Abstract: A refrigerator 1 of the present disclosure includes: at least two compressors, namely, a low-stage compressor C1 and a high-stage compressor C3; an expander T; a cooling part 2 for cooling a cooling object R2 with a refrigerant R1 expanded by the expander T; a refrigerant circulation line 8 for circulating the refrigerant; a bypass line 31 connected to a high-pressure line and a low-pressure line of the refrigerant circulation line 8; a bypass valve 32; a first temperature sensor 33 for detecting a temperature of the refrigerant R1 on an inlet side of the expander T or a second temperature sensor 34 for detecting the temperature of the refrigerant R1 on an outlet side of the expander T; and a controller 40 for controlling an opening degree of the bypass valve 32 and a rotation speed of the refrigerator 1 based on a detection result of the first temperature sensor 33 or the second temperature sensor 34.

Abstract: A refrigerator according to the present invention includes: a cooling part for cooling an object to be cooled through heat exchange with a refrigerant; an expander-integrated compressor including a compressor for compressing the refrigerant and an expander for expanding the refrigerant integrated therein; and a refrigerant circulation line configured to circulate the refrigerant through the compressor, the expander, and the cooling part. The compressor includes a low-stage compressor, a middle-stage compressor, and a high-stage compressor disposed in series in the refrigerant circulation line.

Abstract: To provide a refrigeration system capable of being installed efficiently in a limited space while ensuring a good reliability, the refrigeration system according to the present invention comprises a refrigeration cycle having: a circulation path (101) in which a refrigerant flows; and at least one compressor (102) for compressing the refrigerant, a heat exchanger (103) for cooling the refrigerant compressed by the compressor, at least one expansion turbine (104) for expanding the refrigerant cooled by the heat exchanger to generate cold heat, and a cooling part (105) for cooling an object to be cooled by the cold heat, which are provided on the circulation path in order, wherein at least either the at least one compressor or the at least one expansion turbine comprises a plurality of compressors or expansion turbines which are arranged in parallel with one another with respect to the circulation path.

Abstract: An expander-integrated compressor is provided and includes: a motor; a compressor connected to an output shaft of the motor; an expander connected to the output shaft of the motor; a non-contact bearing disposed between the compressor and the expander; a casing; and an extraction line being in communicated with a region between the compressor and the expander in the internal space of the casing and extracts, from the region, the leakage fluid from the compressor side toward the expander side in the casing and to send the leakage fluid to a fluid line connected to the intake side or the discharge side of the compressor outside the casing. The casing seals the region from outside of the casing, thus the flow of the at least a part of the leakage fluid through the extraction line is the only flow of fluid between the region and the outside of the casing.

Abstract: A refrigerator according to the present invention includes: a cooling part for cooling an object to be cooled through heat exchange with a refrigerant; an expander-integrated compressor including a compressor for compressing the refrigerant and an expander for expanding the refrigerant integrated therein; and a refrigerant circulation line configured to circulate the refrigerant through the compressor, the expander, and the cooling part. The compressor includes a low-stage compressor, a middle-stage compressor, and a high-stage compressor disposed in series in the refrigerant circulation line.

Abstract: A Brayton cycle type refrigerating apparatus using multiple stages of compressors and having a good response without reduction in efficiency due to change in heat load of the object to be cooled is provided. The Brayton cycle type refrigerating apparatus includes on a refrigerant line on which multiple stages of compressors are arranged in series. The apparatus also includes a temperature sensor for detecting heat load of an object to be cooled and a buffer tank provided between a low pressure line and a high pressure line. A flow rate of the refrigerant in the refrigerant line is controlled by controlling opening degrees of valves to adjust the cooling capacity.

Abstract: An expander-integrated compressor is provided and includes: a motor; a compressor connected to an output shaft of the motor; an expander connected to the output shaft of the motor; a non-contact bearing disposed between the compressor and the expander; a casing; and an extraction line being in communicated with a region between the compressor and the expander in the internal space of the casing and extracts, from the region, the leakage fluid from the compressor side toward the expander side in the casing and to send the leakage fluid to a fluid line connected to the intake side or the discharge side of the compressor outside the casing. The casing seals the region from outside of the casing, thus the flow of the at least a part of the leakage fluid through the extraction line is the only flow of fluid between the region and the outside of the casing.

Abstract: To provide a refrigeration system capable of being installed efficiently in a limited space while ensuring a good reliability, the refrigeration system according to the present invention comprises a refrigeration cycle having: a circulation path (101) in which a refrigerant flows; and at least one compressor (102) for compressing the refrigerant, a heat exchanger (103) for cooling the refrigerant compressed by the compressor, at least one expansion turbine (104) for expanding the refrigerant cooled by the heat exchanger to generate cold heat, and a cooling part (105) for cooling an object to be cooled by the cold heat, which are provided on the circulation path in order, wherein at least either the at least one compressor or the at least one expansion turbine comprises a plurality of compressors or expansion turbines which are arranged in parallel with one another with respect to the circulation path.

Abstract: To provide a Brayton cycle type refrigerating apparatus using multiple stages of compressors and having a good response without reduction in efficiency due to change in heat load of the object to be cooled, the Brayton cycle type refrigerating apparatus (100) according to the present invention comprises, on a refrigerant line (101), multiple stages of compressors (102a, 102b, 102c), a temperature sensor (160) for detecting heat load of an object to be cooled, and a buffer tank (111) provided between a low pressure line (109) and a high pressure line (110), wherein a flow rate of the refrigerant in the refrigerant line is controlled by controlling opening degrees of valves (112, 113) to adjust the cooling capacity.

Abstract: A system for utilizing coal energy includes a thermal power generator near a coal field area that converts coal energy of the coal field area located remotely from a demand end to electric energy. It also includes an alternating current load at a demand end side, an alternating current power distribution network, and an electric power transmission mechanism that transmit electric energy from the thermal power generator to the power distribution network. The electric power transmission mechanism is a combination of super conductive power transmitting system that transmit direct current electricity with small transmission loss utilizing super conductive power transmitting cables and a conventional power distribution network operating at ambient temperatures.

Abstract: An apparatus for producing a slush fluid wherein a liquid and solid particles are mixed together, comprising product tank (1) for storing the slush fluid (50) in its saturated condition; liquid nitrogen supply nozzle (10) provided at an upper part of the product tank (1); and compressor (15) for evacuating the interior of the product tank, which apparatus is adapted to spray a liquid in microparticulate form through the liquid nitrogen supply nozzle (10) into the product tank evacuated by the compressor (15) and to solidify the liquid particles by evaporative latent heat, thereby forming solid nitrogen (51).

Abstract: Cryogenic liquefying/refrigerating method and system, wherein temperature of gas-to-be-liquefied at the inlet of the compressor for compressing the gas is reduced by cooling the gas discharged from the compressor using a high-efficiency chemical refrigerating machine and vapor compression refrigerating machine before the gas is introduced to a multiple stage heat exchanger thereby reducing power input to the compressor and improving liquefying/refrigerating efficiency.

Abstract: A method for producing slush nitrogen comprises the steps of: spraying liquid nitrogen from a nozzle into a vessel kept under a reduced pressure with a nozzle diameter and a spraying pressure being so adjusted as for the liquid nitrogen to maintain the form of droplets, to thereby form liquid nitrogen fine particles having a uniform particle diameter and disperse said particles in the vessel; vaporizing nitrogen from the droplet particles during the stay thereof in the space of the vessel, to solidify liquid nitrogen particles by vaporization latent heat and form fine solid nitrogen particles having a uniform particle diameter; and mixing the solid nitrogen particles with liquid nitrogen.

Abstract: Liquid nitrogen is filled in a low temperature vessel; an ejector that sucks liquid nitrogen by blowing a cooling agent (liquid or gas) such as low temperature helium gas or liquid helium of pressure higher than in the space within the vessel is disposed in the vessel; the liquid nitrogen blown with the cooling agent is cooled by the cooling agent to become fine particles of solid nitrogen which fall down; and gas in a space of the vessel is discharged out of the vessel so as to maintain the pressure of the space higher than the atmospheric pressure. A gaseous phase of liquid nitrogen in an adiabatic vessel is depressurized to vaporize nitrogen in a liquid phase so that the temperature of the nitrogen reaches the triple point of nitrogen by lowering the temperature to thereby produce solid nitrogen by keeping the temperature at the triple point, and that the produced solid nitrogen is transformed into slush by stirring the content of the adiabatic vessel.

Abstract: An apparatus for producing a slush fluid wherein a liquid and solid particles are mixed together, comprising product tank (1) for storing the slush fluid (50) in its saturated condition; liquid nitrogen supply nozzle (10) provided at an upper part of the product tank (1); and compressor (15) for evacuating the interior of the product tank, which apparatus is adapted to spray a liquid in microparticulate form through the liquid nitrogen supply nozzle (10) into the product tank evacuated by the compressor (15) and to solidify the liquid particles by evaporative latent heat, thereby forming solid nitrogen (51).

Abstract: In order to provide a thermo-siphon chiller refrigerator for use in cold districts which performs natural refrigerant-circulation refrigerating cycle and also can perform a forced refrigerant-circulation refrigerating cycle when outside air temperature is high by using an indoor heat exchanger, an outdoor heat exchanger, and a compressor, and combining them with refrigerant piping, the thermo-siphon chiller refrigerator for use in cold districts of the invention has a compressor (10) additionally installed to a natural refrigerant-circulation refrigerating system comprising an outdoor heat exchanger (12), an indoor heat exchanger (11) located at a position lower than that of the outer heat exchanger (12), and an expansion valve (18). When the refrigerating capacity of the natural refrigerant-circulation refrigerating system is not sufficient, the additional compressor (10) is operated to perform a forced refrigerant-circulation cycle i.e. a vapor compression refrigerating cycle.

Abstract: Cryogenic liquefying/refrigerating method and system, wherein temperature of gas-to-be-liquefied at the inlet of the compressor for compressing the gas is reduced by cooling the gas discharged from the compressor using a high-efficiency chemical refrigerating machine and vapor compression refrigerating machine before the gas is introduced to a multiple stage heat exchanger thereby reducing power input to the compressor and improving liquefying/refrigerating efficiency.

Abstract: Liquid nitrogen is filled in a low temperature vessel; an ejector that sucks liquid nitrogen by blowing a cooling agent (liquid or gas) such as low temperature helium gas or liquid helium of pressure higher than in the space within the vessel is disposed in the vessel; the liquid nitrogen blown with the cooling agent is cooled by the cooling agent to become fine particles of solid nitrogen which fall down; and gas in a space of the vessel is discharged out of the vessel so as to maintain the pressure of the space higher than the atmospheric pressure. A gaseous phase of liquid nitrogen in an adiabatic vessel is depressurized to vaporize nitrogen in a liquid phase so that the temperature of the nitrogen reaches the triple point of nitrogen by lowering the temperature to thereby produce solid nitrogen by keeping the temperature at the triple point, and that the produced solid nitrogen is transformed into slush by stirring the content of the adiabatic vessel.

Abstract: Liquid nitrogen is filled in a low temperature vessel; an ejector that sucks liquid nitrogen by blowing a cooling agent (liquid or gas) such as low temperature helium gas or liquid helium of pressure higher than in the space within the vessel is disposed in the vessel; the liquid nitrogen blown with the cooling agent is cooled by the cooling agent to become fine particles of solid nitrogen which fall down; and gas in a space of the vessel is discharged out of the vessel so as to maintain the pressure of the space higher than the atmospheric pressure. A gaseous phase of liquid nitrogen in an adiabatic vessel is depressurized to vaporize nitrogen in a liquid phase so that a temperature of the nitrogen is reached to the triple point of nitrogen by lowering temperature thereby and solid nitrogen is produced by keeping at the triple point, and that the produced solid nitrogen is transformed into slush by stirring the content of the adiabatic vessel.

Abstract: A method for producing slush nitrogen comprises the steps of: spraying liquid nitrogen from a nozzle into a vessel kept under a reduced pressure with a nozzle diameter and a spraying pressure being so adjusted as for the liquid nitrogen to maintain the form of droplets, to thereby form liquid nitrogen fine particles having a uniform particle diameter and disperse said particles in the vessel; vaporizing nitrogen from the droplet particles during the stay thereof in the space of the vessel, to solidify liquid nitrogen particles by vaporization latent heat and form fine solid nitrogen particles having a uniform particle diameter; and mixing the solid nitrogen particles with liquid nitrogen.