A hot water ring line system combined with waste heat resource heat recovery of regional multiple air compression stations

Abstract

The present application relates to a kind of hot water ring line systems of combined regional multi-space compression station waste heat resource heat recovery, including supply side module, hot water ring line, demand side module;Supply side module includes heat exchange type connection's air compressor cooling water circuit, first water tank water storage-water supply flow path, backwater flow path;Hot water ring line is connected with the water tank water storage-water supply flow path;Backwater flow path is used for the backwater of hot water ring line to first water tank water storage-water supply flow path;Demand side module includes mutually connected second water tank water storage-water supply flow path and user end, and the second water tank water storage-water supply flow path is connected with the hot water ring line.Compared with prior art, the present application is convenient for centralized recovery including but not limited to the low-grade, discontinuous heat energy of air compression station to prepare domestic hot water.By water source heat pump, centralized waste heat resource is recycled and utilized, and hot water is prepared, compared with the centralized waste heat resource directly through heat exchanger to heat water, with higher energy efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air compression station waste heat resource recovery, in particular to a hot water ring line system combining regional multi-air compression station waste heat resource heat recovery. BACKGROUND

[0002] Various industries will face new challenges and opportunities, and how to solve the contradiction between economic development and environmental protection has been a hot issue. Industry accounts for a large part of energy consumption in China, so promoting industrial energy saving through technological innovation and other methods can greatly reduce energy consumption. Industrial energy saving can reduce production costs while having a positive effect on environmental protection and resource utilization.

[0003] Among the various ways to promote industrial energy saving, waste heat resource recycling is an effective way. Air compression stations, as major energy consumers in industrial parks, account for more than 10% of total power consumption, with total annual power consumption reaching 300 billion degrees. Some parks have multiple air compression stations. A large amount of waste heat is generated during the operation of air compression stations, which is a valuable distributed concentrated waste heat resource. Air compression station waste heat recovery converts waste heat into other forms of energy for heating, producing hot water, etc., improving energy utilization efficiency while reducing dependence on traditional energy sources. By reducing the use of coal or other fossil fuels, carbon footprint is reduced.

[0004] The traditional air compression station cooling method is to use a cooling water pump to drive cooling water to absorb waste heat, then enter a cooling tower to dissipate heat and return to the air compression station. The heat is dissipated to the environment, resulting in a large amount of waste heat resources being wasted. To solve this problem, the commonly used recycling method is to use steam or condensate water as high-temperature waste heat resource to directly exchange heat through a heat exchanger to produce hot water for daily use. Due to the limitations of heat extraction technology, this direct heat exchange method often has low efficiency, and a large amount of low-temperature, limited-grade waste heat resources are difficult to be reasonably applied. With the development of heat pump technology, water source heat pump has gradually appeared to absorb waste heat to produce hot water for daily use. Waste heat recovery resources often come from industrial parks, and the corresponding hot water system often uses a centralized heating system to deliver hot water to different areas. The system is equipped with a large heat storage tank, and the water is heated by the heat pump system and sent to the heat storage tank to form a central hot water supply station. The hot water is delivered to each water user through hot water pipes. However, the heat storage tank has problems such as water mixing loss and excess water directly discharged and wasted. At the same time, the current waste heat recovery technology often uses a point-to-point recycling method, which provides some demand points in close proximity after recycling the concentrated waste heat resources, ignoring the possibility of comprehensive allocation of distributed waste heat resources in the region, reducing the supply range of waste heat resource recycling. With the continuous development of intelligent control, it is possible to combine appropriate control methods to centrally allocate regional waste heat resources, further expanding the utilization rate and use range.

[0005] The existing industrial park waste heat recovery heating hot water system has the following problems: first, most industrial parks directly heat hot water through a heat exchanger using waste heat resources, and the utilization efficiency of this method is low. For example, a kind of air compressor waste heat recycling system disclosed in patent CN 112145429A increases the contact time of water and heat by changing the structure of the heat exchanger to increase the waste heat disturbance and water flow, thereby improving the conversion efficiency. However, this method does not consider the heat loss during long-distance transmission of hot water, and the heat exchange capacity is lower than that of a heat pump system. Second, some industrial parks use heat pump technology to increase energy efficiency, but do not consider the problem of intermittent supply of waste heat resources. For example, a kind of air compression station waste heat recovery system based on a water source heat pump unit disclosed in patent CN 110762898A absorbs waste heat through a water source heat pump to produce hot water, but does not consider the problem of intermittent heating supply when the air compressor unit is shut down and the heat pump lacks cooling water as a heat source. Third, due to the instability of waste heat resources, some systems are equipped with water tanks to store hot water, but the water tank is only used for peak shaving storage and does not tap its other potential, such as water recycling. When there is a surplus of water in the tank, it is often directly discharged, causing waste. For example, a kind of double-source double-tank heat pump water supply system proposed in patent CN 211204209 U increases the hot water storage tank to ensure stable heating when the main heat source is insufficient, but there is a problem of water mixing loss and the system does not consider water recycling. Fourth, after the regional distributed centralized waste heat resource recovery, it is often only provided to the nearby user end, and the role of waste heat resource allocation in the region is ignored, which reduces the hot water supply range and the utilization potential is not fully tapped. SUMMARY

[0006] The purpose of the present application is to overcome the defects of the prior art and provide a hot water ring line system combining regional multi-air compression station waste heat resource heat recovery. The system uses a water source heat pump to produce hot water using centralized waste heat resources from air compression stations, considers the existence of distributed air compression stations in the region, adopts a hot water ring line mode, increases the hot water supply range, and has the functions of water recycling and water reheating, thereby reducing water waste, considering the problem of transmission distance loss and intermittent supply of waste heat resources, and providing a water tank and an air source heat pump unit at the user end to realize hot water storage and full-time heating functions. Through the coordination of multiple operating modes, the system has the lowest comprehensive energy consumption and the highest energy saving rate.

[0007] The purpose of the present application can be achieved by the following technical solutions:

[0008] The present application provides a hot water ring line system combining regional multi-air compression station waste heat resource heat recovery, which comprises a supply side module, a hot water ring line, and a demand side module.

[0009] The supply side module comprises a heat exchange connected air compressor cooling water circuit, a first water tank water storage and supply flow path, and a return water flow path;

[0010] The hot water ring line is connected with the water tank water storage and supply flow path;

[0011] The return water flow path is used for return water of the hot water ring line to the first water tank water storage and supply flow path;

[0012] The demand side module comprises a second water tank water storage and supply flow path and a user end connected with each other, and the second water tank water storage and supply flow path is connected with the hot water ring line;

[0013] A plurality of supply side modules are arranged along the hot water ring line, and a plurality of demand side modules are arranged along the hot water ring line. The hot water ring line simultaneously connects the supply side modules formed by a plurality of air compressors centralized waste heat resources, receives hot water provided by each supply side module, and makes water in the ring line flow circularly through a circulating water pump on the hot water ring line. Meanwhile, the water in the hot water ring line can also be driven by a ring line recovery pump to return to a water source heat pump unit through a ring line recovery valve for reheating. The hot water ring line simultaneously connects a plurality of demand side modules, and provides hot water in the ring line to the demand side modules according to demand. The hot water ring line can simultaneously connect a plurality of demand side modules to form a ring-shaped water supply structure, thereby increasing the utilization rate of waste heat resources and the heating range.

[0014] Further, the air compressor cooling water circuit comprises an air compressor, a cooling water pump, a variable frequency pump, a first heat exchange channel of a plate heat exchanger, and a cooling tower connected in sequence.

[0015] The air compressor cooling water circuit further comprises a first heat exchange channel of a water source heat pump unit, one end of the first heat exchange channel of the water source heat pump unit is connected with the cooling water pump, and the other end is connected with the cooling tower.

[0016] Further, the first water tank water storage and supply flow path comprises a cold water pump, a second heat exchange channel of a plate heat exchanger, a water supplement valve, a total water tank, a water delivery valve, and a water delivery pump connected in sequence, and the water delivery pump is connected with the hot water ring line.

[0017] The first water tank water storage and supply flow path further comprises a return water valve, a return water pump, and a second heat exchange channel of a water source heat pump unit connected in sequence, the return water valve is connected with the total water tank, and the second heat exchange channel of the water source heat pump unit is connected with the total water tank.

[0018] The return water flow path comprises a ring line recovery valve and a ring line recovery pump connected in sequence, the ring line recovery valve is connected with the hot water ring line, and the ring line recovery pump is connected with the water source heat pump unit.

[0019] The total water tank comprises a total water tank temperature sensor and a total water tank liquid level sensor.

[0020] Further, in specific operation, the cooling water pump drives the cooling water which absorbs the heat of the air compressor, through the action of the frequency conversion pump, part of the cooling water enters the plate heat exchanger and exchanges heat with the cooling water driven by the cooling water pump, the preheated cooling water enters the total water tank through the water supply valve, the cooling water passes through the plate heat exchanger and returns to the cooling tower, and then returns to the air compressor;

[0021] Another part of the cooling water enters the water source heat pump unit, the cooling water is cooled in the unit and then returns to the air compressor, the preheated water in the total water tank is driven by the return water pump, passes through the return water valve, enters the water source heat pump unit, is heated again to a specified temperature, and is sent back to the total water tank, and the water in the total water tank is sent to the hot water ring line through the water supply valve driven by the water supply pump.

[0022] Further, the second water tank storage-water supply flow path comprises, in sequence, an end water supply pump, a reheating valve, an air source heat pump unit, an end water tank, a water supply pump, and a water supply valve, the water supply pump is connected with the hot water ring line, and the water supply valve is connected with the user end;

[0023] The second water tank storage-water supply flow path further comprises a direct sending valve, one end of the direct sending valve is connected with the end water supply pump, and the other end of the direct sending valve is connected with the end water tank;

[0024] The second water tank storage-water supply flow path further comprises an end return water valve, one end of the end return water valve is connected with the water supply pump, and the other end of the end return water valve is connected with the hot water ring line;

[0025] The end water tank is provided with an end water tank temperature sensor and an end water tank liquid level sensor;

[0026] The inlet end of the water supply pump is provided with a water supply temperature sensor.

[0027] The end water tank is provided with an end water tank temperature sensor and an end water tank liquid level sensor, when the delivered hot water reaches a set liquid level, the water supply pump is closed, and when the water temperature is lower than a hot water set temperature, the end return water valve is opened, and the water returns to the hot water ring line through the return water valve driven by the water supply pump.

[0028] Preferably, the end water tank comprises an end water tank temperature sensor and an end water tank liquid level sensor, the water temperature and the liquid level in the water tank can be monitored, and the size and the number of the end water tank can be adjusted according to actual conditions.

[0029] Preferably, the air compressor waste heat resource can also use other centralized waste heat resources meeting the requirements according to actual conditions.

[0030] Preferably, the total water tank contains a total water tank temperature sensor and a total water tank liquid level sensor, the water temperature and liquid level in the water tank can be monitored, and the size and number of the total water tank can be adjusted according to actual conditions.

[0031] Preferably, the water source heat pump module can select different specifications of units and adopt multiple units in series and parallel connection according to actual needs.

[0032] Preferably, the air source heat pump module can select different specifications of units and adopt multiple units in series and parallel connection according to actual needs.

[0033] The hot water ring line system combined with regional multi-air compression station waste heat resource heat recovery is suitable for the recycling and utilization of distributed waste heat resources (including but not limited to air compression station waste heat) in the region. The function of obtaining domestic hot water by waste heat resources is realized through the water source heat pump, the hot water ring line is increased, the hot water obtained by each waste heat resource is connected with each other, the hot water supply range is increased, the utilization rate of waste heat resources is improved, the hot water ring line is also a way to store hot water resources, and air source heat pump units are additionally arranged on the demand side to realize the reheating function and the effective heating function in the whole period. Combined with the water tank, the peak-shaving storage is realized, through the arrangement of valves and pipelines, the waste water can return to the hot water ring line again, the water in the hot water ring line can also return to the water source heat pump unit for reheating, water resource waste is reduced, and combined with multiple operation modes, the system has the lowest comprehensive energy consumption and the highest cost saving rate.

[0034] The hot water ring line of the hot water ring line system combined with regional multi-air compression station waste heat resource heat recovery is a large artery, the supply side module is a heart, the demand side module is an organ, and each part is coordinated to form multiple operation modes to realize various functions.

[0035] Based on the supply side and the hot water ring line, it can be divided into heat storage mode, supply mode, mixed mode, shutdown mode, and ring line backwater reheating mode.

[0036] Heat storage mode: the cooling water in the supply side module driven by the cooling water pump absorbs the heat of the air compression station, and after the adjustment of the frequency conversion pump, part of the cooling water enters the plate heat exchanger to preheat the cold water driven by the cold water pump into the plate heat exchanger. The preheated water enters the total water tank through the water supplement valve, and the cooled cooling water returns to the air compression station through the cooling tower. The other part of the cooling water enters the water source heat pump unit, and after being cooled in the evaporator of the water source heat pump unit, it returns to the cooling tower, and finally returns to the air compression station. The water in the total water tank is driven by the return water pump, enters the water source heat pump unit through the return water valve, and is further heated to return to the total water tank. The target water level and water temperature of the total water tank can be set according to actual needs. When the water temperature detected by the total water tank temperature sensor meets the water supply and heat preservation requirement setting value, and the liquid level in the water tank detected by the total water tank liquid level sensor reaches the setting value, the cold water pump is closed, the water supplement valve is closed, the return water pump is closed, the return water valve is closed, and the water source heat pump unit is stopped.

[0037] Supply mode: when the water tank liquid level sensor in the supply side module detects that there is water source in the water tank, the water temperature detected by the total water tank temperature sensor meets the water supply requirement setting value, the demand side module has hot water demand, or the hot water ring line needs to be supplemented, the water supply valve is opened, the hot water in the total water tank is driven by the water supply pump to enter the hot water ring line, and the target water level and water temperature of the total water tank can be set according to actual needs. When the total water tank liquid level sensor detects that the liquid level in the total water tank decreases to below the set minimum liquid level, the water supply valve and the water supply pump are closed, the supply side switches back to the heat storage mode, the water temperature detected by the total water tank temperature sensor meets the water supply and heat preservation requirement setting value, and the total water tank liquid level sensor detects that the liquid level in the water tank reaches the set value, and then switches to the supply mode until the requirement is met. The hot water prepared by recycling the waste heat is sent into the hot water ring line, and the circulation of the hot water in the ring line is realized by the circulation pump. Due to the large specific heat capacity of water, appropriate heat preservation measures are taken for the pipeline, even if part of the heat is lost during the flow process, but due to the newly supplemented hot water at each point, the temperature of the mixed water is increased, and the stability of the water temperature in the ring line is improved.

[0038] Mixed mode: The cooling water pump in the supply side module absorbs the waste heat of the air compression station. After the adjustment of the frequency conversion pump, part of it enters the plate heat exchanger to preheat the cold water pump driven into the plate heat exchanger. The preheated water enters the total water tank through the water supplement valve. Open the water supply valve and return valve. Part of the water is directly sent to the hot water ring line through the water supply pump. Another part enters the water source heat pump unit through the return water pump and is reheated before returning to the total water tank. At this time, the mixed water temperature in the total water tank rises, and the above process is repeated. Part of it is sent to the water source heat pump unit for reheating, and the other part is directly sent to the hot water ring line. When the demand is met, the system switches to the heat storage or shutdown mode. The hot water produced by recycling the waste heat of each air compression station is sent to the hot water ring line, and the circulation of hot water in the ring line is realized by the circulation pump. Due to the large specific heat capacity of water, appropriate insulation measures are taken for the pipeline, and even if there is some heat loss during the flow process, the temperature of the mixed water can still be raised due to the new hot water added at each point, thereby improving the stability of the water temperature in the ring line.

[0039] Shutdown mode: When the air compression station is shut down or has no waste heat, or when the waste heat resource generation time is peak electricity or peak electricity time, the water source heat pump unit may not work to achieve better comprehensive energy saving and cost saving effect. At this time, the water source heat pump unit is shut down. If there is a water demand on the user side or the hot water ring line needs to be replenished in the shutdown mode, the water supply valve and the water supply pump are opened. When the total water tank level sensor senses that there is water stored in the total water tank, the water in the total water tank is driven by the water supply pump and sent to the hot water ring line through the water supply valve. When the total water tank level sensor senses that the liquid level in the total water tank is lowered, the cold water pump and the water supplement valve are opened. The water driven by the cold water pump enters the total water tank through the water supplement valve and is then sent to the hot water ring line. Since the hot water produced by recycling the waste heat of each air compression station is sent to the hot water ring line, the circulation of hot water in the ring line is realized by the circulation pump. Due to the large specific heat capacity of water, appropriate insulation measures are taken for the pipeline, and the temperature of the mixed water can also be raised by the added water, thereby improving the stability of the water temperature in the ring line.

[0040] Ring line return water reheating mode: This mode corresponds to the situation where the supply side waste heat resource exists but the ring line water temperature is low. The ring line recovery pump of part of the supply side module is started, and the ring line recovery valve is opened. The water in the hot water ring line is driven by the ring line recovery pump and returns to the water source heat pump unit through the ring line recovery valve for reheating, and then enters the total water tank. When the temperature sensor and the liquid level sensor of the total water tank sense that the water temperature and the liquid level meet the requirements, the water supply pump and the water supply valve are opened, and the hot water is delivered to the hot water ring line. This mode can be operated synchronously with the supply mode to reduce water resource waste through ring line water recovery and reheating.

[0041] Based on the demand side and the hot water ring line, it can be divided into direct water supply mode, reheated water mode, and waste water recovery mode.

[0042] Direct water supply mode: the user end sets the target water level and temperature of the terminal water tank according to the load demand, the water supply temperature sensor of the demand side module detects that the hot water temperature in the hot water ring line meets the demand, the terminal water pump is started, the reheat water valve is closed, the air source heat pump unit is stopped, the direct water supply valve is opened, the hot water in the ring line flows into the terminal water tank through the direct water supply valve driven by the terminal water pump, and when the terminal temperature sensor and the terminal liquid level sensor of the terminal water tank detect that the water temperature and liquid level in the terminal water tank meet the demand, the direct water supply valve and the terminal water pump are closed, when the user end uses water, the water supply valve is opened, the water supply pump is started, the terminal backwater valve is closed, and the water supply pump drives the hot water in the terminal water tank to pass through the water supply valve and be sent to the user end. This mode can store hot water through the water tank while transporting hot water, thereby improving the utilization rate of hot water in the hot water ring line.

[0043] Reheating water mode: the user end sets the target water level and temperature of the terminal water tank according to the load demand, the water supply temperature sensor of the demand side module detects that the hot water temperature in the hot water ring line does not meet the demand, but the user end needs hot water or the water tank needs to store hot water in advance, the terminal water pump is started, the reheat water valve is opened, the air source heat pump unit is started, the direct water supply valve is closed, the hot water in the ring line flows into the air source heat pump unit through the reheat water valve driven by the terminal water pump, is further heated by the air source heat pump unit, and then enters the terminal water tank, and when the terminal temperature sensor and the terminal liquid level sensor of the terminal water tank detect that the water temperature and liquid level in the terminal water tank meet the demand, the reheat water valve and the water pump are closed, when the user end uses water, the water supply valve is opened, the water supply pump is started, the water supply pump drives the hot water in the terminal water tank to pass through the water supply valve and be sent to the user end. In the reheating mode, the water in the hot water ring line is higher in temperature than normal cold water, and thus the energy consumption of the air source heat pump unit can be reduced.

[0044] Excess water recovery mode: when the water tank liquid level sensor of the demand side module senses that there is excess water in the terminal water tank, but the water tank temperature sensor senses that the water in the terminal water tank does not meet the demand temperature, the water supply pump is started, the terminal backwater valve is opened, the water supply valve is closed, and the water supply pump drives the excess water in the terminal water tank to return to the hot water ring line through the terminal backwater valve. At this time, the excess water is less in amount and higher in temperature than the water in the ring line, and thus can directly meet the temperature demand of water supply, or can be reheated by starting the air source heat pump reheating water mode or the ring line backwater reheating mode, the excess water recovery mode reduces water resource waste and reduces hot water energy consumption through reasonable pipeline arrangement and control mode.

[0045] Preferably, the various operation modes of the supply side module and the demand side module can be combined in pairs to form multiple combined modes, so as to meet the demand side water demand while achieving the lowest comprehensive energy consumption and the highest cost saving rate.

[0046] Compared with the prior art, the present application has the following beneficial effects:

[0047] 1. The present application is convenient for centralized recovery of low-grade, discontinuous heat energy including but not limited to air compression station to produce domestic hot water. Compared with directly heating water through a heat exchanger, the present application has higher energy efficiency by recovering and utilizing centralized waste heat resources through a water source heat pump to produce hot water.

[0048] 2. The present application uses a hot water ring line to greatly improve the heating range and waste heat resource utilization rate. Based on the waste heat recovery of the centralized waste heat resources by the water source heat pump, the present application proposes a method of connecting multiple supply ends and multiple demand ends in series through a hot water ring line, so that the hot water supply range is greatly improved, and the waste heat resource utilization rate is improved.

[0049] 3. The hot water ring line proposed by the present application can store hot water. By mixing hot water from multiple supply sides with the hot water in the ring line, the temperature reduction rate of the hot water in the ring line is further reduced, and the hot water ring line becomes a large energy storage device.

[0050] 4. The present application uses a combined heat pump, and an air source heat pump unit is additionally arranged near the user end on the basis of the water source heat pump to supplement heating on site. After the air source heat pump is added to the user end, the water source heat pump at the waste heat recovery point can produce and supply hot water below the target temperature, and the heat loss in the storage and transportation process can be reduced by storing and transporting hot water at a lower temperature to the secondary water tank. In addition, the air source heat pump can make up for the problem of insufficient heating caused by intermittent supply of waste heat resources, and realize safe heating at all times.

[0051] 5. The present application can further utilize low-grade waste heat resources by preheating cold water by diverting a part of the cooling water absorbing waste heat into a plate heat exchanger to improve the initial water temperature of cold water heating.

[0052] 6. The present application realizes the functions of peak-shaving storage and waste water recycling by arranging water tanks at the supply side and the demand side. The waste water is transported back to the hot water ring line through the end return water valve, the ring line recovery valve, and the ring line water return water source heat pump reheating, so as to avoid waste of water resources. At the same time, the water temperature is increased after the return water is mixed with the hot water in the ring line, which in turn reduces the energy consumption of the whole system.

[0053] 7. The present application can make full use of valley electricity and avoid peak electricity, which helps to reduce power peak shaving. After the air source heat pump is added, on the one hand, the air source heat pump is more flexible in operation and can selectively operate according to the power structure; on the other hand, the heating pressure of the water source heat pump is reduced, and the necessary operation of the water source heat pump for waste heat recovery is reduced, so that the water source heat pump for waste heat recovery can avoid peak electricity and peak electricity as much as possible. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 It is a principle schematic diagram of hot water ring line system combined with waste heat resource heat recovery of multiple air compression stations in a region.

[0055] Figure 1 In the embodiment, 1, air compressor, 2, cooling tower, 3, cooling water pump, 4, cold water pump, 5, frequency conversion pump, 6, plate heat exchanger, 7, water source heat pump unit, 8, water supplement valve, 9, total water tank temperature sensor, 10, total water tank liquid level sensor, 11, total water tank, 12, return water valve, 13, return water pump, 14, water delivery valve, 15, water delivery pump, 16, ring line recovery pump, 17, ring line recovery valve, 18, hot water ring line, 19, water supplement temperature sensor, 20, terminal water delivery pump, 21, reheat water valve, 22, direct water supply valve, 23, air source heat pump unit, 24, terminal water tank temperature sensor, 25, terminal water tank liquid level sensor, 26, terminal water tank, 27, water supply pump, 28, terminal return water valve, 29, water supply valve, 30, user end, 31, circulating water pump. DETAILED DESCRIPTION

[0056] The present application will be described in detail below in combination with the drawings and specific embodiments. In the technical solution, if the component model, material name, connection structure, control method, algorithm and other features are not explicitly described, they are regarded as common technical features disclosed in the prior art.

[0057] The present application will be described in detail below in combination with the drawings and specific embodiments.

[0058] In the embodiment, it is a hot water ring line system combined with waste heat resource heat recovery of multiple air compression stations in a region, as shown in the figure, composed of a supply side module, a hot water ring line and a demand side module. Figure 1

[0059] Among them, the supply side module has an air compressor 1, a cooling tower 2, a cooling water pump 3, a cold water pump 4, a frequency conversion pump 5, a plate heat exchanger 6, a water source heat pump unit 7, a total water tank 11, a return water pump 13, a water supplement valve 8, a return water valve 12, a water delivery valve 14, a water delivery pump 15, a ring line recovery pump 16 and a ring line recovery valve 17.

[0060] ​Specific operation, cooling water pump 3 driven by the absorption of air compressor 1 heat of cooling water, through the action of variable frequency pump 5, a part of the cooling water into the plate heat exchanger 6 and cold water pump 4 driven by cold water heat exchange, preheated cold water through the water valve 8 into the total water tank 11, cooling water after the plate heat exchanger 6 back to the cooling tower 2, back to the air compressor 1. Another part of the cooling water into the water source heat pump unit 7, cooling water in the unit is cooled back to the air compressor 1, the total water tank 11 in the preheated water through the backwater pump 13 driven by the backwater valve 12, into the water source heat pump unit 7, is heated again to the specified temperature, send back to the total water tank 11, the total water tank 11 in the water through the water pump 15 driven by the water valve 14 to the hot water ring line 18.

[0061] The total water tank 11 contains total water tank temperature sensor 9 and total water tank liquid level sensor 10, which can monitor the water temperature and liquid level in the tank, the size and number of total water tank 11 can also be adjusted according to actual situation.

[0062] The hot water ring line 18 is connected to multiple concentrated waste heat resource supply side modules, receives hot water provided by each supply side module, and circulates water in the ring line through the circulating water pump 31 on the hot water ring line 18. At the same time, the water in the hot water ring line 18 can also be heated by the ring line recovery pump 16 through the ring line recovery valve 17 back to the water source heat pump unit 7. The hot water ring line 18 is also connected to multiple demand side modules, which provide hot water in the ring line to the demand side modules according to demand.

[0063] The demand side module includes a water supply temperature sensor 19, an end water pump 20, a direct delivery valve 22, a reheating valve 21, an air source heat pump unit 23, an end water tank 26, a water supply valve 29, a water supply pump 27, an end return valve 28, and a user end 30.

[0064] Specific operation, according to the different water temperature sensed by the water supply temperature sensor 19, the hot water driven by the end water pump 20 can be sent to the end water tank 26 through the direct delivery valve 22, or can enter the air source heat pump unit 23 through the reheating valve 21. The water is heated again and sent to the end water tank 26. The hot water in the end water tank 26 is driven by the water supply pump 27 through the water supply valve 29 and sent to the user end 30.

[0065] The end water tank 26 is provided with an end water tank temperature sensor 24 and an end water tank liquid level sensor 25. When the delivered hot water reaches the set liquid level, the end water pump 20 is closed. When the water temperature is lower than the set hot water temperature, the end return valve 28 is opened, and the water is returned to the hot water ring line 18 through the end return valve 28 driven by the water supply pump 27.

[0066] The hot water ring line 18 can be connected to multiple demand side modules at the same time, forming a ring-shaped water supply structure, increasing the utilization rate of waste heat resources and the heating range.

[0067] The hot water ring line system of the combined area multi-air compression station waste heat resource heat recovery is based on the supply side and the hot water ring line, and can be divided into a heat storage mode, a supply mode, a mixed mode, a shutdown mode, and a ring line return water reheating mode. Based on the demand side and the hot water ring line, it can be divided into a direct water supply mode, a reheated water mode, and a waste water recovery mode. The various operation modes of the supply side module-hot water ring line and the demand side module-hot water ring line can be combined to form multiple operation modes, so as to achieve the lowest comprehensive energy consumption and the highest cost saving rate while meeting the demand side water demand.

[0068] The operation mode based on the supply side and the hot water ring line and the operation mode based on the demand side and the hot water ring line will be described below:

[0069] The hot water ring line system of the combined area multi-air compression station waste heat resource heat recovery is based on the supply side and the hot water ring line, and has a heat storage mode, a supply mode, a mixed mode, a shutdown mode, and a ring line return water reheating mode.

[0070] The heat storage mode: The cooling water in the supply side module driven by the cooling water pump 3 to absorb the heat of the air compressor 1 is adjusted by the frequency conversion pump 5, part of which enters the plate heat exchanger 6 to preheat the cold water entering the plate heat exchanger 6 driven by the cold water pump 4, and the preheated water enters the total water tank 11 through the water supplement valve 8. The cooled cooling water returns to the cooling tower 2 and then to the air compressor 1. The other part of the cooling water enters the water source heat pump unit 7 and is cooled in the evaporator of the water source heat pump unit 7 to return to the cooling tower 2 and then to the air compressor 1. The water in the total water tank 11 is driven by the return water pump 13 to enter the water source heat pump unit 7 through the return water valve 12, and is further heated to return to the total water tank 11. The target water level and temperature of the total water tank 11 are adjusted according to the actual demand. When the water temperature detected by the total water tank temperature sensor 9 meets the set value of the water supply and heat preservation demand, and the liquid level in the water tank 11 detected by the total water tank liquid level sensor 10 reaches the set value, the cold water pump 4 is closed, the water supplement valve 8 is closed, the return water pump 13 is closed, the return water valve 12 is closed, and the water source heat pump unit 7 is shut down.

[0071] Supply mode: the water tank level sensor 10 in the supply side module detects the presence of water source in the water tank 11, the total water tank temperature sensor 9 detects that the water temperature meets the water supply demand setting value, when the demand side module has hot water demand or the hot water ring line 18 needs to be replenished, the water supply valve 14 is opened, the water supply water pump 15 drives the hot water in the total water tank 11 to enter the hot water ring line 18, the target water level and water temperature of the total water tank 11 are adjusted according to the actual demand, when the total water tank level sensor 10 detects that the liquid level in the total water tank 11 is reduced to below the set minimum liquid level, the water supply valve 14 and the water supply water pump 15 are closed, the supply side switches back to the heat storage mode, the water temperature detected by the total water tank temperature sensor 9 meets the water supply and heat preservation demand setting value, and the total water tank level sensor 10 detects that the liquid level in the water tank 11 reaches the set value, then it is switched to the supply mode again until the demand is met. The hot water produced by recycling various waste heat resources is sent into the hot water ring line 18, and the circulation of hot water in the ring line is realized by the circulation water pump 31. Due to the large specific heat capacity of water, appropriate heat preservation measures are taken for the pipeline, even if there is some heat loss in the flow process, but due to the newly added hot water at each point, the temperature of the mixed water is also increased, which improves the stability of the water temperature in the ring line.

[0072] Mixed mode: the cooling water in the supply side module driven by the cooling water pump 3 absorbs the heat of the air compressor 1, and after the adjustment of the frequency conversion pump 5, part of it enters the plate heat exchanger 6 to preheat the cold water entering the plate heat exchanger 6 driven by the cold water pump 4, the preheated water enters the total water tank 11 through the water replenishment valve 8, the water supply valve 14 and the water return valve 12 are opened, part of the water is directly sent to the hot water ring line 18 through the water supply valve 14 driven by the water supply water pump 15, and the other part is heated in the water source heat pump unit 7 and then returned to the total water tank 11 through the water return valve 12 driven by the water return water pump 13, at this time the mixed water temperature in the total water tank 11 is increased, and the above process is repeated, part of it is sent to the water source heat pump unit 7 for reheating, and the other part is directly sent to the hot water ring line 18, when the demand is met, the system switches to the heat storage or shutdown mode. The hot water produced by recycling various waste heat resources is sent into the hot water ring line 18, and the circulation of hot water in the ring line is realized by the circulation water pump 31. Due to the large specific heat capacity of water, appropriate heat preservation measures are taken for the pipeline, even if there is some heat loss in the flow process, but due to the newly added hot water at each point, the temperature of the mixed water is also increased, which improves the stability of the water temperature in the ring line.

[0073] Shutdown mode: the air compressor 1 is shutdown or no waste heat, or waste heat resource generation time is peak or peak time, there may be water source heat pump unit 7 does not work the best case of comprehensive energy saving and cost saving effect, at this time the water source heat pump unit 7 is shutdown, in shutdown mode, if the user side has water demand or hot water ring line 18 needs to replenish water, water supply valve 14, water supply pump 15 is opened, when the total water tank 11 liquid level sensor 10 senses that the total water tank 11 has water storage, the water in the total water tank 11 is driven by the water supply pump 15, through the water supply valve 14 to the hot water ring line 18, when the total water tank 11 liquid level sensor 10 senses that the total water tank 11 liquid level is reduced, the cold water pump 4 is opened, the water replenishment valve 8, the cold water pump 4 drives the water to enter the total water tank 11 through the water replenishment valve 8, and then sent to the hot water ring line 18, because the hot water produced by each waste heat resource recovery is sent into the hot water ring line 18, the circulation of the hot water in the ring line is realized by the circulation pump, because the specific heat capacity of water is large, the pipeline adopts appropriate heat preservation measures, the water replenished can also be mixed to increase the temperature, which improves the stability of the water temperature in the ring line.

[0074] Ring line backwater reheating mode: this mode corresponds to the situation that the supply side waste heat resource exists but the ring line water temperature is low, the ring line recovery pump 16 of the part of the supply side module is started, the ring line recovery valve 17 is opened, the water in the hot water ring line 18 is driven by the ring line recovery pump 16, passes through the ring line recovery valve 17, and is reheated in the water source heat pump unit 7, and then is sent into the total water tank 11, when the temperature sensor 9 and the liquid level sensor 10 of the total water tank 11 sense that the water temperature and the liquid level meet the requirements, the water supply pump 15 and the water supply valve 14 are opened, and the hot water is transported into the hot water ring line 18. This mode can be operated synchronously with the supply mode, and the water resource waste is reduced through ring line water recovery and reheating.

[0075] The hot water ring line system combined with the waste heat resource heat recovery of the multiple air compression station has a direct water supply mode, a reheated water mode, and a waste water recovery mode based on the demand side and the hot water ring line.

[0076] Direct water supply mode: the user end 30 sets the target water level and water temperature of the terminal water tank 26 according to the load demand, when the hot water temperature in the hot water ring line 18 detected by the water replenishment temperature sensor 19 of the demand side module meets the demand, the terminal water supply pump 20 is started, the reheat water valve 21 is closed, the air source heat pump unit 23 is stopped, the direct water supply valve 22 is opened, the hot water in the hot water ring line 18 flows into the terminal water tank 26 through the direct water supply valve 22 driven by the terminal water supply pump 21, when the water temperature and liquid level in the terminal water tank 26 detected by the terminal temperature sensor 24 and the terminal liquid level sensor 26 meet the demand, the direct water supply valve 22 and the terminal water supply pump 27 are closed, when the user end 30 uses water, the water supply valve 29 is opened, the water supply pump 27 is started, the terminal return valve 28 is closed, the water supply pump 27 drives the hot water in the terminal water tank 26 to flow to the user end 30 through the water supply valve 29. This mode can store hot water through the water tank while delivering hot water, improving the utilization rate of hot water ring line direct hot water supply.

[0077] Reheat water mode: the user end 30 sets the target water level and water temperature of the terminal water tank 26 according to the load demand, when the hot water temperature in the hot water ring line 18 detected by the water replenishment temperature sensor 24 of the demand side module does not meet the demand, but the user end 30 needs hot water, or the terminal water tank 26 needs to store hot water in advance, the terminal water supply pump 20 is started, the reheat water valve 21 is opened, the air source heat pump unit 23 is started, the direct water supply valve 22 is closed, the hot water in the ring line 18 flows into the air source heat pump unit 23 through the reheat water valve 21 driven by the terminal water supply pump 20, and then enters the terminal water tank 26 after being further heated by the air source heat pump unit 23, when the water temperature and liquid level in the terminal water tank 26 detected by the terminal temperature sensor 24 and the terminal liquid level sensor 25 meet the demand, the reheat water valve 21 and the terminal water supply pump 20 are closed, when the user end 30 uses water, the water supply valve 29 is opened, the water supply pump 27 is started, the water supply pump 27 drives the hot water in the terminal water tank 26 to flow to the user end 30 through the water supply valve 29. In the reheat mode, the water in the hot water ring line 18 is higher than the normal cold water temperature, which can reduce the energy consumption of the air source heat pump unit 23.

[0078] Excess water recovery mode: When the end tank water level sensor 25 of the demand side module senses that there is excess water in the end tank 26, but the end tank temperature sensor 24 senses that the water in the end tank 26 does not meet the demand temperature, the water supply pump 27 is turned on, the end return valve 28 is opened, and the water supply valve 29 is closed. The excess water in the end tank 26 is driven by the water supply pump 27 to return to the hot water ring line 18 through the end return valve 28. At this time, compared with the hot water in the ring line 18, the amount of excess water is less, the mixed water temperature is higher, and it is possible to directly meet the temperature demand of the water supply. Even if it does not meet, the air source heat pump reheat water mode or the ring line return water reheat mode can be started to reheat the water. The excess water recovery mode reduces water resource waste and reduces hot water energy consumption through reasonable pipeline arrangement and control mode.

[0079] The pipeline arrangement and material of the hot water ring line in the above embodiment should be adapted to the local conditions. Since the actual conditions of different regions are different, they are not specifically described. The improvement of the arrangement of the hot water ring line and the pipeline material cannot be considered as a substantial improvement of the present application. The above embodiment takes the waste heat resource of the air compressor as an example. For other centralized waste heat resources, it cannot be considered as a substantial improvement of the present application. At the same time, in the recovery mode of waste heat resources, the water source heat pump is taken as an example. According to the nature of different waste heat resources, the corresponding suitable heat pump unit can be selected to complete the function of absorbing waste heat to produce hot water. The selection of different heat pump units to adapt to corresponding waste heat resources or the series and parallel connection of different heat pump units, as well as the selection and series and parallel connection of air source heat pump units, the change of the specification and quantity of water tanks, cannot be considered as a substantial improvement of the present application, and should be within the protection scope of the present application.

[0080] The above description of the embodiments is for the convenience of the ordinary skilled person in the art to understand and use the invention. Those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described herein to other embodiments without creative labor. Therefore, the present application is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art according to the disclosure of the present application without departing from the scope of the present application should be within the protection scope of the present application.

Claims

1. A hot water loop system integrating waste heat recovery from multiple regional air compressor stations, characterized in that, Includes supply-side module, hot water loop (18), and demand-side module; The supply-side module includes a heat-exchange connected air compressor cooling water circuit, a first water tank storage-supply flow path, and a return flow path; The hot water loop (18) is connected to the water tank storage-supply flow path; The return water flow path is used for the return water from the hot water loop (18) to the first water tank storage-supply flow path; The demand-side module includes a second water tank storage-supply flow path and a user terminal (30) that are interconnected. The second water tank storage-supply flow path is connected to the hot water loop (18). Multiple supply-side modules are provided along the hot water loop (18), and multiple demand-side modules are provided along the hot water loop (18); The air compressor cooling water circuit includes an air compressor (1), a cooling water pump (3), a variable frequency pump (5), a first heat exchange channel of a plate heat exchanger (6), and a cooling tower (2) connected in sequence. The air compressor cooling water circuit also includes a first heat exchange channel of a water source heat pump unit (7), one end of which is connected to the cooling water pump (3) and the other end is connected to the cooling tower (2). The first water tank storage-supply flow path includes a cold water pump (4), a second heat exchange channel of a plate heat exchanger (6), a water supply valve (8), a main water tank (11), a water supply valve (14), and a water supply pump (15) connected in sequence. The water supply pump (15) is connected to the hot water loop (18). The first water tank storage-supply flow path also includes a return water valve (12), a return water pump (13), and a second heat exchange channel of a water source heat pump unit (7) connected in sequence. The return water valve (12) is connected to the main water tank (11), and the second heat exchange channel of the water source heat pump unit (7) is connected to the main water tank (11). The return water flow path includes a loop recovery valve (17) and a loop recovery pump (16) connected in sequence. The loop recovery valve (17) is connected to the hot water loop (18), and the loop recovery pump (16) is connected to the water source heat pump unit (7). The main water tank (11) includes a main water tank temperature sensor (9) and a main water tank level sensor (10). The second water tank storage-supply flow path includes a terminal water pump (20), a reheat valve (21), an air source heat pump unit (23), a terminal water tank (26), a water supply pump, and a water supply valve (29) connected in sequence. The water pump (20) is connected to the hot water loop (18), and the water supply valve (29) is connected to the user terminal (30). The second water tank storage-supply flow path also includes a direct delivery valve (22), one end of which is connected to the end water pump (20), and the other end is connected to the end water tank (26); The second water tank storage-supply flow path also includes an end return valve (28), one end of which is connected to the water supply pump and the other end is connected to the hot water loop (18); The terminal water tank (26) is equipped with a terminal water tank temperature sensor and a terminal water tank level sensor (25). The inlet end of the terminal water pump (20) is equipped with a water supply temperature sensor (19).

2. A hot water loop system combining waste heat recovery from multiple regional air compressor stations as described in claim 1, characterized in that, During actual operation, the cooling water pump (3) drives the cooling water that has absorbed the heat of the air compressor (1). Through the action of the variable frequency pump (5), a portion of the cooling water enters the plate heat exchanger (6) to exchange heat with the cold water driven by the cold water pump (4). The preheated cold water enters the main water tank (11) through the water supply valve (8). After passing through the plate heat exchanger (6), the cooling water returns to the cooling tower (2) and then returns to the air compressor (1). Another portion of the cooling water enters the water source heat pump unit (7). After being cooled in the unit, the cooling water returns to the air compressor (1). The preheated water in the main water tank (11) is driven by the return water pump (13), passes through the return water valve (12), enters the water source heat pump unit (7), is reheated to the specified temperature, and is sent back to the main water tank (11). The water in the main water tank (11) is driven by the water pump (15), passes through the water valve (14), and is sent to the hot water loop (18).

3. A hot water loop system combining waste heat recovery from multiple regional air compressor stations as described in claim 1, characterized in that, During actual operation, depending on the water temperature sensed by the water supply temperature sensor (19), the hot water driven by the terminal water pump (20) can be sent into the terminal water tank (26) through the direct delivery valve (22), or enter the air source heat pump unit (23) through the reheat valve (21). After the water is reheated, it is sent into the terminal water tank (26). The hot water in the terminal water tank (26) is sent to the user end (30) through the water supply valve (29) driven by the water supply pump. When the delivered hot water reaches the set liquid level of the terminal water tank (26), the terminal water pump (20) is turned off. When the water temperature is lower than the set hot water temperature, the terminal return valve (28) is opened. The water returns to the hot water loop (18) through the terminal return valve (28) driven by the water pump.

4. A hot water loop system combining waste heat recovery from multiple regional air compressor stations as described in claim 1, characterized in that, When the entire system operates in heat storage mode: In the supply-side module, the cooling water pump (3) drives the cooling water that absorbs heat from the air compressor (1). After being regulated by the variable frequency pump (5), a portion of the cooling water enters the plate heat exchanger (6) to preheat the cold water driven by the cold water pump (4) into the plate heat exchanger (6). The preheated water enters the main water tank (11) through the water supply valve (8). The cooled water after heat exchange returns to the cooling tower (2) and then back to the air compressor (1). Another portion of the cooling water enters the water source heat pump unit (7), dissipates heat in the evaporator of the water source heat pump unit (7), and then returns to the cooling tower (2) and then back to the air compressor (1). The water in the main water tank (11) is driven by the return water pump (13) and enters the water source heat pump unit (7) through the return water valve (12). After being further heated, it returns to the main water tank (11). When the water temperature detected by the main water tank temperature sensor (9) meets the set value for water supply and heat preservation, and when the liquid level sensor (10) of the main water tank detects that the liquid level in the water tank (11) reaches the set value, the cold water pump (4) is shut down, the water supply valve is shut down, the return water pump (13) is shut down, the return water valve (12) is shut down, and the water source heat pump unit (7) is shut down. When the overall system operates in supply mode: The water tank level sensor (10) in the supply-side module detects that there is water in the water tank (11), and the total water tank temperature sensor (9) detects that the water temperature meets the water delivery demand setting value. When the demand-side module has hot water demand or the hot water loop (18) needs to be replenished, the water supply valve (14) is opened, and the water supply pump (15) drives the hot water in the total water tank (11) to be delivered into the hot water loop (18). The target water level and water temperature of the total water tank (11) are adjusted according to actual needs. When the total water tank level sensor (10) detects that the liquid level in the total water tank (11) drops below the set minimum liquid level, the water supply valve (14) and the water supply pump (15) are closed, and the supply side switches back to the heat storage mode. When the water temperature detected by the total water tank temperature sensor (9) meets the water delivery and heat preservation demand setting value, and when the total water tank level sensor (10) detects that the liquid level in the water tank (11) reaches the set value, it switches back to the supply mode until the demand is met.

5. A hot water loop system combining waste heat recovery from multiple regional air compressor stations according to claim 1, characterized in that, When the overall system runs in hybrid mode: In the supply-side module, the cooling water pump (3) drives the cooling water that absorbs heat from the air compressor (1). After the regulation of the variable frequency pump (5), part of the water enters the plate heat exchanger (6) to preheat the cold water driven by the cold water pump (4) into the plate heat exchanger (6). The preheated water enters the main water tank (11) through the water supply valve (8). The water supply valve (14) and the return water valve (12) are opened. Part of the water is directly sent to the hot water loop (18) through the water supply valve (14) driven by the water supply pump (15). Another part is sent to the water source heat pump unit (7) for reheating through the return water valve (12) driven by the return water pump (13) and then returned to the main water tank (11). At this time, the temperature of the mixed water in the main water tank (11) rises. Part of the water is sent to the water source heat pump unit (7) for reheating, and the other part is sent directly to the hot water loop (18). When the demand is met, the system switches to the heat storage or shutdown mode.

6. A hot water loop system combining waste heat recovery from multiple regional air compressor stations according to claim 1, characterized in that, When the entire system operates in loop reheat mode: The loop recovery pump (16) of the partial supply-side module is started, and the loop recovery valve (17) is opened. The water in the hot water loop (18) is driven by the loop recovery pump (16), passes through the loop recovery valve (17) and returns to the water source heat pump unit (7) for reheating, and then is sent to the main water tank (11). When the temperature sensor (9) and liquid level sensor (10) of the main water tank (11) sense that the water temperature and liquid level meet the requirements, the water pump (15) and water valve (14) are opened, and the hot water is delivered into the hot water loop (18).

7. A hot water loop system combining waste heat recovery from multiple regional air compressor stations according to claim 1, characterized in that, When the entire system operates in direct water supply mode: The user terminal (30) sets the target water level and water temperature of the terminal water tank (26) according to the load demand. When the water supply temperature sensor (19) of the demand side module detects that the hot water temperature in the hot water loop (18) meets the demand, the terminal water pump (20) is turned on, the reheat valve is closed, the air source heat pump unit (23) is stopped, and the direct water supply valve (22) is turned on. The hot water in the hot water loop (18) flows into the terminal water tank (26) through the direct water supply valve (22) driven by the terminal water pump. When the terminal temperature sensor and terminal liquid level sensor of the terminal water tank (26) detect that the water temperature and liquid level in the terminal water tank meet the demand, the direct water supply valve (22) and the terminal water pump are turned off. When the user terminal (30) uses water, the water supply valve (29) is turned on, the water supply pump is turned on, and the terminal return water valve (28) is turned off. The water supply pump drives the hot water in the terminal water tank (26) through the water supply valve (29) to be sent to the user terminal (30). When the entire system is running in reheat mode: The user terminal (30) sets the target water level and water temperature of the terminal water tank (26) according to the load demand. When the water supply temperature sensor of the demand-side module detects that the hot water temperature in the hot water loop (18) does not meet the demand, but the user terminal (30) needs hot water, or the terminal water tank (26) needs to store hot water in advance, the terminal water pump (20) is turned on, the reheat valve (21) is turned on, the air source heat pump unit (23) is turned on, and the direct water supply valve (22) is turned off. The hot water in the hot water loop (18) is driven by the terminal water pump (20) and passes through the reheat valve (21). 21) The water flows into the air source heat pump unit (23), and after being further heated by the air source heat pump unit (23), it enters the terminal water tank (26). When the terminal temperature sensor and terminal liquid level sensor of the terminal water tank (26) detect that the water temperature and liquid level in the terminal water tank (26) meet the requirements, the reheat valve (21) and the terminal water pump (20) are closed. When the user (30) uses water, the water supply valve (29) is opened and the water supply pump is turned on. The water supply pump drives the hot water in the terminal water tank (26) to be sent to the user (30) through the water supply valve (29). When the entire system operates in waste water recovery mode: When the water level sensor of the terminal water tank of the demand-side module senses that there is residual water in the terminal water tank (26), but the water temperature sensor of the terminal water tank senses that the water in the terminal water tank (26) does not meet the required temperature, the water supply pump is turned on, the terminal return valve (28) is turned on, the water supply valve (29) is turned off, and the water supply pump drives the residual water in the terminal water tank (26) to return to the hot water loop (18) through the terminal return valve (28).

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