger is split into a first warm portion of the first refrigerant stream in a first warm refrigeration circuit, a second cold portion of the first refrigerant stream in a second cold refrigeration circuit, and a residual portion of the first refrigerant stream in a residual refrigeration circuit;   (b) expanding the first warm portion the first refrigerant stream a warm turbine to yield an intermediate pressure warm exhaust;   (c) expanding the second cold portion the first refrigerant stream a cold turbine to yield an intermediate pressure cold exhaust;   (d) expanding the residual portion of the first refrigerant stream;   (e) recycling the warm exhaust and the cold exhaust in one or more recycle circuits to cool the gaseous oxygen stream;   (f) subcooling and liquefying the cooled gaseous oxygen stream via indirect heat exchange with all or a part of the expanded residual portion of the first refrigerant stream to yield the subcooled, liquid oxygen stream and a first refrigerant return stream;   (g) recycling the first refrigerant return stream via the one or more recycle circuits; and   (h) further compressing the recycled warm exhaust, the recycled cold exhaust, and the recycled first refrigerant return stream in one or more first refrigerant recycle compressors.   
     
     
         4 . The method of  claim 1 , wherein step (iv) of the method further comprises the steps of:
 (a) compressing the second refrigerant in a second refrigerant recycle compressor to yield a compressed second refrigerant;   (b) cooling the compressed second refrigerant in an auxiliary heat exchanger via indirect heat exchange with a diverted portion of the cold exhaust;   (c) expanding the cooled, compressed second refrigerant in a second refrigerant turbine;   (d) densifying the subcooled, liquid oxygen stream via indirect heat exchange against the expanded second refrigerant to yield a densified, liquid oxygen stream; and   (e) recycling the warmed diverted portion of the cold exhaust to the one or more first refrigerant recycle compressors.   
     
     
         5 . The method of  claim 3 , wherein:
 the expanded residual portion of the first refrigerant stream is split into a first expanded residual portion and a second expanded residual portion;   the first expanded residual portion is received by the first subcooler and the second expanded residual portion is further expanded and recycled via the first heat exchanger as a low pressure return stream; and   the low pressure return stream is compressed in the one or more first refrigerant recycle compressors.   
     
     
         6 . The method of  claim 5 , wherein the first refrigeration stage further comprises a nitrogen subcooler configured to subcool the low pressure return stream via indirect heat exchange with the expanded residual portion of the first refrigerant stream. 
     
     
         7 . A method of supplying a densified, liquid oxygen stream for a space vehicle launch, the method comprising the steps of:
 (i) producing a liquid oxygen stream and a nitrogen refrigerant from an air separation unit;   (ii) cooling the nitrogen refrigerant in a first refrigeration stage comprising a first heat exchanger;   (iii) cooling a helium or neon containing second refrigerant in a second heat exchanger in a second refrigeration stage via indirect heat exchange with one or more streams of the cooled nitrogen refrigerant;   (iv) subcooling and densifying the liquid oxygen stream in a densification heat exchanger in the second refrigeration stage via indirect heat exchange with the cooled second refrigerant to yield a densified, liquid oxygen stream; and   (v) transporting the densified, liquid oxygen stream to a launch facility via truck.   
     
     
         8 . The method of  claim 7 , wherein the first refrigeration stage is a reverse Brayton cycle refrigeration stage and wherein step (ii) of the method further comprises the steps of:
 (a) splitting the nitrogen refrigerant flowing through the first heat exchanger into a first warm portion of the nitrogen refrigerant stream, a second cold portion of the nitrogen refrigerant stream, and a residual portion of the nitrogen refrigerant stream;   (b) expanding the first warm portion the nitrogen refrigerant stream in a warm turbine to yield an intermediate pressure warm exhaust;   (c) expanding the second cold portion the nitrogen refrigerant stream in a cold turbine to yield an intermediate pressure cold exhaust;   (d) expanding the residual portion of the nitrogen refrigerant stream to yield an expanded residual stream;   (e) recycling the warm exhaust, the cold exhaust, and at least a portion of the expanded residual stream in one or more recycle circuits to cool the nitrogen refrigerant stream; and   (f) compressing the recycled warm exhaust, the recycled cold exhaust, and the recycled expanded residual stream in one or more nitrogen refrigerant recycle compressors.   
     
     
         9 . The method of  claim 8 , wherein the second refrigeration stage is a closed loop refrigeration stage and further comprises a second refrigerant recycle compressor disposed downstream of the second heat exchanger and configured to compress the second refrigerant; and a second refrigerant turbine disposed upstream of the second heat exchanger and configured to expand the compressed second refrigerant. 
     
     
         10 . The method of  claim 8 , further comprising the steps of:
 splitting the expanded residual stream into a first expanded residual stream and a second expanded residual stream;   further expanding the first expanded residual stream to yield a low pressure return stream;   recycling the low pressure return stream via the first heat exchanger to cool the nitrogen refrigerant stream;   wherein the second expanded residual stream is one of the one or more streams of the nitrogen refrigerant flowing through the second heat exchanger to cool the helium or neon containing second refrigerant.   
     
     
         11 . The method of  claim 10 , wherein the warmed, low pressure return stream is compressed in the one or more of the nitrogen refrigerant recycle compressors. 
     
     
         12 . The method of  claim 10 , wherein the warmed, second expanded residual stream is recycled to the one or more of the nitrogen refrigerant recycle compressors. 
     
     
         13 . The method of  claim 8 , further comprising the step of diverting a portion of the cold exhaust to through the second heat exchanger as one of the one or more streams of the nitrogen refrigerant flowing through the second heat exchanger. 
     
     
         14 . The method of  claim 13 , further comprising the step of recycling the warmed, diverted portion of the cold exhaust to the one or more of the nitrogen refrigerant recycle compressors.
 the cooled gaseous oxygen stream via indirect heat exchange with a residual portion the first refrigerant to yield the subcooled, liquid oxygen stream; and   wherein the second refrigeration stage is disposed at the launch facility proximate the first refrigeration stage and is configured to flow a second refrigerant through a second heat exchanger to subcool the liquid oxygen stream and yield a densified, liquid oxygen stream.