Composite generator and absorption refrigeration system thereof

Abstract

The present application belongs to the field of refrigeration technology, and particularly relates to a composite generator and an absorption refrigeration system thereof. The composite generator comprises a generator body, a gas pocket and a liquid pocket are respectively arranged at the upper end and the lower end of the generator body, the gas pocket is arranged on the gaseous refrigerant outlet of the generator body, and the liquid pocket is arranged on the rich liquid inlet of the generator body. The composite generator can remove the liquid foam entrained in the resolved gaseous refrigerant, recycle part of the heat contained in the gaseous refrigerant, improve the evaporation efficiency of the evaporator, reduce the cooling capacity required by the condenser, use the high-pressure energy of the high-temperature and high-pressure lean liquid generated by the generator to pressurize the heat source entering the generator, improve the energy utilization rate of the unit, introduce the waste heat from the generator into the generator again, and preheat the rich liquid entering the generator, so as to improve the performance of the unit.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration technology, and specifically relates to a composite generator and its absorption refrigeration system. Background Technology

[0002] Currently, the generators in absorption chiller units mostly adopt the structure of a reboiler (BKU) (e.g.) Figure 1 As shown, a gas-liquid separation element (baffle plate, wire mesh demister) is installed inside the gas chamber on the reactor body to separate the gaseous refrigerant released from the reactor body. However, in actual operation, this gas-liquid separation is not ideal; the released gaseous refrigerant still contains liquid droplets, which enter the evaporator downstream, affecting its evaporation efficiency and reducing the unit's cooling efficiency. Furthermore, the gaseous refrigerant released from the reactor body has a high temperature, requiring a large amount of cooling energy for condensation if it enters the condenser directly. Therefore, a solution is needed to completely remove the liquid droplets entrained in the released gaseous refrigerant while recovering some of the heat contained in the released gas. This would improve the evaporator's evaporation efficiency and reduce the cooling energy required by the condenser, thereby improving the unit's operating efficiency.

[0003] Existing absorption refrigeration systems (such as) Figure 2 As shown, a solution heat exchanger (GAX) is installed between the generator and the absorber to exchange heat with the high-temperature, high-pressure lean solution from the generator and the low-temperature rich solution from the absorber. This preheats the rich solution entering the generator to reduce the heat input to the generator, while simultaneously lowering the temperature of the lean solution entering the absorber to improve its absorption efficiency, thus achieving efficient energy utilization within the system. However, a separate solution heat exchanger increases the unit's footprint.

[0004] During actual unit operation, when the heat source entering the generator is steam condensate instead of a pure liquid phase (containing steam), the flow of the two phases within the heat exchange tubes can easily cause vibration. This vibration can lead to wear between the tube walls and baffles, which in turn can cause leaks, forcing the unit to shut down for maintenance. When the steam condensate is a pure liquid phase, the generator operates relatively smoothly without heat exchange tube vibration issues. Condensate containing steam requires pressurization or cooling to remove the steam. Cooling reduces the condensate's heat, affecting generator operation. Pressurizing condensate containing steam requires additional energy input, and the high-temperature, high-pressure lean liquid exiting the generator needs to be throttled and depressurized by a pressure-reducing valve in subsequent process operations.

[0005] In existing absorption refrigeration systems, most of the waste heat from the generator is either vented or returned to the user's pipeline system, resulting in low utilization of waste heat. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a composite generator and its absorption refrigeration system to solve the issues of space requirements in GAX systems and the unstable operation of existing generators, thereby ensuring the stable operation of the absorption refrigeration system.

[0007] The above objectives can be achieved through the following technical solutions:

[0008] The present invention provides a composite generator, including a generator body, wherein a gas chamber and a liquid chamber are respectively provided at the upper and lower ends of the generator body, the gas chamber is located at the gaseous refrigerant outlet of the generator body, and the liquid chamber is located at the rich liquid inlet of the generator body.

[0009] The rich liquid produced by the external absorber exchanges heat with the high-temperature, high-pressure gaseous refrigerant formed by the thermal decomposition of the generator in the gas chamber, and then enters the shell side of the generator body through the liquid chamber. The heat source that has undergone heat exchange and the high-temperature, high-pressure lean liquid that has undergone thermal decomposition in the generator body enter the liquid chamber respectively to preheat the rich liquid that has passed through the gas chamber.

[0010] As a further improvement to the above technical solution, the gas tank is provided with a gas turbine, a liquid-rich spiral tube and a gas outlet in sequence from top to bottom in the cylindrical section, and the inlet and outlet of the liquid-rich spiral tube are both provided with tube sheets.

[0011] As a further improvement to the above technical solution, the output shaft end of the gas turbine is provided with a power generation module, the inlet of the liquid-rich spiral tube is provided with a magnetic feedback valve, and the magnetic feedback valve is powered by the power generation module.

[0012] As a further improvement to the above technical solution, the magnetically controlled feedback valve includes a first valve body through which the rich liquid flows, a second valve body on the first valve body, a valve stem passing through the first valve body inside the second valve body, and two sets of mutually exclusive electromagnets on the top of the valve stem and the upper part of the second valve body. A spring is provided on the valve stem, and a valve disc for controlling the flow rate of the rich liquid is provided at the lower end of the valve stem located inside the first valve body. The power generation module controls the two sets of mutually exclusive electromagnets.

[0013] As a further improvement to the above technical solution, the outer wall of the liquid-rich spiral tube is uniformly provided with fins perpendicular to the spiral tube wall.

[0014] As a further improvement to the above technical solution, the cylindrical section of the liquid tank is provided with two sets of wound spiral tubes, namely a heat source spiral tube for flowing through the heat source after heat exchange in the generator body and a lean liquid spiral tube for flowing through the high temperature and high pressure lean liquid formed by heat decomposition in the generator body. Both sets of spiral tubes are provided with tube sheets at their inlet and outlet. The shell side of the cylindrical section of the liquid tank is filled with rich liquid, and the bottom end of the cylindrical section of the liquid tank is provided with a rich liquid inlet.

[0015] As a further improvement to the above technical solution, the lean liquid outlet of the generator body is provided with a driving liquid wheel, and the heat source inlet of the generator is provided with a driven liquid wheel, which is driven by the driving liquid wheel.

[0016] This invention provides an absorption refrigeration system, including an absorber, a condenser, an evaporator, a CVX heat exchanger, a solution pump, and a precooler, and also includes the aforementioned composite generator. The rich liquid outlet of the absorber is connected to the rich liquid spiral tube inlet of the gas chamber via the solution pump, and the lean liquid outlet of the generator body is connected to the lean liquid inlet of the absorber via the lean liquid spiral tube of the liquid chamber and the precooler.

[0017] The beneficial effects of this invention are as follows:

[0018] 1. By removing the liquid droplets entrained in the desorbed gaseous refrigerant and recovering some of the heat contained in the desorbed gas, the evaporation efficiency of the evaporator is improved, while the cooling capacity required by the condenser is reduced, thereby improving the operating efficiency of the unit.

[0019] 2. Integrating the GAX and generator into one unit can reduce the number of devices and thus the footprint of the unit.

[0020] 3. Using the high-pressure energy of the high-temperature, high-pressure lean liquor generated by the generator to pressurize the heat source entering the generator can improve the unit's energy utilization rate. At the same time, the depressurized lean liquor can enter the subsequent equipment, which can reduce the pressure-bearing capacity requirements of the equipment and reduce the cost of the equipment.

[0021] 4. The waste heat from the generator is reintroduced into the generator to preheat the rich liquid entering the generator. This improves the utilization rate of waste heat and reduces the heat input to the generator, thereby improving the unit's performance. Attached Figure Description

[0022] Figure 1 This is a structural diagram of an existing generator;

[0023] Figure 2 This is a schematic diagram of an existing absorption refrigeration system.

[0024] Figure 3 This is a structural diagram of the composite generator in this invention;

[0025] Figure 4 This is a schematic diagram of the magnetic feedback valve structure of the present invention;

[0026] Figure 5 This is a flowchart of the magnetic feedback valve control process of the present invention;

[0027] Figure 6 This is a schematic diagram of the connection between the first and second liquid impellers of the present invention;

[0028] Figure 7 This is a schematic diagram of the absorption refrigeration system in this invention.

[0029] Diagram: 1. Generator body; 11. Driving hydraulic impeller; 12. Driven hydraulic impeller; 2. Gas tank; 21. Rich liquid spiral tube; 211. Fins; 22. Gas impeller; 23. Magnetically controlled feedback valve; 231. First valve body; 232. Second valve body; 233. Valve stem; 234. Electromagnet; 235. Spring; 236. Valve disc; 3. Liquid tank; 31. Lean liquid spiral tube; 32. Heat source spiral tube. Detailed Implementation

[0030] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0031] Example 1

[0032] This embodiment provides a composite generator, including a generator body 1, the internal structure of which is similar to... Figure 1 The existing generator structure shown is the same. The upper and lower ends of the generator body 1 are respectively provided with a gas reservoir 2 and a liquid reservoir 3. The gas reservoir 2 is located at the gaseous refrigerant outlet of the generator body 1, and the liquid reservoir 3 is located at the rich liquid inlet of the generator body 1.

[0033] like Figure 3 As shown, a liquid-rich spiral tube 21 (spiral wound tube heat exchanger) is installed inside the gas chamber 2, and a gas turbine 22 is installed at the inlet of the gas chamber 2. A magnetically controlled feedback valve 23 is installed at the inlet of the liquid-rich spiral tube 21, and the magnetically controlled feedback valve 23 is powered by a power generation module. The gas turbine 22 drives the power generation module to control the opening degree of the magnetically controlled feedback valve 23.

[0034] The desorbed gas, carrying liquid droplets, is spirally wound upwards along the spiral tube inside the gas reservoir 2. Under the combined action of gravity and centrifugal force, the liquid droplets separate from the desorbed gas. Because the spiral section of the heat exchange tube is welded with external fins 211, the desorbed gas carrying liquid droplets first impacts the external fins 211, resulting in inertial separation. Therefore, under the triple action of impact inertial force, gravity, and centrifugal force, the liquid droplets in the desorbed gas can be efficiently removed. At the same time, when the desorbed gas impacts the external fins 211 of the spiral tube, it can efficiently exchange heat with the rich liquid inside the tube, preheating the rich liquid.

[0035] The above methods can remove the liquid droplets entrained in the desorbed gas and recover some of the heat contained in the desorbed gas, thereby improving the evaporation efficiency of the evaporator and reducing the cooling capacity required by the condenser, thus improving the operating efficiency of the unit.

[0036] Furthermore, the gas-driven turbine 22 generates electricity, and the opening of the magnetic feedback valve 23 is controlled by the power generation module. For example... Figure 5 As shown, the magnetically controlled feedback valve 23 includes a first valve body 231 through which the rich liquid flows, a second valve body 232 on the first valve body 231, a valve stem 233 passing through the first valve body 231 inside the second valve body 232, and two sets of mutually exclusive electromagnets 234 at the top of the valve stem 233 and the upper end inside the second valve body 232. A spring 235 is provided on the valve stem 233, and a valve disc 236 for controlling the flow rate of the rich liquid is provided at the lower end of the valve stem 233 inside the first valve body 231. The power generation module controls the two sets of mutually exclusive electromagnets 234. Figure 4-5 As shown, when the amount of desorbed gas increases, the power generation increases, the magnetism of electromagnet 234 strengthens, and the attraction between the upper and lower magnets exceeds the preload of spring 235, causing valve stem 233 to rise and the valve opening to increase. Similarly, when the amount of desorbed gas decreases, the valve opening decreases. This allows for timely adjustment of the amount of rich liquid entering the generator based on the amount of desorbed gas. This prevents excessive desorption from the generator, which could lead to crystallization. The self-adjustment is sensitive, rapid, and without hysteresis.

[0037] like Figure 2 As shown, two sets of spiral wound tube heat exchangers are installed inside the liquid tank 3, forming a dual-channel spiral tube heat exchanger. The spiral tubes are heat source spiral tubes 32 and 331, which are used to circulate the heat source after heat exchange in the generator body 1 and heat source spiral tubes 32 and 331, which are used to circulate the high-temperature and high-pressure lean liquid formed by heat decomposition in the generator body 1. Both sets of spiral tubes have tube sheets at their inlet and outlet. The shell side of the liquid tank 3 flows with rich liquid, and the bottom of the liquid tank 3 has a rich liquid inlet.

[0038] The high-temperature, high-pressure lean liquid flowing out of the generator shell side drives the active liquid wheel 11 to rotate, becoming a high-temperature lean liquid. This is then introduced into port A1 of the liquid reservoir 3, entering the tube side of a set of spiral wound tube heat exchangers. After heating the rich liquid in the liquid reservoir 3, it flows out from port A2, becoming a low-temperature, low-pressure lean liquid. For example... Figure 7 As shown, the rotation of the driving liquid impeller 11 drives the rotation of the driven liquid impeller 12, which pressurizes the steam condensate containing steam to make it a pure liquid condensate. The condensate after heat exchange enters port B1 of the liquid reservoir 3, enters the tube side of another set of spiral wound tube heat exchangers, heats the rich liquid in the liquid reservoir 3, and then flows out from port B2.

[0039] In the liquid tank 3 above, one set of spiral wound tube heat exchangers replaces the GAX, integrating the GAX with the generator to reduce one unit and thus decrease the unit's footprint. Another set of spiral wound tube heat exchangers draws the waste heat from the generator back into the generator for heating the rich liquid. This improves the utilization rate of waste heat and reduces the heat input to the generator, thereby enhancing the unit's performance.

[0040] like Figure 6As shown, the generator body 1 has a driving liquid wheel 11 and a driven liquid wheel 12 installed in the lean liquid outlet pipe and the heat source inlet pipe, respectively. The two sets of liquid wheels are connected to sprockets via shafts, and the sprockets are connected to each other via chains. In this way, the driving liquid wheel 11 drives the driven liquid wheel 12 to rotate. However, in actual use, the transmission connection method is not limited to this.

[0041] like Figure 7 As shown, this embodiment provides an absorption refrigeration system including an absorber, a condenser, an evaporator, a CVX heat exchanger, a solution pump, and a precooler. It also includes the aforementioned composite generator. The rich liquid outlet of the absorber is connected to the rich liquid spiral tube 21 inlet of the gas reservoir 2 via the solution pump. The lean liquid outlet of the generator body 1 is connected to the lean liquid inlet of the absorber via the heat source spiral tube 3231 of the liquid reservoir 3 and the precooler. The high-pressure, high-temperature lean liquid flowing out of the generator drives the active liquid wheel 11 to rotate. The rotation of the active liquid wheel 11 drives the driven liquid wheel 12 to pressurize the steam-laden condensate (the heat source entering the generator) into a pure liquid phase condensate. This allows the energy of the high-pressure lean liquid flowing out of the generator to be converted for pressurizing and eliminating steam in the heat source condensate, ensuring stable generator operation and extending the unit's service life. Simultaneously, the depressurized lean liquid enters subsequent equipment, reducing the pressure requirements on the equipment, decreasing equipment costs, and improving the unit's energy utilization rate. Compared to other systems... Figure 2 The existing absorption refrigeration system shown can replace the use of a pressure reducing valve between the absorber and the precooler.

[0042] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various improvements without departing from the concept of the present invention, and these improvements all fall within the scope of protection of the present invention.

Claims

1. A composite generator, characterized in that, The generator body includes a gas reservoir and a liquid reservoir, respectively located at the upper and lower ends of the generator body. The gas reservoir is located at the gaseous refrigerant outlet of the generator body, and the liquid reservoir is located at the rich liquid inlet of the generator body. The rich liquid produced by the external absorber exchanges heat with the high-temperature, high-pressure gaseous refrigerant formed by the thermal decomposition of the generator in the gas chamber, and then enters the shell side of the generator body through the liquid chamber. The heat source that has undergone heat exchange and the high-temperature, high-pressure lean liquid that has undergone thermal decomposition in the generator body enter the liquid chamber respectively to preheat the rich liquid that has passed through the gas chamber.

2. The composite generator according to claim 1, characterized in that, The gas chamber is provided with a gas turbine, a liquid-rich spiral tube and a gas outlet in the cylindrical section from top to bottom. The inlet and outlet of the liquid-rich spiral tube are both provided with tube sheets.

3. The composite generator according to claim 2, characterized in that, The output shaft end of the gas turbine is equipped with a power generation module, and the inlet of the liquid-rich spiral tube is equipped with a magnetic feedback valve, which is powered by the power generation module.

4. The composite generator according to claim 3, characterized in that, The magnetically controlled feedback valve includes a first valve body through which the rich liquid flows, a second valve body on the first valve body, a valve stem passing through the first valve body inside the second valve body, and two sets of mutually exclusive electromagnets at the top of the valve stem and the upper part of the second valve body. A spring is provided on the valve stem, and a valve disc for controlling the flow rate of the rich liquid is provided at the lower end of the valve stem located inside the first valve body. The power generation module controls the two sets of mutually exclusive electromagnets.

5. The composite generator according to claim 2, characterized in that, The outer wall of the liquid-rich spiral tube is uniformly provided with fins perpendicular to the tube wall.

6. The composite generator according to claim 1, characterized in that, The cylindrical section of the liquid tank is provided with two sets of wound spiral tubes, namely a heat source spiral tube for flowing through the heat source after heat exchange in the generator body and a lean liquid spiral tube for flowing through the high temperature and high pressure lean liquid formed by heat decomposition in the generator body. Both sets of spiral tubes are provided with tube sheets at the inlet and outlet. The shell side of the cylindrical section of the liquid tank flows with rich liquid, and the bottom end of the cylindrical section of the liquid tank is provided with a rich liquid inlet.

7. The composite generator according to claim 6, characterized in that, The generator body has a lean liquid outlet equipped with a drive liquid wheel, and the generator heat source inlet is equipped with a driven liquid wheel, which is driven by the drive liquid wheel.

8. An absorption refrigeration system, comprising an absorber, a condenser, an evaporator, a CVX heat exchanger, a solution pump, and a precooler, characterized in that, It also includes a composite generator as described in any one of claims 1-7, wherein the rich liquid outlet of the absorber is connected to the rich liquid spiral tube inlet of the gas chamber via a solution pump, and the lean liquid outlet of the generator body is connected to the lean liquid inlet of the absorber via the lean liquid spiral tube of the liquid chamber and a precooler.

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