Rural household type energy supply method and system and fire wall

Abstract

The invention discloses a rural household energy supply method and system and a fire wall. The system constructs a comprehensive energy system framework of a rural planting and breeding combined mode based on biological marsh gas energy, distributed photovoltaic power supply (light energy), air energy and the fire wall. One part of the biogas serving as driving energy is used for burning and heating the fire wall to supply heat to the greenhouse, and the other part is used for daily cooking of farmers; solar power generation drives the heat pump to produce hot water, one part of the hot water is used for heating farmer residential areas and supplying domestic hot water, and the other part of the hot water is used for enhancing the heating effect of a fire wall. According to the comprehensive energy system constructed by the invention, electricity utilization and heat supply of farmers can be met in a clean and low-carbon manner, and the yield of crops in the greenhouse can be increased at the same time. The light-gas synergistic ecological agricultural system provided by the invention realizes sustainable agricultural development with low carbon emission, low cost, high yield and resource circulation, and has important significance for constructing a clean and low-carbon energy system in rural areas in the future.

Description

Technical Field

[0001] This invention relates to the field of smart green agriculture technology, and in particular to rural household energy supply methods, systems, and firewalls. Background Technology

[0002] Distributed energy systems are miniaturized, modular energy supply systems based on user demand and located close to load centers. By integrating multiple energy sources, such as renewable energy and clean fuels, with energy storage technologies, they achieve localized production, efficient utilization, and flexible dispatch of various energy forms, including electricity, heat, and cooling. They emphasize on-site energy consumption and cascade utilization. Currently, there are many successful examples of biogas and solar energy applications in distributed energy systems, which have not only improved rural energy utilization rates but also positively impacted the living standards of rural residents.

[0003] However, establishing distributed energy systems in rural areas through the safe and efficient use of low-carbon, clean, and renewable energy sources is crucial. Traditional energy systems lack synergistic development among renewable energy sources, resulting in low energy utilization rates that fail to meet farmers' needs, necessitating an urgent upgrade of rural energy systems.

[0004] Therefore, based on the above-mentioned problems, this invention develops an integrated energy supply system that realizes "one energy for multiple uses and multi-energy synergy", achieving efficient utilization of solar energy and biogas. Summary of the Invention

[0005] This invention provides a rural household energy supply method, system, and firewall, aiming to solve the problems mentioned above, such as the lack of coordinated development among renewable energy sources in existing traditional energy systems, low energy utilization rates, inability to meet the needs of farmers, and the urgent need to upgrade rural energy.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: Rural household energy supply methods include the following steps: Hybrid power supply: Both the solar power generation module and the public power grid supply power to the air source heat pump through transformers, and the solar power generation module and the public power grid can be switched. The solar power generation module is given priority in power supply, and the public power grid is used when there is insufficient sunlight. Composite heating: The air source heat pump circulates and heats the water in the hot water storage tank. The heated water in the hot water storage tank and the biogas generator both provide heating for the farmers' residential areas and greenhouses. The hot water storage tank and the biogas generator can be switched. Gradual heating: Set application scenarios and allocate heating priority to hot water storage tanks and biogas generators in sequence according to the application scenarios, with hot water storage tanks giving priority to heating farmers' residential areas.

[0007] Preferably, the gradient heating includes the following application scenarios and corresponding gradients: When the ambient temperature is high: both the hot water storage tank and the biogas generator prioritize heating the farmers' residential area. After meeting the needs of the farmers' residential area, excess heat and biogas are transferred to the greenhouse. When the ambient temperature is low: the hot water storage tank prioritizes heating the farmers' residential area. After meeting the needs of the farmers' residential area, excess heat is transferred to the greenhouse. The biogas generator prioritizes heating the greenhouse. After meeting the needs of the greenhouse, excess biogas is transferred to the farmers' residential area.

[0008] Preferably, the ambient temperature threshold for the gradient heating is 0°C. When the lowest ambient temperature throughout the day is ≥0°C, the ambient temperature is considered relatively high. When the lowest ambient temperature throughout the day is <0°C, the ambient temperature is considered relatively low.

[0009] A rural household energy supply system, used for implementing the aforementioned rural household energy supply method, includes: The solar power generation module and the public power grid are used for combined power supply. Both the solar power generation module and the public power grid are electrically connected to the transformer, and the transformer is electrically connected to the air source heat pump. The air source heat pump forms a water circulation with the hot water storage tank through a circulation pipeline, and the water in the hot water storage tank is heated by the air source heat pump through circulation. The hot water storage tank forms a water circulation system with the fan coil units and hot water pipes in the farmers' residential area and the firewall of the greenhouse through two different circulation pipelines. The water in the hot water storage tank also exchanges heat with the fan coil units, hot water pipes and firewall. The biogas generator is connected to the biogas stove in the farmer's residential area and the fire wall in the greenhouse through two different biogas delivery pipelines. The hot water produced by the biogas stove is connected in parallel to the fan coil and hot water circulation pipeline, and the fire wall ignites the biogas for heating.

[0010] Preferably, the solar power generation module includes a distributed photovoltaic system arranged on the roof, which absorbs solar energy and converts it into alternating current through a photovoltaic inverter and a transformer.

[0011] Preferably, the circulating pipelines all have the same structure, each including an independent water supply pipe and a return pipe, each water supply pipe is equipped with a safety valve, and each return pipe is equipped with a circulating water pump.

[0012] A firewall, used as a component of the aforementioned rural household energy supply system, provides heating for greenhouses, including: A hollow fire wall formed by stacking bricks vertically, the fire wall having a backfill area filled with heat-conducting material, and the backfill area having a flow channel and a combustion chamber that extend through the fire wall along the wall's extension direction. Each of the flow channels is equipped with a water supply pipe, and the water supply pipe forms a heat conduction with the backfill area. The inlet of the water supply pipe is connected to the outlet of the hot water storage tank. The combustion chamber is equipped with a biogas delivery pipeline and a biogas ignition device. The inlet of the biogas delivery pipeline is connected to the biogas generator. A biogas concentration monitoring system and a flow valve are sequentially installed on the biogas delivery pipeline along the biogas delivery direction. The biogas generator supplies biogas to the combustion chamber through the biogas delivery pipeline, which is then ignited by the biogas ignition device for combustion and heat supply. One side of the firewall is equipped with a control system including at least a controller, a biogas concentration monitoring system, a flow valve, a biogas ignition device, a safety valve for the circulation pipeline between the hot water storage tank and the firewall, and a circulating water pump, all of which are electrically connected to the control system.

[0013] Preferably, an axial flow fan is provided on the side of the fire wall away from the biogas inlet, and the water supply pipe passes through the axial flow fan and is connected to the return water pipe and flows back to the hot water storage tank to form a circulation. The combustion chamber is equipped with an exhaust pipe at the end furthest from the biogas inlet. The combustion chamber is connected to an axial flow fan through the exhaust pipe and forms an exhaust connection with the outside of the greenhouse. The combustion chamber is provided with several oxygen channels on both sides. The combustion chamber is connected to the greenhouse outside the fire wall through the oxygen channels, and the combustion chamber and the interior of the oxygen channels are connected by an axial flow fan to form a negative pressure.

[0014] Preferably, the axial flow fan outlet is equipped with a biogas concentration alarm. The biogas concentration alarm is used to sense the biogas concentration in the gas at the outlet of the exhaust pipe and to issue an alarm when the concentration exceeds a set value. The biogas concentration alarm is linked with the flow valve and the biogas ignition device through the control system.

[0015] Preferably, the biogas delivery pipeline is fixedly installed at the bottom of the combustion chamber by a fixed bracket. The top of the biogas delivery pipeline is provided with a biogas delivery port that communicates with the combustion chamber. A branch valve is provided on the biogas delivery port. The biogas ignition device is buried in the backfill area near the biogas delivery port. The ignition port of the biogas ignition device extends into the combustion chamber and is close to the end of the biogas delivery port to ignite the biogas.

[0016] The beneficial effects of this invention are: (1) The rural household energy system design method proposed in this invention utilizes the clean energy generated after the treatment of manure from livestock farms to replace fossil fuels, and connects the firewall and photovoltaic system to the greenhouse, which greatly improves the utilization rate of clean energy, realizes ecological cycle, and promotes sustainable agricultural development. (2) The rural household energy system design method proposed in this invention uses a photovoltaic system to convert solar energy into electricity to supply farmers' daily electricity use, drive an air source heat pump to realize winter heating for farmers, and assist in enhancing winter heating of greenhouses, effectively coping with extreme weather conditions. This invention not only solves the rural energy problem, but also greatly improves the living standards of rural residents. (3) At the same time, the traditional fire wall heating design is retained, and the reserved channel is used in conjunction with electric heating water. When the biogas concentration is insufficient, hot water heating can be switched to ensure heating efficiency and avoid pollution caused by simply using biomass combustion. When the biogas concentration is sufficient, biogas combustion heating is used to maintain low carbon and environmental protection as much as possible, and a balance is achieved between continuous heating and green environmental protection. The switching process is automatically switched by monitoring the biogas concentration, which improves self-control and flexibility. (4) The biogas concentration alarm can monitor whether the biogas is completely burned, while the flame detector can monitor whether the ignition is normal, thus improving the overall self-control of the device. When an abnormality occurs, the fire wall heating will be shut off and personnel will be notified to carry out maintenance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the rural household energy system design method of the present invention; Figure 2 This is a layout diagram of the distributed photovoltaic system of the present invention; Figure 3 This is a schematic diagram of the installation of the firewall of the present invention in a greenhouse; Figure 4 This is a cross-sectional schematic diagram of the firewall of the present invention; Figure 5 This is a cross-sectional schematic diagram of the combustion chamber of the present invention; Figure 6 This is a plan view of the firewall of the present invention; In the diagram: 1. Public power grid; 2. Distributed photovoltaic system; 3. Photovoltaic inverter; 4. Transformer; 5. Air source heat pump; 6. Circulating water pump; 7. Hot water storage tank; 8. Fan coil unit and hot water pipe; 9. Farm residential area; 10. Biogas delivery pipeline; 11. Biogas generator; 12. Greenhouse; 13. Firewall; 14. Water supply pipe; 15. Return water pipe; 16. Livestock farm; 17. Fixed support; 18. Biogas concentration monitoring system; 19. Flow valve; 20. Control system; 21. Axial flow fan; 22. Safety valve; 23. Flow channel; 24. Backfill area; 25. Brick wall; 26. Oxygen passage; 27. Combustion chamber; 28. Biogas delivery port; 29. ​​Branch valve; 30. Biogas ignition device; 31. Ignition port; 32. Flame detector; 33. Biogas concentration alarm; 34. Exhaust duct. Detailed Implementation

[0018] The embodiments will be further described below with reference to the accompanying drawings.

[0019] like Figures 3-6 As shown, in a preferred embodiment 1, a fire wall is used to heat the greenhouse 12. The fire wall 13 is a hollow fire wall 13 formed by stacking brick walls 25 in the vertical direction. The fire wall 13 has a backfill area 24 filled with heat-conducting material. The backfill area 24 is provided with a flow channel 23 and a combustion chamber 27 that extend through the fire wall 13 along the wall extension direction. Each of the flow channels 23 is equipped with a water supply pipe 14, and the water supply pipe 14 forms a heat conduction with the backfill area 24. The inlet of the water supply pipe 14 is connected to the outlet of the hot water storage tank 7. The combustion chamber 27 is equipped with a biogas delivery pipeline 10 and a biogas ignition device 30. The inlet of the biogas delivery pipeline 10 is connected to the biogas generator 11. The biogas delivery pipeline 10 is equipped with a biogas concentration monitoring system 18 and a flow valve 19 in sequence along the biogas delivery direction. The biogas generator 11 supplies biogas to the combustion chamber 27 through the biogas delivery pipeline 10, which is then ignited by the biogas ignition device 30 for combustion and heat supply. The firewall 13 is equipped with a control system 20, which includes at least a controller, on one side. The biogas concentration monitoring system 18, flow valve 19, biogas ignition device 30, and hot water storage tank 7 are all electrically connected to the control system 20 through the circulation pipeline between them and the firewall 13.

[0020] Brick wall 25 and earth filling area 24 are common structures of fire wall 13. This patent sets up flow channel 23 and combustion chamber 27 for two heating methods. The two methods are used in combination and can be switched automatically. The flow channel 23 is used for the installation of the water supply pipe 14 of the circulation pipeline of the hot water storage tank 7, for circulating hot water heating; The biogas delivery pipeline 10 is used to deliver biogas generator 11 to combustion chamber 27 at a constant flow rate through flow valve 19. Flow valve 19 is a solenoid valve. During the process, biogas concentration monitoring system 18 monitors the biogas concentration from biogas generator 11. Biogas concentration monitoring system 18 is a biogas concentration sensor. After the biogas in combustion chamber 27 is mixed with air, it is ignited by biogas ignition device 30 for combustion and heat supply. The combined use of the two methods is controlled by the programmable PLC controller within the control system 20.

[0021] As a preferred embodiment 2, the circulation pipeline between the flow valve 19, the biogas ignition device 30, the hot water storage tank 7, and the firewall 13 is linked with the biogas concentration monitoring system 18 through the control system 20, and the circulation pipeline and the biogas combustion line including the flow valve 19 and the biogas ignition device 30 are connected to form a "one-for-one" system through the biogas concentration monitoring system 18 and the control system 20.

[0022] Based on Example 2, the two methods can be used in combination as "one for backup and one for use". The biogas concentration monitoring system 18 monitors the biogas concentration from the biogas generator 11 in real time. When the biogas concentration is lower than the set value, the biogas concentration monitoring system 18 sends a signal to the controller of the control system 20. The controller closes the flow valve 19 and the biogas ignition device 30 to stop the biogas delivery and ignition, and then connects the circulation pipeline of the hot water storage tank 7 to the water supply pipe 14 to use the circulating hot water for heating to ensure continuous heating. When the biogas concentration is higher than the set value, the biogas concentration monitoring system 18 sends a signal to the controller of the control system 20. The controller closes the circulation pipeline of the hot water storage tank 7 and then starts the flow valve 19 and the biogas ignition device 30 to deliver biogas and ignite it. The biogas combustion is used to provide heat in relay, ensuring continuous heating, while being green and environmentally friendly and reducing pollution.

[0023] As a better alternative, the above is only one method of combined use. Another method is "common heating". A gradient can be set, and under certain conditions, biogas heating is given priority, while circulating hot water heating is used to supplement the heating of the fire wall 13 when the domestic needs are met.

[0024] As a preferred embodiment 3, the firewall 13 is located on the corridor inside the greenhouse 12 and does not occupy the planting area.

[0025] In a preferred embodiment 4, the thermally conductive material is a mixture of clay and sand, with the proportion of clay being greater than the proportion of sand.

[0026] Ensure the thermal conductivity and heat storage capacity of the backfill area 24. When heating begins, ensure a certain thermal conductivity so that the fire wall 13 can dissipate heat outwards but not too quickly or too violently, so as to avoid the temperature inside the greenhouse 12 rising too fast or too high. When heating is stopped, the fire wall 13 can continue to release heat to the greenhouse 12 due to the heat storage capacity of the soil filling area 24 inside the fire wall 13 until the wall temperature cools down to the same temperature as the greenhouse 12.

[0027] like Figure 3 and Figure 6 As shown in the preferred embodiment 5, the fire wall 13 is equipped with an axial flow fan 21 on the side away from the biogas inlet. The water supply pipe 14 passes through the axial flow fan 21 and connects with the return water pipe 15, returning to the hot water storage tank 7 to form a circulation. This ensures the circulation of hot water.

[0028] The combustion chamber 27 is equipped with an exhaust pipe 34 at its end furthest from the biogas inlet. The combustion chamber 27 is connected to the axial flow fan 21 via the exhaust pipe 34, forming an exhaust connection with the outside of the greenhouse 12. This ensures timely removal of combustion products and maintains negative pressure. The combustion chamber 27 is provided with several oxygen channels 26 on both sides. The combustion chamber 27 is connected to the greenhouse 12 outside the fire wall 13 through the oxygen channels 26, and the combustion chamber 27 and the oxygen channels 26 are connected by an axial flow fan 21 to form a negative pressure.

[0029] Under negative pressure, air enters the combustion chamber 27 through the oxygen channel 26 and mixes with biogas, which facilitates complete combustion after being ignited by the biogas ignition device 30. At the same time, the negative pressure guides the direction of the flame to ensure that the flame does not leak out from the fire wall 13.

[0030] The axial flow fan 21 is used to draw in the combustion chamber 27 to create a negative pressure, which is used to promptly draw out the flue gas and products after combustion and discharge them outside the greenhouse 12 to avoid affecting the environment inside the greenhouse 12. At the same time, the negative pressure is created in the combustion chamber 27 so that the flue gas and flame are directed towards the axial flow fan 21, and to prevent the flame in the combustion chamber 27 from leaking out from the oxygen channel 26.

[0031] Preferably, the length of the flame after combustion is controlled by controlling the power of the axial flow fan 21 and the concentration of biogas, so as to ensure that the length of the flame does not directly contact the axial flow fan 21. At the same time, fireproof coating is provided on the axial flow fan 21 and the tail end where it may come into direct contact with the flame.

[0032] The axial flow fan 21 can be a wall-mounted explosion-proof fan.

[0033] like Figure 6 As shown in the preferred embodiment 6, the outlet of the axial flow fan 21 is equipped with a biogas concentration alarm 33. The biogas concentration alarm 33 is used to sense the biogas concentration in the gas at the outlet of the exhaust pipe 34 and issue an alarm when it exceeds the set value. The biogas concentration alarm 33 is linked with the flow valve 19 and the biogas ignition device 30 through the control system 20.

[0034] The biogas concentration alarm 33 is mainly used to detect whether biogas combustion is complete. When the biogas concentration in the combustion product exceeds the standard, an alarm is issued, indicating that the biogas has not been completely burned and there is a certain risk. At this time, the biogas concentration alarm 33 sends a signal to the controller of the control system 20. The controller closes the flow valve 19 and the biogas ignition device 30. After hearing the alarm, the personnel need to reset the flow valve 19 and the axial flow fan 21 and make adjustments to ensure that the combustion is sufficient and complete, and that the biogas concentration in the combustion product is lower than the set value.

[0035] like Figure 5As shown in the preferred embodiment 7, the biogas delivery pipeline 10 is fixedly installed at the bottom of the combustion chamber 27 by a fixed bracket 17. The top of the biogas delivery pipeline 10 is provided with a biogas delivery port 28 that communicates with the combustion chamber 27. A branch valve 29 is provided on the biogas delivery port 28. The biogas ignition device 30 is buried in the backfill area 24 near the biogas delivery port 28. The ignition port 31 of the biogas ignition device 30 extends into the combustion chamber 27 and is close to the end of the biogas delivery port 28 to ignite the biogas.

[0036] The biogas ignition device 30 uses an electric arc igniter. Biogas is delivered to the combustion chamber 27 through the biogas delivery pipeline 10 and enters the combustion chamber 27 through the biogas delivery port 28, where it mixes with the oxygen entering through the oxygen channel 26. After being ignited by the ignition port 31 of the biogas ignition device 30, it is combusted. The branch valve 29 is also a high-temperature resistant electromagnetic valve, used for secondary control of the amount of biogas released. Initially, the branch valve 29 is closed, and the timer in the control system 20 is used to set the time. The time is roughly calculated based on the flow rate and the total length of the biogas delivery pipeline 10 with the branch valve 29. The main purpose of the timer is to make the biogas fill the biogas delivery pipeline 10 as much as possible. The end of the biogas delivery pipeline 10 is sealed, and it is released only through the branch valve 29 and the biogas delivery port 28. When the timer ends, the controller opens the branch valve 29 to release the biogas for ignition.

[0037] like Figure 5 As shown, in a preferred embodiment 8, a flame detector 32 is provided at the top of the combustion chamber 27. The flame detector 32 is used to sense whether there is a flame in the combustion chamber 27. The flame detector 32 is linked with the flow valve 19 and the biogas ignition device 30 through the control system 20.

[0038] The flame detector 32 here uses a flame sensor, which is installed at the interface between the combustion chamber 27 and the oxygen channel 26. It is mainly used to detect whether there is a flame and to assist in detecting the size of the flame. Some flame sensors, such as the HY-A1 model, provide an analog voltage output. The voltage value is inversely proportional to the flame intensity: the stronger the flame, the lower the output voltage. When no flame is detected, it indicates that there is a problem with ignition or that it has not been ignited. The controller of the control system 20 closes the flow valve 19 and the biogas ignition device 30 for maintenance and testing. Based on the approximate intensity of the flame, control the release amount of branch valve 29, and cooperate with flow valve 19 and axial fan 21 to control the flame within the required range. If the flame is too large, gradually reduce the release amount of branch valve 29 and gradually increase the power of axial fan 21 until the flame is within the set range.

[0039] like Figure 6As shown in the preferred embodiment 9, there are multiple combustion chambers 27, which are equally spaced along the fire wall 13. Adjacent combustion chambers 27 are connected and fitted together to form a candied hawthorn shape. Each combustion chamber 27 has an oxygen channel 26 on both sides that corresponds to and is connected to the combustion chamber 27. Each combustion chamber 27 is equipped with a corresponding flame detector 32, a biogas inlet 28, and a biogas ignition device 30.

[0040] like Figure 1 As shown, as a preferred embodiment 10, a rural household energy supply system, used for implementing a rural household energy supply method, includes: The solar power generation module and the public power grid 1 are used for combined power supply. Both the solar power generation module and the public power grid 1 are electrically connected to the transformer 4. The transformer 4 is electrically connected to the air source heat pump 5. The air source heat pump 5 forms a water circulation with the hot water storage tank 7 through a circulation pipeline, and the water in the hot water storage tank 7 is heated by the air source heat pump 5. The hot water storage tank 7 forms a water circulation with the fan coil unit and hot water pipe 8 of the farmer's residential area 9 and the firewall 13 of the greenhouse 12 through two different circulation pipes, and the water in the hot water storage tank 7 exchanges heat with the fan coil unit, hot water pipe 8 and firewall 13 respectively. The biogas generator 11 is connected to the biogas stove in the farmer's residential area 9 and the fire wall 13 in the greenhouse 12 via two different biogas delivery pipes 10. The hot water produced by the biogas stove is connected in parallel to the fan coil and hot water pipe 8 circulation pipeline, and the fire wall 13 ignites the biogas for heating.

[0041] The hot water storage tank 7 is equipped with an electric auxiliary heating component, which is used to assist in heating the water inside when the COP efficiency of the air source heat pump 5 decreases and solar energy is insufficient.

[0042] On sunny days, the solar power generation module drives the air source heat pump 5 to heat the water in the hot water storage tank 7, providing heating for the farmers' residential area 9 and meeting the demand for domestic hot water. At night, the heat stored in the hot water storage tank 7 is used to distribute a portion of the heat energy to the fire wall 13 for auxiliary heating. In extremely cold weather, the COP efficiency of the air source heat pump 5 decreases and solar energy is insufficient. At this time, the electric auxiliary heating in the hot water storage tank 7 is activated to ensure heating for the farmers and the fire wall. Meanwhile, the biogas produced by the manure from the livestock farm 16 is transported to the biogas generator 11, and a small portion of it is used for daily cooking in the farmers' residential area 9 through the biogas transmission pipeline 10. The majority is used for igniting and heating the fire wall 13.

[0043] As a preferred embodiment 11, the solar power generation module includes a distributed photovoltaic system 2 arranged on the roof. After absorbing solar energy, the distributed photovoltaic system 2 is converted into alternating current through a photovoltaic inverter 3 and a transformer 4.

[0044] The distributed photovoltaic system 2 is converted into alternating current by the photovoltaic inverter 3 and transformer 4 for household use. It is connected to the distribution network's service line in a grid-connected manner with self-consumption and surplus power fed into the grid. The distributed photovoltaic system 2 prioritizes supplying power to users. When the power generation of the distributed photovoltaic system 2 is insufficient to meet user demand, the public grid 1 provides supplementary power. When the power generation of the distributed photovoltaic system 2 exceeds user demand, it is also used for heating the greenhouse 12. like Figure 2 As shown, the distributed photovoltaic system 2 is mainly distributed on the roofs of the fattening pens and piglet pens in the farm 16, and is evenly distributed according to the roof area. The weight of a single photovoltaic panel is about 33kg. According to the actual situation of the roof, the roof is reinforced with a fixed steel frame.

[0045] As a preferred embodiment 12, the structures of the circulating pipelines are all the same, each including an independent water supply pipe 14 and a return water pipe 15. Each water supply pipe 14 is equipped with a safety valve 22, and each return water pipe 15 is equipped with a circulating water pump 6.

[0046] Whether it is a heating cycle or a heat supply cycle, as long as it involves a circulation pipeline, the driving force is provided by the circulating water pump 6. After the safety valve 22 is opened, the water circulation is completed under the action of the driving force, along with the circulating water circuit.

[0047] As a preferred embodiment 13, on the farmer's demand side, the circulating water pump 6 delivers hot water through the water supply pipe 14 to the fan coil unit and the hot water pipe 8; The start and stop of the fan coil unit is controlled by the heat load on the user side. When there is heat demand on the farmer side, the fan coil unit is turned on, and when there is no heat demand on the farmer side, the fan coil unit is turned off. On the demand side of greenhouse heating, the circulating water pump 6 delivers hot water through the water supply pipe 14 to the water supply pipe 14 inside the firewall 13; The biogas generator 11 converts the manure and wastewater produced by the livestock farm 16 into biogas and organic fertilizer through anaerobic fermentation. The biogas generator 11 adopts a cylindrical design, and its volume is designed according to the scale of breeding, with 0.33m3 of volume for one pig. The biogas generator 11 uses a polyethylene film or rubber sheet as the tank cover and is equipped with a feeding and discharging system. The feeding pipe is directly connected to the manure discharge outlet of the farm, and the discharging pipe is located at the bottom of the biogas generator. The biogas residue is discharged through the sludge suction pipe and piston device. The biogas produced by the biogas generator 11 is distributed to the fire wall 13 and the biogas stove through the biogas delivery pipeline 10 via the gas distribution cylinder, and a ball valve is installed at the outlet of the gas distribution cylinder to control the biogas flow rate.

[0048] Furthermore, the distributed photovoltaic system 2 uses monocrystalline silicon or polycrystalline silicon photovoltaic modules.

[0049] Furthermore, the photovoltaic inverter 3 is a three-phase grid-connected inverter.

[0050] Furthermore, when the air source heat pump 5 acts as a heat source, it absorbs heat from the outdoor air and releases the heat through the condenser to heat the water flowing to the hot water storage tank 7. The start-up of the air source heat pump 5 is triggered by temperature. Using an existing air source heat pump 5, it starts when the temperature of the hot water storage tank is lower than the set lower limit.

[0051] Furthermore, the starting of the circulating water pump 6 is synchronized with the starting of the air source heat pump 5.

[0052] Furthermore, the hot water storage tank 7 adopts a layered heat storage design.

[0053] Furthermore, the biogas transmission pipeline 10 is made of polyethylene and fitted with a steel pipe.

[0054] Furthermore, the water supply pipe 14 is made of high-temperature and corrosion-resistant stainless steel. Furthermore, the biogas transmission pipeline 10 must be installed in accordance with the principle of "horizontal and vertical" to avoid bending and blockage.

[0055] As a preferred embodiment 14, the rural household energy supply method includes the following steps: Composite power supply: Both the solar power generation module and the public power grid 1 supply power to the air source heat pump 5 through the transformer 4, and the solar power generation module and the public power grid 1 can be switched. The solar power generation module is given priority in power supply, and the public power grid 1 is used for power supply when there is insufficient sunlight. Composite heating: The air source heat pump 5 circulates and heats the water in the hot water storage tank 7. The heated water in the hot water storage tank 7 and the biogas generator 11 both provide heating to the farmers' residential area 9 and the greenhouse 12. The hot water storage tank 7 and the biogas generator 11 can be switched. Gradual heating: Set application scenarios and allocate heating priority between hot water storage tank 7 and biogas generator 11 according to the application scenarios, with hot water storage tank 7 giving priority to supplying heat to farmers' residential areas 9.

[0056] As a preferred embodiment 15, the gradient heating includes the following application scenarios and corresponding gradients: When the ambient temperature is high: the hot water storage tank 7 and the biogas generator 11 give priority to supplying heat to the farmers' residential area 9. Under the premise of meeting the needs of the farmers' residential area 9, the excess heat and biogas are transferred to the greenhouse 12. When the ambient temperature is low: the hot water storage tank 7 prioritizes heating the residential area 9 of farmers. After meeting the needs of the residential area 9, the excess heat is transferred to the greenhouse 12. The biogas generator 11 prioritizes heating the greenhouse 12. After meeting the needs of the greenhouse 12, the excess biogas is transferred to the residential area 9 of farmers.

[0057] As a preferred embodiment 15, the ambient temperature line of the gradient heating is 0℃. When the lowest value of the ambient temperature throughout the day is ≥0℃, the ambient temperature is considered high. When the lowest value of the ambient temperature throughout the day is <0℃, the ambient temperature is considered low.

[0058] As a preferred embodiment 16, it can also be divided into four seasons, with winter being the time when the ambient temperature is low, and spring, summer and autumn being the time when the ambient temperature is high; The main purpose is to maintain the average daily temperature of 16℃ throughout the winter in greenhouses, based on the suitable growth temperature of different crops.

[0059] As a preferred embodiment 17, a specific rural household energy supply method includes the following steps: Step 1: After the distributed photovoltaic system 2 installed on the roof absorbs solar energy, it is converted into alternating current through the photovoltaic inverter 3 and transformer 4 to heat the water in the hot water storage tank 7. The outlet of the hot water storage tank 7 is divided into two branches. At the same time, the manure produced by the livestock farm 16 is collected by a loader and pre-treated. Then it is transferred to the biogas generator 11 through the feed inlet. Fermentation takes place in the biogas generator 11. The biogas residue produced is discharged through the discharge outlet. The generated biogas is divided into two branches. Step Two: The first branch of hot water in the hot water storage tank 7 is connected to the fan coil unit 8 and hot water pipes in the residential area 9 via the water supply pipe 14, meeting the daily heating and domestic hot water needs of the farmers. When heating is required on the user side, the safety valve 22 of the first branch is opened, and the fan in the fan coil unit 8 is started, forcing air to flow through the coil. The cold air is heated into hot air and blown out to heat the room. The water that cools down after releasing heat in the fan coil unit is pumped back to the bottom of the hot water storage tank 7 by the circulating water pump 6 through the return water pipe 15, and then pumped from the hot water storage tank 7 to the air source heat pump 5 by the circulating water pump 6 for reheating and reuse. The second branch is connected directly to the water supply pipe inside the firewall 13 via the water supply pipe 14. The heat of the hot water in the supply pipe is continuously and evenly dissipated to the firewall 13 in the form of radiation and convection. After flowing through the firewall 13 and cooling down, the water is pumped back to the bottom of the hot water storage tank 7 by the circulating water pump 6 via the return water pipe 15, and then pumped from the hot water storage tank 7 to the air source heat pump 5 for heating by the circulating water pump 6. Meanwhile, the first branch of biogas in the biogas digester 11 is delivered to the biogas stove in the kitchen via a gas guide pipe and a polyethylene conveying pipe with a steel outer casing 10, for the daily cooking of farmers; the second branch is delivered to the fire wall 13 via the conveying pipe 10. Biogas enters the biogas conveying pipe 10 inside the fire wall 13 through the flow valve 19. After the biogas fills the entire conveying pipe 10, the branch valve of each combustion chamber is opened, and the biogas combustion device and axial flow fan 21 are started at the same time. The biogas concentration monitoring system 18 monitors the biogas concentration in real time and transmits the monitoring data to the control system 20. The control system 20 adjusts the size of the flow valve 19 and the wind force of the axial flow fan 21 according to the input data to achieve safe and complete combustion of biogas.

[0060] Step 3: The solar-powered air source heat pump 5 heats water and stores it in the hot water storage tank 7. The hot water supply prioritizes meeting the heating needs of farmers, and secondly enhances the heating effect of the fire wall 13. When the COP efficiency of the heat pump decreases and solar energy is insufficient, the electric auxiliary heating in the hot water storage tank 7 is activated to still prioritize the heating of farmers. Biogas is used as a combustion source to heat the fire wall 13. In winter, when the night is cold or in extremely cold conditions, it prioritizes meeting the heating needs of the greenhouse 12. In other climatic situations, it prioritizes meeting the cooking needs of farmers.

Claims

1. A method for providing energy supply in rural households, characterized by, The method comprises the following steps: Composite power supply: the solar power module and the public power grid (1) both supply power to the air source heat pump (5) through the transformer (4), and the solar power module and the public power grid (1) can be switched, and the solar power module is preferentially used for power supply, and the public power grid (1) is used for power supply when sunlight is insufficient; Composite heating: the air source heat pump (5) circulates and heats the water in the heat storage water tank (7), and the heated water in the heat storage water tank (7) and the biogas generating tank (11) both supply heat to the farmer residential area (9) and the greenhouse (12), and the heat storage water tank (7) and the biogas generating tank (11) can be switched; Gradient heating: setting application scenarios, and sequentially distributing the heating priority of the heat storage water tank (7) and the biogas generating tank (11) according to the application scenarios, and the heat storage water tank (7) preferentially supplies heat to the farmer residential area (9).

2. The rural household energy supply method according to claim 1, characterized in that, The gradient heating comprises the following application scenarios and corresponding gradients: When the environmental temperature is relatively high: the heat storage water tank (7) and the biogas generating tank (11) both preferentially supply heat to the farmer residential area (9), and under the premise of meeting the use of the farmer residential area (9), the excess heat and biogas are transported to the greenhouse (12); When the environmental temperature is relatively low: the heat storage water tank (7) preferentially supplies heat to the farmer residential area (9), and under the premise of meeting the use of the farmer residential area (9), the excess heat is transported to the greenhouse (12), and the biogas generating tank (11) preferentially supplies heat to the greenhouse (12), and under the premise of meeting the use of the greenhouse (12), the excess biogas is transported to the farmer residential area (9).

3. The rural household energy supply method according to claim 2, characterized in that, The environmental temperature line of the gradient heating is 0℃, when the all-day minimum value of the environmental temperature is greater than or equal to 0℃, it is considered that the environmental temperature is relatively high, and when the all-day minimum value of the environmental temperature is less than 0℃, it is considered that the environmental temperature is relatively low.

4. A rural household energy supply system, characterized in that For the implementation of the rural household energy supply method as claimed in any one of claims 1-3, comprising: A solar power module and a public power grid (1) for composite power supply, the solar power module and the public power grid (1) are both electrically connected with a transformer (4), and the transformer (4) is electrically connected with an air source heat pump (5); The air source heat pump (5) forms water circulation with a heat storage water tank (7) through a circulation pipeline, and the water in the heat storage water tank (7) is circulated and heated by the air source heat pump (5); The heat storage water tank (7) forms water circulation with a fan-coil and a hot water pipeline (8) of a farmer residential area (9) and a firewall (13) of a greenhouse (12) through two different circulation pipelines, and the water in the heat storage water tank (7) forms heat exchange with the fan-coil and the hot water pipeline (8) and the firewall (13) respectively; The biogas generating tank (11) is connected with a biogas stove of the farmer residential area (9) and the firewall (13) of the greenhouse (12) through two different biogas pipelines (10), and the hot water generated by the biogas stove is connected in parallel to the circulation pipeline of the fan-coil and the hot water pipeline (8), and the firewall (13) ignites biogas for heating.

5. The rural household energy supply system according to claim 4, characterized in that The solar power module comprises a distributed photovoltaic system (2) arranged on a roof, which converts solar energy into alternating current through a photovoltaic inverter (3) and a transformer (4).

6. The rural household energy supply system according to claim 4, characterized in that The circulating pipeline has the same structure and comprises a water supply pipe (14) and a return water pipe (15) which are independent of each other.

7. A firewall, characterized by The composition of the rural household energy supply system as claimed in any one of claims 4-6, which supplies heat to the greenhouse (12), comprises: The hollow wall (13) is formed by stacking brick walls (25) in the vertical direction, and the wall (13) is filled with a heat-conducting material in the filling area (24), and the filling area (24) is provided with a flow-through hole (23) and a combustion chamber (27) which penetrate the wall (13) along the extension direction of the wall body; The flow-through hole (23) is provided with a water supply pipe (14), and the water supply pipe (14) is in heat conduction with the filling area (24), and the inlet of the water supply pipe (14) is connected with the outlet of the heat storage water tank (7); The combustion chamber (27) is provided with a biogas delivery pipeline (10) and a biogas ignition device (30), the inlet of the biogas delivery pipeline (10) is connected with the biogas generation tank (11), and the biogas delivery pipeline (10) is sequentially provided with a biogas concentration monitoring system (18) and a flow valve (19) along the biogas delivery direction, and the biogas generation tank (11) provides biogas to the combustion chamber (27) through the biogas delivery pipeline (10), which is ignited by the biogas ignition device (30) to provide heat by combustion; The wall (13) is provided with a control system (20) including at least a controller on one side, and the biogas concentration monitoring system (18), the flow valve (19), the biogas ignition device (30), the safety valve (22) of the circulating pipeline between the wall (13) and the heat storage water tank (7), and the circulating water pump (6) are all electrically connected with the control system (20).

8. The firewall of claim 7, wherein, The wall (13) is provided with an axial flow fan (21) on the side away from the biogas inlet end, the water supply pipe (14) passes through the axial flow fan (21) and is connected with the return water pipe (15) to form a circulation back to the heat storage water tank (7); The combustion chamber (27) is provided with an exhaust pipeline (34) at the end away from the biogas inlet end, and the combustion chamber (27) is connected with the axial flow fan (21) through the exhaust pipeline (34) and forms an air outlet cooperation with the outside of the greenhouse (12); The combustion chamber (27) is provided with a plurality of oxygen channels (26) on both sides, and the combustion chamber (27) is connected with the inside of the greenhouse (12) outside the wall (13) through the oxygen channels (26), and the combustion chamber (27) and the oxygen channels (26) form a negative pressure inside through the axial flow fan (21).

9. The firewall of claim 8, wherein, The axial flow fan (21) air outlet is provided with a biogas concentration alarm (33), the biogas concentration alarm (33) is used to induct the biogas concentration in the air outlet end gas of the air extraction pipeline (34) and sends out the alarm when exceeding the set value, the biogas concentration alarm (33) is linked with the flow valve (19) and the biogas ignition device (30) by the control system (20).

10. The firewall of claim 7, wherein, The biogas conveying pipeline (10) is fixedly installed on the bottom in the combustion chamber (27) by the fixing support (17), the top of the biogas conveying pipeline (10) is provided with a biogas conveying port (28) and is communicated with the combustion chamber (27), the branch valve (29) is arranged on the biogas conveying port (28), the biogas ignition device (30) is buried in the filling area (24) near the side of the biogas conveying port (28), the ignition port (31) of the biogas ignition device (30) is inserted into the combustion chamber (27) and is close to the end of the biogas conveying port (28) for igniting the biogas.

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