A refrigeration system

Abstract

The invention discloses a refrigeration system, comprising: a generator, provided with a liquid storage chamber for containing liquid ammonia and sodium nitrate solution, the generator is connected to a heat source, and an exhaust pipe is arranged at the upper end of the generator; a condenser, provided with a condensation chamber, the inlet of the condensation chamber is connected to the exhaust pipe; an evaporator, provided with an evaporation chamber for containing hydrogen, the inlet of the evaporation chamber is connected to the outlet of the condensation chamber through a liquid inlet pipe; an absorber, located below the evaporator, the absorber has an absorption chamber for containing sodium nitrate solution, the upper end of the absorption chamber is connected to the outlet of the evaporation chamber through a mixed gas pipe, the absorber is provided with a reflux pipe, the reflux pipe is connected to the absorption chamber and the liquid storage chamber; a first cold water pipe of a lithium bromide water refrigerator is connected to the condenser to cool the gas in the condensation chamber, and a second cold water pipe is connected to the absorber to cool the sodium nitrate solution in the absorption chamber; wherein the absorber is provided with a return air pipe, the return air pipe is connected to the upper part of the absorption chamber and the evaporation chamber, and the exhaust pipe is provided with a bypass pipe connected to the return air pipe.

Description

Technical Field

[0001] The invention relates to the technical field of refrigeration, and in particular to a sodium nitrate-liquid ammonia diffusion absorption refrigeration system. Background Art

[0002] There are several common absorption refrigeration methods at present: ammonia absorption refrigeration and ammonia hydrogen water absorption diffusion refrigeration. Although the refrigeration temperature of ammonia absorption refrigeration can reach dozens of degrees below zero, because the refrigerant pair is ammonia and water, both will evaporate when heated, which not only requires the installation of a distillation device, but also reduces the refrigeration efficiency. Ammonia hydrogen water diffusion refrigeration adds a diffusion gas - hydrogen as a balance gas on the basis of ammonia absorption refrigeration. Because the refrigerant pair is still ammonia and water, the disadvantage is similar to that of ammonia absorption refrigeration. The COP is generally around 0.4, which is difficult to meet large refrigeration needs. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a refrigeration system, which uses sodium nitrate and liquid ammonia as a refrigeration working medium pair, has a low refrigeration temperature and simplifies equipment requirements.

[0004] A refrigeration system according to an embodiment of the present invention comprises: a generator having a liquid storage chamber for accommodating liquid ammonia and sodium nitrate solution, the generator being connected to a heat source, and an exhaust pipe being arranged at the upper end of the generator; a condenser having a condensation chamber, the inlet of which is connected to the exhaust pipe; an evaporator having an evaporation chamber for accommodating hydrogen, the inlet of which is connected to the outlet of the condensation chamber through a liquid inlet pipe; an absorber located below the evaporator, the absorber having an absorption chamber for accommodating sodium nitrate solution, the upper end of which is connected to the evaporator through a mixed gas pipe. The outlet of the evaporation chamber, the absorber is provided with a reflux pipe, the reflux pipe connects the absorption chamber with the liquid storage chamber; a lithium bromide water refrigerator, the cold water output end of the lithium bromide water refrigerator is provided with a first cold water pipe and a second cold water pipe, the first cold water pipe is connected to the condenser to cool the gas in the condensation chamber, and the second cold water pipe is connected to the absorber to cool the sodium nitrate solution in the absorption chamber; wherein the absorber is provided with a return air pipe, the return air pipe connects the upper part of the absorption chamber and the evaporation chamber, and the exhaust pipe is provided with a bypass pipe connected to the return air pipe.

[0005] The refrigeration system according to the embodiment of the present invention has at least the following beneficial effects: the liquid ammonia-sodium nitrate diffusion refrigeration device uses sodium nitrate as the absorbent and liquid ammonia as the refrigerant. Sodium nitrate is a salt with a boiling point of 380°C, which is very different from the boiling point of liquid ammonia. Therefore, the distillation equipment is eliminated, the system is simplified, and the cost is reduced; the constant pressure specific heat is large, which is conducive to reducing the heat exchange area, miniaturizing the equipment, and reducing the occupied space; liquid ammonia-sodium nitrate is a relatively ideal absorption refrigeration working fluid pair, and the COP can also meet higher requirements. The refrigeration can reach below zero, meet larger refrigeration needs, and provide a larger range of use.

[0006] According to some embodiments of the present invention, the heat source is a hot water pipeline, and the hot water pipeline is above 110°C.

[0007] According to some embodiments of the present invention, the condenser is provided with an inclined air inlet pipe, a lower end of the air inlet pipe is connected to the exhaust pipe, and a high end of the air inlet pipe is located inside the condensation chamber.

[0008] According to some embodiments of the present invention, the first cold water pipe is provided with a coil in the condensing chamber.

[0009] According to some embodiments of the present invention, the bypass pipe has an S-shaped pipe section, and a high end of the S-shaped pipe section is connected to the return air pipe.

[0010] According to some embodiments of the present invention, the upper end of the air return pipe is an inclined pipe arranged obliquely, and the high end of the inclined pipe is connected to the evaporation chamber.

[0011] According to some embodiments of the present invention, a bending section is provided at the lower end of the inclined tube.

[0012] According to some embodiments of the present invention, the reflux pipe is arranged at an angle, and the lower end of the reflux pipe is connected to the liquid storage chamber.

[0013] According to some embodiments of the present invention, the lithium bromide water refrigerator includes a second generator, and the second generator is connected to the heat source to achieve heating.

[0014] According to some embodiments of the present invention, the cold water output by the lithium bromide water refrigerator is 7°C to 9°C.

[0015] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0017] Figure 1Schematic diagram of the structure of the refrigeration system of some embodiments of the present invention. DETAILED DESCRIPTION

[0018] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0019] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., and orientation or state relationships indicated are based on the orientation or state relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] In the description of the present invention, if there is a description of first and second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0021] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0022] Reference Figure 1Some embodiments of the present invention provide a refrigeration system, including: a generator 100, having a liquid storage chamber 101 for accommodating liquid ammonia and sodium nitrate solution, the generator 100 is connected to a heat source 110, and an exhaust pipe 102 is arranged at the upper end of the generator 100; a condenser 200, having a condensation chamber 201, and the inlet of the condensation chamber 201 is connected to the exhaust pipe 102; an evaporator 300, having an evaporation chamber 301 for accommodating hydrogen, and the inlet of the evaporation chamber 301 is connected to the outlet of the condensation chamber 201 through a liquid inlet pipe 302; an absorber 400, located below the evaporator 300, the absorber 400 has an absorption chamber 401 for accommodating sodium nitrate solution, and the upper end of the absorption chamber 401 is connected to the exhaust pipe 102 through a mixed gas pipe 40 2 is connected to the outlet of the evaporation chamber 301, the absorber 400 is provided with a reflux pipe 403, the reflux pipe 403 is connected to the absorption chamber 401 and the liquid storage chamber 101; a lithium bromide water refrigerator 500, the cold water output end of the lithium bromide water refrigerator 500 is provided with a first cold water pipe 501 and a second cold water pipe 502, the first cold water pipe 501 is connected to the condenser 200 to cool the ammonia in the condensation chamber 201, and the second cold water pipe 502 is connected to the absorber 400 to cool the sodium nitrate solution in the absorption chamber 401; wherein the absorber 400 is provided with a return air pipe 404, the return air pipe 404 is connected to the upper part of the absorption chamber 401 and the evaporation chamber 301, and the exhaust pipe 102 is provided with a bypass pipe 103 connected to the return air pipe 404. It is understandable that the lithium bromide water refrigerator 500 is an existing technology and will not be described in detail. The lithium bromide water refrigerator 500 can produce cold water at 7° C. for cooling the condenser 200 and the absorber 400 .

[0023] Reference Figure 1The operation process of the refrigeration system is as follows: the liquid ammonia and sodium nitrate solution in the liquid storage chamber 101 are heated by the heat source 110, and the liquid ammonia is evaporated into ammonia gas by the heat. The ammonia gas moves upward through the exhaust pipe 102 and enters the condenser 200. The ammonia gas exchanges heat with the cold water in the first cold water pipe 501 in the condenser 200 and condenses into liquid ammonia. The liquid ammonia flows into the evaporation chamber 301 of the evaporator 300 through the liquid inlet pipe 302. Since the evaporation chamber 301 is full of hydrogen, the liquid ammonia encounters the hydrogen gas in the evaporation chamber and is decompressed, and evaporates into ammonia gas, while absorbing heat from the surrounding environment to achieve refrigeration; then, under the action of gravity, the ammonia gas carries part of the hydrogen gas along the mixed gas pipe 402 and enters the absorption chamber 401 of the absorber 400 The hydrogen rises along the return pipe 404 and returns to the evaporation chamber 301, and the ammonia is absorbed by the sodium nitrate solution in the absorption chamber 401. In order to ensure the ability of the sodium nitrate solution to absorb ammonia, the cold water of the second cold water pipe 502 is used to reduce the temperature of the sodium nitrate solution in the absorption chamber 401; the heat source 110 heats the liquid ammonia and sodium nitrate solution in the liquid storage chamber 101, and part of the sodium nitrate solution enters the absorption chamber 401 along the exhaust pipe 102, the bypass pipe 103, and the return pipe 404 due to the thermal siphon effect. After the sodium nitrate solution absorbs the ammonia, it enters the liquid storage chamber 101 through the reflux pipe 403. The liquid ammonia and sodium nitrate solution circulate continuously, and absorb heat at the evaporator 300 to achieve refrigeration. The refrigeration system uses sodium nitrate as the absorbent and liquid ammonia as the refrigerant. Sodium nitrate is a salt with a boiling point of 380°C, which is very different from the boiling point of liquid ammonia. Therefore, the distillation equipment is eliminated, the system is simplified, and the cost is reduced; the constant pressure specific heat is large, which is conducive to reducing the heat exchange area, miniaturizing the equipment, and reducing the occupied space; liquid ammonia-sodium nitrate is a relatively ideal absorption refrigeration working fluid pair, and the COP can also meet higher requirements. The refrigeration can reach below zero degrees, meet larger refrigeration needs, and provide a wider range of uses.

[0024] Reference Figure 1 According to some embodiments of the present invention, the heat source 110 is a hot water pipeline, and the hot water pipeline is above 110°C. For example, an oil refinery in the petrochemical industry can produce a large amount of 120°C steam condensate per hour. At the same time, the dewaxing process of the oil refinery requires refrigeration, and the refrigeration temperature is -40°C and -20°C. The refrigeration system of the present invention can be used.

[0025] Reference Figure 1 According to some embodiments of the present invention, the condenser 200 is provided with an inclined air inlet pipe, the lower end of the air inlet pipe is connected to the exhaust pipe 102, and the upper end of the air inlet pipe is located inside the condensation chamber 201. The inclined air inlet pipe can make the ammonia gather and fill the air inlet pipe, slow down the flow rate, and help the cooling process of the ammonia in the condensation chamber 201.

[0026] Reference Figure 1 According to some embodiments of the present invention, the first cold water pipe 501 is provided with a coil in the condensing chamber 201 to increase the contact area and improve the cooling capacity of the ammonia gas.

[0027] Reference Figure 1 According to some embodiments of the present invention, the bypass pipe 103 has an S-shaped pipe section, and the high end of the S-shaped pipe section is connected to the gas return pipe 404. The S-shaped pipe section is conducive to the discharge of ammonia in the pipe, reducing the ammonia being brought into the absorption chamber 401.

[0028] Reference Figure 1 According to some embodiments of the present invention, the upper end of the return air pipe 404 is an inclined pipe arranged obliquely, and the high end of the inclined pipe is connected to the evaporation chamber 301.

[0029] Reference Figure 1 According to some embodiments of the present invention, a bending section is provided at the lower end of the inclined tube.

[0030] Reference Figure 1 According to some embodiments of the present invention, the reflux pipe 403 is inclined, and the lower end of the reflux pipe 403 is connected to the liquid storage chamber 101, and gravity is used to allow the sodium nitrate solution that has absorbed ammonia to automatically flow into the liquid storage chamber 101.

[0031] Reference Figure 1 According to some embodiments of the present invention, the lithium bromide water refrigerator 500 includes a second generator 510, and the second generator 510 is connected to the heat source 110 to achieve heating. The second generator 510 and the generator 100 use a common heat source, which simplifies the structure and improves efficiency.

[0032] Reference Figure 1 According to some embodiments of the present invention, the cold water output by the lithium bromide water refrigerator 500 is 7°C to 9°C.

[0033] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A refrigeration system, characterized in that: include: A generator having a liquid storage chamber for containing liquid ammonia and sodium nitrate solution, the generator being connected to a heat source, and an exhaust pipe being arranged at the upper end of the generator; A condenser having a condensation chamber, an inlet of the condensation chamber being connected to the exhaust pipe, the condenser being provided with an inclined air inlet pipe, a lower end of the air inlet pipe being connected to the exhaust pipe, and a high end of the air inlet pipe being located inside the condensation chamber; An evaporator having an evaporation chamber for containing hydrogen, wherein the inlet of the evaporation chamber is connected to the outlet of the condensation chamber through a liquid inlet pipe; An absorber is located below the evaporator, the absorber has an absorption chamber for accommodating sodium nitrate solution, the upper end of the absorption chamber is connected to the outlet of the evaporation chamber through a mixed gas pipe, the absorber is provided with a reflux pipe, the reflux pipe connects the absorption chamber and the liquid storage chamber, the reflux pipe is inclined, and the lower end of the reflux pipe is connected to the liquid storage chamber; A lithium bromide water refrigerator, wherein a first cold water pipe and a second cold water pipe are provided at a cold water output end of the lithium bromide water refrigerator, wherein the first cold water pipe is connected to the condenser to cool the ammonia in the condensation chamber, and the second cold water pipe is connected to the absorber to cool the sodium nitrate solution in the absorption chamber; The absorber is provided with a return air pipe, the return air pipe is connected with the upper part of the absorption chamber and the evaporation chamber, and the exhaust pipe is provided with a bypass pipe connected with the return air pipe.

2. A refrigeration system according to claim 1, characterized in that: The heat source is a hot water pipeline, and the hot water pipeline is above 110°C.

3. A refrigeration system according to claim 1, characterized in that: The first cold water pipe is provided with a coil in the condensing chamber.

4. A refrigeration system according to claim 1, characterized in that: The bypass pipe has an S-shaped pipe section, and the high end of the S-shaped pipe section is connected to the return air pipe.

5. A refrigeration system according to claim 4, characterized in that: The upper end of the air return pipe is an inclined pipe arranged obliquely, and the high end of the inclined pipe is connected to the evaporation chamber.

6. A refrigeration system according to claim 5, characterized in that: The lower end of the inclined tube is provided with a bending section.

7. A refrigeration system according to claim 1, characterized in that: The lithium bromide water refrigerator comprises a second generator, and the second generator is connected to the heat source to achieve heating.

8. A refrigeration system according to claim 7, characterized in that: The cold water output by the lithium bromide water refrigerator is 7°C to 9°C.

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