A heating system for biogas production area and living area

Abstract

A heating system for a biogas production area and a living area, characterized in that it includes a heating main pipe, on which an independent production heating system and a living heating system are connected in parallel, and an opening and closing valve is provided at the inlet end of the living heating system; a high-temperature air source heat pump unit and a gas hot water boiler are respectively connected to the heating main pipe for heating; and valves for switching heat sources according to seasonal changes are respectively provided on the supply and return pipes of the high-temperature air source heat pump unit and the gas hot water boiler. The heating system for a biogas production area and a living area of ​​the present invention adopts a high-temperature air source heat pump unit and a gas hot water boiler as heat sources for coordinated operation. A high-temperature air source heat pump unit or a gas hot water boiler is selected for heating according to the outdoor meteorological temperature to minimize energy consumption.

Description

Technical Field

[0001] The invention relates to a production and living heating system for a biogas engineering project. Background Art

[0002] Biogas is a green, low-carbon, clean and renewable natural gas produced by anaerobic fermentation and purification of various urban and rural organic wastes such as crop straw, livestock and poultry manure, kitchen waste, and wastewater from agricultural and sideline products processing. At the same time, the biogas residue and liquid produced during anaerobic fermentation can be used to produce organic fertilizer. In the process of biogas production, many production projects are involved. Among many production projects, fermentation projects in particular require a large amount of heat energy for material fermentation. The biogas production area and living area are heated by boiler heating systems to ensure the heating needs of production and life. The current biogas project production process mostly uses boilers as heat sources for heating, which usually have low energy utilization and high heating energy consumption. In order to respond to the call for energy conservation and emission reduction and reduce production and operation costs, it is urgent to develop a new heating system suitable for biogas production and living areas, which can reduce energy consumption and improve energy utilization efficiency while meeting the daily production and living heating needs of the factory area. Summary of the invention

[0003] The purpose of the present invention is to provide an efficient heating system for biogas production and living areas, which can select heat sources with different energy consumption for heating according to the outdoor weather temperature. Through the coordinated operation of the heat sources, the energy consumption can be reduced to the maximum extent while meeting the heating requirements of the production and living areas.

[0004] To achieve the above-mentioned purpose, the technical solution provided by the present invention is a high-efficiency heating system for a biogas production area and a living area, characterized in that it includes a heating main pipe, on which an independent production area heating system and a living area heating system are connected in parallel, and on-off valves are provided on the supply and return pipes of the living area heating system; a high-temperature air source heat pump unit and a gas-fired hot water boiler are respectively connected to the heating main pipe for heating; and valves for switching heat sources according to seasonal changes are respectively provided on the inlet and outlet pipes of the high-temperature air source heat pump unit and the gas-fired hot water boiler.

[0005] A water replenishment constant pressure device is arranged on the hot water supply pipe of the heating main pipe and in front of the inlet end of the heating circulation pump of the production heating system and the living area heating system.

[0006] Regulating valves are respectively provided on the supply and return pipes of the production area heating system and the living area heating system; the regulating valve of the production area heating system is adjusted according to the temperature parameters of the fermentation tank, and the regulating valve of the living area heating system is connected to the climate compensator and adjusted according to the outdoor temperature information.

[0007] The heating systems of the various fermentation tanks in the production area are connected in parallel.

[0008] Thermal inlet devices are provided on the water supply and return pipes of each fermentation tank heating system.

[0009] The fermentation tank heating system comprises a fermentation tank outer wall heating system, a fermentation tank internal heating system and a fermentation tank tank bottom heating system.

[0010] The fermentation tank outer wall heating system includes a water distribution mother pipe and a water collection mother pipe arranged on one side of the outer periphery of the fermentation tank wall; the water distribution mother pipe and the water collection mother pipe are connected by several annular heating pipes arranged at horizontal intervals; the lower end of the water distribution mother pipe is connected to the hot water supply pipe at the thermal inlet device; the lower end of the water collection mother pipe is connected to the return water pipe at the thermal inlet device; and an insulation layer is arranged outside the water distribution mother pipe, the water collection mother pipe and the interlayer between the heating pipe.

[0011] Automatic exhaust valves are respectively arranged at the upper ends of the water distribution mother pipe and the water collection mother pipe.

[0012] The heating system in the fermentation tank includes a water supply main pipe and a return water main pipe horizontally arranged around the inner wall in a same-length manner at the upper and lower ends of the inner wall of the fermentation tank, the water supply main pipe is located at the lower end of the inner wall, and the return water main pipe is located at the upper end of the inner wall; the water supply main pipe and the return water main pipe are connected by a plurality of parallel and spaced vertical heating branch pipes; the water inlet end of the water supply main pipe is connected to the hot water supply pipe at the thermal inlet device, and the water outlet end of the return water main pipe is connected to the return water pipe at the thermal inlet device.

[0013] An automatic exhaust valve is arranged at the highest point of the return water main pipe.

[0014] The fermentation tank bottom heating system is a multi-layer structure, which includes a surface layer, a pebble concrete layer, a heating coil layer, an insulation layer, and a waterproof layer from top to bottom; the water inlet end of the heating coil layer is connected to a water distribution pipe in a distributor located outside the fermentation tank, and the water outlet end is connected to a water collection pipe in the distributor; the water distribution pipe is connected to a hot water supply pipe at a thermal inlet device, and the water collection pipe is connected to a return pipe at the thermal inlet device.

[0015] The surface layer is a corrosion-resistant metal plate.

[0016] A metal mesh layer for fixing the heating coil is also arranged between the heating coil layer and the insulation layer.

[0017] The heating coil comprises a plurality of heating loops; the water inlet end of each heating loop is connected with the water distribution pipe, and the water outlet end is connected with the water collection pipe.

[0018] When the top of the fermentation tank is a double-layer air film, a heat-insulating layer is arranged between the double-layer air film.

[0019] The heating system for the biogas production area and living area of ​​the present invention adopts a high-temperature air source heat pump unit and a gas hot water boiler as heat sources for coordinated operation. A high-temperature air source heat pump unit or a gas hot water boiler is selected as the heat source according to different seasons to minimize energy consumption.

[0020] When the project area is located in a severely cold or cold region, the gas hot water boiler is started in winter to heat the system, and the high-temperature air source heat pump unit is stopped; in the transition season and summer, the gas boiler is stopped, and the high-temperature air source heat pump unit is started. Since the heating performance coefficient of the air source heat pump unit under nominal conditions can be as high as 3 or more, which is much less than the energy consumption of the gas boiler, this coordinated operation system will greatly reduce the energy consumption of the system and has good energy saving and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 , a schematic diagram of the structure of the heating system of the present invention.

[0022] Figure 2 , schematic diagram of the expanded structure of the fermentation tank peripheral heating system.

[0023] Figure 3 , schematic diagram of the expanded structure of the heating system in the fermenter.

[0024] Figure 4 , schematic diagram of the fermentation tank bottom heating system.

[0025] Figure 5 , Schematic diagram of the heating coil layer structure at the bottom of the fermentation tank.

[0026] Figure 6 , schematic diagram of the water supply end and return water end of the heating coil in the fermentation tank bottom heating system and the water distribution pipe and collecting pipe structure in the distributor. In the figure, the solid line is the water supply end and the dotted line is the return water end.

[0027] Figure 7 , Figure 6 Schematic diagram of the structure in direction A, in the figure, the solid line is the water supply end and the dotted line is the return water end. DETAILED DESCRIPTION

[0028] With respect to the above technical solution, preferred embodiments are now given for specific description in conjunction with drawings.

[0029] Heating main 1, see Figure 1, including a hot water supply pipe and a return pipe. The heat supply main is connected to the air source heat pump unit 2 and the gas hot water boiler 3 through pipes. A switching valve 201 is provided on the pipes connecting the air source heat pump unit 2 and the gas hot water boiler 3 to the heat supply main, respectively, for controlling the switching between the air source heat pump unit 2 and the gas hot water boiler 3. The other end of the heat supply main is connected to the living area heating system 4 and the production area heating system 5 through pipes. Figure 1 In the figure, the solid line represents the hot water supply pipe and the dotted line represents the return pipe.

[0030] A high-temperature air source heat pump unit and a gas hot water boiler are used in a coordinated operation system to provide 55℃~60℃ hot water for living and production, ensuring the heating requirements for the factory's domestic heating and fermentation system.

[0031] When the project is located in a severely cold or cold region, the gas hot water boiler is started in winter to heat the system, and the air source heat pump unit is stopped; in the transition season and summer, the gas boiler is stopped, and the high-temperature air source heat pump unit is started. Since the heating performance coefficient of the air source heat pump unit under nominal conditions can be as high as 3 or more, which is much less than the energy consumption of the gas boiler, this coordinated operation system will greatly reduce the energy consumption of the system and has good energy saving and economy.

[0032] When the project is located in the hot summer and cold winter, hot summer and warm winter, and mild climate zones, the gas hot water boiler system can be omitted, and only the high-temperature air source heat pump unit can be used to meet the corresponding heating requirements and achieve a greater degree of energy saving.

[0033] The heat source adopts a coordinated operation system of a high-temperature air source heat pump unit and a gas hot water boiler. In areas with high outdoor temperatures or in seasons with high temperatures, the system heating can be achieved only by the high-temperature air source heat pump unit with high energy utilization efficiency, avoiding the use of a gas boiler system with low energy utilization rate for heating. The entire heating system reduces energy consumption, improves energy utilization and the economy of the project.

[0034] A water replenishment constant pressure device 101 and a softened water treatment device 102 are provided on the hot water supply pipe of the heating main, and the softened water treatment device is connected to the tap water pipe. The water replenishment constant pressure device needs to be located in front of the inlet end of the heating circulation pump of the production heating system and the living area heating system, and the pressure of the heating system is maintained stable by the water replenishment constant pressure device.

[0035] An on-off valve 401 and a regulating valve 402 are sequentially arranged on one end of the pipe connecting the living area heating system 4 and the heating main. The on-off valve 401 is arranged on the hot water pipe and the return pipe of the living area heating system to control the opening and closing of the living area heating system. The regulating valve 402 is arranged between the hot water pipe and the return pipe. A climate compensator 403 is connected to the regulating valve 402, and the climate compensator is connected to a temperature sensor 404 located outdoors. The climate compensator controls the heating bypass flow rate by adjusting the size of the regulating valve 402 according to the outdoor temperature to ensure the reasonable and stable temperature of the living area. A heating circulation pump and related valves 405 are arranged on the hot water supply pipe to provide circulation power for the living area heating system. When heating of the living area is not needed, the valve 401 can be closed to cut off the heating of the living area.

[0036] A regulating valve 501 and related opening and closing valves are sequentially arranged on one end of the pipe connecting the production area heating system 5 with the heating main. The regulating valve is arranged between the hot water supply pipe and the return pipe. The regulating valve adjusts the heating flow rate according to the temperature information of the fermenter. A process heating circulation pump and related valves 502 are arranged on the hot water supply pipe to provide circulation power for the production area heating system. The heating systems of each fermenter 6 in the production area are respectively connected with the production area heating system. A thermal inlet device 503 is arranged at the inlet end of each fermenter heating system. By arranging a thermal inlet device with a self-powered flow control valve, the thermal inlet device is connected with each heating system of the fermenter through the hot water pipe and the return pipe to provide heat for it, ensuring the hot water flow rate required by each fermenter, and realizing the heat supply regulation of each tank body by adjusting the water supply temperature.

[0037] A heating circulation pump power system, heat regulating devices between each monomer and fermentation tank body, and an outdoor heating pipe network system are used. This method is different from the traditional practice of setting up each fermentation tank and the circulation power system one by one in the biogas industry. Instead, it sets a thermal inlet device with a self-powered flow control valve to ensure the hot water flow required by each fermentation tank, and adjusts the water supply temperature to achieve heat regulation of each tank body. This pipe network setting method greatly reduces the number of equipment and pipe networks in commonly used heating systems, including hot water circulation pumps and outdoor heating pipe networks, thereby alleviating the large amount of land occupied by the laying of outdoor heating pipe networks, reducing initial investment, and also reducing the problem of interlacing with other professional outdoor pipelines.

[0038] The fermentation tank heating system includes the fermentation tank outer wall heating system, the fermentation tank internal heating system, and the fermentation tank bottom heating system. The production area heating system provides heat to each heating system of the fermentation tank.

[0039] Peripheral heating system for fermenters, see Figure 2The material of the fermentation tank wall is ceramic or metal, and a water-distributing mother pipe 601 and a water-collecting mother pipe 602 are vertically arranged on one side of the outer circumference thereof, and several parallel annular heating pipes 603 arranged around the outer wall of the fermentation tank are connected between the water-distributing mother pipe and the water-collecting mother pipe. The lower end of the water-distributing mother pipe is connected to the hot water supply pipe at the thermal inlet device to provide hot water for it. The lower end of the water-collecting mother pipe is connected to the return pipe at the thermal inlet device. Automatic exhaust valves 604 are respectively arranged at the upper ends of the water-distributing mother pipe and the water-collecting mother pipe. A layer of insulation layer 605 is coated on the outer periphery of the interlayer of the heating system outside the fermentation tank for insulation. The amount of heat supplied to the tank body is adjusted by adjusting the supply and return water temperatures and the spacing between the heating pipes. Since the heating pipe does not contact the fermentation material, relatively low-priced oxygen-blocking plastic pipes can be used. The service life of this material can reach 50 years, and the cost is relatively low.

[0040] The top of the fermentation tank is provided with an inner film 606 and an outer film 607 for storing biogas. A flexible thermal insulation layer 608 is provided between the inner film and the outer film. The flexible thermal insulation material requires a material with a small bulk density, good flexibility, and a small thermal conductivity coefficient, such as commonly used closed-cell rubber and plastic materials, which can achieve good thermal insulation performance and greatly reduce the heat dissipation of the tank top.

[0041] As the carrier of the fermentation system, the temperature inside the fermentation tank is required to be maintained at the required fermentation temperature all year round, which is higher than the outdoor air temperature for a long time. Therefore, the enclosure structure of the tank wall, tank bottom and tank top become the heat dissipation source. It is easier to set up an insulation system in a hard-top fermentation tank, but there is often no insulation layer on the top membrane of a soft-top fermentation tank. Through the calculation and analysis of the heat dissipation of each heat source of the entire fermentation tank, the heat dissipation of the membrane tank roof without an insulation layer can account for more than 70% of the heat dissipation of the entire fermentation tank body. Therefore, adding insulation measures on the tank top has important energy-saving and economic significance.

[0042] Heating system in fermenter, see Figure 3 At the upper and lower ends of the inner wall of the fermentation tank, a water supply main pipe 701 and a return water main pipe 702 are arranged horizontally around the inner wall in a same-path manner. The water supply main pipe is located at the lower end of the inner wall, and the return water main pipe is located at the upper end of the inner wall. The water supply main pipe and the return water main pipe are connected by several parallel vertical heating branches 703. An automatic exhaust valve (not shown) is arranged at the highest point of the heating system in the fermentation tank, that is, the return water main pipe, to ensure the fermentation temperature required by the fermentation material. The water inlet end of the water supply main pipe is connected to the hot water supply pipe at the thermal inlet device to provide hot water for it. The water outlet end of the return water main pipe is connected to the return water pipe at the thermal inlet device through a pipeline. The amount of heat supply is adjusted by adjusting the supply and return water temperatures and the spacing between the heating pipes. Since the heating system in the pipe needs to contact the fermentation material, the pipe material of the heating system needs to be corrosion-resistant. At the same time, the pressure-bearing strength of the pipe meets the pressure requirements of the heating system, and the normal service life is not less than 30 years.

[0043] Since the temperature gradient distribution of the liquid in the tank itself is a decreasing process from top to bottom, and it is an objective law. The heating system in the fermentation tank of the present invention is a bottom-in and top-out heating method, and the high-temperature hot water is mainly located in the lower area of ​​the tank, which is more beneficial to the uniform temperature of the lower and upper parts of the tank. The same-program system layout has good hydraulic balance, which is more beneficial to the uniform temperature of a circle in the tank. At the same time, the vertical heating branch pipe is less likely to cause the solid matter in the tank to deposit on the heating pipe than the horizontal heating branch pipe, which is more beneficial to heat dissipation. This heating method can better achieve uniform temperature distribution in the tank, achieve good fermentation temperature requirements, and improve fermentation efficiency. The amount of heat supply can be adjusted by adjusting the spacing of the vertical heating branches to adjust the heat dissipation area, thereby realizing the adjustment of the heat supply to the tank body.

[0044] The fermentation tank bottom heating system is a multi-layer structure. Figures 4 to 7 It includes a surface layer (with waterproof function) 801, a pebble concrete layer 802, a heating coil layer 803, a wire mesh layer 804, an insulation layer (including a protective layer) 805, a waterproof layer 806, and a structural plate layer 807, a total of 7 layers from top to bottom.

[0045] The surface layer 801 is made of corrosion-resistant metal plates, which have good thermal conductivity, enhance the heat dissipation effect of the ground, and also have good waterproof effect; the pebble concrete layer 802 is mainly used as a protective layer for the heating coil, and the pebble particle size is 5mm to 12mm, the concrete strength is not less than C15, and the thickness is determined by the ground load; the heating coil can use relatively low-priced plastic pipes, such as PE-X pipes, PB pipes, or copper pipes. The heating coil layer is arranged at the bottom of the pebble concrete layer, and the insulation layer 805 selects a composite insulation layer with an aluminum foil protective layer, which is also conducive to upward heat reflection.

[0046] The heating coil 803 is laid in a circular ring shape at the bottom of the tank from the center of the tank bottom to the outer wall of the tank. The heating coil is composed of multiple loops according to the heat supply situation. The water supply end of each loop is connected to the water distributor 810 in the distributor 809 located outside the fermenter, and the other end of the water distributor 810 is connected to the hot water supply pipe at the thermal inlet device; the return water end is connected to the water collector 811 in the distributor 809 located outside the fermenter, and the water collector is connected to the return water pipe at the thermal inlet device. Automatic exhaust valves 812 are respectively provided on the water distributor and the water collector. By arranging multiple heating loops at the bottom of the tank, and the lengths of each loop are comparable, hydraulic balance between each loop can be ensured, and the heat supply of each loop can be guaranteed. The heating coils are evenly spread over the bottom of the fermenter to heat the bottom of the fermenter, and the heat supply can be adjusted by adjusting the spacing of the heating coils. The wire mesh layer can be set as an option to better fix the heating pipe, especially when the heating pipe is a heating cable; when the wire mesh is set, the heating pipe is fixed by a cable tie. The insulation layer is mainly used to reduce heat loss to the ground. Foamed cement or EPS insulation board can be used; the waterproof layer is mainly to prevent the liquid in the tank from seeping and its impact on the structural foundation; the structural plate is a concrete bottom plate to meet the normal operation of the tank load.

[0047] The fermentation tank heating system of the present invention heats the tank from the inside or outside, the tank top, and the tank bottom in all directions. An insulation layer is added between the inner and outer membranes of the tank top to reduce the heat dissipation. The temperature of each part in the fermentation tank is ensured to be uniform through the design of the heating terminal system, thereby improving the fermentation efficiency and the heat utilization rate. At the same time, the high-temperature air source heat pump unit and the gas hot water boiler coordinate the operation system to minimize energy consumption and reduce production costs.

Claims

1. A heating system for biogas production area and living area, characterized in that It comprises a heat supply main pipe, on which an independent production heating system and a living area heating system are connected in parallel, and an opening and closing valve is arranged at the inlet end of the living area heating system; a high-temperature air source heat pump unit and a gas hot water boiler are respectively connected to the heat supply main pipe; valves for switching heat sources according to outdoor meteorological temperatures are respectively arranged on the inlet and outlet pipes of the high-temperature air source heat pump unit and the gas hot water boiler; Each fermentation tank heating system in the production area is connected in parallel with the production area heating system, and a thermal inlet device is provided on the water inlet and outlet pipes of each fermentation tank heating system. The fermentation tank heating system includes a fermentation tank outer wall heating system, a fermentation tank internal heating system, and a fermentation tank tank bottom heating system; Among them, the heating system in the fermentation tank includes a water supply main pipe and a return water main pipe horizontally arranged around the inner wall in a same-length manner at the upper and lower ends of the inner wall of the fermentation tank, the water supply main pipe is located at the lower end of the inner wall, and the return water main pipe is located at the upper end of the inner wall; the water supply main pipe and the return water main pipe are connected by a number of parallel and spaced vertical heating branch pipes; the water inlet end of the water supply main pipe is connected to the hot water supply pipe at the thermal inlet device, and the water outlet end of the return water main pipe is connected to the return water pipe at the thermal inlet device through a pipeline; and an automatic exhaust valve is provided at the high point of the return water main pipe.

2. The heating system for the biogas production area and living area according to claim 1 is characterized in that A water replenishment constant pressure device is arranged on the hot water supply pipe of the heating main pipe and in front of the inlet end of the heating circulation pump of the production heating system and the living area heating system.

3. The heating system for the biogas production area and living area according to claim 1 is characterized in that Regulating valves are respectively provided at the inlet ends of the production area heating system and the living area heating system; the regulating valve of the production area heating system is adjusted according to the temperature parameters of the fermentation tank, and the regulating valve of the living area heating system is connected to the climate compensator and adjusted according to the outdoor temperature information.

4. The heating system for the biogas production area and living area according to claim 1 is characterized in that The fermentation tank outer wall heating system includes a water distribution mother pipe and a water collection mother pipe arranged on one side of the outer periphery of the fermentation tank wall; the water distribution mother pipe and the water collection mother pipe are connected by several annular heating pipes arranged at horizontal intervals; the lower end of the water distribution mother pipe is connected to the hot water supply pipe at the thermal inlet device; the lower end of the water collection mother pipe is connected to the return pipe at the thermal inlet device; and an insulation layer is arranged outside the water distribution mother pipe, the water collection mother pipe and the heating pipe interlayer.

5. The heating system for the biogas production area and living area according to claim 4 is characterized in that Automatic exhaust valves are respectively arranged at the upper ends of the water distribution mother pipe and the water collection mother pipe.

6. The heating system for biogas production area and living area according to claim 1 is characterized in that The fermentation tank bottom heating system is a multi-layer structure, which includes a surface layer, a pebble concrete layer, a heating coil layer, an insulation layer, and a waterproof layer from top to bottom; the water inlet end of the heating coil layer is connected to a water distribution pipe in a distributor located outside the fermentation tank, and the water outlet end is connected to a water collection pipe in the distributor; the water distribution pipe is connected to a hot water supply pipe at a thermal inlet device, and the water collection pipe is connected to a return pipe at the thermal inlet device.

7. The heating system for the biogas production area and living area according to claim 6 is characterized in that The surface layer is a corrosion-resistant metal plate.

8. The heating system for the biogas production area and living area according to claim 6 is characterized in that A metal mesh layer for fixing the heating coil is also arranged between the heating coil layer and the insulation layer.

9. The heating system for the biogas production area and living area according to claim 6, characterized in that The heating coil comprises a plurality of heating loops; the water inlet end of each heating loop is connected with the water distribution pipe, and the water outlet end is connected with the water collection pipe.

10. The heating system for biogas production area and living area according to any one of claims 4 to 8, characterized in that When the top of the fermentation tank is a double-layer air film, a heat-insulating layer is arranged between the double-layer air film.

Images