CN107131546A - Hot-water type solar and superficial layer geothermal energy cogeneration of heat and power integral system and operation method - Google Patents

Abstract

The invention discloses a hot water type solar shallow geothermal energy combined heat and power integrated system, including four main parts: a solar hot water system, a ground source heat pump low temperature power generation integrated system, a heating water system and a domestic hot water supply system. Among them, the solar hot water system is composed of a water storage tank, the first water pump, and a solar collector; the ground source heat pump low-temperature power generation integrated system is composed of a compression-expansion dual-function machine head, a permanent magnet electric power generation integrated motor, and high and low side heat exchangers. , expansion valve, working fluid pump, two one-way valves, the second water pump, and the underground low-level heat source heat sink system; the heating water system is composed of heating water supply and return pipelines, water storage tanks, and building heating systems; domestic hot water supply The system consists of tap water pipelines, domestic hot water supply pipelines, water storage tanks and building hot water supply systems. By adjusting the conduction or closing of the valve, the solar ground source heat pump is used for heating and hot water during the heating period, and the solar energy is used for power generation and hot water supply during the non-heating period.

Description

Hot water type solar shallow geothermal energy combined heat and power integrated system and operation method

technical field

The invention belongs to the technical field of utilization of solar shallow geothermal energy, and in particular relates to a hot water type solar shallow geothermal energy combined heat and power integrated system and an operation method.

Background technique

In recent years, with the continuous development of urbanization and the continuous improvement of people's requirements for the comfort of living and working environments, the construction industry has ushered in the rapid growth, and building energy consumption has shown a continuous upward trend. The proportion of my country's building energy consumption in the final energy consumption of the whole society has risen from 10% in the late 1970s to about 30%. Among them, heating in winter in the northern region is the main part of building energy consumption, consuming more than 150 million tons of standard coal per year. At present, heating is still mainly based on the consumption of fossil fuels, causing a large amount of greenhouse gases and various harmful substances to be emitted, and the ecological environment is constantly threatened. Raw coal is scattered and burned in rural areas, causing widespread air pollution. Therefore, using clean energy as much as possible and accelerating the increase in the proportion of clean heating has become a new focus of national energy work.

Solar energy is inexhaustible and inexhaustible without mining and transportation. It is an important part of the development and utilization of new and renewable energy and has a huge market prospect. China's solar energy resources are very rich, two-thirds of the area's total annual radiation is greater than 5020MJ/m ² , and the annual sunshine hours are above 2200h, which has good conditions for effective development and utilization. The thermal utilization of low-temperature solar energy is the most direct solution, and it develops the fastest. People pay more and more attention to solar water heaters and heating technologies. my country's main heating area is in the north, which happens to be an area rich in solar energy resources. Especially in the heating season, there are many sunny days, which provide basic conditions for solar heating. Solar heating refers to the use of solar energy as the heat source of the heating system, and the use of solar collectors to convert solar energy into heat energy to provide heating for buildings in winter. Compared with pure solar hot water supply, my country's solar heating technology and engineering application level is relatively low. Most of them give priority to the development of passive solar heating, while the development of active solar heating systems in my country has been relatively slow, and its engineering application is still in its infancy. This is mainly due to the low energy flow density of solar energy, limited sunshine time, susceptible to climate influence, and energy imbalance in winter and summer, resulting in low operating temperature of traditional solar heating systems, large installation area of collectors, and the need to add auxiliary heat sources, energy storage Difficulties and problems such as excess heat in non-heating periods directly or indirectly affect the economy and reliability of its operation.

In addition, the ground source heat pump developed in recent years, as a HVAC technology using renewable energy, has opened up a new way for electric heating. The so-called ground source heat pump refers to a heating and air conditioning system composed of a water source heat pump unit, a geothermal energy exchange system, and a building system that uses rock and soil, groundwater, or surface water as a low-temperature heat source. Ground source heat pumps can be used for multiple purposes, with a wide range of applications, high operating efficiency, low maintenance costs, and significant environmental benefits. The application of the system has entered a stage of explosive rapid development. As of 2013, the number of demonstration projects announced by the Ministry of Housing and Urban-Rural Development has reached 324, most of which are heat supply in the north. Various types of buildings and heat pumps are used, but most of them are used in the suburbs of cities and few in rural areas. The independent operation of the ground source heat pump has two important disadvantages of unbalanced cold and heat and high initial investment. The application of ground source heat pumps must follow the principle of adapting measures to local conditions. For areas with uneven cooling and heating loads throughout the year, economic and technical analysis is required to determine whether to add auxiliary heat sources or cold sources so that the two can be reasonably matched to ensure the overall Efficient and economical operation of the system. To avoid the uneven heating and cooling load, the ground source heat pump emits and absorbs heat to the ground. Long-term operation causes the underground environment to deviate from the original equilibrium state, forming a cold and heat island effect, reducing the operating efficiency of the system, and even failing to operate normally. In addition, although the operation cost of the ground source heat pump system is low, the initial investment is high. Therefore, how to reasonably reduce the initial investment and operation cost is also a problem in the application of the ground source heat pump system.

Contents of the invention

my country's building heating areas are mainly concentrated in severe cold and cold areas, including Northeast, North and Northwest regions, which account for about 70% of my country's land area. In order to explore new heating technologies and alternative energy sources that are suitable for the vast northern regions, hot water solar heating, ground source heat pumps, and low-temperature power generation technologies are organically coupled together to form a comprehensive utilization system of solar shallow geothermal energy to realize solar energy resources throughout the year. Maximum range and cross-season utilization, heating during the heating period, power generation and energy storage during the non-heating period, and domestic hot water can also be provided as needed. Effectively solve the technical difficulties in traditional solar heating systems such as low operating temperature, large collector installation area, need to add auxiliary heat sources, difficulty in energy storage and excess heat in non-heating periods, as well as the imbalance of cold and heat in the ground source heat pump heating system and the initial Higher investment issues.

In order to solve the above technical problems, a hot water type solar shallow geothermal energy cogeneration integrated system proposed by the present invention includes a water storage tank, a first water pump, a solar heat collector, a low-level side heat exchanger, and a compression-expansion dual-function Machine head, permanent magnet electric power generation integrated motor, high side heat exchanger, expansion valve, working medium pump, underground low heat source heat sink system and second water pump; the above-mentioned equipment and valve body are connected by connecting pipelines, connected The relationship is: the water storage tank is provided with two coils, so that the cavity of the water storage tank is divided into a shell side, a first tube side and a second tube side, and the shell side of the water storage tank is provided with two A group of inlets and outlets, the outlet end of the solar heat collector passes through the shell side of the water storage tank, passes through the first water pump, and then connects to the inlet end of the solar heat collector to form a solar hot water circulation pipeline; The shell side of the water storage tank is connected to the water side of the high side heat exchanger through the second water pump to form a ground source heat pump hot water circulation pipeline; the first tube side of the water storage tank is connected in series on the heating supply-return water pipeline , the second tube side of the water storage tank is connected in series between the tap water pipeline and the domestic hot water pipeline; the heating water supply pipeline, the heating return water pipeline, the tap water pipeline and the domestic hot water pipeline are all provided with shut-off valves; The compression-expansion dual-function head is connected to the integrated permanent magnet motor; the outlet end of the working medium side of the low-level heat exchanger is connected to the high-level heat exchanger The inlet end of the working medium side of the heat exchanger, the outlet end of the working medium side of the high-level heat exchanger and the inlet end of the working medium side of the low-level heat exchanger are connected in parallel with a first bypass and a second bypass , wherein an expansion valve is provided on the first bypass, a cut-off valve is provided at the inlet of the expansion valve on the first bypass, and a heat pump check valve is provided at the outlet of the expansion valve, thereby forming a ground source Heat pump working medium side circulation pipeline; a working medium pump is provided on the second bypass, a shut-off valve is provided at the inlet of the working medium pump on the second bypass, and a power generation valve is provided at the outlet of the working medium pump. A one-way valve to form a low-temperature power generation medium-side circulation pipeline; the water side of the low-level heat exchanger is connected in series to the water supply-return pipeline of the underground low-level heat source heat sink system.

Using the above hot water type solar shallow geothermal energy combined heat and power integrated system, by adjusting the conduction or closing of the valve, the use of solar ground source heat pumps for heating and hot water during the heating period, and the use of solar energy to generate electricity and provide heat during the non-heating period Water; that is, in the heating period, close the shut-off valve on the second bypass, and at the same time, open the other shut-off valves to enter the solar ground source heat pump heating and hot water supply mode; in the non-heating period, close the heating water supply pipeline, heating The shut-off valves on the return water pipeline and the first bypass, at the same time, open the other shut-off valves, and enter the hot water type solar power generation hot water supply mode to run.

Further speaking, the steps of the present invention to realize the heating and hot water supply operation of the solar ground source heat pump are: start the first water pump to drive the water in the water storage tank into the solar heat collector to absorb heat and raise the temperature, and send it back to the water storage tank to complete the solar hot water cycle ; At the same time, start the permanent magnet electric power generation integrated motor to operate in electric mode, drive the compression expansion dual-function head to operate in compression mode, pressurize and heat up the dry saturated gaseous organic working fluid generated in the low-level side heat exchanger, and then enter the high-level side for heat exchange The heat released in the device condenses into a saturated liquid, passes through the stop valve on the first bypass, enters the expansion valve to depressurize and cool down into a low-dryness wet vapor, and then is introduced into the low-side heat exchanger after passing through the check valve of the heat pump. The heat is evaporated into dry saturated steam to complete the working fluid side circulation of the ground source heat pump; on the low-level water side of the ground-source heat pump, the low-level heat source water prepared by the underground low-level heat source heat sink system enters the low-level side heat exchanger through the heat source water supply pipeline to release heat After cooling down, return the heat source water return line to the underground low-level heat source heat sink system to complete the cycle; start the second water pump on the high-level water side of the ground-source heat pump, and pump the water in the water storage tank into the high-level side heat exchanger to absorb heat and raise the temperature After that, it is sent to the water storage tank to complete the hot water cycle of the ground source heat pump; the heating return water enters the first tube side of the water storage tank to absorb heat and heat up, and then is discharged as heating water to complete the heating water cycle; tap water enters the second tube side of the water storage tank to absorb heat. After the heat is heated up, it is discharged to provide domestic hot water.

The steps of the present invention to realize the hot water supply operation of hot water type solar power generation are: start the first water pump to drive the water in the water storage tank into the solar heat collector to absorb heat and raise the temperature, and then send it back to the water storage tank to complete the solar hot water cycle, which is used for low temperature Power generation and domestic hot water supply; start the working medium pump, the saturated liquid organic working medium generated in the low side heat exchanger enters the working medium pump through the shut-off valve (V6) and is pressurized and heated, then enters the high side through the power generation check valve The heat absorbed in the heat exchanger is evaporated into high-pressure and high-temperature dry saturated steam, which enters the compression-expansion dual-function head to operate in expansion mode, and at the same time drives the permanent magnet electric power generation integrated motor to operate in power generation mode to generate and output electric energy. After expansion, the low-pressure and low-temperature The gaseous working medium enters the low-level side heat exchanger and condenses into a saturated liquid to complete the low-level power generation working medium side circulation; on the low-level water side of low-temperature power generation, the low-level cold source water prepared by the underground low-level heat source heat sink system enters the low-level low-level water through the cold source water supply pipeline. After the side heat exchanger absorbs heat and heats up, it returns from the cold source water return pipe to the underground low-level heat source heat sink system to complete the cycle; on the high-level water side of low-temperature power generation, start the second water pump to pump the water in the water storage tank into the high-level side heat exchanger After cooling down in the medium heat, it is sent back to the water storage tank to complete the low-temperature hot water cycle for power generation; tap water enters the second tube in the water storage tank to absorb heat and heat up, and then discharged to provide domestic hot water.

Compared with prior art, the beneficial effect of the present invention is:

The hot water type solar shallow geothermal energy combined heat and power integrated system and operation method proposed by the present invention use the organic coupling of hot water type solar heating, ground source heat pump and organic Rankine cycle low-temperature power generation technology to form a comprehensive solar shallow geothermal energy Take advantage of the system. Realize heating during the heating period, implement solar thermal power generation and store energy underground in the non-heating period, and also provide domestic hot water throughout the year as needed. Its main beneficial effects are as follows:

1. The hot water type solar shallow geothermal energy combined heat and power integrated system uses solar energy and shallow geothermal energy to realize heating during the heating period, generate electricity during the non-heating period, and supply hot water throughout the year. It is suitable for heating in the vast northern regions of my country The new application technology of renewable energy can effectively improve the dual pressure on energy and environment brought by traditional heating methods. At the same time, the organic coupling of the ground source heat pump and the low-temperature power generation system also reduces the initial investment of the conventional solar ground source heat pump combined heating system and the energy waste and economic loss caused by long-term idle equipment.

2. The hot water type solar shallow geothermal energy combined heat and power integrated system effectively solves the traditional solar heating system operation caused by low solar energy flux density, limited sunshine time, easy to be affected by climate, and energy imbalance in winter and summer. The temperature is low, the installation area of the heat collector is large, it is necessary to add an auxiliary heat source, it is difficult to store energy, and there are problems such as excess heat in the non-heating period. For example, if a common radiator is used at the heating end of a building, the heating temperature is required to be above 70°C. However, for a large number of solar collectors sold on the market, the heat collection temperature in winter is generally between 50-70°C. Therefore, most conventional solar heating system terminal forms use floor radiation systems or water-air treatment equipment with lower water supply temperature requirements, but the cost is relatively high. However, this system can adjust the hot water temperature of the water storage tank in a timely manner by regulating the operation status of the ground source heat pump, so that the heating water supply can meet the temperature requirements of various terminal equipment; solar heating often requires a larger area of solar collectors, but for Most of the buildings do not have enough space to install solar collectors that can bear the load of the entire building, which requires the addition of auxiliary heat sources, commonly used are electric heating, coal-fired, gas-fired, firewood-fired boilers, heat pump heating, etc., resulting in The solar guarantee rate of the system is relatively low, and no real renewable energy heating has been realized. In this system, the ground source heat pump is used as the second heat source of the solar heating system, which is a pure clean energy heating technology utilizing solar energy and shallow geothermal energy. In the non-heating period, the low-temperature power generation technology is used to store solar energy in shallow geothermal energy, while in the heating period, the ground source heat pump is used to extract the solar energy stored in the ground for heating, so as to realize the heating of solar collectors with low area and large load technology. Therefore, according to the actual situation of the building, the installation area of solar collectors can be greatly reduced; the immature supporting energy storage technology is an important reason for the slow development of solar heating systems in my country. However, this system reduces the guaranteed rate of solar energy according to the actual building conditions. It mainly uses ground source heat pumps and solar energy for heating at the same time, so that the entire heating process is controllable and adjustable. There is no need for solar energy storage devices, and the system has high reliability; solar energy is not balanced in seasons. It will cause a lot of waste of heat in the non-heating period, and will also cause damage to the system. Therefore, the excess heat in the non-heating season has seriously affected the development of solar heating. And this system is based on Organic Rankine Cycle Utilization of a large amount of low-temperature hot water generated by solar collectors in the non-heating period to output clean electricity for building use, and store the remaining heat in shallow geothermal energy for building heating during the heating period. It realizes the maximization of solar energy, cross-seasonal application, and completely solves the problem caused by excess heat in the non-heating period.

3. The hot water type solar shallow geothermal energy combined heat and power integrated system effectively solves the shortcomings of the traditional ground source heat pump heating system running alone, cold and hot imbalance and high initial investment. For example, my country's building heating areas are mainly concentrated in severe cold and cold areas, and the building heating load is often greater than the cooling load, and even many areas have no cooling demand, coupled with the domestic hot water demand of some buildings, resulting in a building heating load that is significantly greater than the cooling load. If the ground source heat pump is used alone for building heating, it will seriously lead to the uneven income and expenditure of underground heat. Long-term operation will cause the underground environment to deviate from the original equilibrium state, forming a cold and heat island effect, reducing the operating efficiency of the system, and even failing to operate normally. This system organically couples solar heating, ground source heat pump and low-temperature power generation technology, and rationally designs to make the heat emitted and absorbed underground equal, so as to avoid thermal pollution of shallow geothermal energy and ensure the efficient and economical operation of the entire system; In addition, compared with the ground source heat pump heating system that operates independently, the initial investment of this system is relatively low, and clean electric energy can be obtained for building use during the non-heating period.

Description of drawings

Fig. 1 is a schematic diagram of the hot water type solar shallow geothermal energy combined heat and power integrated system of the present invention;

In the picture:

1-water storage tank 2-first water pump 3-solar collector

4-Low side heat exchanger 5-Compression and expansion dual-function head 6-Permanent magnet electric generator integrated motor

7-High side heat exchanger 8-Expansion valve 9-Working fluid pump

10-Underground low-level heat source heat sink system 11-The second water pump V1～V6-all are stop valves

C1-heat pump check valve C2-power generation check valve

detailed description

The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the described specific embodiments are only for explaining the present invention, and are not intended to limit the present invention.

The design idea of the present invention is: organically couple hot water type solar heating, ground source heat pump and organic Rankine cycle low-temperature power generation technology together to form a comprehensive utilization system of solar shallow geothermal energy, and complete the heat generation of solar energy and shallow geothermal energy. Output or storage, to achieve heating during the heating period, power generation and energy storage during the non-heating period. At the same time, it can also provide domestic hot water throughout the year as needed to maximize the use of solar energy resources throughout the year and across seasons. In the heating period, the heating process of solar energy and shallow geothermal energy is used to realize the cooling of shallow geothermal energy, which provides a high-quality cold source for the subsequent solar thermal power generation system; in the non-heating period, the thermal power generation process of solar energy is used to store heat underground for The ground source heat pump provides a high-quality low-level heat source for the next heating period. Compared with traditional solar energy and ground source heat pump heating systems, this system has dual functions of heating and power generation, and can be operated throughout the year. At the same time, it ensures the cold and heat balance of the ground source system during the long-term operation of the equipment, and achieves the effect of production capacity .

As shown in Figure 1, a hot water type solar shallow geothermal energy cogeneration integrated system proposed by the present invention includes a water storage tank 1, a first water pump 2, a solar collector 3, a low side heat exchanger 4, Compression-expansion dual-function head 5, permanent magnet electric generator integrated motor 6, high-level side heat exchanger 7, expansion valve 8, working medium pump 9, underground low-level heat source heat sink system 10, and second water pump 11.

The above-mentioned equipment and the valve body are connected by connecting pipelines, and the connection relationship is as follows:

The water storage tank 1 is provided with two coils, so that the cavity of the water storage tank 1 is divided into a shell side, a first tube side and a second tube side, and the shell side of the water storage tank 1 is provided with two A group of inlets and outlets, the outlet end of the solar heat collector 3 passes through the shell side of the water storage tank 1, passes through the first water pump 2, and then connects to the inlet end of the solar heat collector 3 to form a solar hot water cycle Pipeline: the shell side of the water storage tank 1 is connected to the water side of the high side heat exchanger 7 through the second water pump 11 to form a ground source heat pump hot water circulation pipeline.

The first tube side of the water storage tank 1 is connected in series on the heating supply-return water pipeline, and the second tube side of the water storage tank 1 is connected in series between the tap water pipeline and the domestic hot water pipeline; the heating water supply pipeline is provided with a cut-off Valve V1, shut-off valve V2 is set on the heating return water pipeline, shut-off valve V3 is set on the tap water pipeline, and shut-off valve V4 is set on the domestic hot water pipeline.

The compression-expansion dual-function head 5 is connected to the permanent magnet electric generator integrated motor 6; the outlet end of the working medium side of the low-level heat exchanger 4 passes through the compression-expansion dual-function head 5 and then is connected to The inlet end of the working medium side of the high-level heat exchanger 7, the outlet end of the working medium side of the high-level heat exchanger 7 and the inlet end of the working medium side of the low-level heat exchanger 4 are connected in parallel with a second A bypass and a second bypass, wherein an expansion valve 8 is provided on the first bypass, a cut-off valve V5 is provided at the inlet of the expansion valve 8 on the first bypass, and a cut-off valve V5 is located at the outlet of the expansion valve 8 A heat pump check valve C1 is provided at the heat pump to form a circulating pipeline on the working medium side of the source heat pump; a working medium pump 9 is provided on the second bypass, and a cut-off valve is provided at the inlet of the working medium pump 9 on the second bypass The valve V6 is located at the outlet of the working medium pump 9 and is provided with a power generation check valve C2, thereby forming a low-temperature power generation working medium side circulation pipeline;

The water side of the low-level heat exchanger 4 is connected in series to the water supply-return pipeline of the underground low-level heat source heat sink system 10 .

It should be emphasized that the compression-expansion dual-function handpiece 5 in the present invention mainly realizes the compression and expansion process of the working medium by using the forward and reverse operation of equipment such as piston machine, scroll machine, screw machine and centrifuge. The integrated permanent magnet motor 6 utilizes the forward and reverse functions of the permanent magnet motor to realize the drive and power generation process. For example, when the permanent magnet motor rotates in the positive direction to drive the head to do work, the compression-expansion dual-function head performs the compression process, and the system enters the heat pump operation mode. Conversely, when the compression-expansion dual-function head 2 runs in the opposite direction to carry out the expansion process, the permanent magnet motor can be driven to generate power, and the system enters the power generation operation mode.

In summary, the hot water type solar shallow geothermal energy combined heat and power integrated system of the present invention can be divided into four main types: solar hot water system, ground source heat pump low temperature power generation integrated system, heating water system and domestic hot water supply system. part. Among them, the solar hot water system is mainly composed of a water storage tank 1, the first water pump 2, and a solar collector 3; the ground source heat pump low-temperature power generation integrated system is composed of a low-side heat exchanger 4, a compression expansion dual-function head 5, and a permanent magnet Electric power generation integrated motor 6, high-side heat exchanger 7, expansion valve 8, working fluid pump 9, two check valves, second water pump 11, and underground low-level heat source heat sink system 10; the heating water system consists of heating The return water pipeline, the water storage tank 1 and the building heating system are composed of; the domestic hot water supply system is composed of the tap water pipeline, the domestic hot water supply pipeline, the water storage tank 1 and the building hot water supply system.

In the heating period, the ground source heat pump low-temperature power generation integrated system operates in the ground source heat pump mode, extracts heat from underground low-level heat sources (soil, groundwater, surface water, etc.) and improves its grade, and combines low-temperature solar collectors to provide heating for buildings , while supplying domestic hot water. In the non-heating period, the system switches to the low-temperature power generation operation mode. Under the premise of ensuring domestic hot water for users, shallow geothermal energy such as soil, groundwater, and surface water is used as a cold source (heat sink), and the solar collector The absorbed low-temperature heat energy is partially converted into electrical energy through the organic Rankine cycle for building use. At the same time, the heat released in the condenser is stored underground to make up for the heat loss during the heating period, ensure the balance of underground heat balance, and avoid the formation of underground hot and cold island effects. , contaminating shallow geothermal energy.

Using the hot water type solar shallow geothermal energy combined heat and power integrated system shown in Figure 1, by adjusting the conduction or closing of the valve, the use of solar ground source heat pumps for heating and hot water during the heating period, and the use of solar energy during the heating period Power generation provides hot water; that is, in the heating period, close the cut-off valve V6 on the second bypass, and at the same time, open the other five cut-off valves, namely V1 to V5, to enter the heating and hot water supply mode of the solar ground source heat pump; in the non-heating period During the period, close the stop valve V1 on the heating water supply pipeline, the stop valve V2 on the heating return line, and the stop valve V5 on the first bypass. At the same time, open the other three stop valves, namely V3, V4 and V6, to enter the hot water Type solar power generation hot water supply mode operation.

The steps to realize the operation of solar ground source heat pump heating and hot water supply are:

Start the first water pump 2 to pump the water in the water storage tank 1 into the solar heat collector 3 to absorb heat and heat up and send it back to the water storage tank 1 to complete the solar hot water cycle; at the same time, start the permanent magnet electric power generation integrated motor 6 to operate in electric mode The operation drives the compression-expansion dual-function head 5 to operate in the compression mode. The dry saturated gaseous organic working medium generated in the low-level heat exchanger 4 is pressurized and heated, and then enters the high-level heat exchanger 7 to release heat and condense into a saturated liquid. The cut-off valve V5 on the side road enters the expansion valve 8 to depressurize and cool down into low-dryness wet steam, and then, after passing through the heat pump check valve C1, it is introduced into the low-side heat exchanger 4 to absorb heat and evaporate into dry saturated steam. Complete the working fluid side circulation of the ground source heat pump; on the low-level water side of the ground-source heat pump, the low-level heat source water prepared by the underground low-level heat source heat sink system 10 enters the low-level side heat exchanger 4 through the heat source water supply pipeline to release heat and cool down from the heat source water The return water pipeline returns to the underground low-level heat source heat sink system 10 to complete the cycle; on the high-level water side of the ground-source heat pump, the second water pump 11 is started, and the water in the water storage tank 1 is pumped into the high-level side heat exchanger 7 to absorb heat and heat up Send it into the water storage tank 1 to complete the hot water cycle of the ground source heat pump; the heating return water enters the first tube in the water storage tank 1 through the cut-off valve V2 to absorb heat and heat up, and then discharges through the cut-off valve V1 to provide heating water to complete the heating water cycle; the tap water passes through the cut-off valve The valve V4 enters the second tube in the water storage tank 1 to absorb heat and heat up, and then discharge through the stop valve V3 to provide domestic hot water.

The steps to realize the hot water heating operation of solar power generation are:

Start the first water pump 2 to pump the water in the water storage tank 1 into the solar heat collector 3 to absorb heat and heat up, then send it back to the water storage tank 1 to complete the solar hot water cycle, which is used for low-temperature power generation and domestic hot water supply; start the working medium pump 9 , the saturated liquid organic working fluid produced in the low side heat exchanger 4 passes through the stop valve (V6) and enters the working fluid pump 9 to be pressurized and heated up, and then enters the high side heat exchanger 7 through the power generation check valve C2 to absorb heat and evaporate It is high-pressure and high-temperature dry saturated steam, which enters the compression-expansion dual-function head 5 to operate in expansion mode, and drives the permanent magnet electric generator integrated motor 6 to operate in power generation mode to generate and output electric energy, and the expanded low-pressure and low-temperature gaseous working medium enters the low position The side heat exchanger 4 is condensed into a saturated liquid to complete the side circulation of the low-level power generation working medium; on the low-level water side of the low-temperature power generation, the low-level cold source water prepared by the underground low-level heat source heat sink system 10 enters the low-level side for heat exchange through the cold source water supply pipeline After the device 4 absorbs heat and heats up, it returns from the cold source water return line to the underground low-level heat source heat sink system 10 to complete the cycle; on the high-level water side of low-temperature power generation, start the second water pump 11 to pump the water in the water storage tank 1 into the high-level side for heat exchange After cooling down in the device 7, it is sent back to the water storage tank 1 to complete the low-temperature power generation hot water cycle; the tap water enters the second tube in the water storage tank 1 through the shut-off valve V4 to absorb heat and heat up, and then is discharged through the shut-off valve V3 to provide domestic hot water.

Research materials: Taking Shenyang City as an example, the economic and environmental benefits generated by the hot water type solar shallow geothermal energy combined heat and power integrated system of the present invention are analyzed as follows.

Shenyang City is located at 123.4° east longitude and 41.8° north latitude. It is an area rich in solar energy resources in China. The annual radiation on the horizontal plane is between 3780-5040MJ/m ² , which is equivalent to the heat emitted by burning 129-172kg standard coal. The annual average daily radiation on the local latitude plane is 14.98MJ/(m ² ·d), and the monthly average daily radiation on the local latitude plane in December is 11.437MJ/(m ² ·d). Shenyang City belongs to the severe cold area of my country's building climate division, and the number of heating period days used for design calculation is 152 days.

Since different building types have different demands for domestic hot water, the supply of domestic hot water is not involved in this calculation. Under the premise of ensuring that the integrated system of ground source heat pump low-temperature power generation is equal to the amount of heat emitted to the ground and the heat absorbed, the monthly average daily radiation on a plane with an inclination equal to the local latitude is used to conduct a 100m ² solar collector lighting area. Calculation of heat supply in the heating period and power generation in the non-heating period of the geothermal energy combined heat and power integrated system. Among them, the working efficiency of solar collectors based on the daylighting area is 50%; the heat loss rate of pipelines and water tanks is 10%; The heat supply coefficient of the model unit is 4.0; the heat consumption index of the existing buildings in Shenyang is 32.61W/m ² ; the heating metering price is 0.25 yuan per kWh; KWh is 1.15 yuan; in addition, the conversion coefficient of heat power and standard coal is calculated according to the heat equivalent value, while the conversion coefficient of electric power is 0.315kg/(kW·h) according to the 2016 annual development report of the power industry, and the unit standard is taken at the same time. Coal _CO2 emissions are 2.65kg/kg, SO2 emissions are _1.49g /kg, and _NOx emissions are 1.37g/kg. The relevant calculation results are shown in Table 1.

Table 1 Calculation results of economic and environmental benefits of hot water solar shallow geothermal energy combined heat and power integrated system

It can be drawn from Table 1 that, taking Shenyang City as an example, for a solar collector lighting area of 100m2, the heating period of the hot water type solar shallow geothermal energy cogeneration integrated system proposed by the present invention is ^76111kW h , can meet the heating demand of 674m ² construction area. Compared with the traditional central heating system, the total annual economic income of this system is 15,952 yuan (the total annual economic income = heating saving cost during the heating period - power consumption cost of the ground source heat pump during the heating period + low-temperature power generation during the non-heating period electricity income), save 6126kg of standard coal, and reduce CO ₂ , SO ₂ , and NOx emissions by 16,234kg, 9,128g, and 8,393g, respectively. It can be seen that the implementation of the hot water solar shallow geothermal energy combined heat and power integrated system will bring huge economic and environmental benefits.

Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments, and the above-mentioned specific embodiments are only illustrative, rather than restrictive. Under the enlightenment of the present invention, many modifications can be made without departing from the gist of the present invention, and these all belong to the protection of the present invention.

Claims (4)

1. A hot water type solar shallow geothermal energy cogeneration integrated system, characterized in that it comprises a water storage tank (1), a first water pump (2), a solar heat collector (3), and a low side heat exchanger (4), compression and expansion dual-function head (5), permanent magnet electric generator integrated motor (6), high-level side heat exchanger (7), expansion valve (8), working fluid pump (9), underground low-level heat source Heat sink system (10) and second water pump (11); The above-mentioned equipment and the valve body are connected by connecting pipelines, and the connection relationship is as follows: The water storage tank (1) is provided with two coils, so that the cavity of the water storage tank (1) is divided into a shell side, a first tube side and a second tube side, and the water storage tank (1) There are two sets of inlets and outlets on the shell side of the solar collector (3), and the outlet end of the solar collector (3) passes through the shell side of the water storage tank (1), passes through the first water pump (2), and is connected to the solar collector. The inlet end of the heater (3) forms a solar hot water circulation pipeline; the shell side of the water storage tank (1) is connected to the water side of the high side heat exchanger (7) through the second water pump (11), Form a ground source heat pump hot water circulation pipeline; The first pipe pass of the water storage tank (1) is connected in series on the heating supply-return water pipeline, and the second pipe pass of the water storage tank (1) is connected in series between the tap water pipeline and the domestic hot water pipeline; the heating water supply pipe There are cut-off valves on the road, heating return water pipeline, tap water pipeline and domestic hot water pipeline; The compression-expansion dual-function head (5) is connected to the integrated permanent magnet motor (6); the outlet end of the working medium side of the low-level heat exchanger (4) passes through the The machine head (5) is then connected to the inlet end of the working medium side of the high-level heat exchanger (7), and the outlet end of the working medium side of the high-level heat exchanger (7) exchanges heat with the low-level side The inlet end of the working fluid side of the device (4) is connected in parallel with a first bypass and a second bypass, wherein an expansion valve (8) is provided on the first bypass, and an expansion valve (8) is located on the first bypass. A cut-off valve (V5) is provided at the inlet of the expansion valve (8), and a heat pump check valve (C1) is provided at the outlet of the expansion valve (8), thereby forming a ground source heat pump working fluid side circulation pipeline; the second bypass is provided with There is a working fluid pump (9), on the second bypass, a cut-off valve (V6) is arranged at the inlet of the working fluid pump (9), and a power generation unit is arranged at the outlet of the working fluid pump (9) Directional valve (C2), thus forming a low-temperature power generation medium side circulation pipeline; The water side of the low-level heat exchanger (4) is connected in series to the water supply-return pipeline of the underground low-level heat source heat sink system (10). 2. A hot water type solar shallow geothermal energy cogeneration operation method, characterized in that, utilizing the hot water type solar shallow geothermal energy cogeneration integrated system as claimed in claim 1, by adjusting the conduction of the valve Or shut down, realize the use of solar ground source heat pump to heat and supply hot water during the heating period, and use solar energy to generate electricity and provide hot water during the non-heating period; including: In the heating period, close the cut-off valve (V6) on the second bypass, and at the same time, open the other cut-off valves to enter the heating and hot water supply mode of the solar ground source heat pump; In the non-heating period, close the cut-off valves set on the heating water supply pipeline, heating return water pipeline and the first bypass, and at the same time, open other cut-off valves to enter the hot water solar power generation hot water supply mode. 3. According to the hot water type solar shallow geothermal energy cogeneration method according to claim 2, it is characterized in that, to realize the heating and hot water operation of the solar ground source heat pump, the steps are as follows: Start the first water pump (2) to pump the water in the water storage tank (1) into the solar heat collector (3) to absorb heat and heat up and send it back to the water storage tank (1), completing the solar hot water cycle; At the same time, start the permanent magnet electric generator integrated motor (6) to operate in the electric mode to drive the compression expansion dual-function head (5) to operate in the compression mode to convert the dry saturated gaseous organic working fluid produced in the low side heat exchanger (4) After the pressure rises, it enters the high side heat exchanger (7) to release heat and condense into a saturated liquid, then passes through the cut-off valve (V5) on the first bypass, enters the expansion valve (8) to reduce the pressure and temperature to become a low-quality wet vapor, and then, After passing through the heat pump check valve (C1), it is introduced into the low side heat exchanger (4) to absorb heat and evaporate into dry saturated steam, completing the ground source heat pump working fluid side cycle; On the low-level water side of the ground source heat pump, the low-level heat source water prepared by the underground low-level heat source heat sink system (10) enters the low-level side heat exchanger (4) through the heat source water supply pipeline, and then returns to the low-level side heat exchanger (4) through the heat source water return pipeline The underground low-level heat source heat sink system (10) completes the cycle; On the high-level water side of the ground source heat pump, start the second water pump (11), pump the water in the water storage tank (1) into the high-level side heat exchanger (7) to absorb heat and heat up, and then send it to the water storage tank (1) to complete the ground Source heat pump hot water circulation; The heating return water enters the first tube in the water storage tank (1) to absorb heat and heat up, and then is discharged as heating water supply, completing the heating water cycle; Tap water enters the second pipe pass in the water storage tank (1) to absorb heat and heat up, and then discharges to provide domestic hot water. 4. According to claim 2 or 3, the hot water type solar shallow geothermal energy cogeneration operation method is characterized in that, to realize the hot water type solar power generation and hot water supply operation, the steps are as follows: Start the first water pump (2) to pump the water in the water storage tank (1) into the solar collector (3) to absorb heat and heat up, then send it back to the water storage tank (1) to complete the solar hot water cycle, which is used for low-temperature power generation and domestic heat water supply; Start the working medium pump (9), the saturated liquid organic working medium produced in the low side heat exchanger (4) enters the working medium pump (9) through the shut-off valve (V6) and is pressurized and heated, then passes through the power generation check valve (C2 ) into the high-level side heat exchanger (7) to absorb heat and evaporate into high-pressure and high-temperature dry saturated steam, enter the compression-expansion dual-function head (5) to operate in expansion mode, and drive the permanent magnet motor (6) at the same time Operate in power generation mode to generate and output electric energy, and the expanded low-pressure and low-temperature gaseous working medium enters the low-level side heat exchanger (4) to condense into a saturated liquid to complete the low-temperature power generation working medium side cycle; On the low-level water side of low-temperature power generation, the low-level cold source water prepared by the underground low-level heat source heat sink system (10) enters the low-level side heat exchanger (4) through the cold source water supply pipeline To the underground low-level heat source heat sink system (10) to complete the cycle; On the high-level water side of low-temperature power generation, start the second water pump (11) to drive the water in the water storage tank (1) into the high-level side heat exchanger (7) to release heat and cool down, and then send it back to the water storage tank (1), completing the low-temperature power generation heat water cycle; Tap water enters the second pipe pass in the water storage tank (1) to absorb heat and heat up, and then discharges to provide domestic hot water.