Low-temperature refrigeration waste heat recovery system

Abstract

The utility model relates to the technical field of waste heat recovery, in particular to a low-temperature refrigeration waste heat recovery system which comprises a hot water circulating pump provided with a first outlet and a first inlet, and further comprises a heat pump unit comprising a heat pump unit condenser and a heat pump unit evaporator. The heat pump unit condenser is provided with a second outlet and a second inlet, the first outlet of the hot water circulating pump is communicated with the second inlet of the heat pump unit evaporator, and the heat pump unit evaporator is provided with a third outlet and a third inlet. After waste heat is recovered, the heat dissipation load of the evaporative condenser is reduced, and meanwhile the operation condensation pressure of the refrigerating unit can be remarkably reduced; refrigerant gas and evaporative condenser spray water waste heat can be recovered through waste heat recovery, the recovered heat is used for heating process production water, the energy consumption of steam, natural gas, electric energy and the like is reduced, and the purposes of energy conservation and consumption reduction are achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of waste heat recovery, especially to low-temperature refrigeration waste heat recovery system. BACKGROUND

[0002] The low-temperature refrigeration system usually adopts ammonia refrigeration system or fluorine refrigeration system, and the high-temperature and high-pressure refrigerant gas is transported to the evaporative condenser through the pipeline for condensation and heat dissipation.

[0003] The existing evaporative condenser heat exchange pipe outer wall scales seriously, which leads to that the heat dissipation far fails to reach the rated value, especially in the summer high temperature and high humidity weather, the refrigerating unit is operated in the high pressure working condition for a long time, and the high-temperature refrigerant gas contains a large amount of heat, which is not utilized and finally discharged to the atmosphere, which is not conducive to energy saving and consumption reduction. UTILITY MODEL CONTENTS

[0004] The utility model discloses a low-temperature refrigeration waste heat recovery system, which solves the problem of heat energy loss of the condenser in the prior art.

[0005] In order to realize the above-mentioned purpose, the utility model adopts the following technical scheme:

[0006] The low-temperature refrigeration waste heat recovery system comprises a hot water circulating pump, a first outlet and a first inlet are arranged on the hot water circulating pump, and further comprises:

[0007] The heat pump unit comprises a heat pump unit condenser and a heat pump unit evaporator, a second outlet and a second inlet are arranged on the heat pump unit condenser, the first outlet of the hot water circulating pump is communicated with the second inlet of the heat pump unit evaporator, and a third outlet and a third inlet are arranged on the heat pump unit evaporator;

[0008] A heat source water circulating pump is arranged, a fourth outlet and a fourth inlet are arranged on the heat source water circulating pump, and the heat source water circulating pump is communicated with the third inlet of the heat pump unit evaporator through the fourth outlet;

[0009] A water tank is arranged, the hot water circulating pump is communicated with the water tank through the first inlet, and the heat pump unit condenser is communicated with the water tank through the second outlet.

[0010] The tap water preheating plate heat exchanger is provided with a low-temperature side inlet, a low-temperature side outlet, a high-temperature side inlet and a high-temperature side outlet, tap water is connected into the tap water preheating plate heat exchanger through the low-temperature side inlet, and the low-temperature side outlet of the tap water preheating plate heat exchanger is communicated with a water tank;

[0011] The refrigerant heat recovery device is provided with a first water outlet, a first water inlet, a first gas outlet and a first gas inlet, the refrigerant heat recovery device is communicated with the high-temperature side inlet of the tap water preheating plate heat exchanger through the first water outlet, and the refrigerant heat recovery device is connected with the gas inlet pipeline for conveying high-temperature refrigerant gas through the first gas inlet;

[0012] The refrigerant heat recovery valve is installed on the gas inlet pipeline;

[0013] The refrigerant direct discharge valve is installed on the gas inlet pipeline;

[0014] The evaporative condenser is provided with a second gas inlet, a water tank water outlet and a water tank water inlet for conveying water flow, the evaporative condenser is communicated with the fourth inlet on the heat source water circulating pump through the water tank water outlet, the evaporative condenser is communicated with the third outlet on the evaporator of the heat pump unit through the water tank water inlet, and the evaporative condenser is communicated with the first gas outlet on the refrigerant heat recovery device through the second gas inlet.

[0015] Preferably, the tap water preheating plate heat exchanger and the refrigerant heat recovery device are connected with a heat recovery circulating pump, the heat recovery circulating pump is provided with a fifth outlet and a fifth inlet, the refrigerant heat recovery device is communicated with the fifth outlet on the heat recovery circulating pump through the first water inlet, and the heat recovery circulating pump is communicated with the high-temperature side outlet of the tap water preheating plate heat exchanger through the fifth inlet.

[0016] Preferably, the heat recovery circulating pump is provided with a conveying pipeline for connecting the tap water preheating plate heat exchanger and the refrigerant heat recovery device.

[0017] Preferably, an electric regulating valve is arranged between the low-temperature side outlet of the tap water preheating plate heat exchanger and the water tank.

[0018] Preferably, the water tank is further provided with a liquid level sensor matched with the electric regulating valve.

[0019] Preferably, the refrigerant heat recovery device and the heat pump unit respectively realize waste heat of refrigerant gas and waste heat of spraying water of the evaporative condenser.

[0020] Compared with the prior art, the utility model has the following advantages:

[0021] 1. The utility model discloses a refrigerant gas and the waste heat of evaporative condenser spray water can be recycled, which can greatly reduce the heat dissipation load of the evaporative condenser, reduce the operation time of the condenser cooling fan and reduce the operation cost.

[0022] 2. The utility model discloses a waste heat recovery system, which can reduce the operation condensing pressure of the refrigerating unit, improve the operation efficiency of the refrigerating unit and reduce the operation energy consumption while reducing the heat dissipation load of the evaporative condenser.

[0023] 3. The utility model discloses a waste heat recovery system, which can recycle the refrigerant gas and the waste heat of evaporative condenser spray water, recycle the heat for process water heating, reduce the energy consumption of steam, natural gas and electricity and achieve the purpose of energy saving and consumption reduction.

[0024] 4. The utility model discloses a water tank and a refrigerant heat recovery device, which can effectively prevent the refrigerant gas leakage from polluting the water stored in the water tank, and the circulating water pipeline between the secondary heat exchanger and the heat recovery device is a closed cycle, and the pipeline is filled with pure water, which can completely prevent the heat exchanger from scaling and ensure the best heat exchange effect.

[0025] 5. The utility model discloses a heat pump unit, which can transfer the heat absorbed from the spray water tank to the hot water tank through the reverse Carnot cycle, and the energy efficiency ratio of the heat pump unit is above 4.0, which has a significant energy saving effect. BRIEF DESCRIPTION OF DRAWINGS

[0026] Fig. 1 The utility model discloses a low-temperature refrigeration waste heat recovery system structure schematic view.

[0027] Fig. 2 The utility model discloses a low-temperature refrigeration waste heat recovery system refrigerant heat recovery device, refrigerant heat recovery valve, refrigerant direct discharge valve process flow chart.

[0028] In the drawing: 1, hot water circulating pump; 2, heat pump unit; 3, heat source water circulating pump; 4, water tank; 5, tap water preheating plate heat exchanger; 6, heat recovery circulating pump; 7, refrigerant heat recovery device; 8, refrigerant heat recovery valve; 9, refrigerant direct discharge valve; 10, evaporative condenser; 11, electric regulating valve; 12, liquid level sensor. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments.

[0030] Reference Figs. 1-2, low-temperature refrigeration waste heat recovery system, comprising a hot water circulating pump 1, and the hot water circulating pump 1 is provided with a first outlet and a first inlet, further comprising a heat pump unit 2, a heat source water circulating pump 3, a water tank 4, a tap water preheating plate exchanger 5, a refrigerant heat recovery device 7, a refrigerant heat recovery valve 8, a refrigerant direct discharge valve 9, and an evaporative condenser 10:

[0031] The heat pump unit 2 comprises a heat pump unit condenser and a heat pump unit evaporator, the heat pump unit condenser is provided with a second outlet and a second inlet, and the first outlet of the hot water circulating pump 1 is in communication with the second inlet of the heat pump unit evaporator, the heat pump unit evaporator is provided with a third outlet and a third inlet, by dividing the heat pump unit 2 into the heat pump unit condenser and the heat pump unit evaporator, the heat pump unit condenser can cool and transport the water vapor flowing in, further reducing the heat dissipation load of the evaporative condenser 10, and the heat pump unit evaporator can concentrate and absorb the heat energy of the water vapor, further reducing the operation time of the heat dissipation fan and effectively reducing the operation cost.

[0032] The heat source water circulating pump 3 is provided with a fourth outlet and a fourth inlet, and the heat source water circulating pump 3 is in communication with the third inlet of the heat pump unit evaporator through the fourth outlet, and by connecting the fourth outlet of the heat source water circulating pump 3 with the water tank outlet of the evaporative condenser 10, the hot water vapor generated by the evaporative condenser 10 during operation can be quickly collected by the heat source water circulating pump 3.

[0033] The hot water circulating pump 1 is in communication with the water tank 4 through the first inlet, and the heat pump unit condenser is in communication with the water tank 4 through the second outlet.

[0034] The tap water preheating plate exchanger 5 is provided with a low-temperature side inlet, a low-temperature side outlet, a high-temperature side inlet and a high-temperature side outlet, the tap water preheating plate exchanger 5 is connected to tap water through the low-temperature side inlet, and the low-temperature side outlet of the tap water preheating plate exchanger 5 is in communication with the water tank 4.

[0035] An electric regulating valve 11 is arranged between the low-temperature side outlet of the tap water preheating plate exchanger 5 and the water tank 4, and a liquid level sensor 12 matched with the electric regulating valve 11 is further arranged on the water tank 4, the liquid level sensor 12 can monitor the water quantity in the water tank 4 and compare it with the system set value, and the water quantity level is controlled through the electric regulating valve 11.

[0036] The refrigerant heat recovery device 7 and the heat pump unit 2 respectively realize the waste heat of refrigerant gas and the waste heat of the spray water of the evaporative condenser 10, the tap water can be transported through the low-temperature side inlet and the low-temperature side outlet, and the flowing hot water can be transported through the high-temperature side inlet and the high-temperature side outlet, thereby realizing the circulating flow of the water in the water tank 4.

[0037] The heat recovery circulating pump 6 is provided with a fifth outlet and a fifth inlet, the refrigerant heat recovery device 7 is connected with the fifth outlet of the heat recovery circulating pump 6 through a first water inlet, and the heat recovery circulating pump 6 is connected with the high-temperature side outlet of the tap water preheating plate heat exchanger 5 through the fifth inlet.

[0038] The heat recovery circulating pump 6 is provided with a conveying pipeline for connecting the tap water preheating plate heat exchanger 5 and the refrigerant heat recovery device 7, indirect heat exchange between the water tank 4 and the refrigerant heat recovery device 7 through the secondary heat exchanger can effectively avoid pollution of water stored in the water tank 4 caused by refrigerant gas leakage, and the circulating water pipeline between the secondary heat exchanger and the heat recovery device is a closed circulation, so that scale formation can be avoided, and the heat exchanger can achieve the best heat exchange effect.

[0039] The refrigerant heat recovery device 7 is provided with a first water outlet, a first water inlet, a first gas outlet and a first gas inlet, the refrigerant heat recovery device 7 is connected with the high-temperature side inlet of the tap water preheating plate heat exchanger 5 through the first water outlet, and the refrigerant heat recovery device 7 is connected with the gas inlet pipeline for conveying high-temperature refrigerant gas through the first gas inlet.

[0040] The refrigerant heat recovery valve 8 is installed on the gas inlet pipeline.

[0041] The refrigerant direct discharge valve 9 is installed on the gas inlet pipeline, and it is specified that, according to the description and the drawings, Fig. 2 When the evaporative condenser 10 operates, the refrigerant direct discharge valve 9 is closed, the refrigerant heat recovery valve 8 is opened, and the heat loss can be effectively reduced; when the waste heat recovery system is not used, the refrigerant direct discharge valve 9 is opened, the refrigerant heat recovery valve 8 is closed, and the original process circulation is operated.

[0042] The evaporative condenser 10 is provided with a second gas inlet, a water tank water outlet and a water tank water inlet for conveying water flow, the evaporative condenser 10 is connected with the fourth inlet of the heat source water circulating pump 3 through the water tank water outlet, the evaporative condenser 10 is connected with the third outlet of the heat pump unit evaporator through the water tank water inlet, and the evaporative condenser 10 is connected with the first gas outlet of the refrigerant heat recovery device 7 through the second gas inlet.

[0043] The hot water vapor generated by the evaporative condenser 10 is collected, the heat dissipation degree of the evaporative condenser 10 is improved, the heat dissipation fan can reduce the operation time when dissipating heat of the evaporative condenser 10, the collected water vapor is collected and used, the recovered heat energy can heat process water, and the energy consumption of energy sources such as energy-saving power sources is reduced.

[0044] The utility model can be described by the following operation modes to explain the function principle:

[0045] When the evaporative condenser 10 is running, the heat energy is generated, the refrigerant direct discharge valve 9 is closed, the refrigerant heat recovery valve 8 is opened, the high-temperature refrigerant gas is transported through the air inlet pipe and participates in the heat recovery exchange;

[0046] The water vapor generated by the heat energy of the evaporative condenser 10 is transported to the heat source water circulating pump 3 through the water tank outlet;

[0047] After the heat source water circulating pump 3 is started, the water vapor flows into the heat pump unit, the heat pump unit condenser cools the water vapor and transports the water flow into the water tank 4, and the water flow is transported into the tap water preheating plate heat exchanger 5 to perform the exchange operation;

[0048] The heat pump unit evaporator absorbs the heat energy in the water vapor and transports it into the evaporative condenser 10 through the water tank inlet, thereby reducing the heat dissipation load of the evaporative condenser 10;

[0049] The control system compares the liquid level value detected by the liquid level sensor 12 with the set value, adjusts the opening degree of the electric regulating valve 11 through the PID, and controls the constant liquid level;

[0050] The recovered heat is used for heating the process water, and the highest hot water temperature reaches 65 DEG C, which can fully meet the temperature requirement of the process water.

[0051] The above is only the preferred specific implementation mode of the present application, but the protection scope of the present application is not limited to this, any skilled person in the technical field according to the technical scheme and the utility model concept of the present application within the technical range disclosed by the present application can be equivalent to replace or change, which should be covered in the protection scope of the present application.

Claims

1. A low-temperature refrigeration waste heat recovery system, comprising a hot water circulating pump (1), and a first outlet and a first inlet are arranged on the hot water circulating pump (1), characterized in that, Also comprising: a heat pump unit (2) comprising a heat pump unit condenser and a heat pump unit evaporator, the heat pump unit condenser being provided with a second outlet and a second inlet, and the first outlet of the hot water circulating pump (1) being in communication with the second inlet of the heat pump unit evaporator, the heat pump unit evaporator being provided with a third outlet and a third inlet; a heat source water circulating pump (3) being provided with a fourth outlet and a fourth inlet, and the heat source water circulating pump (3) being in communication with the third inlet of the heat pump unit evaporator through the fourth outlet; a water tank (4), the hot water circulating pump (1) being in communication with the water tank (4) through the first inlet, and the heat pump unit condenser being in communication with the water tank (4) through the second outlet; a tap water preheating plate heat exchanger (5) being provided with a low-temperature side inlet, a low-temperature side outlet, a high-temperature side inlet and a high-temperature side outlet, the tap water preheating plate heat exchanger (5) being connected to tap water through the low-temperature side inlet, and the low-temperature side outlet of the tap water preheating plate heat exchanger (5) being in communication with the water tank (4); a refrigerant heat recovery device (7) being provided with a first water outlet, a first water inlet, a first gas outlet and a first gas inlet, the refrigerant heat recovery device (7) being in communication with the high-temperature side inlet of the tap water preheating plate heat exchanger (5) through the first water outlet, and the refrigerant heat recovery device (7) being connected to a gas inlet pipeline for conveying high-temperature refrigerant gas through the first gas inlet; a refrigerant heat recovery valve (8) being installed on the gas inlet pipeline; a refrigerant direct discharge valve (9) being installed on the gas inlet pipeline; an evaporative condenser (10) being provided with a second gas inlet and a water tank water outlet and a water tank water inlet for conveying water flow, the evaporative condenser (10) being in communication with the fourth inlet of the heat source water circulating pump (3) through the water tank water outlet, the evaporative condenser (10) being in communication with the third outlet of the heat pump unit evaporator through the water tank water inlet, and the evaporative condenser (10) being in communication with the first gas outlet of the refrigerant heat recovery device (7) through the second gas inlet.

2. The cryogenic refrigeration waste heat recovery system of claim 1, wherein, A heat recovery circulating pump (6) is connected between the tap water preheating plate heat exchanger (5) and the refrigerant heat recovery device (7), the heat recovery circulating pump (6) being provided with a fifth outlet and a fifth inlet, the refrigerant heat recovery device (7) being in communication with the fifth outlet of the heat recovery circulating pump (6) through the first water inlet, and the heat recovery circulating pump (6) being in communication with the high-temperature side outlet of the tap water preheating plate heat exchanger (5) through the fifth inlet.

3. The cryogenic refrigeration waste heat recovery system of claim 2, wherein, The heat recovery circulating pump (6) is provided with a conveying pipeline for connecting the tap water preheating plate heat exchanger (5) and the refrigerant heat recovery device (7).

4. The cryogenic refrigeration waste heat recovery system of claim 1, wherein, An electric regulating valve (11) is arranged between the low-temperature side outlet of the tap water preheating plate heat exchanger (5) and the water tank (4).

5. The cryogenic refrigeration waste heat recovery system of claim 4, wherein, The water tank (4) is further provided with a liquid level sensor (12) matched with the electric regulating valve (11).

6. The cryogenic refrigeration waste heat recovery system of claim 1, wherein, The refrigerant heat recovery device (7) and the heat pump unit (2) respectively recover the waste heat of the refrigerant gas and the waste heat of the spraying water of the evaporative condenser (10).

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