Rural multi-source solid waste energy and resource utilization system

Abstract

The invention discloses a rural multi-source solid waste energy regeneration and resource utilization system. The system comprises a dry solid waste incineration power generation system, a high-water-content solid waste supercritical gasification system, an ecological agriculture integration system and a hydrogen-carbon-methanol storage and transportation system. According to the method, agricultural wastes such as straws and livestock manure are integrated and are converted into organic fertilizers to be returned to the field after being treated, so that the soil fertility is improved, the yield increase of the planting industry is promoted, stable supply of rural energy is guaranteed, the energy utilization efficiency is improved, economic benefits can be created by selling methanol, the development of the planting industry and the breeding industry is promoted, and energy and resource utilization of solid wastes is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of resource utilization, and more specifically, to a system for the energy conversion and resource utilization of multiple sources of solid waste in rural areas. Background Art

[0002] With the development of the rural economy and the transformation of the lifestyle, the generation of solid waste in rural areas is increasing day by day. According to statistics, the annual generation of rural domestic waste in China exceeds 200 million tons and continues to rise. Approximately 50% of rural areas lack a complete waste collection system, and a large amount of waste is discarded randomly, polluting the environment. The annual generation of livestock and poultry manure is about 3.8 billion tons, and the comprehensive utilization rate is only about 75%. The annual output of straw exceeds 700 million tons, and the comprehensive utilization rate is about 86%. Some are burned or discarded, causing waste of resources and environmental pollution. In addition, the traditional and single rural energy utilization method has a low proportion of clean energy utilization. The stability of rural power supply is poor, and remote areas often face power shortages. Moreover, there is a lack of energy storage and conversion facilities, resulting in serious energy waste.

[0003] As an emerging treatment technology, the supercritical H2 production technology shows unique advantages in the field of solid waste treatment and can convert perishable kitchen waste, rural toilet feces, livestock and poultry manure, etc. into H2. This technology can not only achieve the reduction and harmless treatment of solid waste but also efficiently recover energy. Compared with traditional treatment methods, its energy recovery rate is higher, the products are clean and easy to separate, providing a new way for the energy conversion and resource utilization of high-water-content solid waste.

[0004] Therefore, how to use the supercritical H2 production technology to treat multiple sources of solid waste in rural areas is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a system for the energy conversion and resource utilization of multiple sources of solid waste in rural areas to solve the deficiencies in the prior art.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A system for the energy conversion and resource utilization of multiple sources of solid waste in rural areas includes a dry solid waste incineration power generation system, a supercritical gasification system for high-water-content solid waste, an ecological agriculture integration system, and a hydrogen-carbon methanol storage and transportation system.

[0008] Further, the above-mentioned dry solid waste incineration power generation system includes a domestic waste classification device, a solid waste incineration waste heat boiler, a power generation device, and a CO2 capture device.

[0009] The further beneficial effects of the above are as follows. The dry solid waste incineration power generation system is used to classify and incinerate domestic dry garbage and off-field straw for power generation, and capture the CO2 generated by combustion. The electricity generated is preferentially supplied to the supercritical gasification system for high-moisture solid waste, and the remaining electricity is used for villagers' production and living electricity. Among them, the domestic waste classification device is used to classify domestic waste into dry garbage and kitchen waste; the waste incineration waste heat boiler is used to incinerate dry solid waste to generate high-temperature flue gas, and use the heat of the high-temperature flue gas to generate steam to drive the power generation device to generate electricity; the CO2 capture device uses the MEA (monoethanolamine) chemical absorption method to capture CO2 in the flue gas.

[0010] Furthermore, the above domestic waste classification device includes a garbage input port, an automatic sorting machine, a classified storage bin, and a garbage conveying system.

[0011] The further beneficial effects of the above are as follows. The domestic waste classification device is used to classify domestic waste into dry garbage and kitchen waste by mechanical screening, optical recognition, and weight sensing technologies, and convey them to the dry solid waste incineration power generation system and the supercritical gasification system for high-moisture solid waste respectively.

[0012] Furthermore, the CO2 captured by the above CO2 capture device is compressed and stored, and then transported through pipelines to the microalgae cultivation module of the ecological agriculture integration system.

[0013] Further, the above supercritical gasification system for high-moisture solid waste includes a supercritical gasification reactor and a gas separation and purification device.

[0014] The further beneficial effects of the above are as follows. The H2 generated by the supercritical gasification system for high-moisture solid waste is used for local villagers' vehicles and mechanical equipment, and the surplus H2 reacts with the CO2 captured by the dry solid waste incineration power generation to generate methanol, which is stored or transported out.

[0015] Furthermore, the H2-containing mixed gas generated by the above supercritical gasification reactor is purified by the gas separation and purification device and then transported through pipelines to the hydrogen-carbon methanol storage and transportation system, and the surplus H2 is supplied for villagers' vehicles and mechanical equipment to use.

[0016] The further beneficial effects of the above are as follows. The supercritical gasification reactor converts organic waste such as kitchen waste, rural toilet feces, and surplus livestock and poultry manure and microalgae remaining after returning to the field transported by the domestic waste classification device into an H2-containing mixed gas; the gas separation and purification device uses pressure swing adsorption and membrane separation technologies to purify H2.

[0017] Further, the above ecological agriculture integration system includes a microalgae cultivation and utilization module, a grain planting module, and a livestock and poultry breeding module.

[0018] The further beneficial effects of the above are as follows: The microalgae cultivation and utilization module captures CO2 to cultivate microalgae, produces organic feed, and the surplus microalgae are used for fuel utilization; the grain planting module uses straw retting and anaerobic fermentation technology of livestock and poultry manure to produce organic fertilizers and improve soil fertility; the livestock and poultry breeding module receives organic feed and transports part of the manure to the supercritical gasification system for high-moisture solid waste.

[0019] Furthermore, the above microalgae cultivation and utilization module includes a photobioreactor, an aeration device, and a nutrient supply device. The surplus microalgae are dried and then enter the supercritical gasification system for high-moisture solid waste to produce H2 by gasification.

[0020] The further beneficial effects of the above are as follows: The microalgae cultivation and utilization module uses a capture device to obtain CO2 discharged from the power plant (including CO2 generated by dry solid waste incineration power generation and CO2 from other sources), as well as appropriate light, nutrients, and water, and cultivates microalgae in the photobioreactor. The photobioreactor provides a suitable environment for the growth of microalgae. The aeration device is used to introduce CO2 and provide oxygen, and the nutrient supply device provides necessary nutrients for the growth of microalgae. The cultivated microalgae are made into organic feed and supplied to the livestock and poultry breeding module.

[0021] Furthermore, in the above grain planting module, the straw is crushed and retted and returned to the field, and the livestock and poultry manure is anaerobically fermented (temperature 35 - 55 °C, cycle 15 - 30 days) to make organic fertilizers (nitrogen, phosphorus, and potassium content ≥ 5%).

[0022] Further, the above hydrogen-carbon methanol storage and transportation system includes an H2 storage device and a methanol synthesis device.

[0023] The further beneficial effects of the above are as follows: The H2 storage device is used to store H2, and the methanol synthesis device is used to synthesize methanol from H2 and CO2, store it, and transport it out through a pressure-resistant tank.

[0024] It can be seen from the above technical solutions that, compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. The present invention relates to the fields of rural solid waste treatment, H2 utilization, livestock and poultry breeding, and crop planting. It uses dry solid waste incineration power generation to capture CO2, which is used for microalgae to reduce CO2 emissions, organic fertilizers are returned to the field, and high-moisture solid waste is supercritically gasified to produce H2.

[0026] 2. The present invention incinerates and generates electricity from domestic dry garbage and off-field straw through a dry solid waste incineration power generation system, and captures CO2. The supercritical gasification system for highly water-containing solid waste performs supercritical gasification of food waste, toilet feces, livestock manure, microalgae, etc. to produce H2, which is supplied for use by local villagers' vehicles and production machinery. The microalgae cultivation and utilization module in the ecological agriculture integration system captures CO2 to cultivate microalgae, which is used to produce organic feed for the livestock and poultry breeding industry, and the surplus microalgae is used for fuel utilization; the grain planting module and the livestock and poultry breeding module return straw and livestock manure to the field. The hydrogen-carbon methanol storage and transportation system synthesizes methanol from surplus H2 and CO2. The present invention uses rural multi-source solid waste to generate electricity and produce H2 and its derivatives, simultaneously captures and utilizes the CO2 generated in the production process, and converts it into biomass resources through the microalgae cultivation and utilization system to further support the development of the livestock and poultry breeding industry. The present invention integrates agricultural waste such as straw and livestock manure, converts it into organic fertilizer through treatment and returns it to the field, improves soil fertility and promotes the increase in crop yields, not only ensures the stable supply of rural energy, improves energy utilization efficiency, but also creates economic benefits by selling methanol, promotes the development of the planting and breeding industries, and realizes the energy conversion and resource utilization of solid waste.

[0027] 3. The present invention discloses an energy supply technical solution based on the coupling of dry solid waste incineration power generation, supercritical H2 production, and the resource utilization of agricultural by-products, specifically a rural multi-source solid waste energy conversion and resource utilization system for assisting agricultural production, which integrates various new energy technologies such as dry solid waste incineration power generation, highly water-containing solid waste H2 production, and microalgae carbon fixation, realizes multi-energy complementarity and efficient utilization of energy, is deeply coupled with the agricultural circular economy, forms a closed-loop resource utilization model, converts rural solid waste into clean energy, improves the stability and reliability of energy supply, reduces the dependence on traditional fossil energy, and reduces carbon emissions. This system can also achieve the treatment of rural dry and wet solid waste, alleviate the greenhouse effect, protect the rural ecological environment, create economic benefits, improve agricultural production capacity, and promote rural economic development. In the long run, it is expected to be widely applied in rural areas, promoting the transformation of rural areas to a green, low-carbon, and circular development model, with significant economic, environmental, and social benefits.

[0028] 4. Through the treatment of rural solid waste, the present invention realizes the treatment of rural dry and wet solid waste, dry solid waste incineration power generation, and supercritical gasification of highly water-containing solid waste to produce H2. The comprehensive utilization rate of dry and wet solid waste is ≥95%, and the landfill volume is reduced by more than 80%, significantly reducing soil, water pollution, and methane emissions caused by landfill, reducing the environmental pollution of solid waste, and at the same time realizing the resource utilization of solid waste, converting solid waste into energy and useful substances.

[0029] 5. By integrating multiple energy sources, such as power generation from dry solid waste incineration, carbon sequestration by microalgae, and hydrogen production from high-moisture solid waste, etc., the present invention realizes the multi-energy complementarity of energy, improves the stability and reliability of rural energy supply. By using the surplus power for residents' living and production, the energy utilization efficiency is improved and energy waste is reduced.

[0030] 6. The present invention uses microalgae as animal feed in the livestock and poultry breeding industry, and returns straw and livestock manure to the field for food crop cultivation, which helps to improve the breeding production capacity and grain yield, and promotes the development of the rural economy. At the same time, the stable power supply provided by the system meets the electricity demand of villagers' living and production, and improves the living standards of villagers.

[0031] 7. The present invention uses the MEA chemical absorption method to capture CO2, and microalgae cultivation utilizes CO2 for carbon sequestration, reducing CO2 emissions, which is beneficial to alleviating the greenhouse effect. The reasonable treatment and utilization of solid wastes such as livestock manure reduce the pollution of water bodies and soil, and protect the rural ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the structure and process of the rural multi-source solid waste energy conversion and resource utilization system of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] Embodiment 1

[0035] The rural multi-source solid waste energy conversion and resource utilization system, as Figure 1 shown, includes a dry solid waste incineration power generation system, a high-moisture solid waste supercritical gasification system, an ecological agriculture integration system, and a hydrogen-carbon methanol storage and transportation system.

[0036] Among them, the dry solid waste incineration power generation system includes a domestic waste classification device, a solid waste incineration waste heat boiler, a power generation device, and a CO2 capture device; the domestic waste classification device includes a waste input port, an automatic sorting machine, a classified storage bin, and a waste transportation system; after the CO2 captured by the CO2 capture device is compressed and stored, it is transported to the ecological agriculture integration system through pipelines. The dry solid waste incineration power generation system regularly collects the dry domestic waste of villagers through the domestic waste classification device, and transports it and the straw removed from the fields to the dry solid waste treatment center. At the dry solid waste treatment center, the dry solid waste is classified and pretreated to remove the impurities therein. The pretreated dry solid waste is sent into the solid waste incineration waste heat boiler and incinerated under suitable conditions. The high-temperature flue gas generated by the incineration enters the waste heat boiler and exchanges heat with the water in the boiler to generate high-temperature and high-pressure steam. The steam drives the power generation device to generate electricity, and the steam after power generation can be recycled after condensation. At the same time, using the CO2 capture device, the chemical absorption method is adopted, and specifically MEA (monoethanolamine) is used as the absorbent to capture the CO2 generated by the incineration, compress and store it, and use it for microalgae cultivation. The electricity generated by the dry solid waste incineration power generation system is partially used for the supercritical gasification system of high-moisture solid waste, and the remaining electricity is supplied to the domestic and production electricity of villagers.

[0037] The supercritical gasification system of high-moisture solid waste includes a supercritical gasification reactor and a gas separation and purification device; the mixed gas containing H2 generated by the supercritical gasification reactor is purified by the gas separation and purification device and then transported to the hydrogen-carbon methanol storage and transportation system through pipelines. The supercritical gasification system of high-moisture solid waste collects perishable kitchen waste and rural toilet feces through the domestic waste classification device, and transports the remaining livestock manure and the remaining microalgae after returning to the field to the high-moisture solid waste treatment facility through pipelines or transport vehicles. First, it is pretreated to remove the large particle impurities and foreign matters therein, and the pH is adjusted, and then the organic waste is sent into the supercritical gasification reactor. In the supercritical gasification reactor, an appropriate amount of water and catalyst are added, and under the supercritical conditions of high temperature (400 - 600 °C) and high pressure (22 - 30 MPa), the solid waste undergoes a gasification reaction to generate a mixed gas such as H2, CO, and CO2. The mixed gas after the reaction passes through the gas separation and purification device, and high-purity H2 is separated by using technologies such as pressure swing adsorption and membrane separation. The H2 can be directly used for the vehicles and mechanical equipment of local villagers, and the surplus H2 is transported to the hydrogen-carbon methanol storage and transportation system, and the methanol synthesis device is used to synthesize methanol from H2 and CO2.

[0038] The ecological agriculture integrated system includes a microalgae cultivation and utilization module, a grain planting module, and a livestock and poultry breeding module; the microalgae cultivation and utilization module includes a photobioreactor, an aeration device, and a nutrient salt supply device, and the surplus microalgae are dried and then enter the supercritical gasification system for high-moisture solid waste to produce H2 by gasification; in the grain planting module, the straw is crushed and composted and returned to the field, and the livestock and poultry manure is anaerobically fermented to produce organic fertilizer. In the ecological agriculture integrated system, the photobioreactor of the microalgae cultivation and utilization module is built in a place with sufficient sunlight and convenient water source. The CO2 captured from the incineration power generation of dry solid waste and other sources of CO2 are introduced into the photobioreactor through the aeration device. At the same time, an appropriate amount of water and nutrient salts (such as nitrogen, phosphorus, potassium, etc.) are added to the photobioreactor, and a suitable lighting system is connected. Microalgae varieties suitable for the local environment and breeding conditions, such as Chlorella vulgaris, Spirulina platensis, etc., are inoculated into the photobioreactor for cultivation. During the cultivation process, the growth of microalgae is regularly monitored, and conditions such as light, temperature, and CO2 concentration are adjusted to promote the growth and carbon fixation of microalgae. When the microalgae grow to a certain stage, they are collected and processed. Part of the microalgae is anaerobically fermented to produce organic feed, which is used as animal feed for the livestock and poultry breeding industry, and the remaining microalgae can be transported to the supercritical gasification system for high-moisture solid waste for further processing.

[0039] In the ecological agriculture integrated system, the grain planting module and the livestock and poultry breeding module build fertilizer treatment facilities in rural areas to collect straw and livestock and poultry manure. For straw, it can be mechanically crushed into small sections and composted by the composting method and returned to the field, while the livestock and poultry manure is anaerobically fermented. The matured livestock and poultry manure is mixed with the crushed straw to produce organic fertilizer. During the grain crop planting season, the organic fertilizer is applied to the farmland, and the fertilization amount and fertilization time are reasonably determined according to the growth requirements of different crops and the soil fertility status to improve the soil fertility and promote the growth of crops. The straw generated from the crops is taken out of the field and used as raw materials for the dry solid waste incineration power generation system and the fertilizer utilization system again.

[0040] The hydrogen-carbon methanol storage and transportation system includes an H2 storage device and a methanol synthesis device. In the hydrogen-carbon methanol storage and transportation system, an H2 storage device, such as a high-pressure H2 storage tank, is set up in the conversion and storage station to store the surplus H2 generated by the supercritical gasification system for high-moisture solid waste to produce H2. At the same time, a methanol synthesis device is built, and H2 and CO2 are introduced into the methanol synthesis reactor in a certain proportion, and a synthesis reaction occurs under the action of a catalyst to produce methanol. The reaction conditions are a temperature of 200-300°C and a pressure of 5-10 MPa. The synthesized methanol is stored and can be transported and sold according to market demand.

[0041] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A rural multi-source solid waste energy and resource utilization system, characterized in that, It includes a dry solid waste incineration power generation system, a high-water-content solid waste supercritical gasification system, an ecological agriculture integration system, and a hydrogen-carbon methanol storage and transportation system.

2. The rural multi-source solid waste energy and resource utilization system according to claim 1, characterized in that, The dry solid waste incineration power generation system includes a domestic waste classification device, a solid waste incineration waste heat boiler, a power generation device, and a CO2 capture device.

3. The rural multi-source solid waste energy and resource utilization system according to claim 2, characterized in that, The domestic waste classification device includes a garbage feeding port, an automatic sorting machine, a classified storage bin, and a garbage conveying system.

4. A rural multi-source solid waste energy and resource utilization system according to claim 2, characterized in that, The CO2 captured by the CO2 capture device is compressed and stored and then transported to the ecological agriculture integration system through a pipeline.

5. The rural multi-source solid waste energy and resource utilization system according to claim 1, characterized in that, The high-water-content solid waste supercritical gasification system includes a supercritical gasification reactor and a gas separation and purification device.

6. The rural multi-source solid waste energy and resource utilization system according to claim 5, characterized in that, The hydrogen-containing mixed gas generated by the supercritical gasification reactor is purified by the gas separation and purification device and then transported to the hydrogen-carbon methanol storage and transportation system through a pipeline.

7. A rural multi-source solid waste energy and resource utilization system according to claim 1, characterized in that, The ecological agriculture integration system includes a microalgae cultivation and utilization module, a grain planting module, and a livestock and poultry breeding module.

8. The rural multi-source solid waste energy and resource utilization system according to claim 7, characterized in that, The microalgae cultivation and utilization module includes a photobioreactor, an aeration device, and a nutrient salt supply device. The surplus microalgae are dried and then enter the high-water-content solid waste supercritical gasification system for gasification to produce H2.

9. The rural multi-source solid waste energy and resource utilization system according to claim 7, characterized in that, In the grain planting module, the straw is crushed and composted and returned to the field, and the livestock and poultry manure is anaerobically fermented to produce organic fertilizer.

10. The rural multi-source solid waste energy and resource utilization system according to claim 1, characterized in that, The hydrogen-carbon methanol storage and transportation system includes an H2 storage device and a methanol synthesis device.

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