Drinking water system for absorbing refrigeration unit heating side constant pressure device and method

Abstract

This invention relates to a device for maintaining pressure on the heating side of an absorption chiller unit within a drinking water system. The drinking water system includes an elevated drinking water tank, a lower drinking water tank, and a drinking water delivery unit. The elevated drinking water tank is connected to both the lower drinking water tank and the heating side of the absorption chiller unit. The elevated drinking water tank receives drinking water prepared by a seawater desalination system and can replenish water to both the lower drinking water tank and the heating side of the absorption chiller unit. This invention changes the conventional practice of drinking water systems serving only domestic users. The drinking water system also functions as a water replenishment and pressure maintenance device for the heating side of the absorption chiller unit, achieving an organic combination of drinking water quality and water pressure in the refrigeration system. On one hand, replacing the refrigeration unit's water replenishment and pressure maintenance device with the drinking water system optimizes system configuration and saves on platform gas consumption, electricity consumption, and space. On the other hand, it increases the flowability of water in both systems, reducing the risk of corrosion and scaling in the refrigeration system.

Description

Technical Field

[0001] This invention relates to the field of water replenishment and pressure stabilization technology for marine absorption refrigeration systems, specifically to a device and method for stabilizing the heating side of an absorption refrigeration unit in a drinking water system. Background Technology

[0002] Offshore gas turbine-driven generator sets generate high-temperature flue gas, resulting in considerable waste heat recovery. The heat obtained through high-temperature waste heat recovery devices can be used for platform heat users. Absorption chillers are one such platform heat user. They primarily use high-temperature heat transfer oil for heat exchange, which then serves as the heat source for a hot-water lithium bromide absorption chiller to further heat the refrigeration cycle fluid, effectively utilizing offshore flue gas waste heat for cooling. To reduce the risk of system corrosion and scaling, the water quality of the heat exchange system on the heating side of the absorption chiller must meet at least softened water standards, with chloride ion, sulfate ion, and calcium carbonate hardness all required to be less than 50 mg / L. Furthermore, due to the low cooling load demand of users, the circulation flow rate on the heating side of the absorption chiller is only one-tenth to one-hundredth of that of conventional platform heat exchange systems, and the system requires intermittent small-volume water replenishment during pressure stabilization. Therefore, this system is characterized by high water quality requirements, low system flow rate and water volume, and infrequent water replenishment.

[0003] Regarding the two aspects mentioned above, existing offshore platforms typically employ two-stage reverse osmosis seawater desalination to produce drinking water, which meets the makeup water requirements of absorption chiller systems. This existing practice stores the desalination effluent in soft water tanks or pressurized water tanks and periodically replenishes the absorption chiller system via a dedicated booster pump. This results in an additional makeup water system and low makeup water flow. Existing technologies address pressure control by using pressure-controlled tanks, makeup water pumps, and pressurized gas to maintain pressure on the pressure-controlled tanks to meet the makeup water and pressure control requirements of the absorption chiller's heat source side. However, this leads to large tanks, significant space requirements, and high power and gas consumption, making it uneconomical and energy-inefficient.

[0004] Therefore, there is an urgent need for a device and method for using a drinking water system to maintain constant pressure on the heating side of an absorption chiller. Summary of the Invention

[0005] One objective of this invention is to provide a device for maintaining constant pressure on the heating side of an absorption chiller in a drinking water system, solving the problems of existing devices that provide makeup water and maintain constant pressure to the heat source side of an absorption chiller, which have large footprints, high energy and gas consumption, and low makeup water flow. Another objective of this invention is to provide a method for maintaining constant pressure on the heating side of an absorption chiller in a drinking water system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first aspect of the present invention provides a device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system, comprising a drinking water system and an absorption chiller unit. The drinking water system includes a high-level drinking water tank, a low-level drinking water tank, and a drinking water delivery unit. The high-level drinking water tank is connected to the low-level drinking water tank and the heating side of the absorption chiller unit, respectively. The high-level drinking water tank is used to receive drinking water prepared by a seawater desalination system, and the high-level drinking water tank can replenish water to the low-level drinking water tank and the heating side of the absorption chiller unit.

[0008] The drinking water system is used as a device for maintaining constant pressure on the heating side of an absorption chiller. Preferably, the low-level drinking water tank is connected to the bottom of the high-level drinking water tank via a water supply pipe from the low-level drinking water tank, the heating side of the absorption chiller is connected to the side wall of the high-level drinking water tank via a water supply pipe from the heating side of the absorption chiller, and the water supply pipe from the heating side of the absorption chiller is located below the lowest water level of the high-level drinking water tank.

[0009] The drinking water system is used as a device for maintaining constant pressure on the heating side of the absorption chiller unit. Preferably, the diameter of the water supply pipe of the elevated drinking water tank is larger than the diameter of the water supply pipe on the heating side of the absorption chiller unit.

[0010] The drinking water system is a device for maintaining constant pressure on the heating side of an absorption chiller. Preferably, the drinking water delivery section includes a drinking water pump and a drinking water pump pressure pipe. The inlet of the drinking water pump pressure pipe is connected to the low-level drinking water tank, and the outlet of the drinking water pump pressure pipe supplies water to drinking water users. The drinking water pump is installed on the drinking water pump pressure pipe.

[0011] The drinking water system described herein is used as a device for maintaining constant pressure on the heating side of an absorption chiller. Preferably, the heating side of the absorption chiller includes a heating side heat exchanger, a heating side circulating water supply pipe, a heating side drain pipe, a heating side circulating return pipe, and a heating side makeup water pipe. The heating side heat exchanger is equipped with the heating side circulating water supply pipe and the heating side circulating return pipe. The heating side circulating water supply pipe is equipped with the heating side drain pipe. The heating side circulating water supply pipe is connected to the elevated drinking water tank via the heating side makeup water pipe.

[0012] The drinking water system is used as a device for maintaining constant pressure on the heating side of the absorption chiller unit. Preferably, the circulating water supply pipe on the heating side of the absorption chiller unit is equipped with a circulating water pump on the heating side of the absorption chiller unit.

[0013] The drinking water system is used as a device for maintaining constant pressure on the heating side of an absorption chiller unit. Preferably, a pressure relief valve is provided on the drain pipe on the heating side of the absorption chiller unit.

[0014] The drinking water system is used as a device for maintaining constant pressure on the heating side of the absorption chiller unit. Preferably, a check valve is provided on the water supply pipe on the heating side of the absorption chiller unit.

[0015] The drinking water system described herein is used as a device for maintaining constant pressure on the heating side of an absorption chiller. Preferably, the elevated drinking water tank is further provided with an elevated drinking water tank supply pipe and an elevated drinking water tank level controller. The elevated drinking water tank supply pipe is installed on the elevated drinking water tank and is used to additionally supply water to the elevated drinking water tank. The elevated drinking water tank level controller is installed on the elevated drinking water tank and is used to detect the water level in the elevated drinking water tank.

[0016] A second aspect of the present invention provides a method for maintaining constant pressure on the heating side of an absorption chiller in a drinking water system, comprising the apparatus for maintaining constant pressure on the heating side of the drinking water system in an absorption chiller, the method comprising the following steps:

[0017] Low-level drinking water tanks provide drinking water to users;

[0018] When the water level in the low-level drinking water tank drops to the lowest water level in the low-level drinking water tank and / or the pressure relief valve on the heating side of the absorption chiller releases expansion water or expansion gas, the high-level drinking water tank simultaneously replenishes water to the low-level drinking water tank and / or the heating side of the absorption chiller.

[0019] When the water level in the elevated drinking water tank reaches the minimum level, open the water supply pipe of the elevated drinking water tank to supply water to the lower drinking water tank and / or the heating side of the absorption chiller unit.

[0020] The present invention has the following advantages due to the adoption of the above technical solutions:

[0021] The elevated drinking water tank replaces the conventional model of pressure expansion tank and water replenishment pump, effectively combining the platform drinking water system with the absorption refrigeration system.

[0022] The "daughter-mother" atmospheric pressure drinking water tank combination device of this invention, installed on an offshore platform, can avoid the mismatch of a small engine pulling a large load in the heating side water replenishment and pressure stabilization system of an absorption refrigeration system. This saves the platform on electricity and gas consumption, and conserves space, making it economical and energy-saving.

[0023] This invention provides a constant pressure water supply for the heating side of an absorption chiller unit while maintaining normal operation of the drinking water system without adding additional equipment. It enhances the flowability of the drinking water system while ensuring the quality of the water supplied to the heating side of the chiller system remains consistently fresh, reducing the amount of chemicals used in the chiller system and lowering the risk of corrosion and scaling.

[0024] This invention changes the conventional practice of using drinking water systems solely for domestic users. This system organically combines a drinking water system with an absorption chiller system, forming a pressure-regulating water supply system for the heat source side of an offshore absorption chiller unit based on a dynamic drinking water circulation mode. This achieves an organic combination of drinking water quality and water pressure with the chiller system, saving the platform's gas consumption, electricity consumption, and space. On the one hand, it optimizes system configuration, eliminating power-consuming equipment and gas-consuming users; on the other hand, it avoids the water quality problem caused by insufficient water supply leading to long-term water quality issues in the pressure tank. This is of great significance for optimizing the operation of the heating-side heat exchange system of offshore absorption chillers. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the present invention.

[0026] The markings in the diagram are as follows:

[0027] 1. Elevated drinking water tank; 11. Elevated drinking water tank water supply pipe; 12. Minimum water level of elevated drinking water tank; 13. Elevated drinking water tank level controller; 14. Elevated valve;

[0028] 2. Low-level drinking water tank; 21. Water supply pipe for low-level drinking water tank; 22. Low-level valve;

[0029] 3. Drinking water pump; 31. Drinking water pump pressure pipe; 32. Drinking water user;

[0030] 4. Heat exchanger on the heating side of the absorption chiller; 41. Circulating water supply pipe on the heating side of the absorption chiller; 42. Drain pipe on the heating side of the absorption chiller; 43. Circulating water return pipe on the heating side of the absorption chiller; 44. Pressure relief valve;

[0031] 5. Circulating water pump on the heating side of the absorption chiller; 51. Water supply pipe on the heating side of the absorption chiller; 52. Check valve. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] This invention provides a device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system. The drinking water system and the absorption chiller unit are included. The drinking water system includes a high-level drinking water tank, a low-level drinking water tank, and a drinking water delivery unit. The high-level drinking water tank is connected to both the low-level drinking water tank and the heating side of the absorption chiller unit. The high-level drinking water tank is used to receive drinking water prepared by a seawater desalination system and can replenish water to both the low-level drinking water tank and the heating side of the absorption chiller unit.

[0034] This invention changes the conventional practice of using drinking water systems solely for residential users. The drinking water system also functions as a heating-side water supply and pressure-regulating device for an absorption chiller, achieving an organic integration of drinking water quality and pressure with the chiller system. On one hand, the drinking water system replaces the chiller unit's water supply and pressure-regulating device, optimizing system configuration and saving on platform gas consumption, electricity, and space. On the other hand, it increases the fluidity of water in both systems, reducing the risk of corrosion and scaling in the chiller system.

[0035] Example 1

[0036] like Figure 1 As shown, a drinking water system is used for supplying water to the heating side of an absorption chiller. The drinking water system and the absorption chiller are described. The drinking water system includes a high-level drinking water tank 1, a low-level drinking water tank 2, and a drinking water conveying unit. The high-level drinking water tank 1 is connected to the low-level drinking water tank 2 and the heating side of the absorption chiller. The high-level drinking water tank 1 is used to receive drinking water prepared by a seawater desalination system and can replenish water to the low-level drinking water tank 2 and the heating side of the absorption chiller.

[0037] Preferably, the elevated drinking water tank 1 and the low-level drinking water tank 2 can be two separate drinking water tanks in a drinking water system in the prior art. Furthermore, the volume of the low-level drinking water tank 2 is smaller than the volume of the elevated drinking water tank 1. Alternatively, the elevated drinking water tank 1 can be an additional tank separately installed in addition to the drinking water tanks in a drinking water system in the prior art.

[0038] The elevated drinking water tank 1 is also equipped with an elevated drinking water tank replenishment pipe 11 and an elevated drinking water tank level controller 13. The elevated drinking water tank replenishment pipe 11 is used to replenish water to the elevated drinking water tank 1. The elevated drinking water tank level controller 13 is installed on the elevated drinking water tank 1. The elevated drinking water tank level controller 13 can detect the water level in the elevated drinking water tank 1. The elevated drinking water tank 1 is equipped with a minimum water level 12. When the water level is reached, the elevated drinking water tank 1 is replenished with water.

[0039] Furthermore, one specific implementation of the high-level drinking water tank level controller 13 is as follows: the high-level drinking water tank level controller 13 includes a level gauge, a level sensor, and a PLC controller. The level gauge is installed on the side wall of the high-level drinking water tank 1, the level sensor is installed on the level gauge, and the PLC controller is installed on the outside of the high-level drinking water tank 1. The level gauge is used to measure the water level in the high-level drinking water tank 1 and transmits the data to the PLC controller through the level sensor. When the water level is lower than the specified minimum water level 12 of the high-level water tank, the PLC controller receives the signal from the level sensor and opens the high-level valve 14 of the high-level drinking water tank replenishment pipe 11 to replenish water to the high-level drinking water tank 1.

[0040] The high-level drinking water tank 1 and the low-level drinking water tank 2 are connected by a water supply pipe 21 from the bottom of the high-level drinking water tank 1 to prevent stagnant water zones in the high-level drinking water tank 1. When the water supply pipe 21 reaches the highest water level in the low-level drinking water tank 2, the low-level valve 22 is closed to stop water supply.

[0041] The low-level drinking water tank 2 is configured as a buffer device to provide drinking water to drinking water users 32. Its volume is smaller than that of the high-level drinking water tank 1. Its function is to form a relay effect in drinking water supply and enhance the water quality renewal of the high-level drinking water tank 1.

[0042] Continue to refer to Figure 1 As shown, the drinking water delivery unit includes a drinking water pump 3 and a drinking water pump pressure pipe 31. The inlet of the drinking water pump pressure pipe 31 is connected to the low-level drinking water tank 2, and the outlet of the drinking water pump pressure pipe 31 supplies water to the drinking water user 32. The drinking water pump 3 is installed on the drinking water pump pressure pipe 31.

[0043] Continue to refer to Figure 1As shown, the heating side of the absorption chiller unit includes a heating side heat exchanger 4, a heating side circulating water supply pipe 41, a heating side drain pipe 42, a heating side circulating return water pipe 43, and a heating side makeup water pipe 51. The heating side heat exchanger 4 is equipped with the heating side circulating water supply pipe 41 and the heating side circulating return water pipe 43. The heating side circulating return water pipe 43 is configured as a circulating return water pipeline for heating the refrigeration working fluid, forming system integrity. The heating side circulating water supply pipe 41 is equipped with the heating side drain pipe 42. The heating side circulating water supply pipe 41 is connected to the elevated drinking water tank 1 through the heating side makeup water pipe 51. The diameters of the circulating water supply pipe and the circulating water return pipe on the heating side of the refrigeration unit are increased by one grade, that is, the calculated ratio of the diameters of the circulating water supply pipe and the circulating water return pipe on the heating side of the refrigeration unit is increased by one grade level, in order to balance and stabilize the very small amount of expansion in the system and reduce the frequency of operation of the pressure relief valve on the heating side of the refrigeration unit.

[0044] The absorption chiller unit is equipped with a pressure relief valve 44 on the drain pipe 42 on the heating side. The pressure relief valve 44 is configured to maintain the system pressure after the system expands and is released.

[0045] The absorption chiller unit is equipped with a check valve 52 on the water supply pipe 51 on the heating side. The check valve 52 is used to prevent the expansion water of the chiller unit from flowing back and to avoid contaminating the high-level drinking water tank 1.

[0046] The heat exchanger 4 on the heating side of the absorption chiller is configured to acquire heat from the high-temperature heat medium of the platform and exchange heat with the drinking water. The heated drinking water exchanges heat with the heating working fluid of the chiller through the circulating water supply pipe 41 on the heating side of the absorption chiller and the circulating water return pipe 43 on the heating side of the absorption chiller.

[0047] Among them, the circulating water supply pipe 41 on the heating side of the absorption chiller is configured as a circulating water supply pipe for heating the working fluid of the refrigeration cycle.

[0048] The absorption chiller heating side circulating water supply pipe 41 is equipped with an absorption chiller heating side circulating water pump 5, which is configured as a power source for hot water circulation on the heating side of the chiller.

[0049] The absorption chiller heating side drain pipe 42 is configured to connect to the beginning of the absorption chiller heating side circulating water supply pipe 41, and is used to discharge a small amount of expansion gas and water.

[0050] The water supply pipe 51 on the heating side of the absorption chiller is configured to connect the high-level drinking water tank 1 and the inlet of the circulating water pump 5 on the heating side of the absorption chiller, and is used for water supply and pressure stabilization of the circulating system on the heating side of the absorption chiller.

[0051] The diameter of the water supply pipe of the high-level drinking water tank 1 is larger than the diameter of the water supply pipe 51 on the heating side of the absorption chiller unit, so that the drinking water supply capacity is greater than the water supply capacity of the chiller unit heating side system.

[0052] The water supply pipe 51 on the heating side of the absorption chiller is connected to the side wall of the elevated drinking water tank 1, and the water supply pipe 51 on the heating side of the absorption chiller is located below the lowest water level 12 of the elevated water tank.

[0053] Example 2

[0054] A method for supplying water to the heating side of an absorption chiller using a drinking water system, based on the drinking water system of Embodiment 1 used in the constant pressure device of the heating side of the absorption chiller, the method includes the following steps:

[0055] S1: Low-level drinking water tank provides drinking water to users;

[0056] S2: When the water level in the low-level drinking water tank drops to the lowest level of the low-level drinking water tank and / or the pressure relief valve on the heating side of the absorption chiller releases expansion water or expansion gas, the high-level drinking water tank simultaneously replenishes water to the low-level drinking water tank and / or the heating side system of the absorption chiller.

[0057] The implementation process of step S2 specifically includes the following two situations:

[0058] S21: The heating side system of the chiller unit is operating stably, and no water replenishment is required. The drinking water system is operating, and the operation of the drinking water system and the absorption chiller unit does not overlap.

[0059] S211: If a drinking water user uses a small amount of water, the drinking water will be supplied by the low-level drinking water tank 2, and the drinking water system and the absorption chiller unit will not be linked.

[0060] S212: If drinking water users use a large amount of water continuously, the water level in the low-level drinking water tank 2 will drop continuously. When the water level drops to the lowest level of the low-level drinking water tank 2, the low-level valve 22 on the water supply pipe 21 of the low-level drinking water tank will be opened, and water will be supplied from the high-level drinking water tank 1 to the low-level drinking water tank 2.

[0061] S22: The heating system of the absorption chiller is experiencing fluctuations in operation, requiring intermittent water replenishment. The drinking water system is also in operation, resulting in overlapping operations between the drinking water system and the absorption chiller.

[0062] S221: If the drinking water user uses a small amount of water, the drinking water system operates in the same way as in step S211. The pressure relief valve 42 on the heating side of the absorption chiller releases a small amount of expanded water or a trace of expanded gas. The elevated drinking water tank 1 replenishes water to the circulating water supply pipe 41 on the heating side of the absorption chiller.

[0063] S222: If drinking water users have a continuous large amount of water usage, the operation of the drinking water system is the same as in step S212, and the operation of the heating side system of the absorption chiller is the same as in step S221.

[0064] Steps S21 and S22 also include step S23: when the water level of the high-level drinking water tank 1 reaches the lowest water level 12 of the high-level drinking water tank, the water supply pipe 11 of the high-level drinking water tank is opened to supply water to the drinking water system and the absorption chiller unit.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for maintaining constant pressure on the heating side of an absorption chiller unit using a drinking water system, comprising a drinking water system and an absorption chiller unit, characterized in that, The drinking water system includes an elevated drinking water tank, a low-level drinking water tank, and a drinking water delivery unit. The elevated drinking water tank is connected to the low-level drinking water tank and the heating side of the absorption chiller unit. The elevated drinking water tank is used to receive drinking water prepared by the seawater desalination system and can replenish water to the low-level drinking water tank and the heating side of the absorption chiller unit. The low-level drinking water tank is connected to the bottom of the high-level drinking water tank through the water supply pipe of the low-level drinking water tank. The heating side of the absorption chiller is connected to the side wall of the high-level drinking water tank through the water supply pipe of the heating side of the absorption chiller. The water supply pipe of the heating side of the absorption chiller is located below the lowest water level of the high-level drinking water tank. The diameter of the water supply pipe for the elevated drinking water tank is larger than the diameter of the water supply pipe on the heating side of the absorption chiller unit.

2. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 1, characterized in that, The drinking water delivery unit includes a drinking water pump and a drinking water pump pressure pipe. The inlet of the drinking water pump pressure pipe is connected to the low-level drinking water tank, and the outlet of the drinking water pump pressure pipe supplies water to drinking water users. The drinking water pump is installed on the drinking water pump pressure pipe.

3. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 2, characterized in that, The heating side of the absorption chiller unit includes a heating side heat exchanger, a heating side circulating water supply pipe, a heating side drain pipe, a heating side circulating return pipe, and a heating side makeup water pipe. The heating side heat exchanger is equipped with the heating side circulating water supply pipe and the heating side circulating return pipe. The heating side circulating water supply pipe is equipped with the heating side drain pipe. The heating side circulating water supply pipe is connected to the elevated drinking water tank through the heating side makeup water pipe.

4. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 3, characterized in that, The absorption chiller is equipped with a circulating water pump on the heating side of the circulating water supply pipe.

5. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 4, characterized in that, The absorption chiller unit is equipped with a pressure relief valve on the drain pipe on the heating side.

6. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 5, characterized in that, The absorption chiller unit is equipped with a check valve on the water supply pipe on the heating side.

7. The device for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system according to claim 6, characterized in that, The elevated drinking water tank is also equipped with an elevated drinking water tank replenishment pipe and an elevated drinking water tank level controller. The elevated drinking water tank replenishment pipe is installed on the elevated drinking water tank and is used to replenish the elevated drinking water tank with additional water. The elevated drinking water tank level controller is installed on the elevated drinking water tank and is used to detect the water level height of the elevated drinking water tank.

8. A method for maintaining constant pressure on the heating side of an absorption chiller unit using a drinking water system, characterized in that, The method, based on the apparatus for maintaining constant pressure on the heating side of an absorption chiller unit in a drinking water system as described in any one of claims 1 to 7, comprises the following steps: Low-level drinking water tanks provide drinking water to users; When the water level in the low-level drinking water tank drops to the lowest water level in the low-level drinking water tank and / or the pressure relief valve on the heating side of the absorption chiller releases expansion water or expansion gas, the high-level drinking water tank simultaneously replenishes water to the low-level drinking water tank and / or the heating side of the absorption chiller. When the water level in the elevated drinking water tank reaches the minimum level, open the water supply pipe of the elevated drinking water tank to supply water to the lower drinking water tank and / or the heating side of the absorption chiller unit.

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