Large-temperature-difference heat supply network and water loop heat pump flexible heat supply system based on low-temperature industrial waste heat

Abstract

According to the large-temperature-difference heat supply network and water loop heat pump flexible heat supply system based on the low-temperature industrial waste heat, a low-grade combined clean heat source is composed of process waste heat, solar energy and geothermal energy and meets the heat supply requirements of heat consumers such as a conventional heat supply tail end and a water loop heat pump, heat supply transmission and distribution are conducted through a heat supply network according to the cascade efficient principle, the water supply temperature of the heat supply network is 40-50 DEG C, and the return water temperature is 4-7 DEG C; the ultra-large temperature difference heat supply network running and zero-carbon heat supply mode driven by a low-grade heat source is achieved, heat supply network supplied water of about 45 DEG C is firstly fed into a mixed tail end heat user, is cooled to 35-38 DEG C and then is fed into a floor heating heat user, is cooled to 30-33 DEG C and then is fed into a mixed tail end water loop heat pump user, and is cooled to 10-12 DEG C and then enters a floor heating water loop heat pump user. One part of the heat supply network return water cooled to 4-7 DEG C is returned to the ground source heat exchanger to be circularly heated, and the other part of the heat supply network return water is returned to the factory heat radiator to be heated to 35-40 DEG C, and is supplied out through the low-temperature large-temperature-difference energy storage tank after being subjected to heat compensation by solar energy.

Description

TECHNICAL FIELD

[0001] The patent relates to a large-temperature-difference heat network and a water ring heat pump flexible heating system based on low-temperature industrial waste heat, and belongs to the technical field of double-carbon clean heating. BACKGROUND

[0002] With the establishment of the national decision-making goals of carbon peak in 2030 and carbon neutralization in 2060, the future energy revolution in China will inevitably require a more substantial reduction in energy consumption, especially in fossil energy consumption. In this era, the heating field will inevitably require revolutionary technological innovation and engineering implementation. Making full use of various waste heat resources of high-energy-consuming industrial enterprises and natural energy such as solar energy and geothermal energy has become one of the main alternative forms for significantly reducing fossil energy heating.

[0003] In actual engineering practice, the above-mentioned low-grade clean energy has its limitations when used for heating. Among them, although industrial waste heat resources are very rich, their energy grade is often low, and most process waste heat is wasted through cooling circulating water systems, with an outlet water temperature of 30-40°C, which cannot be directly used for heating, but needs to be recovered through absorption heat pumps, compression heat pumps, etc., which requires a large amount of high-quality and high-cost energy such as driving steam or electricity.

[0004] Solar energy has a relatively low energy density, and the actual system conversion efficiency is low during winter heating operation, especially when there is sunlight only during the day. Therefore, there are few main solar heating systems, which can only be used as auxiliary heat sources.

[0005] The energy grade of shallow geothermal energy is too low (5-15°C), and it needs to rely on heat pumps for recovery to be used for heating.

[0006] At present, the supply water temperature of most primary networks is often high (60-120°C), and the return water temperature is mostly 40-55°C. This is the basic condition of the actual operation of traditional heating sources such as combined heat and power and boiler rooms and their heat network systems.

[0007] On the other hand, due to the limitations of the end type, public buildings or old residential buildings use radiators, fan coils, etc. that require higher temperature supply water temperatures, such as 45-60°C, and the return water temperature is often 35-45°C. However, the supply water temperature of new residential buildings is only 35-40°C, and the return water temperature is 25-35°C.

[0008] Another special indoor heating equipment system is a water ring heat pump system, that is, if there is a cheap low-temperature heat source (for example, 8-15 ℃ level) sent to each indoor heat user, and each household is provided with a small household water ring heat pump unit, the evaporator of which absorbs heat from the low-temperature heat source water, and through the heat pump cycle and the heat pump condenser, the heat is transferred to the indoor heating water, realizing efficient heat pump heating. The heating heat load of 100 square meters of energy-saving building is about 3-4 MW, and only about 1 kW of input power (equivalent to the power consumption of 1.5 air conditioners) is needed to meet the heating demand. However, this kind of heating method is rarely used in China, and there is a lack of practical application scenarios and cases, the investment is relatively high, and there is a lack of economic efficiency and practical heating operation operability, and the replicability is not strong. SUMMARY

[0009] The purpose and task of the present patent is to design a new low-temperature large-temperature-difference heat network heating system based on low-grade heat source and water ring heat pump technology, to realize the maximum utilization of process waste heat and natural energy for large-scale urban centralized heating, which is expected to help achieve the carbon neutralization target in the heating field.

[0010] The patent specifically describes a large-temperature-difference heat network and water ring heat pump flexible heating system based on low-temperature industrial waste heat, which comprises a low-grade combined clean heat source subsystem, a low-temperature large-temperature-difference heating terminal heat user group, and a low-temperature large-temperature-difference heat network water transmission and distribution subsystem. The low-grade combined clean heat source subsystem comprises heat exchange equipment and energy storage equipment of plant process waste heat, solar energy and geothermal energy. The low-temperature large-temperature-difference heating terminal heat user group comprises mixed terminal heat users 6, floor heating heat users 7, mixed terminal water ring heat pump users U1 and floor heating water ring heat pump users U2. The low-temperature large-temperature-difference heat network water transmission and distribution subsystem comprises a heat network water supply and return double-line dry pipe, a mixed and parallel cascade transmission and distribution pipe system combined with subarea series connection but parallel connection of heat users in the same type area. The plant process waste heat is used as the main heat source, and a plant heat radiator 1 is arranged for emitting the process waste heat. The cooling water inlet of the plant heat radiator 1 is connected with the water outlet of a process cooling pump P1. The water inlets of the process cooling pump P1 are respectively connected with the water outlets of V2 and V3 electric valves. The water inlet of the V2 electric valve is connected with the outlet of a cooling tower 4. The cooling water outlet of the plant heat radiator 1 is connected with the water inlets of the V5 electric valve and a solar energy collector 2 in addition to being connected with the water inlet of the cooling tower 4 through the V1 electric valve. The water outlet of the solar energy collector 2 is connected with the water inlet of a V6 electric valve. The cooling water outlet of the plant heat radiator 1 is also connected with the water outlet of the V6 electric valve through a V4 electric valve. The mixed water pipelines of the V6 electric valve are respectively connected with the water inlets of V8 and V7 electric valves and the water inlet of a low-temperature large-temperature-difference energy storage tank 5. The water outlet of the low-temperature large-temperature-difference energy storage tank 5 is connected with the water inlet of an energy storage booster pump P2. The water outlets of the energy storage booster pump P2 are respectively connected with the water inlets of V10 and V9 electric valves and the water outlet of the V8 electric valve. The water outlet of the V8 electric valve is also connected with the heating water inlet of the mixed terminal heat users 6. The heating water outlets of the mixed terminal heat users 6 are respectively connected with the water outlets of V10, V11 and V12 electric valves.The outlet of the V12 electric valve is connected with the inlet of the floor heating water user 7, the outlet of the floor heating water user 7 is connected with the outlet of the V11 electric valve, the inlet of the V14 electric valve and the inlet of the V15 electric valve through the V13 electric valve, the outlet of the V15 electric valve is respectively connected with the inlet of the V16 electric valve and the inlet of the V17 electric valve of the mixed terminal water loop heat pump user U1, the mixed terminal water loop heat pump user U1 is further provided with the high-temperature heat source type water loop heat pump 8, the first user heating pump 85, the mixed terminal heat exchanger 86 and the V18 electric valve, wherein the high-temperature heat source type water loop heat pump 8 comprises a high-temperature type evaporator 81, a high-temperature type compressor 82, a high-temperature type condenser 83, a high-temperature type expansion valve 84 and connecting pipeline components thereof, wherein the inlet of the high-temperature type evaporator 81 is connected with the outlet of the V17 electric valve, the outlet of the high-temperature type evaporator 81 is connected with the inlet of the V18 electric valve, the outlet of the high-temperature type condenser 83 is connected with the inlet of the mixed terminal heat exchanger 86 through the first user heating pump 85, and the inlet of the high-temperature type condenser 83 is connected with the outlet of the mixed terminal heat exchanger 86; the outlet of the V18 electric valve is respectively connected with the outlet of the V16 electric valve, the outlet of the V23 electric valve, the inlet of the V19 electric valve and the inlet of the V20 electric valve of the floor heating water loop heat pump user U2, the floor heating water loop heat pump user U2 is further provided with the low-temperature heat source type water loop heat pump 9, the second user heating pump 95, the floor heating heat exchanger 96 and the V21 electric valve, wherein the low-temperature heat source type water loop heat pump 9 comprises a low-temperature type evaporator 91, a low-temperature type compressor 92, a low-temperature type condenser 93, a low-temperature type expansion valve 94 and connecting pipeline components thereof, wherein the inlet of the low-temperature type evaporator 91 is connected with the outlet of the V20 electric valve, the outlet of the low-temperature type evaporator 91 is connected with the inlet of the V21 electric valve, the outlet of the low-temperature type condenser 93 is connected with the inlet of the floor heating heat exchanger 96 through the second user heating pump 95, and the inlet of the low-temperature type condenser 93 is connected with the outlet of the floor heating heat exchanger 96; the outlet of the V21 electric valve is respectively connected with the outlet of the V19 electric valve, the inlet of the V22 electric valve, the inlet of the V3 electric valve and the outlet of the V14 electric valve; the outlet of the V22 electric valve is connected with the inlet of the ground source heat exchanger 3, the outlet of the ground source heat exchanger 3 is respectively connected with the inlet of the V23 electric valve and the inlet of the V24 electric valve through the ground source circulating pump P3, and the outlet of the V24 electric valve is connected with the outlet of the factory heat radiator 1.

[0011] The mixed terminal heat user 6 includes several heat user groups in the form of radiator, fan-coil or floor heating terminal, and the connection relationship between each heat user is parallel, that is, the heat user groups of the mixed terminal heat user 6 share one heating water supply branch pipe and one heating water return branch pipe; the floor heating heat user 7 includes several heat user groups in the form of floor heating terminal, and the connection relationship between each heat user is parallel, that is, the heat user groups of the floor heating heat user 7 share one heating water supply branch pipe and one heating water return branch pipe; the mixed terminal water ring heat pump user U1 includes several heat user groups in the form of radiator, fan-coil or floor heating terminal, and each heat user is provided with an independent high-temperature heat source type water ring heat pump heating system, and the connection relationship between each heat user is parallel, that is, the heat user groups of the mixed terminal water ring heat pump user U1 share one low-temperature waste heat water supply branch pipe and one low-temperature waste heat water return branch pipe; the floor heating water ring heat pump user U2 includes several heat user groups in the form of floor heating terminal, and each heat user is provided with an independent low-temperature heat source type water ring heat pump heating system, and the connection relationship between each heat user is parallel, that is, the heat user groups of the floor heating water ring heat pump user U2 share one low-temperature waste heat water supply branch pipe and one low-temperature waste heat water return branch pipe.

[0012] The pipe end of the heating water supply branch pipe shared by the heat user groups of the mixed terminal heat user 6 is truncated, and the total outlet of the heating water return branch pipe shared by the heat user groups is connected with the total inlet of the heating water supply branch pipe shared by the heat user groups of the floor heating heat user 7, that is, the heat network water of the mixed terminal heat user 6 and the floor heating heat user 7 constitutes a series relationship as a whole; the pipe end of the heating water supply branch pipe shared by the heat user groups of the floor heating heat user 7 is truncated, and the total outlet of the heating water return branch pipe shared by the heat user groups is connected with the total inlet of the low-temperature waste heat water supply branch pipe shared by the heat user groups of the mixed terminal water ring heat pump user U1, that is, the heat network water of the floor heating heat user 7 and the low-temperature heat source water of the mixed terminal water ring heat pump user U1 constitute a series relationship as a whole; the pipe end of the low-temperature heat source water supply branch pipe shared by the heat user groups of the mixed terminal water ring heat pump user U1 is truncated, and the total outlet of the low-temperature heat source water return branch pipe shared by the heat user groups is connected with the total inlet of the low-temperature waste heat water supply branch pipe shared by the heat user groups of the floor heating water ring heat pump user U2, that is, the low-temperature heat source water of the mixed terminal water ring heat pump user U1 and the low-temperature heat source water of the floor heating water ring heat pump user U2 constitute a series relationship as a whole.

[0013] The ground source heat exchanger 3 comprises several distributed shallow geothermal energy heat exchangers in the form of ground heat exchanger, underground water well group or large flow surface water and seawater; the low-temperature heat source water inlet pipe and outlet pipe of the ground source heat exchanger 3 are communicated with the low-temperature heat source water outlet pipe and inlet pipe of the floor heating water ring heat pump user U2 in the heating period, and are communicated with the cooling circulating water outlet pipe and inlet pipe of the factory heat radiator 1 in the non-heating period.

[0014] The factory heat radiator 1 comprises one or several process heat radiators in high-energy-consumption factories, which can be located in one or several factories.

[0015] The solar heat collector 2 comprises one or several groups of solar heat collectors, which can be arranged in a centralized or decentralized manner when several groups are arranged.

[0016] The supply water main pipe temperature of the low-temperature large-temperature-difference heat network water transmission and distribution subsystem is 40-50°C, and the return water main pipe temperature is 4-7°C, wherein the heating water supply branch main pipe temperature of the mixed end heat user 6 is 40-50°C, the heating water supply branch main pipe temperature of the floor heating heat user 7 is 35-38°C, the low-temperature heat source water supply branch main pipe temperature of the mixed end water ring heat pump user U1 is 30-33°C, the low-temperature heat source water supply branch main pipe temperature of the floor heating water ring heat pump user U2 is 10-12°C, the low-temperature heat source water return branch main pipe temperature of the floor heating water ring heat pump user U2 is 4-7°C, the low-temperature heat source water outlet pipe temperature of the ground source heat exchanger 3 is 7-15°C, the cooling water outlet temperature of the factory heat radiator 1 is 35-40°C, and the outlet water temperature of the solar heat collector 2 is 40-50°C.

[0017] The innovation and technical effects of the patent are as follows.

[0018] The patent can realize that the centralized heating load is completely borne by zero-carbon low-grade energy resources such as industrial waste heat, solar energy and geothermal energy, and can realize gradient heating, gradient transmission and distribution and gradient heat release heating according to the energy resources and the energy grade demand of the heat user side, without consuming a large amount of fossil energy for heating, and truly realizing a large-scale carbon neutral clean heating mode.

[0019] The heat user side adopts different heat supply terminal types, including conventional mixed terminal type, floor heating, and more importantly, by adopting high and low temperature two-stage water ring heat pump, the heat of circulating water of heat supply network is utilized in stages and depth, and the return water temperature is finally reduced to the ultra-low temperature level of 4-7°C, so that the low temperature heat supply network with large temperature difference is realized for the first time in the centralized heating industry. For example, if the supply water temperature is 120°C and the return water temperature is 70°C, the maximum temperature difference of the heat supply network is about 50°C, which is equivalent to the traditional high temperature heat supply network. For example, the design supply water temperature is 120 / 70°C, the temperature difference is 50°C, the actual operation of most supply water temperature is 90-110°C, the return water temperature is 40-55°C, and the actual supply and return water temperature difference is about 35-50°C. The supply and return water temperature difference of many county-level medium and low heat supply networks is only about 15-25°C; and the supply water temperature of a few low temperature water large flow heating systems is as low as 50-60°C, the return water temperature is about 38-42°C, and the temperature difference is only about 15°C. Therefore, in the case of supply water temperature of 40-50°C and supply and return water temperature difference of 36-46°C, the present patent is a unique and original technology, which creates the best technical conditions for large-scale use of process waste heat and other low-grade heat sources as the main heat source of urban centralized heating, and can greatly reduce the circulating water flow, pump power consumption and operation cost.

[0020] The water ring heat pump adopts high temperature heat source type and low temperature heat source type, and the former is preferentially used for high energy consumption buildings and heating terminal types such as radiators and fan coils that require higher supply water temperature, and the latter is mainly used for floor heating that requires lower supply water temperature, so that the temperature matching of the evaporator side and the condenser side of the two heat pumps is better, the heat pump heating efficiency is greatly improved, the heat pump and compressor capacity is significantly lower, and the power consumption and operation cost is very low.

[0021] The heat supply network return water temperature is very low, which can greatly improve the cooling conditions of process production equipment, improve production efficiency, improve the energy utilization rate of the whole factory, and achieve significant energy saving and carbon reduction benefits.

[0022] The heat supply network transmission and distribution system realizes series and parallel combination, realizes the best matching of the heat source supply side and the demand side, flexibly adjusts the heat supply of each heat user and the best heat extraction order of the heat source side, realizes better flexibility adjustment of the heat supply system, realizes flexible heat supply of the whole system, and further improves the system energy efficiency ratio and economy.

[0023] The method for behavior energy-saving heating driven by economic benefits: a large-temperature-difference heat network based on low-temperature industrial waste heat and a water ring heat pump flexible heating system are adopted, the low-grade combined clean heat source subsystem, the low-temperature large-temperature-difference heat network water transmission and distribution subsystem and the water ring heat pump body are borne by the heat company, the construction cost is usually basically equivalent to or slightly higher than the statutory heat source / heat network / courtyard pipe network matching fee, the excess part of the investment can be recovered through heating service charges, and the heat supply company only needs to bear the low-temperature heat source water circulating pump power consumption of the water ring heat pump, the power consumption of the indoor water ring heat pump host and the heating system is borne by the final heat user, the heat user controls independently, carries out room-by-room heating, time-by-time heating and greatly reduces the heating energy consumption and the power consumption, greatly reduces the low-temperature heat source water heat load and the heat source heat demand of the whole heating area, and greatly reduces the energy consumption of the central heating system as a whole.

[0024] Therefore, the present patent fundamentally changes the form of traditional heating system relying on fossil fuel heating and conventional heat pump heating and its energy consumption, realizes low-grade heat source for large-temperature-difference heat network efficient central heating, has obvious energy-saving, healthy, environmental protection and economic advantages, is convenient for large-scale popularization and application, embodies the actual development needs and energy-saving and environmental protection era theme under the condition of carbon neutralization. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a system schematic diagram of the present patent.

[0026] Figure 1 The numbers and names of the components in the figure are as follows: factory heat radiator 1, solar heat collector 2, ground source heat exchanger 3, cooling tower 4, low-temperature large-temperature-difference energy storage tank 5, mixed terminal heat user 6, floor heating heat user 7, high-temperature heat source type water ring heat pump 8, high-temperature type evaporator 81, high-temperature type compressor 82, high-temperature type condenser 83, high-temperature type expansion valve 84, first user heating pump 85, mixed terminal heat exchanger 86, low-temperature heat source type water ring heat pump 9, low-temperature type evaporator 91, low-temperature type compressor 92, low-temperature type condenser 93, low-temperature type expansion valve 94, second user heating pump 95, floor heating heat exchanger 96, process cooling pump P1, energy storage booster pump P2, ground source circulating pump P3, mixed terminal water ring heat pump user U1, floor heating water ring heat pump user U2. DETAILED DESCRIPTION

[0027] Figure 1 It is a system schematic diagram of the present patent.

[0028] The patent specifically describes a large-temperature-difference heat network and water ring heat pump flexible heating system based on low-temperature industrial waste heat, which comprises a low-grade combined clean heat source subsystem, a low-temperature large-temperature-difference heating terminal heat user group, and a low-temperature large-temperature-difference heat network water transmission and distribution subsystem. The low-grade combined clean heat source subsystem comprises heat exchange equipment and energy storage equipment of plant process waste heat, solar energy and geothermal energy. The low-temperature large-temperature-difference heating terminal heat user group comprises mixed terminal heat users 6, floor heating heat users 7, mixed terminal water ring heat pump users U1 and floor heating water ring heat pump users U2. The low-temperature large-temperature-difference heat network water transmission and distribution subsystem comprises a heat network water supply and return double-line dry pipe, a mixed and parallel cascade transmission and distribution pipe system combined with subarea series connection but parallel connection of heat users in the same type area. The plant process waste heat is used as the main heat source, and a plant heat radiator 1 is arranged for emitting the process waste heat. The cooling water inlet of the plant heat radiator 1 is connected with the water outlet of a process cooling pump P1. The water inlets of the process cooling pump P1 are respectively connected with the water outlets of V2 and V3 electric valves. The water inlet of the V2 electric valve is connected with the outlet of a cooling tower 4. The cooling water outlet of the plant heat radiator 1 is connected with the water inlets of the V5 electric valve and a solar energy collector 2 in addition to being connected with the water inlet of the cooling tower 4 through the V1 electric valve. The water outlet of the solar energy collector 2 is connected with the water inlet of a V6 electric valve. The cooling water outlet of the plant heat radiator 1 is also connected with the water outlet of the V6 electric valve through a V4 electric valve. The mixed water pipelines of the V6 electric valve are respectively connected with the water inlets of V8 and V7 electric valves and the water inlet of a low-temperature large-temperature-difference energy storage tank 5. The water outlet of the low-temperature large-temperature-difference energy storage tank 5 is connected with the water inlet of an energy storage booster pump P2. The water outlets of the energy storage booster pump P2 are respectively connected with the water inlets of V10 and V9 electric valves and the water outlet of the V8 electric valve. The water outlet of the V8 electric valve is also connected with the heating water inlet of the mixed terminal heat users 6. The heating water outlets of the mixed terminal heat users 6 are respectively connected with the water outlets of V10, V11 and V12 electric valves.The outlet of the V12 electric valve is connected with the heating water inlet of the floor heating heat user 7, the heating water outlet of the floor heating heat user 7 is connected with the outlet of the V11 electric valve, the inlet of the V14 electric valve and the inlet of the V15 electric valve through the V13 electric valve, the outlet of the V15 electric valve is respectively connected with the inlet of the V16 electric valve and the inlet of the V17 electric valve of the mixed terminal water loop heat pump user U1, the mixed terminal water loop heat pump user U1 is further provided with the high-temperature heat source type water loop heat pump 8, the first user heating pump 85, the mixed terminal heat exchanger 86 and the V18 electric valve, wherein the high-temperature heat source type water loop heat pump 8 comprises a high-temperature type evaporator 81, a high-temperature type compressor 82, a high-temperature type condenser 83, a high-temperature type expansion valve 84 and connecting pipeline components thereof, wherein the inlet of the high-temperature type evaporator 81 is connected with the outlet of the V17 electric valve, the outlet of the high-temperature type evaporator 81 is connected with the inlet of the V18 electric valve, the outlet of the high-temperature type condenser 83 is connected with the heating water inlet of the mixed terminal heat exchanger 86 through the first user heating pump 85, and the inlet of the high-temperature type condenser 83 is connected with the heating water outlet of the mixed terminal heat exchanger 86; the outlet of the V18 electric valve is respectively connected with the outlet of the V16 electric valve, the outlet of the V23 electric valve, the inlet of the V19 electric valve and the inlet of the V20 electric valve of the floor heating water loop heat pump user U2, the floor heating water loop heat pump user U2 is further provided with the low-temperature heat source type water loop heat pump 9, the second user heating pump 95, the floor heating heat exchanger 96 and the V21 electric valve, wherein the low-temperature heat source type water loop heat pump 9 comprises a low-temperature type evaporator 91, a low-temperature type compressor 92, a low-temperature type condenser 93, a low-temperature type expansion valve 94 and connecting pipeline components thereof, wherein the inlet of the low-temperature type evaporator 91 is connected with the outlet of the V20 electric valve, the outlet of the low-temperature type evaporator 91 is connected with the inlet of the V21 electric valve, the outlet of the low-temperature type condenser 93 is connected with the heating water inlet of the floor heating heat exchanger 96 through the second user heating pump 95, and the inlet of the low-temperature type condenser 93 is connected with the heating water outlet of the floor heating heat exchanger 96; the outlet of the V21 electric valve is respectively connected with the outlet of the V19 electric valve, the inlet of the V22 electric valve, the inlet of the V3 electric valve and the outlet of the V14 electric valve; the outlet of the V22 electric valve is connected with the inlet of the ground source heat exchanger 3, the outlet of the ground source heat exchanger 3 is respectively connected with the inlet of the V23 electric valve and the inlet of the V24 electric valve through the ground source circulating pump P3, and the outlet of the V24 electric valve is connected with the outlet of the factory heat radiator 1.

[0029] The mixed terminal heat user 6 includes several heat user groups in the form of radiator, fan-coil or floor heating terminal, and the connection relationship between each heat user is parallel, that is, the heat user groups of the mixed terminal heat user 6 share one heating water supply branch pipe and one heating water return branch pipe; the floor heating heat user 7 includes several heat user groups in the form of floor heating terminal, and the connection relationship between each heat user is parallel, that is, the heat user groups of the floor heating heat user 7 share one heating water supply branch pipe and one heating water return branch pipe; the mixed terminal water ring heat pump user U1 includes several heat user groups in the form of radiator, fan-coil or floor heating terminal, and each heat user is provided with an independent high-temperature heat source type water ring heat pump heating system, and the connection relationship between each heat user is parallel, that is, the heat user groups of the mixed terminal water ring heat pump user U1 share one low-temperature waste heat water supply branch pipe and one low-temperature waste heat water return branch pipe; the floor heating water ring heat pump user U2 includes several heat user groups in the form of floor heating terminal, and each heat user is provided with an independent low-temperature heat source type water ring heat pump heating system, and the connection relationship between each heat user is parallel, that is, the heat user groups of the floor heating water ring heat pump user U2 share one low-temperature waste heat water supply branch pipe and one low-temperature waste heat water return branch pipe.

[0030] The pipe end of the heating water supply branch pipe shared by the heat user groups of the mixed terminal heat user 6 is truncated, and the total outlet of the heating water return branch pipe shared by the heat user groups is connected with the total inlet of the heating water supply branch pipe shared by the heat user groups of the floor heating heat user 7, that is, the heat network water of the mixed terminal heat user 6 and the floor heating heat user 7 constitutes a series relationship as a whole; the pipe end of the heating water supply branch pipe shared by the heat user groups of the floor heating heat user 7 is truncated, and the total outlet of the heating water return branch pipe shared by the heat user groups is connected with the total inlet of the low-temperature waste heat water supply branch pipe shared by the heat user groups of the mixed terminal water ring heat pump user U1, that is, the heat network water of the floor heating heat user 7 and the low-temperature heat source water of the mixed terminal water ring heat pump user U1 constitute a series relationship as a whole; the pipe end of the low-temperature heat source water supply branch pipe shared by the heat user groups of the mixed terminal water ring heat pump user U1 is truncated, and the total outlet of the low-temperature heat source water return branch pipe shared by the heat user groups is connected with the total inlet of the low-temperature waste heat water supply branch pipe shared by the heat user groups of the floor heating water ring heat pump user U2, that is, the low-temperature heat source water of the mixed terminal water ring heat pump user U1 and the low-temperature heat source water of the floor heating water ring heat pump user U2 constitute a series relationship as a whole.

[0031] The ground source heat exchanger 3 comprises several distributed shallow geothermal energy heat exchangers in the form of ground heat exchanger, underground water well group or large flow surface water and sea water; the low-temperature heat source water inlet pipe and outlet pipe of the ground source heat exchanger are communicated with the low-temperature heat source water outlet pipe and inlet pipe of the floor heating water ring heat pump user U2 in the heating period, and are communicated with the cooling circulating water outlet pipe and inlet pipe of the factory heat radiator 1 in the non-heating period.

[0032] The factory heat radiator 1 comprises one or several process heat radiators in high-energy-consumption factories, which can be located in one or several factories.

[0033] The solar heat collector 2 comprises one or several groups of solar heat collectors, which can be arranged in a centralized or decentralized manner when several groups are arranged.

[0034] The supply water main pipe temperature of the low-temperature large-temperature-difference heat network water transmission and distribution subsystem is 40-50°C, and the return water main pipe temperature is 4-7°C; the floor heating water supply branch main pipe temperature of the mixed end heat user 6 is 40-50°C, the floor heating water supply branch main pipe temperature of the floor heating heat user 7 is 35-38°C, the low-temperature heat source water supply branch main pipe temperature of the mixed end water ring heat pump user U1 is 30-33°C, the low-temperature heat source water supply branch main pipe temperature of the floor heating water ring heat pump user U2 is 10-12°C, the low-temperature heat source water return branch main pipe temperature of the floor heating water ring heat pump user U2 is 4-7°C; the low-temperature heat source water outlet pipe temperature of the ground source heat exchanger 3 is 7-15°C, the cooling water outlet temperature of the factory heat radiator 1 is 35-40°C, and the outlet water temperature of the solar heat collector 2 is 40-50°C.

[0035] It should be noted that the specific application mode of the present patent is not limited to the specific description of the above embodiments, and any simple modification and application made on the basis of the above embodiments, such as not setting the solar heater or the ground source heat exchanger, not distinguishing the mixed end and the floor heating end type of the heat user, not distinguishing the high-temperature waste heat water type and the low-temperature waste heat water type of the water ring heat pump, and simple modification of the heat source equipment, energy storage tank, heat user and connecting pipeline, etc., can be considered as falling within the protection scope of the present patent.

Claims

1. A flexible heating system based on a large temperature difference heat network and water-loop heat pump using low-temperature industrial waste heat, comprising three parts: a low-grade combined clean heat source subsystem, a low-temperature large temperature difference heating terminal user group, and a low-temperature large temperature difference heat network water transmission and distribution subsystem, characterized in that... The low-grade combined clean heat source subsystem includes heat exchange equipment and energy storage equipment for waste heat from factory processes, solar energy and geothermal energy. The low-temperature large temperature difference heating terminal user group includes mixed terminal users (6), floor heating users (7), mixed terminal water loop heat pump users (U1) and floor heating water loop heat pump users (U2). The low-temperature large temperature difference heat network water transmission and distribution subsystem includes dual-line main pipes for heat network supply and return water, and a mixed-connected cascade transmission and distribution pipeline system that combines zoned series connection but parallel connection of heat users in the same area. The waste heat from the factory process serves as the main heat source, and a factory heat exchanger (1) is installed to dissipate the waste heat. The cooling water inlet of the factory heat exchanger (1) is connected to the outlet of the process cooling pump (P1). The inlet of the process cooling pump (P1) is connected to the outlet of the V2 electric valve and the outlet of the V3 electric valve. The inlet of the V2 electric valve is connected to the outlet of the cooling tower (4). In addition to being connected to the inlet of the cooling tower (4) via the V1 electric valve, the cooling water outlet of the factory heat exchanger (1) is also connected to the inlet of the solar collector (2) via the V5 electric valve. The outlet of the solar collector (2) is connected to the inlet of the V6 electric valve. The cooling water outlet of the valve is also connected to the outlet of the electric valve V6 via the electric valve V4. The mixed water pipeline is connected to the inlet of the electric valve V8 and to the inlet of the low-temperature large temperature difference energy storage tank (5) via the electric valve V7. The outlet of the low-temperature large temperature difference energy storage tank (5) is connected to the inlet of the energy storage booster pump (P2). The outlet of the energy storage booster pump (P2) is connected to the inlet of the electric valve V10 and to the outlet of the electric valve V8 via the electric valve V9. The outlet of the electric valve V8 is also connected to the heating water inlet of the mixed terminal heat user (6). The heating water outlet of the mixed terminal heat user (6) is connected to the outlet of the electric valve V10 and to the outlet of the electric valve V11. The inlet of the electric valve is connected to the inlet of the V12 electric valve; the outlet of the V12 electric valve is connected to the heating water inlet of the floor heating user (7); the heating water outlet of the floor heating user (7) is connected to the outlet of the V11 electric valve, the inlet of the V14 electric valve, and the inlet of the V15 electric valve via the V13 electric valve; the outlet of the V15 electric valve is connected to the inlet of the V16 electric valve and the inlet of the V17 electric valve of the mixed terminal water loop heat pump user (U1); the mixed terminal water loop heat pump user (U1) is also equipped with a high-temperature heat source type water loop heat pump (8), a first user heating pump (85), and a mixed terminal heat exchanger. Heater (86), V18 electric valve, wherein the high temperature heat source type water ring heat pump (8) includes a high temperature type evaporator (81), a high temperature type compressor (82), a high temperature type condenser (83), a high temperature type expansion valve (84) and its connecting pipe components, wherein the inlet of the high temperature type evaporator (81) is connected to the outlet of the V17 electric valve, the outlet of the high temperature type evaporator (81) is connected to the inlet of the V18 electric valve, the outlet of the high temperature type condenser (83) is connected to the heating water inlet of the mixing terminal heat exchanger (86) through the first user heating pump (85), and the inlet of the high temperature type condenser (83) is connected to the heating water outlet of the mixing terminal heat exchanger (86);The outlet of the V18 electric valve is connected to the outlet of the V16 electric valve, the outlet of the V23 electric valve, the inlet of the V19 electric valve, and the inlet of the V20 electric valve of the floor heating water loop heat pump user (U2). The floor heating water loop heat pump user (U2) is also equipped with a low-temperature heat source type water loop heat pump (9), a second user heating pump (95), a floor heating heat exchanger (96), and a V21 electric valve. The low-temperature heat source type water loop heat pump (9) includes a low-temperature evaporator (91), a low-temperature compressor (92), a low-temperature condenser (93), a low-temperature expansion valve (94), and its connecting pipe components. The inlet of the low-temperature evaporator (91) is connected to the outlet of the V20 electric valve, and the outlet of the low-temperature evaporator (91) is connected to the V21 electric valve. The valve inlet is connected, the outlet of the low-temperature condenser (93) is connected to the heating water inlet of the floor heating heat exchanger (96) through the second user heating pump (95), and the inlet of the low-temperature condenser (93) is connected to the heating water outlet of the floor heating heat exchanger (96); the outlet of the V21 electric valve is connected to the outlet of the V19 electric valve, the inlet of the V22 electric valve, the inlet of the V3 electric valve, and the outlet of the V14 electric valve; the outlet of the V22 electric valve is connected to the inlet of the ground source heat exchanger (3), and the outlet of the ground source heat exchanger (3) is connected to the inlet of the V23 electric valve and the inlet of the V24 electric valve through the ground source circulation pump (P3), and the outlet of the V24 electric valve is connected to the outlet of the factory heat exchanger (1).

2. The flexible heating system based on low-temperature industrial waste heat, large temperature difference heat network, and water loop heat pump as described in claim 1, is characterized in that... The mixed-terminal heat users (6) include several groups of heat users using radiators, fan coil units, or floor heating terminals. The heating water branch connections between each heat user are in parallel, meaning that the heat user groups of the mixed-terminal heat users (6) share a heating water supply branch pipe and a return branch pipe. The floor heating heat users (7) include several groups of heat users using floor heating terminals. The heating water branch connections between each heat user are in parallel, meaning that the heat user groups of the floor heating heat users (7) share a heating water supply branch pipe and a return branch pipe. The mixed-terminal water loop heat pump users (U1) include several groups of heat users using radiators, fan coil units, or floor heating terminals. The mixed-terminal water-loop heat pump user group (U1) consists of several user groups using the floor heating terminal form. Each user is equipped with an independent high-temperature heat source water-loop heat pump heating system, and the low-temperature waste hot water branch connections between each user are in parallel. That is, the mixed-terminal water-loop heat pump user group (U2) shares a low-temperature waste hot water supply branch pipe and return branch pipe.

3. The flexible heating system based on low-temperature industrial waste heat with a large temperature difference heat network and water loop heat pump as described in claim 2, characterized in that... The heating water supply branch pipe shared by the mixed terminal heat users (6) is cut off at the end, and the total outlet of the shared heating water return branch pipe is connected to the total inlet of the heating water supply branch pipe shared by the floor heating heat users (7). That is, the heating network water of the mixed terminal heat users (6) and the floor heating heat users (7) are connected in series. The heating water supply branch pipe shared by the floor heating heat users (7) is cut off at the end, and the total outlet of the shared heating water return branch pipe is connected to the low-temperature waste hot water shared by the mixed terminal water loop heat pump users (U1). The main inlet of the water supply branch pipe is connected, that is, the heat network water of the floor heating user (7) and the low temperature heat source water of the mixed terminal water loop heat pump user (U1) are connected in series. The end of the low temperature heat source water supply branch pipe shared by the heat user group of the mixed terminal water loop heat pump user (U1) is cut off, and the main outlet of the shared low temperature heat source water return branch pipe is connected to the main inlet of the low temperature waste hot water supply branch pipe shared by the heat user group of the floor heating water loop heat pump user (U2). That is, the low temperature heat source water of the mixed terminal water loop heat pump user (U1) and the low temperature heat source water of the floor heating water loop heat pump user (U2) are connected in series.

4. The flexible heating system based on low-temperature industrial waste heat with a large temperature difference heat network and a water loop heat pump as described in claim 1, characterized in that... The ground source heat exchanger (3) includes several distributed shallow geothermal heat exchangers, which adopt the buried pipe heat exchanger type, the groundwater well group type, or the large flow surface water and seawater type; its low temperature heat source water inlet pipe and outlet pipe are connected to the low temperature heat source water outlet pipe and inlet pipe of the floor heating water loop heat pump user (U2) respectively during the heating season, and are connected to the cooling circulating water outlet pipe and inlet pipe of the factory heat exchanger (1) during the non-heating season.

5. The flexible heating system based on low-temperature industrial waste heat with a large temperature difference heat network and a water loop heat pump as described in claim 1, characterized in that... The plant heat exchanger (1) includes one or more process heat exchangers in a high-energy-consuming plant, which may be located in one or more plants.

6. The flexible heating system based on low-temperature industrial waste heat, large temperature difference heat network, and water loop heat pump as described in claim 1, is characterized in that... The solar collector (2) includes one or more sets of solar collectors. When several sets are set, their geographical locations can be arranged in a centralized or decentralized manner.

7. The flexible heating system based on low-temperature industrial waste heat with a large temperature difference heat network and a water loop heat pump as described in claim 1, characterized in that... The temperature of the water supply main pipe of the low-temperature large temperature difference heat network water transmission and distribution subsystem is 40-50℃, and the temperature of the return water main pipe is 4-7℃. Among them, the temperature of the heating water supply branch pipe of the mixed terminal heat user (6) is 40-50℃, the temperature of the heating water supply branch pipe of the floor heating heat user (7) is 35-38℃, the temperature of the low-temperature heat source water supply branch pipe of the mixed terminal water loop heat pump user (U1) is 30-33℃, the temperature of the low-temperature heat source water supply branch pipe of the floor heating water loop heat pump user (U2) is 10-12℃, and the temperature of the low-temperature heat source water return branch pipe of the floor heating water loop heat pump user (U2) is 4-7℃; the temperature of the low-temperature heat source water outlet pipe of the ground source heat exchanger (3) is 7-15℃, the temperature of the cooling water outlet of the factory heat exchanger (1) is 35-40℃, and the temperature of the outlet of the solar collector (2) is 40-50℃.

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