MXPA00011915A - Cryogenic ultra cold hybrid liquefier - Google Patents

Abstract

A system for effectively generating refrigeration for use in putting a product fluid into an ultra cold condition wherein an active magnetic regenerator or a multicomponent refrigerant fluid cycle is integrated with a pulse tube system for receiving heat generated by the pulse tube system.

Description

HYBRID CRYOGENIC LYE REFINER. ULTRA-COLD TECHNICAL FIELD This invention relates generally to refrigeration and, more particularly, to the generation of refrigeration, such as to liquefy gases, such as hydrogen, which require ultra-cold temperatures to liquefy.

THE BACKGROUND TECHNIQUE The liquefaction of certain gases, such as neon, hydrogen or helium, requires the generation of refrigeration at a very low temperature. For example, at atmospheric pressure, the neon liquefies at 27.TK; the hydrogen liquefies at 20.39 ° K and the helium liquefies at 4.21 ° K. The generation of said refrigeration at very low temperature is very expensive. To the extent that the use of fluids such as neon, hydrogen and helium is becoming increasingly important in fields such as power generation, power transmission and electronics, any improvement in the systems for the liquefaction of such fluids would be very convenient . Pulsed tube refrigeration, where refrigeration is generated by a pressure pulse applied to a gas, is used to liquefy fluids such as neon, hydrogen and helium; but such use is only effective on a very small scale. Accordingly, it is an object of this invention to provide an improved system for generating sufficient cooling to liquefy fluids difficult to liquefy, such as neon, hydrogen or helium. It is another object of the invention to provide a system for liquefying liquids difficult to liquify, such as neon, hydrogen or helium, which can operate at a relatively high level of production.

BRIEF DESCRIPTION OF THE INVENTION The above objectives and others that will become apparent to those skilled in the art, when reading this description are obtained by the present invention, one of whose aspects is: A method to produce a fluid product in an ultra condition -Fria, which comprises: (A) compressing a multicomponent refrigerant fluid; cooling the compressed multiple component refrigerant fluid to produce cooled multiple component refrigerant fluid; and expanding the cold multi-component refrigerant fluid to at least partially condense the multicomponent refrigerant fluid; (B) compressing pulse tube gas to produce pulse tube gas, compressed; cool the tube gas for pulse, compressed, hot by indirect heat change with the. at least partially condensed multi-component refrigerant fluid, to produce compressed, cooled pulse tube gas, and heated multi-component refrigerant fluid; and further cooling the pulse tube gas, compressed, cooled, by direct contact with cold heat transfer means, to produce pulse tube gas, cold; and heated heat transfer means; (C) expand the cold pulse tube gas to produce ultra-cold pulse tube gas and produce a gas pressure wave that compresses and heats the working fluid of pulse tube and cool the pulse tube work, hot, by indirect heat exchange with the hot, multi-component refrigerant fluid to produce additionally heated multi-component refrigerant fluid; and (D) passing the ultra-cold pulse tube gas in indirect heat exchange relationship with the product fluid to produce product fluid in ultra-cold condition; and then passing the resulting pulse tube gas in direct contact with heated heat transfer means, to produce the cold heat transfer means. Another aspect of the invention is: An apparatus for producing product fluid in an ultra-cold condition, comprising: (A) a compressor, a heat exchanger for multicomponent refrigerant fluid; means for passing the fluid from the compressor to the heat exchanger for multicomponent refrigerant fluid; an expansion device and means for passing fluid from the multicomponent refrigerant heat exchanger to the expansion device; (B) a regenerator comprising a regenerator heat exchanger and a regenerator body containing heat transfer means, means for generating pressurized gas to oscillate the flow within the regenerator; and means for passing fluid from the expansion device to the heat exchanger of the regenerator; (C) a pulse tube, comprising a pulse tube heat exchanger and a pulse tube body; means for passing fluid from the heat exchanger of the regenerator to the heat exchanger of the pulse tube; and means for passing fluid from the heat exchanger of the pulse tube to the heat exchanger of the multicomponent refrigerant fluid; and (D) passage means for passing gas between the regenerator body and the body of the pulse tube; including the passage means a heat exchanger for fluid product; means for providing product fluid to the product fluid heat exchanger, and means for extracting the product fluid from the product fluid heat exchanger, in an ultra-cold condition. As used herein, the term "multicomponent refrigerant fluid" means a fluid that comprises two or more species, and that is capable of generating refrigeration. As used herein, the term "variable charge refrigerant" means a mixture of two or more components in such proportions, that the liquid phase of those components undergoes a continuous and increasing temperature change between the bubble point and the dew point. mix. The bubble point of the mixture is the temperature, at a given pressure, at which the mixture is fully in the liquid phase, but the addition of heat will initiate the formation of a vapor phase in equilibrium with the liquid phase. The dew point of the mixture is the temperature, at a given pressure, at which the mixture is all in the vapor phase, but the extraction of heat will initiate the formation of a liquid phase in equilibrium with the vapor phase. Therefore, the region of temperature between the bubble point and the dew point of the mixture is the region in which the liquid and vapor phases co-exist in equilibrium at the same time. In the practice of this invention the temperature differences between the bubble point and the dew point for the variable charge refrigerant is at least 10 ° K, preferably at least 20 ° K and, most preferably, at least minus 50 ° K. As used herein, the term "ultra-cold condition" means a temperature of 90 ° K or less. As used herein, the term "indirect heat change" means bringing the fluids to a heat exchange rate, without any physical contact or mixing of the fluids with each other. As used here, e! term "expansion" means to make a reduction in pressure. As used herein, the term "atmospheric gas" means one of the following: nitrogen (N2), argon (Ar), krypton (Kr), xenon (Xe), neon (Ne), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), deuterium (D2), hydrogen (H2) and helium (He).

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic representation of a preferred embodiment of the invention, wherein a multi-component cooling fluid cooling system is integrated with a pulse tube cooling system. Figure 2 is a schematic representation of another embodiment of the invention, wherein a cooling system with active magnetic regenerator is integrated with a pulse tube cooling system.

DETAILED DESCRIPTION In general the invention comprises the generation of cooling at very cold temperatures, using a pulseless tube system, which is preferably a multi-component cooling fluid cooling system or a cooling system with active magnetic regenerator. The pulseless tube system is integrated with the pulse tube system in a defined manner, so that the heat generated by the pulse tube system is rejected into the pulseless tube system, which allows the system to Pulse tube effectively generates ultra-cool refrigeration to carry a relatively large amount of fluid product, to an ultra-cold condition.

The invention will be described in more detail with reference to the drawings. Referring now to Figure 1, a multicomponent refrigerant fluid, in stream 310 is compressed in compressor 311 at a pressure generally within the range of 413.6 kPa to 6,894.7 kPa Absolute. The multicomponent refrigerant fluid in the practice of this invention comprises at least one atmospheric gas, preferably nitrogen, argon and / or neon; and preferably at least one fluorine-containing compound, having up to four carbon atoms, such as fluorocarbons, hydrofluorocarbons, hydrochlorofluorocarbons and fluoroethers, and / or at least one hydrocarbon having up to three carbon atoms. The compressed, multi-component refrigerant fluid 312 is then cooled from the heat of compression in the cooler 313, by indirect heat exchange with a suitable cooling fluid, such as cooling water, and the multi-component refrigerant fluid is passed through. , resulting, through the heat exchanger 301, for multicomponent refrigerant fluid, where it is cooled by indirect heat exchange with the heated multi-component refrigerant fluid, as will be described further below. The cooled, multi-component refrigerant fluid 315 is passed to the expansion device 316, which is preferably an expansion valve, where it is throttled at a lower pressure, thereby lowering its temperature. The reduction of temperature in the multicomponent refrigerant fluid, as a consequence of this expansion in the expansion device 316, serves to at least partially condense, and preferably serves to completely condense the multicomponent refrigerant fluid. This multi-component refrigerant fluid is passed through line 317 to regenerator heat exchanger 258, which is located at the hot end of regenerator 252. Regenerator 252 contains pulse tube gas which may be helium, hydrogen, neon, a mixture of helium and neon or a mixture of helium and hydrogen. Helium and mixtures of helium and hydrogen are preferred. A pulse, i.e., a compression force, is applied to the hot end of the regenerator 252, as representatively illustrated by the pulse arrow 10, whereby the first part of the pulse tube sequence is initiated. . The pulse is preferably provided by a piston which compresses a gas reservoir of pulse tube in fluid communication with the regenerator 252. Another preferred means for applying the pulse to the regenerator is by the use of a thermoacoustic actuator which applies sonic energy to the regenerator. gas, inside the regenerator. Another way to apply the pulse is by means of a linear motor / compressor device. The pulse serves to compress gas from pulse tube, producing hot pulse tube gas at the hot end of the regenerator 252. The hot pulse tube gas is cooled by indirect heat exchange with the at least partially condensed multi-component refrigerant found in the exchanger 258, to produce hot multicomponent refrigerant fluid in stream 318, and to produce compressed, cooled pulse tube gas to pass it through the rest of the regenerator, i.e., the regenerator body. Some pulse tubes use a double-entry geometry, where some of the pulse gas is also sent to the hot end of the pulse tube. The body of the regenerator contains means for heat transfer. Examples of suitable heat transfer media, in the practice of this invention, include steel spheres, wire mesh, high density honeycomb structures, expanded metals and lead spheres. The heat transfer means are at a cold temperature, generally within the range of 2K to 250K, and have been brought to that cold temperature in a second part of the pulse tube sequence, which will be described more fully below. As the compressed and cooled pulse tube gas passes through the body of the regenerator, it is further cooled by direct contact with the cold heat transfer means, to produce heated heat transfer means and cold pulse tube gas, generally at a temperature within the range of 4 ° K to 252 ° K. The cold pulse tube gas is passed through line 11 to pulse tube 253 at the cold end. The pulse tube 263 has a pulse tube heat exchanger 259 at the other end, that is, the hot end, from which the cold pulse tube gas is passed, towards the pulse tube. When the cold pulse tube gas passes into the pulse tube 253, at the cold end, it expands, lowering its temperature, to form an ultra-cold pulse tube gas, and also generating a pressure wave of gas flowing to the hot end of the pulse tube 253, and compressing the gas that is inside the pulse tube, called working fluid of the pulse tube, thereby heating the working fluid of the pulse tube. The heated multi-component refrigerant fluid is passed, through line 318, to the heat exchanger 259 of the pulse tube at the hot end of the pulse tube 253. In the practice of this invention the body of the pulse tube contains only gas for the transfer of the pressure energy from the gas of the pulse tube that expands, at the cold end, to heat the working fluid of the pulse tube, at the hot end of the pulse tube. That is, the pulse tube 253 does not contain moving parts, such as those used with a piston device. The operation of the pulse tube, without moving parts, is an important advantage of this invention. The hot, multiple component refrigerant fluid is further heated by indirect heat change in the pulse tube heat exchanger 259 with the hot pulse tube working fluid to produce additionally heated multi-component refrigerant fluid. which is entirely in gaseous state and which is passed from the heat exchanger 259 of the pulse tube, by line 319, to the heat exchanger 301 of multicomponent refrigerant fluid. Within the heat exchanger 301 for multicomponent refrigerant fluid, the multicomponent refrigerant fluid is further heated by indirect heat exchange with the multicomponent refrigerant fluid, which is cooled, brought to the heat exchanger 301 in stream 314 , as discussed previously, and resulting in an additionally heated multi-component refrigerant fluid, which is passed from the heat exchanger 301 through line 310, to the compressor 311, and the cooling cycle of the multi-component refrigerant fluid is started again. Fixed to the hot end of the pulse tube 253, there is a line having the orifice 257 leading to the reservoir 254. The compression wave of the working fluid in the pulse tube makes contact with the hot end wall of the pulse tube and returns in the second part of the pulse tube sequence. The orifice 257 and the reservoir 254 are employed to maintain this compression wave in phase so as not to interfere with the next compression wave generated by the cold, expanding, pulse tube gas at the cold end of the tube. pulse 253. The ultra-cold pulse tube gas at the cold end of the pulse tube 253 passes again through line 11, to the regenerator 252. On this return path, the ultra-cold pulse tube gas passes through the heat exchanger 255 of the product fluid, in line 12. Among the fluids products that can be cooled, liquefied and / or subcooled in the practice of the present invention, can be mentioned: hydrogen, deuterium, helium, neon, nitrogen, argon and mixtures comprising one or more of them. As the product fluid passes through the heat exchanger 255 for product fluid, it is brought to an ultra-cold condition by indirect heat change with the ultra-cold pulse tube gas. The resulting product fluid, which is in an ultra-cold condition, and may be in gaseous, liquid or mixed gas-liquid form, is extracted from the heat exchanger 255 for product fluid, and recovered. The pulse tube gas that comes out of the heat exchanger 255 for product fluid is passed through line 11 to regenerator 252, where it makes contact directly with the heat transfer means within the body of the regenerator, to produce the above-mentioned cold heat transfer means, completing that the second part of the pulse tube refrigerant sequence, and placing the regenerator in condition for the first part of a pulse tube cooling sequence, subsequent. Figure 2 illustrates another embodiment of the invention in which the heat generated by the cooling system of the pulse tube is rejected towards a cooling system by active magnetic regenerator, which is integrated with the pulse tube cooling system. The numbers in Figure 2 are the same as those in Figure 1 for the common elements, and these common elements will not be discussed here again, in detail. Referring now to Figure 2, the hot coolant fluid from the stream 320 is passed through the pump 321 and then as the stream 322 passed to the cooler 323, where it is cooled to form the cooled coolant 324. The active magnetic regenerator 302 comprises a bed material, which is heated with magnetization and cooled when demagnetized. The regenerator 302 is demagnetized and the cooling fluid from the stream 324 passes through the heat exchanger portion of the regenerator 302 in the process of being cooled by the heat exchanger with the demagnetized bed material. The resulting cooled cooling fluid in stream 325 is then heated and further heated through the pulse tube system, as previously described, and the hot coolant fluid is passed, resulting again to the active magnetic regenerator. 302, which has been magnetized, thereby further heating the refrigerant fluid. The refrigerant fluid leaves the regenerator 302 in stream 320 and the cycle starts again. While the invention has been described in detail, with reference to certain preferred embodiments, those skilled in the art will recognize that there are other embodiments of the invention within the spirit and scope of the claims.

Claims (10)

1. - Method for producing a product fluid in an ultra-cold condition, characterized in that it comprises: (A) compressing a multicomponent refrigerant fluid; cooling the compressed multiple component refrigerant fluid to produce a cooled, multi-component refrigerant fluid; and expanding the cooled multiple component refrigerant fluid, to at least partially condensate the multicomponent refrigerant fluid; (B) compress a pulse tube gas, to produce hot, compressed pulse tube gas; cooling the hot, compressed pulse tube gas, by indirect heat exchange with the at least partially condensed, multiple component refrigerant fluid, to produce compressed, cooled pulse tube gas, and heated multi-component refrigerant fluid; and further cooling the compressed, compressed pulse tube gas, by direct contact with cold heat transfer means, to produce cold pulse tube gas and hot heat transfer means; (C) expanding the cold pulse tube gas to produce ultra-cold pulse tube gas, and to produce a gas pressure wave that compresses and heats the working fluid of the pulse tube; and cooling the working fluid of the hot pulse tube, by indirect heat change, with the hot, multi-component refrigerant fluid to produce additionally heated multi-component refrigerant fluid; and (D) passing the ultra-cold pulse tube gas, indirectly heat exchange with the product fluid, to produce product fluid in an ultra-cold condition; and then passing the resulting pulse tube gas, in direct contact with the heated heat transfer media, to produce the cold heat transfer means.

2. The method according to claim 1, further characterized in that the expanded, multi-component refrigerant fluid is completely condensed.

3. The method according to claim 1, further characterized in that the multi-component cooling fluid comprises at least one atmospheric gas.

4. The method according to claim 1, further characterized in that the multi-component refrigerant fluid is a variable charge refrigerant.

5. Apparatus for producing product fluid in an ultra-cold condition, characterized in that it comprises: (A) a compressor; a heat exchanger for multicomponent refrigerant fluid; means for making fluid from the compressor to the heat exchanger for multicomponent refrigerant fluid; an expansion device, and means for passing fluid from the heat exchanger for multicomponent refrigerant fluid to the expansion device; ^ U ^ ^ (B) a regenerator comprising a regenerator heat exchanger and a regenerator body containing heat transfer means; means for generating pressurized gas for oscillating flow within the regenerator, and means for passing fluid from the expansion device to the regenerator's heat exchanger; (C) a pulse tube, comprising a tube heat exchanger for pulses and a tube body for pulses; means for passing fluid from the heat exchanger of the regenerator to the heat exchanger of the pulse tube; and means for passing fluid from the pulse tube heat exchanger to the heat exchanger for multicomponent refrigerant fluid; and (D) passage means for passing gas between the body of the regenerator and the body of the pulse tube; said passage means including a heat exchanger for product fluid; means for supplying product fluid to the heat exchanger for product fluid and means for extracting product fluid from the heat exchanger for fluid product, in an ultra-cold condition.

6. The apparatus according to claim 1, further characterized in that the expansion device is a valve.

7. The apparatus according to claim 5, further characterized in that the means for generating pressurized gas for flow within the regenerator comprises a piston.

8. The apparatus according to claim 5, further characterized in that the means for generating pressurized gas for flow within the regenerator comprises a thermoacoustic actuator.

9. Method for producing product fluid in an ultra-cold condition, characterized in that it comprises: (A) cooling refrigerant fluid to produce cooled refrigerant fluid; (B) compress gas from pulse tube, to produce hot, compressed pulse tube gas; cooling the hot, compressed pulse tube gas, by indirect heat exchange with the cooled refrigerant fluid, to produce compressed, cooled, compressed pulse tube gas and hot coolant fluid; and further cooling the cooled, compressed pulse tube gas, by direct contact with cold heat transfer means, to produce cold pulse tube gas and hot heat transfer means; (C) expand the cold pulse tube gas to produce ultra-cold pulse tube gas, and to produce a gas pressure wave that compresses and heats the working fluid of the pulse tube, and to cool the working fluid of the hot pulse tube, by indirect heat exchange with the heated refrigerant fluid, to produce additionally heated refrigerant fluid; and (D) passing the ultra-cold pulse tube gas, instead of indirect heat with the product fluid, to produce product fluid in an ultra-cold condition; and then passing the resultant pulse tube gas in direct contact with the heated heat transfer means to produce the cooled heat transfer means.

10. Apparatus for producing product fluid in an ultra-cold condition, characterized in that it comprises: (A) a heat exchanger for cooling fluid, and means for passing refrigerant fluid to the heat exchanger for cooling fluid; (B) a regenerator comprising a regenerator heat exchanger and a regenerator body containing heat transfer means; means for generating pressurized gas for oscillating flow with the regenerator; and means for passing the refrigerant fluid from the heat exchanger for cooling fluid to the heat exchanger of the regenerator; (C) a pulse tube comprising a pulse tube heat exchanger and a pulse tube body; means for passing coolant fluid from the heat exchanger of the regenerator to the heat exchanger of the pulse tube, and means for passing coolant fluid from the pulse tube heat exchanger to the coolant heat exchanger; and (D) passage means for passing gas between the body of the regenerator and the body of the pulse tube; the passage means including a heat exchanger for product fluid, means for supplying the product fluid to the heat exchanger for product fluid and means for extracting the product fluid from the heat exchanger for product fluid, in an ultra-cold condition.