System and method for solar photo-thermal-biomass gasification combined heating and poly-generation of soil conditioner and tree protection material

Abstract

The invention belongs to the technical field of comprehensive utilization of renewable energy sources and resource utilization of agricultural and forestry wastes, and provides a system and a method for solar photo-thermal-biomass gasification combined heating and poly-generation of a soil conditioner and a tree protection material. The system comprises a solar photo-thermal subsystem, a biomass fixed bed gasification and heating subsystem, a synthesis gas cooling purification and gas-fired boiler heating unit, a building heating loop and waste heat recovery unit, a by-product collection and resource utilization subsystem and a CO sensing and safety control subsystem. Biomass is gasified in a fixed bed gasification furnace to generate high-temperature synthesis gas and plant ash carbon, the high-temperature synthesis gas is subjected to multi-stage cooling and purification and then serves as fuel of a gas-fired boiler for heating, and meanwhile waste heat in the gasification process and the combustion process is recycled through a synthesis gas cooler, a furnace body water jacket and a boiler flue gas heat exchanger; wood vinegar and tar are obtained through oil-water separation of the condensate, the wood vinegar is used for soil improvement and plant growth conditioning, and the tar is used for tree insect prevention, corrosion prevention and wound sealing; the plant ash carbon is cooled, crushed and screened to be applied to farmland or garden plots as a soil conditioner. According to the system, CO sensors are arranged in an equipment room and a living space, and are interlocked with a fan, an electromagnetic valve and combustion control through a controller, so that graded early warning and emergency furnace shutdown when the CO concentration exceeds the standard are realized, and CO poisoning is effectively prevented. According to the invention, solar energy and biomass heat source complementation, efficient heating and poly-generation integration of soil improvement and plant protection are realized, and the system is suitable for popularization and application in rural residences, greenhouses and small public buildings.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive utilization of renewable energy and resource utilization of agricultural and forestry waste, and relates to a system and method for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Currently, utilizing renewable energy sources such as solar energy and biomass to replace traditional fossil fuels has become an important direction for the development of building heating and rural energy systems. Solar thermal heating technology collects solar radiation through collectors and converts it into heat energy for indoor heating or domestic hot water, offering advantages such as being clean and renewable. However, solar radiation exhibits significant diurnal and seasonal variations, making it difficult for a single solar thermal system to stably meet heating loads during cloudy or rainy weather or at night. This typically requires supplementary coal-fired, gas-fired, or electric boilers, resulting in higher energy costs or higher carbon emissions.

[0004] Biomass fixed-bed gasification technology utilizes agricultural and forestry waste such as straw, tree branches, and fruit tree pruning materials, undergoing pyrolysis and gasification under an oxygen-deficient or quasi-reducing atmosphere. This produces combustible gases (mainly CO, H2, CH4, etc.), solid char, and a small amount of ash, along with byproducts such as tar and condensate (wood vinegar). The syngas obtained from biomass gasification can be used in gas-fired boilers or gas-fired engines to achieve clean heating or power generation. However, existing small-scale gasification heating devices primarily focus on "gas production for heating," neglecting the resource utilization of byproducts such as wood ash, charcoal, wood vinegar, and tar, often treating them as waste, resulting in resource waste.

[0005] On the other hand, during the operation of a biomass gasification system, if the gas path is poorly sealed or combustion is incomplete, CO leakage can easily occur. CO is a colorless, odorless, and highly toxic gas, and when it accumulates in relatively enclosed spaces such as rural houses or small machine rooms, it can easily cause poisoning accidents. Existing small stoves or biomass boilers are usually only equipped with simple ventilation facilities or independent CO alarms, lacking a linkage mechanism with fans, valves, and combustion controls, resulting in limited safety protection levels.

[0006] Wood ash and wood charcoal can be used as important soil conditioners to increase soil organic carbon content, improve soil aggregate structure, and enhance water and fertilizer retention capacity. Wood vinegar, after proper dilution, can be used as a soil conditioner or plant growth regulator, and has a positive effect on soil microbial communities and plant root growth. Tar, after proper treatment, can be applied to tree trunks or pruning wounds to prevent insects, prevent decay, and seal wounds, and is suitable for the protection of fruit trees and garden trees.

[0007] A study has disclosed a combined solar and biomass energy heating system, which includes a heat collection module, a heat storage module, a heat exchange module, a power unit, a biomass heat supplement module, and a heating / heating space. However, its energy utilization rate and resource recovery rate still need to be improved. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides a system and method for combined solar thermal and biomass gasification heating, as well as the production of multi-product soil conditioners and tree protection materials. This invention utilizes the complementary heat sources of solar energy and biomass gasification, employing gasified gas to drive a gas-fired boiler for heating while simultaneously recovering waste heat from each stage of the gasification process. Furthermore, it involves the graded collection and resource utilization of wood ash, wood vinegar, and tar, coupled with multi-point CO sensing and interlocking safety control, to achieve synergistic integration of heating, soil improvement, and tree protection.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a system for combined solar thermal and biomass gasification heating and multi-product soil conditioner and tree protection material, comprising: a solar thermal subsystem, a biomass gasification and heating subsystem, a syngas cooling, purification and gas boiler heating unit, a building heating circuit and waste heat recovery unit, a by-product collection and resource utilization subsystem, and a CO sensing and safety control subsystem. The solar thermal subsystem, biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit are respectively connected to the building heating circuit and waste heat recovery unit. The condensate outlet of the syngas cooling, purification and gas boiler heating unit is also connected to the by-product collection and resource utilization subsystem. The CO sensing and safety control subsystem is used to monitor CO concentration and is connected to the biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit.

[0010] This invention combines solar thermal heating, biomass gasification heating, gasification waste heat recovery, and the systematic resource utilization of wood ash, wood vinegar, and tar. It also integrates multi-point CO sensing and interlocking safety control, making it particularly suitable for distributed heating scenarios such as rural residences, greenhouses, and small public buildings.

[0011] A second aspect of the present invention provides a method for operating the above-mentioned system of solar thermal-biomass gasification combined heating and multi-product soil conditioner and tree protection material, characterized in that it includes: 1) Monitor indoor temperature, solar collector temperature and hot water storage tank temperature to determine whether heating is provided solely by the solar hot water storage tank or simultaneously by starting the biomass fixed-bed gasifier; 2) When solar energy is insufficient, start the gasifier to gasify biomass in the fixed-bed gasifier to generate high-temperature syngas and wood ash char. 3) The high-temperature syngas is passed through a syngas cooler to exchange heat with the heating return water. After recovering the sensible heat of the syngas, it is sent to a spray cooling tower and condenser to generate condensate containing tar and wood vinegar. The syngas is then purified by gas-solid separation. 4) Use an oil-water separator to separate the condensate into an organic phase of tar and an aqueous phase of wood vinegar, which are then sent to tar storage tanks and wood vinegar storage tanks, respectively. 5) The purified syngas is sent to the gas boiler for combustion, and the generated hot water or steam is supplied to the building heating circuit through the heat exchanger. At the same time, the waste heat of the furnace water jacket and boiler flue gas is recovered and incorporated into the heating system. 6) The cooled wood ash charcoal is crushed and sieved to make wood ash charcoal soil conditioner and applied to the soil. Wood vinegar is settled, filtered and diluted and used for soil improvement and plant growth conditioning. Tar is used for tree insect prevention, anti-corrosion and wound sealing. 7) Continuously monitor the CO concentration in the equipment room and / or living space throughout the entire operation. When the CO concentration exceeds the preset threshold, perform protective operations such as ventilation, furnace shutdown and cutting off the syngas supply.

[0012] Beneficial effects of the present invention (1) Complementary heat sources improve heating reliability and renewable energy utilization. This invention organically couples solar thermal energy with biomass fixed-bed gasification, utilizing solar energy to achieve low-carbon heating and using gasified gas to drive a gas boiler to provide a stable heat source when solar energy is insufficient, thus solving the problem of unstable heating from a single solar energy source.

[0013] (2) Multi-stage waste heat recovery improves the overall energy efficiency of the system. This invention utilizes multi-stage waste heat recovery through a syngas cooler, a gasifier water jacket, and a gas boiler flue gas heat exchanger to fully utilize the sensible heat from the gasification and combustion processes for heating, significantly improving the overall system efficiency and reducing biomass consumption.

[0014] (3) Achieve multi-generational benefits including heating, soil improvement, and plant protection. This invention utilizes wood ash as a soil conditioner, wood vinegar as a soil and plant conditioner, and wood tar as a pest and rot prevention material for trees, to achieve an organic integration of heating systems with agricultural production and landscaping, thereby increasing the added value of agricultural and forestry waste.

[0015] (4) Comprehensive CO monitoring and interlocking control significantly reduce the risk of poisoning. The interlocking mechanism between the multi-point CO sensor and the fan, solenoid valve, and combustion control system of this invention can provide ventilation warnings in the early stages of CO concentration increase and automatically shut down the furnace and cut off gas supply when the dangerous threshold is reached, effectively preventing CO poisoning accidents. It is suitable for safe application in environments such as rural residences, greenhouses, and small computer rooms.

[0016] (5) The system structure is relatively simple, which facilitates engineering implementation and promotion. This invention uses conventional solar collectors, fixed-bed gasifiers, gas boilers and other mature equipment, and integrates them through reasonable heat exchange and control strategies. The system has a clear structure, is easy to maintain, and is suitable for promotion and application in small and medium-sized heating projects. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. Exemplary embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 : Schematic diagram of the overall structure of the system of this invention; Figure 2 Schematic diagram of biomass fixed-bed gasifier and wood ash collection device; Figure 3 Schematic diagram of the synthesis gas cooling, purification and gas boiler heating unit; Figure 4 Schematic diagram of the separation, storage, and utilization of wood vinegar and tar; Figure 5 Schematic diagram of CO sensor and safety interlock control logic; Figure 6 : Schematic diagram of system operation mode switching process (solar priority, combined heating, gasification main heating). Detailed Implementation

[0019] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art. The reagents and raw materials used in this invention are readily available through conventional means, and unless otherwise specified, they are used in accordance with conventional methods in the art or product instructions. Similarly, unless otherwise specified, the test methods of this invention are performed in accordance with conventional methods in the art or industry-standard methods or practices. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to the methods of this invention. The preferred embodiments and materials described herein are for illustrative purposes only.

[0021] As described in the background section, current single solar thermal heating is greatly limited by climate conditions and lacks heating stability; in biomass gasification heating systems, gasification gas is not fully utilized efficiently, and waste heat is wasted during the gasification process; byproducts such as wood ash, wood charcoal, wood vinegar, and tar are not utilized systematically and with high added value; small-scale biomass gasification heating systems lack comprehensive carbon monoxide monitoring and interlocking control, posing a risk of CO poisoning; and there is a lack of small-scale, relatively simple, and scalable integrated solar thermal-biomass fixed-bed gasification combined heating and multi-generation technology solutions suitable for rural energy systems.

[0022] Therefore, the present invention provides a system for combined solar thermal and biomass gasification heating and multi-product soil conditioner and tree protection material, comprising: a solar thermal subsystem, a biomass gasification and heating subsystem, a syngas cooling, purification and gas boiler heating unit, a building heating circuit and waste heat recovery unit, a by-product collection and resource utilization subsystem, and a CO sensing and safety control subsystem. The solar thermal subsystem, biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit are respectively connected to the building heating circuit and waste heat recovery unit. The condensate outlet of the syngas cooling, purification and gas boiler heating unit is also connected to the by-product collection and resource utilization subsystem. The CO sensing and safety control subsystem is used to monitor CO concentration and is connected to the biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit.

[0023] Preferably, the solar thermal subsystem includes: a solar collector array, a solar circulation loop, a hot water storage tank, and a solar-gasification coupling heat exchanger; a solar circulation loop is provided between the solar collector array and the hot water storage tank, and the solar circulation loop is also connected to the solar-gasification coupling heat exchanger. The solar-gasification coupling heat exchanger is used to transfer heat from the solar hot water storage tank to the primary air of the gasifier, the fuel pre-drying device, and / or the building heating circuit; Preferably, the biomass gasification and heating subsystem includes: a biomass gasifier; the biomass gasifier is connected to a primary air supply system and a secondary air supply system respectively; a water jacket cooling structure is provided on the outside of the biomass gasifier; and the feed inlet of the biomass gasifier is connected to a hopper / feeding device.

[0024] Preferably, the syngas cooling, purification, and gas-fired boiler heating unit includes: a syngas cooler, a spray cooling tower, a condenser, a condensate collection and oil-water separator, a gas-solid separation unit, and a gas-fired boiler; the inlet of the syngas cooler is connected to the syngas outlet of the gasifier, the outlet of the syngas cooler is connected to the spray cooling tower / condenser, the outlet of the spray cooling tower / condenser is connected to the condensate collection and oil-water separator, and the outlet of the spray cooling tower / condenser is sequentially connected to the gas-solid separation unit and the gas-fired boiler. The syngas cooler is used to recover the sensible heat of the high-temperature syngas for heating by exchanging heat with the heating circuit water or intermediate working fluid; Preferably, the building heating circuit and waste heat recovery unit includes: multiple heating heat exchangers, which are respectively connected to the outlet of the hot water storage tank, the outlet or steam outlet of the gas boiler, and the outlet of the boiler body water jacket cooling structure. The gas boiler uses cooled and purified syngas as fuel to provide hot water or steam to the building heating circuit; Preferably, the by-product collection and resource utilization subsystem includes: a wood ash collection and cooling device, a wood ash conditioning device, a wood vinegar storage and blending device, and a tar storage and application device; the wood ash collection and cooling device includes: an ash collection chamber / slag area, a spiral ash discharge mechanism, and a sealed ash barrel; the wood vinegar storage and blending device includes a wood vinegar storage tank and a wood vinegar blending device; the tar storage and application device includes: a tar storage tank and a tar application device; the outlet of the biomass gasifier is sequentially connected to the ash collection chamber / slag area, the spiral ash discharge mechanism, and the sealed ash barrel, and the sealed ash barrel is equipped with an air-cooled or water-cooled device; the condensate collection and oil-water separation tank is connected to the wood vinegar storage tank and the tar storage tank respectively. The condensate collection and oil-water separation tank is used to separate the condensate into an organic phase mainly composed of tar and an aqueous phase mainly composed of wood vinegar, which are used for tree protection and soil improvement, respectively; the wood ash collection and cooling device is used to cool and seal the wood ash produced during the gasification process for the preparation of soil conditioner. Preferably, the CO sensing and safety control subsystem includes: at least one CO sensor and a controller connected thereto, wherein the controller is electrically connected to an exhaust fan, a fresh air valve, and an audible and visual alarm; the controller performs protective operations such as ventilation, furnace shutdown, and cutting off the syngas supply based on the CO concentration signal detected by the CO sensor.

[0025] The controller is also connected to the biomass gasification furnace control system and the gas boiler control system, respectively.

[0026] Preferably, the biomass gasifier is a fixed-bed biomass gasifier, which adopts an upward or downward suction fixed-bed structure, including a furnace shell, refractory lining, hopper, feeding mechanism, fixed grate and ash collection chamber; the gasification equivalence ratio and furnace temperature are controlled by adjusting the primary air and secondary air volume and distribution ratio, so that some biomass is kept in a carbonized state and the yield of charcoal is improved.

[0027] Preferably, the solar-gasification coupled heat exchanger is installed in the gasification primary air duct and / or fuel pre-drying chamber; it is used to transfer heat from the solar hot water tank to the primary air and / or biomass fuel, thereby reducing the fuel moisture content and improving gasification stability.

[0028] Preferably, the syngas cooler is a water-gas heat exchanger, with its water side connected to the return water of the building's heating circuit; the recovered sensible heat of the syngas is used to increase the return water temperature, thereby reducing the load on the gas-fired boiler.

[0029] Preferably, a condensate collection and oil-water separation tank is provided after the spray cooling tower and condenser. The upper part of the oil-water separation tank is the organic phase outlet of tar, and the lower part is the aqueous phase outlet of wood vinegar, which are respectively connected to the tar storage tank and the wood vinegar storage tank.

[0030] Preferably, the plant ash collection and cooling device includes a spiral ash discharge mechanism and a sealed ash barrel. The spiral ash discharge mechanism transports the high-temperature plant ash from the ash collection chamber to the sealed ash barrel. The sealed ash barrel is equipped with a natural air cooling or forced air cooling structure to cool the plant ash to no higher than 60°C.

[0031] Preferably, the plant ash charcoal conditioning device includes a crusher and a screening device; used to crush and screen the cooled plant ash charcoal to a predetermined particle size range, remove impurities such as metal and stones, and form a plant ash charcoal soil conditioner.

[0032] Preferably, the wood vinegar preparation device includes a sedimentation tank and a filtration device; after sedimentation and filtration, the wood vinegar is diluted according to a set ratio and mixed with irrigation water or foliar spray solution for use as a soil conditioner and plant growth regulator.

[0033] Preferably, the tar application device includes a heating / dilution unit; after the tar is heated and softened or diluted, it is applied to the surface of the tree trunk or tree wounds by brushing or spraying, and used as a tree insect-proofing, anti-corrosion and wound sealing material.

[0034] Preferably, the CO sensor includes a first CO sensor installed in the equipment room and a second CO sensor installed in the living space. The controller sets a low threshold and a high threshold according to the CO concentration. When the detection value of either CO sensor exceeds the low threshold, the exhaust fan is started and an audible and visual alarm is issued. When the detection value of either CO sensor exceeds the high threshold, the syngas supply is cut off, the gasifier and the gas boiler are stopped, and the exhaust is maintained until the CO concentration returns to below a safe value. The controller is also connected to an indoor temperature sensor, a solar collector temperature sensor, and a hot water storage tank temperature sensor. It is used to automatically select at least one operating mode from the following: solar-priority heating mode, solar-gasification combined heating mode, and gasification main heating mode, based on indoor temperature requirements and solar radiation conditions.

[0035] More specifically, 1. System Overall Structure A system for combined solar thermal and biomass gasification heating and multi-product soil conditioner and tree protection materials includes: Solar thermal subsystem Solar collector arrays: These can be evacuated tube collectors, flat plate collectors, or trough collectors, used to collect solar radiation; Solar circulation loop: including circulation pump, pipeline, valve and temperature sensor, used to transport heat transfer medium; Solar-powered hot water storage tank: used to store solar energy; Solar-gasification coupled heat exchanger: used to transfer solar heat to the primary air of the gasifier, fuel pre-drying unit and / or building heating circuit.

[0036] The biomass gasification and heating subsystem includes: (1) Biomass gasifier: The gasifier can be an up-suction fixed bed gasifier, a composite gas-suction fixed bed gasifier, or a fluidized bed gasifier.

[0037] When using an upward-suction fixed-bed gasifier, biomass is added from the top, and the gas flow is from bottom to top. The furnace body includes a furnace shell, refractory lining, hopper, feeding mechanism, fixed grate, ash and coal collection chamber, and ash discharge mechanism. The gasification equivalence ratio and furnace temperature are controlled by adjusting the primary air and secondary air volume and distribution ratio.

[0038] When a composite suction fixed-bed gasifier is used, a flow guiding structure is set inside the furnace so that part of the airflow is from bottom to top and part of the airflow is from top to bottom. This combines the advantages of lower tar content of the upward suction type and stable ignition of the downward suction type, thereby improving gasification stability while reducing tar content.

[0039] When a fluidized bed gasifier is used, biomass fuel, bed material, and catalyst particles are fluidized together in the fluidized bed. A bubbling fluidized bed or a bubbling-circulating composite fluidized bed structure is preferred. A catalyst with tar cracking and reforming effects is added to the bed, and the bed temperature is maintained within a predetermined range (e.g., 700–900°C) by measuring the bed temperature and adjusting the airflow to reduce the tar content in the syngas.

[0040] (2) Primary and secondary air supply systems, equipped with fans and regulating valves, are used to supply the oxidant required for gasification to fixed bed or fluidized bed gasifiers, and to control the gasification equivalence ratio and furnace temperature by adjusting the air volume and distribution ratio.

[0041] (3) A water jacket or jacketed cooling structure for the furnace body, used to form a cooling circuit for the furnace body, and to recover the heat dissipation of the furnace body to the heating system or hot water storage tank. Syngas outlet and syngas cooling and purification unit.

[0042] Syngas cooling, purification and gas boiler heating unit Syngas cooler: It cools high-temperature syngas by heat exchange. The high-temperature side is gasified gas, and the low-temperature side is heating return water or intermediate heat exchange medium, so as to realize the recovery of sensible heat of gasified gas and its integration into the heating system. Spray cooling tower and condenser: further cool the syngas to produce condensate containing tar and wood vinegar; Condensate collection and oil-water separation tank: Separates the condensate into an organic phase mainly composed of tar and an aqueous phase mainly composed of wood vinegar; Gas-solid separation unit: including cyclone separator and / or filter element, used to remove dust and fine carbon particles; Gas-fired boilers: connected to purified syngas, which is burned as fuel to produce hot water or steam, which is then supplied to the building's heating circuit via a heat exchanger.

[0043] Building heating circuits and waste heat recovery units Building heating circuits include circulating pumps, radiators or floor radiant coils, expansion tanks, etc., which are connected to solar water storage tanks and heat exchangers of gas boilers. Waste heat recovery from the boiler water jacket: Hot water in the boiler water jacket is pumped into a hot water storage tank or exchanged with the heating circuit via a circulating pump, and the heat dissipated from the boiler is recovered for heating. Waste heat recovery unit for gas-fired boiler flue gas: Installed on the boiler flue, it recovers part of the sensible heat of the flue gas through a flue gas-water heat exchanger and integrates it into the heating system.

[0044] By-product collection and resource utilization subsystem Plant ash collection and cooling device: installed at the bottom or side of the gasifier, including a spiral ash discharge mechanism, a sealed ash bucket and a cooling structure, used to cool the high temperature plant ash to a safe temperature and collect it in a sealed manner; Wood ash charcoal conditioning device: including a crusher and a screening device, used to shape wood ash charcoal into suitable particle size and remove impurities such as metal and stones; Wood vinegar storage and preparation device: used to store the aqueous phase (wood vinegar) obtained after oil-water separation, and to perform sedimentation, filtration and dilution preparation for use as a soil conditioner and plant growth regulator; Tar storage and application equipment: used to store organic phase tar and adjust its viscosity by heating or dilution when in use, for use as a material for insect prevention, anti-corrosion and wound sealing of trees.

[0045] CO Sensing and Safety Control Subsystem CO sensors: including at least a first CO sensor arranged in the gasification equipment room, and a second CO sensor arranged in a representative living space or work area; online CO sensors may also be arranged in the flue gas duct if necessary. Controller: PLC or embedded industrial controller can be used, which is electrically connected to CO sensor, temperature sensor, fan, solenoid valve, burner, exhaust fan and audible and visual alarm; Interlocking control logic: Based on the CO concentration, multiple threshold levels are set. When the CO concentration reaches the low threshold, the exhaust fan is automatically started and an audible and visual alarm is triggered. When the CO concentration reaches the high threshold or the danger threshold, the syngas supply is automatically cut off, the gasifier primary air fan and the gas boiler are stopped, and exhaust and ventilation are maintained until the CO concentration drops below the safe value. The alarm event is recorded and the system is locked. It can only be reset after manual inspection and confirmation.

[0046] System operation control strategy The controller integrates indoor temperature, solar collector temperature, hot water storage tank temperature, supply and return water temperatures, and gasifier operating status to automatically switch or combine the following operating modes: Solar priority heating mode: When solar energy resources are sufficient, the solar hot water storage tank is used to supply heat to the building heating circuit, and the gasifier is shut down or on low load standby. Solar-Gasification Combined Heating Mode: Solar energy provides partial heating, and the biomass gasification system provides supplementary heat source. Solar heat is used to preheat primary air, dry fuel, and / or provide partial heating. Gasification as the main heating mode: At night or during continuous cloudy and rainy weather, the gasifier and gas boiler serve as the main heat source, and if there is solar energy output, it is given priority for fuel pre-drying or supplementing heat storage.

[0047] 2. Methods for comprehensive utilization of by-products Based on the above system, the present invention also proposes the following method for comprehensive utilization of by-products: Wood ash charcoal utilization The mixture of wood ash and wood charcoal produced by the gasifier is fed into a sealed ash and charcoal bucket through a spiral ash discharge mechanism, and cooled to no higher than 60°C under natural or forced air cooling conditions. After cooling, the wood ash is crushed and sieved to control the particle size within a certain range (e.g., 1-10 mm) and non-combustible impurities are removed. The charcoal portion, as a porous carbon material, increases the soil's organic carbon content and water and fertilizer retention capacity; the wood ash portion provides alkaline nutrients such as potassium and calcium, and also has a pH-regulating effect. Mix wood ash and wood charcoal in a set ratio to make wood ash charcoal soil conditioner, which can be used for soil improvement in farmland, gardens or nurseries.

[0048] Wood vinegar utilization The condensate is separated into an aqueous phase, namely wood vinegar, after oil-water separation. After sedimentation and filtration to remove suspended particles, wood vinegar can be diluted in a certain proportion and applied to the soil or used as a foliar spray for crops. As a soil amendment aid, it improves the soil microbial environment; As a plant growth regulator, it promotes root growth and has a certain inhibitory effect on some diseases and pests.

[0049] Tar utilization Organic phase tar is stored in tar storage tanks and softened by heating or appropriately diluted before application; Tar is applied to the surface of tree trunks, pruning wounds, grafting sites, etc., to form a protective layer. It is used to prevent insects, rot, and pathogen invasion, and to reduce water loss from wounds. It is suitable for plant protection scenarios such as fruit trees and landscaping trees.

[0050] 3. CO safety protection features This invention achieves CO safety protection in the following ways: Multiple CO sensors are deployed to monitor CO concentrations in equipment rooms, living spaces, and, when necessary, smoke exhaust ducts; Set multi-level CO concentration thresholds to achieve a graded response from early warning and enhanced ventilation to emergency shutdown; When CO exceeds the standard, the controller automatically cuts off the primary air fan of the gasifier, the solenoid valve of the syngas pipeline and the gas supply of the gas boiler through hardware interlocking to prevent further CO leakage. The system records and locks out events with severe CO exceedances, requiring manual inspection and reset before it can be restarted, thus enhancing the inherent safety level of the system.

[0051] The present invention also provides a method for operating the above-mentioned solar thermal-biomass gasification combined heating and multi-product soil conditioner and tree protection material system, comprising: 1) Monitor indoor temperature, solar collector temperature and hot water storage tank temperature to determine whether heating is provided solely by the solar hot water storage tank or simultaneously by starting the biomass fixed-bed gasifier; 2) When solar energy is insufficient, start the gasifier to gasify biomass in the fixed-bed gasifier to generate high-temperature syngas and wood ash char. 3) The high-temperature syngas is passed through a syngas cooler to exchange heat with the heating return water. After recovering the sensible heat of the syngas, it is sent to a spray cooling tower and condenser to generate condensate containing tar and wood vinegar. The syngas is then purified by gas-solid separation. 4) Use an oil-water separator to separate the condensate into an organic phase of tar and an aqueous phase of wood vinegar, which are then sent to tar storage tanks and wood vinegar storage tanks, respectively. 5) The purified syngas is sent to the gas boiler for combustion, and the generated hot water or steam is supplied to the building heating circuit through the heat exchanger. At the same time, the waste heat of the furnace water jacket and boiler flue gas is recovered and incorporated into the heating system. 6) The cooled wood ash charcoal is crushed and sieved to make wood ash charcoal soil conditioner and applied to the soil. Wood vinegar is settled, filtered and diluted and used for soil improvement and plant growth conditioning. Tar is used for tree insect prevention, anti-corrosion and wound sealing. 7) Continuously monitor the CO concentration in the equipment room and / or living space throughout the entire operation. When the CO concentration exceeds the preset threshold, perform protective operations such as ventilation, furnace shutdown and cutting off the syngas supply.

[0052] Preferably, the biomass gasifier is one of an updraft fixed-bed gasifier, a composite updraft fixed-bed gasifier, or a fluidized-bed gasifier; wherein, when a fluidized-bed gasifier is used, bed material and catalyst particles are set in the bed, and the bed temperature is maintained within a predetermined range by measuring the bed temperature and adjusting the air volume, so as to reduce the tar content in the syngas. Preferably, the catalyst particles are one or more of oxide, carbonate, or natural mineral catalysts with tar cracking and reforming functions, and the fluidized bed gasifier is a bubbling fluidized bed or a bubbling-circulating composite fluidized bed structure.

[0053] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0054] Example 1: Application of Combined Heating and Soil Improvement in Rural Independent Houses System Configuration The solar collector has an area of ​​approximately 30 m² and uses a vacuum tube collector. The hot water storage tank has a volume of approximately 1.5 m³ and contains internal heat exchange coils for heat exchange with the building's heating circuit. The biomass fixed-bed gasifier has a rated thermal power of approximately 40 kW, and the fuel is straw briquettes and wood chips; The syngas is cooled, dusted, and purified before entering a 40 kW gas-fired hot water boiler; The building heating system is floor radiant heating, with a supply water temperature of about 45℃ and a return water temperature of about 35℃. The gasifier is equipped with an external water jacket, which, together with the hot water storage tank, forms a cooling circuit for the gasifier body. The syngas cooler uses a shell-and-tube heat exchanger to exchange heat between the high-temperature syngas and the heating return water. A wood vinegar storage tank and a tar storage tank are installed after the condensate oil-water separator; The plant ash and charcoal collection device adopts a spiral ash discharge mechanism and a sealed double-layer ash and charcoal barrel; One CO sensor is placed in the equipment room and one in the living room of the residence.

[0055] Running process (1) On a sunny day with plenty of sunshine: The solar collectors supply heat to the hot water storage tank, which then supplies heat to the floor heating circuit through coils. Once the indoor temperature reaches the set value (e.g., 20℃), the controller adjusts the water pump flow rate to maintain the room temperature. The gasifier is in a shutdown or low-load heat preservation state, maintaining only fuel standby.

[0056] (2) In the evening or on cloudy days when solar energy is insufficient: When the controller detects that the temperature of the hot water storage tank is insufficient to meet the heating demand, it starts the gasifier ignition program. Biomass enters the fixed bed through the hopper, ignites under the action of primary air, and enters the stable gasification stage; The high-temperature syngas first exchanges heat with the heating return water in the syngas cooler to recover sensible heat; It then enters the spray cooling tower and condenser, generating condensate containing tar and wood vinegar, which further reduces the gas temperature; After gas-solid separation and safety testing, the purified syngas is sent to the gas boiler for combustion, and the hot water produced by the boiler is sent to the heating circuit through a heat exchanger. The hot water in the boiler's water jacket continuously carries away heat from the boiler and returns to the hot water storage tank or heating system.

[0057] (3) During nighttime or continuous rainy weather, the gasification main heating mode will be used: The gasifier operates continuously as the main heat source; If solar energy still has a small output, it should be used first to preheat the primary air of the gasification process or to dry the biomass fuel in the storage silo.

[0058] By-product utilization and safety control The wood ash produced during the gasification process falls into the ash collection chamber, is then transported to a sealed ash bucket by a screw conveyor, and is removed after natural cooling or assisted forced air cooling. After cooling, the wood ash is crushed and sieved, and then used as a soil conditioner for farmland. It is mixed with topsoil or organic fertilizer at a mass fraction of 5% to 10% and then turned into the tillage layer. After the condensate is separated from the oil and water, the wood vinegar is stored in a wood vinegar storage tank. When used, it is mixed with irrigation water or spray solution in a certain proportion to improve the soil and regulate plant growth. The tar is stored in tar tanks. When pruning fruit trees in winter or controlling pests and diseases, it is heated and softened, then applied to the wounds on the branches and trunks of the fruit trees as a material for preventing insects, decay, and cracking.

[0059] CO safety control aspects: When any CO sensor detects a value that reaches the low alarm threshold (e.g., 30 ppm), the controller automatically starts the exhaust fan in the equipment room, opens the fresh air vent, and issues an audible and visual alarm to remind the user to pay attention to ventilation. When the CO concentration rises further to the high alarm threshold (e.g., 60 ppm), the controller immediately executes the emergency shutdown procedure: Cut off the synthesis gas supply solenoid valve; Stop operating the primary air fan of the gasifier and the gas-fired boiler; Keep the exhaust fan running until the CO concentration drops below a safe level; Record alarm events and lock the system status; it can only be reset after manual inspection confirms that the cause has been eliminated.

[0060] Through the above embodiments, the present invention realizes complementary heating of solar energy and biomass heat sources in rural residences, makes full use of waste heat from the gasification process, and fully utilizes the resources of wood ash, wood vinegar and tar, while significantly improving the CO safety protection level of the system.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material, characterized in that, include: Solar thermal subsystem, biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit, building heating circuit and waste heat recovery unit, by-product collection and resource utilization subsystem, CO sensing and safety control subsystem; The solar thermal subsystem, biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit are respectively connected to the building heating circuit and waste heat recovery unit. The condensate outlet of the syngas cooling, purification and gas boiler heating unit is also connected to the by-product collection and resource utilization subsystem. The CO sensing and safety control subsystem is used to monitor CO concentration and is connected to the biomass gasification and heating subsystem, syngas cooling, purification and gas boiler heating unit.

2. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The solar thermal subsystem includes: a solar collector array, a solar circulation loop, a hot water storage tank, and a solar-gasification coupling heat exchanger; a solar circulation loop is provided between the solar collector array and the hot water storage tank, and the solar circulation loop is also connected to the solar-gasification coupling heat exchanger.

3. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The biomass gasification and heating subsystem includes: a biomass gasifier; the biomass gasifier is connected to a primary air supply system and a secondary air supply system respectively; a water jacket cooling structure is provided on the outside of the biomass gasifier; and the feed inlet of the biomass gasifier is connected to a hopper / feeding device.

4. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The syngas cooling, purification, and gas-fired boiler heating unit includes: a syngas cooler, a spray cooling tower, a condenser, a condensate collection and oil-water separator, a gas-solid separation unit, and a gas-fired boiler; the inlet of the syngas cooler is connected to the syngas outlet of the gasifier, the outlet of the syngas cooler is connected to the spray cooling tower / condenser, the outlet of the spray cooling tower / condenser is connected to the condensate collection and oil-water separator, and the outlet of the spray cooling tower / condenser is sequentially connected to the gas-solid separation unit and the gas-fired boiler.

5. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The building heating circuit and waste heat recovery unit includes: multiple heating heat exchangers, which are respectively connected to the outlet of the hot water storage tank, the outlet or steam outlet of the gas boiler, and the outlet of the boiler body water jacket cooling structure.

6. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The by-product collection and resource utilization subsystem includes: a wood ash collection and cooling device, a wood ash conditioning device, a wood vinegar storage and blending device, and a tar storage and application device; the wood ash collection and cooling device includes: an ash collection chamber / slag area, a spiral ash discharge mechanism, and a sealed ash barrel; the wood vinegar storage and blending device includes a wood vinegar storage tank and a wood vinegar blending device; the tar storage and application device includes: a tar storage tank and a tar application device; the outlet of the biomass gasifier is sequentially connected to the ash collection chamber / slag area, the spiral ash discharge mechanism, and the sealed ash barrel, and the sealed ash barrel is equipped with an air-cooled or water-cooled device; the condensate collection and oil-water separation tank is connected to the wood vinegar storage tank and the tar storage tank respectively.

7. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The CO sensing and safety control subsystem includes: at least one CO sensor and a controller connected thereto, wherein the controller is electrically connected to an exhaust fan, a fresh air valve, and an audible and visual alarm. The controller is also connected to the biomass gasification furnace control system and the gas boiler control system, respectively.

8. The system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 1, characterized in that, The biomass gasifier is a fixed-bed biomass gasifier, which adopts an upward or downward suction fixed-bed structure, including a furnace shell, refractory lining, hopper, feeding mechanism, fixed grate and ash collection chamber. Alternatively, the solar-gasification coupled heat exchanger may be installed in the gasification primary air duct and / or fuel pre-drying chamber; Alternatively, the syngas cooler is a water-gas heat exchanger, with its water side connected to the return water of the building's heating circuit. Alternatively, the plant ash charcoal conditioning device may include a crusher and a sieving device; Alternatively, the wood vinegar preparation device may include a settling tank and a filtration device; Alternatively, the tar application device may include a heating / dilution unit; Alternatively, the CO sensor includes: a first CO sensor installed in the equipment room and a second CO sensor installed in the living space. The controller sets a low threshold and a high threshold according to the CO concentration. When the detection value of either CO sensor exceeds the low threshold, the exhaust fan is started and an audible and visual alarm is issued. When the detection value of either CO sensor exceeds the high threshold, the syngas supply is cut off, the gasifier and gas boiler are stopped, and the exhaust is maintained until the CO concentration returns to below a safe value. The controller is also connected to an indoor temperature sensor, a solar collector temperature sensor, and a hot water storage tank temperature sensor.

9. A method for operating a system of solar thermal-biomass gasification combined heating and multi-product soil conditioner and tree protection material as described in any one of claims 1-8, characterized in that, include: 1) Monitor indoor temperature, solar collector temperature and hot water storage tank temperature to determine whether heating is provided solely by the solar hot water storage tank or simultaneously by starting the biomass fixed-bed gasifier; 2) When solar energy is insufficient, start the gasifier to gasify biomass in the fixed-bed gasifier to generate high-temperature syngas and wood ash char. 3) The high-temperature syngas is passed through a syngas cooler to exchange heat with the heating return water. After recovering the sensible heat of the syngas, it is sent to a spray cooling tower and condenser to generate condensate containing tar and wood vinegar. The syngas is then purified by gas-solid separation. 4) Use an oil-water separator to separate the condensate into an organic phase of tar and an aqueous phase of wood vinegar, which are then sent to tar storage tanks and wood vinegar storage tanks, respectively. 5) The purified syngas is sent to the gas boiler for combustion, and the generated hot water or steam is supplied to the building heating circuit through the heat exchanger. At the same time, the waste heat of the furnace water jacket and boiler flue gas is recovered and incorporated into the heating system. 6) The cooled wood ash charcoal is crushed and sieved to make wood ash charcoal soil conditioner and applied to the soil. Wood vinegar is settled, filtered and diluted and used for soil improvement and plant growth conditioning. Tar is used for tree insect prevention, anti-corrosion and wound sealing. 7) Continuously monitor the CO concentration in the equipment room and / or living space throughout the entire operation. When the CO concentration exceeds the preset threshold, perform protective operations such as ventilation, furnace shutdown and cutting off the syngas supply.

10. The operating method of the system for combined solar thermal-biomass gasification heating and multi-product soil conditioner and tree protection material as described in claim 9, characterized in that, The biomass gasifier is one of an updraft fixed-bed gasifier, a composite updraft fixed-bed gasifier, or a fluidized-bed gasifier; wherein, when a fluidized-bed gasifier is used, bed material and catalyst particles are set in the bed, and the bed temperature is maintained within a predetermined range by measuring the bed temperature and adjusting the air volume, so as to reduce the tar content in the syngas. Alternatively, the catalyst particles may be one or more of oxide, carbonate, or natural mineral catalysts with tar cracking and reforming functions, and the fluidized bed gasifier may be a bubbling fluidized bed or a bubbling-circulating composite fluidized bed structure.

Images