A high-energy fecal matter treatment system and method of use thereof

Abstract

The application discloses a high-energy treatment system for excrement and a use method thereof, and belongs to the technical field of solid waste treatment and resource utilization. The treatment system comprises a pretreatment unit, a drying unit, a low-temperature baking unit, a post-treatment unit and a waste gas treatment and energy recovery system; an integrated process of pretreatment-drying-low-temperature baking-post-treatment is adopted, high-temperature flue gas discharged from the low-temperature baking unit is used as a heat source of the drying unit, waste gas generated by the pretreatment unit, the drying unit and the low-temperature baking unit is sent into a combustion device for high-temperature combustion after being collected, the waste gas is sent into the combustion device for high-temperature combustion after being collected to realize harmlessness treatment, low-temperature baking flue gas waste heat is used for drying, energy cascade utilization is realized, and the problems of low pyrolysis efficiency, high energy consumption and serious secondary pollution of an existing excrement treatment process are solved.

Description

Technical Field

[0001] This application relates to the field of solid waste treatment and resource utilization technology, and in particular to a high-energy treatment system for manure and sewage and its usage method. Background Technology

[0002] With the large-scale and intensive development of animal husbandry, the amount of livestock and poultry manure produced has continued to increase, becoming a prominent issue affecting the quality of the ecological environment and the sustainable development of animal husbandry. Livestock and poultry manure has a high water content and is easily perishable. If not properly treated, it can cause eutrophication of water bodies through surface runoff and infiltration. Long-term application can lead to the accumulation of pollutants such as heavy metals and antibiotics in the soil. Furthermore, anaerobic fermentation can release greenhouse gases such as methane and ammonia, as well as malodorous substances, placing multiple pressures on the water, soil, and atmospheric environments. How to scientifically, efficiently, and environmentally treat livestock and poultry manure and transform it from an environmental pollutant into a renewable resource is an urgent problem to be solved in the field of agricultural environmental protection.

[0003] Currently, livestock and poultry manure treatment mainly includes anaerobic digestion, aerobic composting, and substrate utilization technologies. Anaerobic digestion technology produces biogas by degrading organic matter through microorganisms under anaerobic conditions. This biogas can be used for power generation, heating, or as vehicle fuel. The digested biogas residue and slurry are rich in nutrients and can be returned to the fields as organic fertilizer, achieving nutrient recycling. However, this technology has problems such as high investment and operating costs, strict requirements for material pretreatment, the potential for antibiotic residues to inhibit microbial activity, and the difficulty in treating biogas slurry. Its large-scale promotion and application are constrained by economic and technical conditions. Aerobic composting technology utilizes the metabolic action of aerobic microorganisms to decompose organic matter, converting manure into humic products. It can effectively kill pathogens and parasite eggs, remove odors, and the products can be used for soil improvement and horticulture. However, nitrogen is significantly lost during composting in the form of ammonia and other gases, and greenhouse gases such as nitrous oxide are emitted simultaneously, so the environmental benefits need to be improved. Substrate utilization methods, such as using manure as feed for earthworm farming or as a substrate for edible fungi cultivation, can achieve a certain degree of resource utilization, but the processing scale is generally small and it is difficult to absorb the large amount of manure generated by large-scale farms.

[0004] In recent years, low-temperature roasting technology for biomass has gradually attracted attention. This technology involves the gentle pyrolysis of biomass at relatively low temperatures and under anaerobic or low-oxygen conditions. By selectively removing oxygen-containing functional groups, it disrupts the fibrous structure of the biomass, making the material brittle and easier to grind, while simultaneously increasing energy density and bulk density, and improving the flowability and transport stability of the powder. Currently, research and application of low-temperature roasting technology mainly focus on lignocellulosic biomass such as forestry residues and agricultural straw. Research and application for raw materials like livestock and poultry manure, which are high in ash and nitrogen and have complex compositions, are still relatively limited. Directly applying existing lignocellulosic roasting processes to manure treatment often results in poor process adaptability and unstable product quality. Furthermore, the integration of existing roasting systems is generally low, leading to underutilization of energy and materials, and high system energy consumption and operating costs. The control and treatment of secondary pollutants such as waste gas and wastewater generated during the roasting process also need to be strengthened.

[0005] Therefore, how to develop an energy-efficient and low-secondary-pollution integrated treatment system for sewage has become an urgent problem to be solved. Summary of the Invention

[0006] This application provides a high-energy treatment system for manure and sewage and its usage method, the main purpose of which is to solve the problems of low pyrolysis efficiency, high energy consumption and serious secondary pollution in existing manure and sewage treatment processes.

[0007] To achieve the above objectives, according to one aspect of this application, a high-energy treatment system for sewage is provided, comprising a pretreatment unit, a drying unit, a low-temperature baking unit, a post-treatment unit, and a waste gas treatment and energy recovery system; the discharge end of the pretreatment unit is connected to the feed end of the drying unit, the discharge end of the drying unit is connected to the feed end of the low-temperature baking unit, and the discharge end of the low-temperature baking unit is connected to the feed end of the post-treatment unit; the flue gas outlet of the low-temperature baking unit is connected to the heat source inlet of the drying unit; the air inlet of the waste gas treatment and energy recovery system is connected to the waste gas outlets of the pretreatment unit, the drying unit, and the low-temperature baking unit, respectively, and the air outlet of the waste gas treatment and energy recovery system is connected to a combustion device for high-temperature combustion treatment of the waste gas.

[0008] Furthermore, the drying unit is a drying oven, and the drying oven is equipped with a lifting plate structure inside.

[0009] Furthermore, the low-temperature baking unit includes a sealed cavity, an inert gas replacement system, a segmented heating system, a material conveying system, a discharge system, and a temperature monitoring system; the material conveying system is a rotary drum structure with adjustable speed.

[0010] Furthermore, the segmented heating system is divided into multiple independent heating sections along the material flow direction; the multiple independent heating sections include a light baking zone, a medium baking zone, and a heavy baking zone, the temperature of the light baking zone is 220-260℃, the temperature of the medium baking zone is 290-310℃, and the temperature of the heavy baking zone is 330-350℃.

[0011] Furthermore, the post-processing unit sequentially includes a crushing device, a sand removal device, and a separation device.

[0012] Furthermore, the pretreatment unit is a floor-heated dehydration warehouse, including the warehouse body, floor heating system, ventilation system, and temperature and humidity monitoring system.

[0013] According to a second aspect of this application, a method of using a high-energy treatment system for sewage is provided, wherein the method of use is carried out within the aforementioned high-energy treatment system for sewage; wherein the method of use includes the following steps: S1. Pretreatment: The sewage is sent to the pretreatment unit for low-temperature dehydration; S2. Drying: The pretreated material is sent to the drying unit for drying to obtain dried biomass material. S3. Baking: The dried biomass material is fed into a low-temperature baking unit for segmented heating and baking to obtain baked biomass material. S4. Post-processing: The biomass baking material is fed into the post-processing unit, and after crushing, sand removal and separation, the finished product is obtained.

[0014] Furthermore, in step S1, the low-temperature dehydration process is carried out at a temperature below 50°C until the moisture content of the material is 45%-55%.

[0015] Furthermore, the segmented baking in step S3 proceeds through three stages: a light baking stage at 220-260℃ with a dwell time of 8-12 minutes; a medium baking stage at 290-310℃ with a dwell time of 15-20 minutes; and a heavy baking stage at 330-350℃ with a dwell time of 10-15 minutes.

[0016] Furthermore, the method of use also includes waste gas treatment and energy recovery steps: all waste gases generated in the pretreatment, drying and baking stages are collected and sent to the combustion device for high-temperature combustion treatment; the high-temperature flue gas discharged from the low-temperature baking unit is used as the drying heat source of the drying unit.

[0017] The beneficial effects of this application are as follows: The high-energy treatment system for manure and wastewater provided in this application and its usage method adopt an integrated process of drying and baking to achieve comprehensive and cascaded utilization of energy. The pretreatment stage involves low-temperature dehydration, while the drying stage utilizes the high-temperature flue gas discharged from the low-temperature baking unit as a heat source. Waste gas generated by each unit is collected and sent to a combustion device for high-temperature combustion, achieving harmless treatment of the waste gas. The high-temperature flue gas discharged from the low-temperature baking unit serves as a heat source for the drying unit, achieving cascaded utilization of energy, effectively reducing the overall energy consumption of the system and improving operational economy.

[0018] This application achieves gradient heating baking through a segmented heating system, precisely controlling the temperature according to the pyrolysis characteristics of different organic components in the sewage, realizing the graded and orderly pyrolysis of each component, and effectively improving pyrolysis efficiency and product quality.

[0019] This application processes manure through pretreatment, drying, and low-temperature baking, significantly increasing the energy density of biomass and producing renewable biomass green fuel. This fuel can be used as an alternative fuel for industries such as power and coal chemical, realizing the resource utilization of manure, turning waste into treasure, and has good economic and environmental benefits.

[0020] This application adopts a closed-loop treatment mode of waste gas collection and combustion. All waste gas generated in the pretreatment, drying and baking stages is collected through closed pipelines and sent to the combustion device for high-temperature combustion, which completely solves the problem of the emission of harmful gases such as ammonia and sulfides during the treatment of fecal waste. After the fecal waste is treated with low-temperature baking, pathogens are effectively inactivated, avoiding secondary pollution. The entire process has no wastewater discharge, realizing full-process control of pollutants, which is clean and environmentally friendly. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the high-energy treatment system for fecal waste provided in this application; Figure 2 This is a schematic diagram of the rotary drying oven structure provided in this application; Figure 3 This is a schematic diagram of the low-temperature baking unit structure provided in an embodiment of this application. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] Traditional manure treatment technologies suffer from problems such as low pyrolysis efficiency, high energy consumption, and severe secondary pollution. Pretreatment, drying, and pyrolysis processes are often separated, lacking effective energy integration and material coordination, resulting in high overall system energy consumption and low thermal utilization. Furthermore, harmful gases such as ammonia, hydrogen sulfide, and volatile organic compounds generated during manure treatment, if emitted directly without effective treatment, cause severe air pollution and foul odors. In addition, existing processes generally suffer from poor process adaptability, unstable product quality, and low resource utilization for raw materials like livestock and poultry manure, which are high in ash and nitrogen and have complex compositions. Therefore, this application develops a novel high-energy manure treatment system and its application method. Through system integration design and energy cascade utilization, it aims to improve the resource utilization efficiency of manure, reduce system energy consumption, and minimize secondary pollution.

[0025] According to one aspect of this application, a high-energy treatment system for sewage is provided, comprising a pretreatment unit 100, a drying unit 200, a low-temperature baking unit 300, a post-treatment unit 400, and a waste gas treatment and energy recovery system 500; the discharge end of the pretreatment unit 100 is connected to the feed end of the drying unit 200, the discharge end of the drying unit 200 is connected to the feed end of the low-temperature baking unit 300, and the discharge end of the low-temperature baking unit 300 is connected to the feed end of the post-treatment unit 400; the flue gas outlet of the low-temperature baking unit 300 is connected to the heat source inlet of the drying unit 200; the air inlet of the waste gas treatment and energy recovery system is connected to the waste gas outlets of the pretreatment unit 100, the drying unit 200, and the low-temperature baking unit 300, respectively, and the air outlet of the waste gas treatment and energy recovery system is connected to a combustion device for high-temperature combustion treatment of the waste gas.

[0026] This application employs an integrated process system encompassing pretreatment, drying, low-temperature baking, and post-treatment. Through a system integration design that connects the material pathways of each unit in series, integrates the heat circulation pathways, and establishes a closed-loop waste gas treatment pathway, it achieves the reduction, harmlessness, and energy recovery of manure. Compared to traditional manure treatment systems, this application applies low-temperature baking technology to the field of manure treatment. By using a staged heating method to gradually pyrolyze the materials, it improves pyrolysis efficiency and product quality. Simultaneously, the waste heat from the baking flue gas is used for drying, achieving multi-stage energy recovery and significantly reducing system energy consumption. The waste gas is collected in a closed loop and then combusted at high temperature, completely solving the problem of harmful gas escape and achieving clean treatment. This application's system features high integration, high automation, and stable and reliable operation, making it suitable for centralized manure treatment in large-scale farms, and offering significant economic and environmental benefits.

[0027] In some specific embodiments, the drying unit 200 is a drying furnace, and the drying furnace is equipped with a lifting plate structure inside. For example, the drying furnace can be a rotary drum drying furnace, including a cylinder 210, lifting plates 220, a feed inlet 230, a discharge outlet 240, a flue gas inlet 250, and a flue gas outlet 260; the cylinder is rotatable, and the lifting plates are evenly distributed on the inner wall of the cylinder for turning the material. Using a rotary drum drying furnace with a lifting plate structure allows the material to be continuously turned over during the drying process, resulting in more uniform heating, preventing material agglomeration, and improving drying efficiency and uniformity; the rotary drum drying furnace has a simple structure, reliable operation, and large processing capacity, making it suitable for large-scale manure treatment. The axis of the rotary drum drying furnace can be slightly inclined, with material entering from the high end and exiting from the low end. Continuous conveying is achieved through the rotation of the cylinder and the turning action of the lifting plates, while simultaneously ensuring full contact and heat exchange with the high-temperature flue gas to complete the drying process.

[0028] In some specific embodiments, the low-temperature baking unit 300 includes a sealed cavity, an inert gas replacement system, a segmented heating system, a material conveying system, a discharge system, and a temperature monitoring system; the material conveying system is a rotary drum structure with adjustable speed. The sealed cavity combined with the inert gas replacement system ensures a low-oxygen environment during the baking process, preventing material oxidation and improving carbon retention and product calorific value; the adjustable-speed rotary drum structure allows for control of material residence time through speed adjustment, adapting to different raw materials and product requirements. The low-temperature baking unit 300 is the functional unit of the entire system, undertaking key functions such as material pyrolysis and quality improvement, energy density enhancement, and pathogen inactivation. Its operational stability and pyrolysis efficiency directly affect the final product quality and the overall system energy efficiency.

[0029] In some specific embodiments, the sealed cavity is composed of a rotary feeding mechanism, a multi-layer rotary equalizing cylinder, and a rotary discharge smoke-blocking device connected in series to form a closed pyrolysis space. The multi-layer rotary equalizing cylinder is a cylindrical body with 1-3 layers arranged coaxially, and each layer has lifting plates evenly distributed on its sidewall to ensure uniform heating and movement of the material. For example, the multi-layer rotary equalizing cylinder is a cylindrical body with 3 layers arranged coaxially, and each layer has lifting plates and sieve holes evenly distributed on its sidewall, with the sieve holes having a diameter of 8mm. The rotational speed of the multi-layer rotary equalizing cylinder is 5-8 r / min, for example, any value among 5 r / min, 6 r / min, 7 r / min, and 8 r / min, or any range between two values, such as 6 r / min. The multi-layer rotating uniform material distribution cylinder structure increases the heating area of ​​the material and extends its residence time, resulting in more complete pyrolysis. The three-layer coaxial cylinder structure, coupled with a rotation speed of 5-8 r / min, facilitates the penetration of hot flue gas, enhancing gas-solid heat transfer. It also allows the material to fall layer by layer through the screen holes during tumbling, achieving uniform material conveying and mixing, preventing localized overheating or uneven heating, and improving the stability and consistency of product quality. The rotating feeding mechanism and rotating discharge smoke-blocking device enable continuous feeding and discharging while effectively preventing outside air from entering the chamber, maintaining a low-oxygen environment and ensuring the safe and stable operation of the pyrolysis process.

[0030] In some specific embodiments, the inert gas replacement system includes a nitrogen storage tank, a gas pipeline, and a gas distributor. The gas distributor is located at the top of the sealed cavity, and the gas pipeline is equipped with a flow regulating valve. By introducing nitrogen into the sealed cavity, the oxygen content inside the cavity is controlled to be ≤0.5%. Using an inert gas replacement system ensures an oxygen-free environment during the baking process, preventing material oxidation and improving carbon retention and product calorific value. Nitrogen, as an inert protective gas, is chemically stable and will not react with materials or introduce impurities. The uniform gas distribution via the top gas distributor ensures a consistent oxygen content throughout the cavity, preventing excessively high local oxygen concentrations that could lead to material oxidation and combustion. When starting the system, nitrogen is first introduced to replace the air in the cavity. Once the oxygen content drops to the set value, material is fed in for operation. During operation, nitrogen is continuously replenished to maintain a slight positive pressure inside the cavity, preventing the infiltration of outside air.

[0031] In some specific embodiments, the segmented heating system is divided into multiple independent heating sections along the material flow direction. These independent heating sections include a light-roasting zone, a medium-roasting zone, and a heavy-roasting zone. The temperature of the light-roasting zone is 220-260℃, for example, any value or a range between 220℃, 230℃, 240℃, 250℃, and 260℃. The temperature of the medium-roasting zone is 290-310℃, for example, any value or a range between 290℃, 295℃, 300℃, 305℃, and 310℃. The temperature of the heavy-roasting zone is 330-350℃, for example, any value or a range between 330℃, 335℃, 340℃, 345℃, and 350℃. This three-stage gradient heating method allows different components in the material to fully pyrolyze within their respective suitable temperature ranges, avoiding the problem of insufficient or excessive decomposition of some components under a single constant-temperature mode, thus improving pyrolysis efficiency and product quality. Manure contains various organic components such as cellulose, hemicellulose, lignin, protein, and fat. The pyrolysis temperature ranges and characteristics of these components vary considerably. Hemicellulose decomposes at relatively low temperatures, cellulose requires moderate temperatures, while lignin and protein require even higher temperatures for complete pyrolysis. The three-stage gradient heating process addresses this characteristic, enabling the orderly pyrolysis of various organic components within their respective optimal temperature ranges, maximizing deoxygenation, quality improvement, and energy enrichment.

[0032] In some specific embodiments, the segmented heating system includes a burner, heat conduction pipes, and an insulation layer. The burner is uniformly arranged along the axial direction of the sealed cavity to ensure that the cylinder temperature is within the pyrolysis temperature range of 220-350℃. The heat conduction pipes are arranged close to the inner wall of the cavity, and the insulation layer is wrapped around the outside of the cavity to reduce heat loss. The segmented heating system allows for independent control of different temperature zones, meeting the process requirements of gradient heating. Each heating section is equipped with an independent burner and temperature monitoring point, and precise temperature control of each zone is achieved by adjusting the heat output of the burner. The heat conduction pipes, arranged close to the inner wall of the cavity, can evenly transfer the heat generated by combustion to the inside of the cavity, avoiding excessively high or low local temperatures. The external insulation layer uses high-temperature resistant insulation material to effectively reduce heat loss from the cavity surface and improve thermal energy utilization efficiency.

[0033] In some specific embodiments, the discharge system includes a screw conveyor and a drive motor. The screw conveyor has a sealed cavity outside for water-cooling the high-temperature carbonized materials. This screw conveyor combined with water cooling allows for continuous discharge while rapidly reducing the material temperature, preventing oxidation after discharge and ensuring product quality. The material temperature after low-temperature baking is relatively high; direct contact with air can easily lead to oxidation or even spontaneous combustion. The water-cooled cavity outside the screw conveyor uses circulating cooling water to quickly remove heat from the material, lowering its temperature below a safe range. Simultaneously, the sealed structure of the screw conveyor effectively isolates the material from air, preventing oxidation through contact with oxygen during transport. The water-cooled material temperature generally drops below 60°C, allowing it to safely proceed to subsequent post-processing steps.

[0034] In some specific embodiments, the temperature monitoring system includes several thermocouples and a temperature display screen. The thermocouples are evenly distributed across various temperature zones within the sealed cavity, collecting real-time temperature data and feeding it back to the temperature display screen to achieve closed-loop temperature control. The temperature monitoring system ensures precise temperature control in each zone, guaranteeing process stability and consistent product quality. The thermocouples are evenly distributed along the cavity axis at key locations in each heating section, monitoring temperature changes in each area in real time. After the temperature data is transmitted to the control system, it is compared with the set temperature, and the burner's heat output is automatically adjusted using control algorithms such as PID control to stabilize the temperature in each zone within the set range. The temperature monitoring system also features an over-temperature alarm function; when the temperature in a certain zone exceeds a safety threshold, an alarm is automatically triggered, and corresponding protective measures are taken to ensure safe equipment operation.

[0035] In some specific embodiments, the post-processing unit 400 sequentially includes a crushing device, a sand removal device, and a separation device. Crushing, sand removal, and separation can remove impurities such as sand and gravel from the material, obtaining a powdered product with uniform quality. Optionally, the post-processing unit 400 also includes a granulation device to form the powdered material into granular finished products. Granulation can increase the bulk density of the product, facilitating storage and transportation. The crushing device crushes the baked lumpy material to a certain particle size range, facilitating subsequent sand removal and separation processing; the sand removal device uses density differences to remove inorganic impurities such as sand and gravel mixed in the material, improving the ash quality of the product; the separation device classifies the material by means of sieving or air classification, obtaining a powdered product with uniform particle size. The granulation device can process the powdered product into pellet fuel of different specifications according to market demand. Pellet fuel has advantages such as high bulk density, good flowability, convenient storage and transportation, and stable combustion, and has a wider range of applications.

[0036] In some specific embodiments, the pretreatment unit 100 is a floor-heated dehydration chamber, including a main chamber body, a floor heating system, a ventilation system, and a temperature and humidity monitoring system. Using a floor-heated dehydration chamber ensures uniform heating and controllable temperature, enabling gentle dehydration of manure and avoiding organic matter degradation and nitrogen loss caused by high temperatures. The floor heating system radiates heat into the chamber through heating pipes buried under the floor, ensuring uniform heating of the manure from the bottom up, allowing moisture to evaporate slowly. This bottom-up heating method facilitates the upward migration of moisture along the material pores and its escape from the surface, resulting in high dehydration efficiency and preventing material caking. The ventilation system promptly removes humid air from the chamber, maintaining a low relative humidity and enhancing surface moisture evaporation. The temperature and humidity monitoring system monitors changes in temperature and humidity in the chamber in real time, providing a basis for adjusting process parameters.

[0037] In some specific embodiments, the waste gas treatment and energy recovery system 500 includes a waste gas collection pipe, a combustion device, and a heat recovery device. The waste gas collection pipe is connected to the waste gas outlets of the pretreatment unit 100, the drying unit 200, and the low-temperature baking unit 300, respectively. The combustion device is used to burn the waste gas, and the heat recovery device is used to recover the heat generated by combustion. Adopting a closed-loop "collection-combustion" treatment mode for waste gas can completely solve the problem of the escape of harmful gases such as ammonia and sulfides, while simultaneously recovering the heat generated by the combustion of waste gas, achieving cascaded energy utilization. The waste gas generated by each unit is uniformly collected through a closed collection pipe and then sent to the combustion device, where it is completely combusted and decomposed under high-temperature conditions. Harmful components such as ammonia, hydrogen sulfide, and volatile organic compounds are completely oxidized and decomposed into harmless substances such as carbon dioxide, water, nitrogen, and sulfur dioxide, achieving harmless treatment of the waste gas. The high-temperature flue gas generated by combustion carries a large amount of heat, which is recovered and utilized through the heat recovery device, further improving the energy utilization efficiency of the system.

[0038] In some specific embodiments, the exhaust gas treatment and energy recovery system 500 is connected to a combustion device at its outlet. The heat generated by the combustion device is recycled to the pretreatment unit 100 and the drying unit 200, respectively. The high-temperature flue gas generated by the combustion device has a high temperature and heat content. Through reasonable heat distribution and tiered utilization, it can provide heat sources for both the pretreatment unit 100 and the drying unit 200. Specifically, the high-temperature flue gas discharged from the combustion device can first be introduced into the flue gas inlet of the drying unit 200 as the main heat source for the drying process, using the sensible heat of the high-temperature flue gas to heat and dry the materials. After heat exchange in the drying unit 200, the flue gas, whose temperature has decreased, can continue to be introduced into the underfloor heating system of the pretreatment unit 100, using the waste heat of the flue gas to provide the heat required for low-temperature dehydration in the pretreatment warehouse. This two-stage heat recovery method of "drying the high-temperature flue gas first and then preheating the low-temperature waste gas" realizes the tiered utilization of energy, making full use of the heat generated by combustion, significantly reducing the system's dependence on external energy sources, and improving overall energy efficiency. The heat distribution of the combustion device can be achieved by adjusting the valve opening on the flue gas duct. The flow ratio of the two flue gas ducts can be flexibly adjusted according to the actual heat load requirements of the pretreatment and drying processes to ensure a balance between heat supply and demand in each process.

[0039] According to another aspect of this application, a method of using the above-mentioned high-energy treatment system for sewage is provided, comprising the following steps: S1. Pretreatment: The sewage is sent to the pretreatment unit 100 for low-temperature dehydration; S2. Drying: The pretreated material is sent to the drying unit 200 for drying to obtain dried biomass material. S3. Baking: The dried biomass material is fed into a low-temperature baking unit 300 for segmented heating and baking to obtain baked biomass material. S4. Post-processing: The biomass baking material is fed into the post-processing unit 400, and after crushing, sand removal and separation, the finished product is obtained.

[0040] In some specific embodiments, in step S1, the low-temperature dehydration process is carried out at a temperature below 50°C, dehydrating the material to a moisture content of 45%-55%, such as any value or a range between 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, and 55%. For example, underfloor heating can be used for low-temperature dehydration, controlling the relative humidity below 50%RH. Using low-temperature underfloor heating dehydration allows the moisture in the manure to evaporate slowly, preventing crusting on the material surface. Simultaneously, the low temperature reduces the degradation of organic matter and nitrogen loss, providing a good material foundation for subsequent processing. The pretreatment stage is the first step in the entire process, primarily aimed at removing most of the free water from the manure, reducing the moisture content from the original 60%-80% to approximately 50%, providing raw materials with suitable moisture content and stable properties for subsequent drying and baking processes. Under low-temperature dehydration conditions, the organic matter in the manure is less prone to degradation, and the retention rate of nutrients such as nitrogen is high, which is beneficial for subsequent pyrolysis upgrading and improving the product's calorific value. During the pretreatment process, the material should be turned over regularly to prevent the surface of the material from hardening and affecting the evaporation of internal moisture, while also ensuring that the material is dehydrated evenly.

[0041] In some specific embodiments, in step S2, the drying is carried out in a rotary drying oven at a temperature of 100-150℃, such as any value or a range between 100℃, 110℃, 120℃, 130℃, 140℃, and 150℃. The heat source for drying is the high-temperature flue gas discharged from the low-temperature baking unit 300, with a flue gas temperature ≥100℃ and a flue gas flow rate of 0.8-1.0 m³ / h, for example, 0.9 m³ / h. Utilizing the high-temperature flue gas discharged from the low-temperature baking unit 300 as the heat source for drying allows for the recovery and utilization of waste heat from the flue gas, reducing additional energy consumption, lowering operating costs, and improving the energy efficiency of the system. The drying process is an intermediate step connecting pretreatment and baking, and its main function is to further reduce the moisture content of the material from about 50% to 20%-30%, so that the material reaches a suitable moisture content for baking. Utilizing the high-temperature flue gas discharged from the baking unit directly as the drying heat source eliminates the need for additional coal-fired or gas-fired boilers, saving on equipment investment and reducing operating energy consumption. This is a crucial component of the energy cascade utilization design in this application. The lifting plate structure inside the rotary dryer continuously turns the material, ensuring full contact between the material and the high-temperature flue gas, enhancing heat and mass transfer, and improving drying efficiency and uniformity.

[0042] In some specific embodiments, the segmented heating and baking in step S3 sequentially goes through three stages: a light baking stage with a temperature of 220-260℃ and a dwell time of 8-12 min, such as any value or a range between 8 min, 9 min, 10 min, 11 min, and 12 min; a medium baking stage with a temperature of 290-310℃ and a dwell time of 15-20 min, such as any value or a range between 15 min, 16 min, 17 min, 18 min, 19 min, and 20 min; and a heavy baking stage with a temperature of 330-350℃ and a dwell time of 10-15 min, such as any value or a range between 10 min, 11 min, 12 min, 13 min, 14 min, and 15 min. The light baking stage primarily removes residual moisture from the material and initiates the pyrolysis of some easily decomposable components, preparing for subsequent deep baking. The medium baking stage is the main pyrolysis stage, removing a large number of oxygen-containing functional groups and significantly increasing the material's energy density. The heavy baking stage further pyrolyzes the material, increasing the degree of carbonization and further improving the product's stability and calorific value. Three-stage gradient heating baking is a key process in this application. By precisely controlling the temperature and residence time at each stage, different organic components in the manure are decomposed in an orderly manner according to their pyrolysis characteristics, achieving selective deoxygenation, quality improvement, and energy enrichment. After the three-stage baking process, the material's fibrous structure is fully destroyed, making it brittle and easy to grind, significantly increasing its energy density. Simultaneously, pathogens and parasite eggs are completely inactivated, significantly improving the product's hygiene and safety.

[0043] In some specific embodiments, in step S3, the segmented heating and baking is carried out under normal pressure and low oxygen conditions, with a baking temperature of 200-360℃. During baking, the material is slowly and uniformly stirred, resulting in a pyrolysis and embrittlement reaction that destroys the fiber structure, deoxygenates and sterilizes, and increases energy density. Low-temperature baking under low oxygen conditions avoids oxidation and combustion of the material, ensuring carbon retention and increasing the product's calorific value. Slow and uniform stirring ensures even heating of the material, guaranteeing stable product quality. Normal pressure operation reduces the requirements for equipment pressure resistance, simplifies equipment structure, and lowers investment costs and operational risks. The low-oxygen environment is achieved through inert gas replacement, effectively preventing material oxidation and ensuring the carbon retention and calorific value of the pyrolysis products. Continuous slow turning of the material during baking ensures uniform heating, preventing localized overheating and uneven quality, and promotes the timely escape of volatiles generated during pyrolysis from the material surface, enhancing the pyrolysis reaction.

[0044] In some specific embodiments, the method further includes waste gas treatment and energy recovery steps: all waste gases generated in the pretreatment, drying, and baking stages are collected and sent to a combustion device for high-temperature combustion treatment; the high-temperature flue gas discharged from the low-temperature baking unit 300 serves as the drying heat source for the drying unit 200. Adopting a closed-loop waste gas treatment mode can completely solve the problem of the escape of harmful gases such as ammonia and sulfides, while simultaneously recovering the heat generated by waste gas combustion, achieving cascaded energy utilization, and improving the system's energy efficiency. Waste gas treatment and energy recovery are important supporting links in the process of this application. On the one hand, high-temperature combustion thoroughly decomposes harmful components in the waste gas, achieving clean emissions; on the other hand, heat recovery and utilization reduce system energy consumption and improve economic efficiency. The closed-loop collection and centralized combustion mode of the entire waste gas process eliminates the unorganized escape of harmful gases, fundamentally solving the problem of odor nuisance from sewage treatment plants; the heat generated by combustion is reused in stages to provide heat sources for the drying and pretreatment processes, significantly increasing the system's energy self-sufficiency rate and significantly reducing operating costs.

[0045] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0046] All raw materials used in the embodiments of this application are existing technologies.

[0047] Example 1 This embodiment provides a high-energy treatment method for fecal waste, the specific steps of which are as follows: (1) Pretreatment: Take cow manure raw material with a moisture content of about 75% and send it to a floor-heated dehydration warehouse for low-temperature dehydration; control the warehouse temperature to 45℃ and the relative humidity to 45%RH, and dehydrate the material to a moisture content of about 50%; the water vapor, ammonia, sulfides and other waste gases volatilized during the pretreatment process are collected through the ventilation system and then transported to the combustion device 600 for combustion; the material is turned over regularly to ensure uniform dehydration.

[0048] (2) Drying: The pretreated material is conveyed to a rotary drum dryer via a belt conveyor. The dryer is equipped with a lifting plate 220 structure. The high-temperature flue gas discharged from the low-temperature baking unit 300 is used as a heat source. The flue gas temperature is about 120℃ and the flue gas flow rate is 0.9m³ / h. 3 / h; drying temperature is 120℃, drying until the material moisture content is about 25%.

[0049] (3) Low-temperature baking: The dried material is sent to the low-temperature baking unit 300 and baked in stages under normal pressure and anaerobic conditions. The rotation speed of the baking unit is 6 r / min. Light baking stage: temperature 240℃, oxygen content 0.8%, dwell time 10min; Medium baking stage: temperature 300℃, oxygen content 0.4%, dwell time 18min; Heavy baking stage: temperature 340℃, oxygen content ≤0.1%, dwell time 12min.

[0050] (4) Post-processing: The baked material is crushed, sand removed and separated to obtain powdered high-energy carbonized material; some of the powdered material is granulated into granular finished product.

[0051] (5) Waste gas treatment and energy recovery: All waste gas generated in the pretreatment, drying and baking stages is collected through a closed pipeline and sent to the combustion device at a high temperature of 600 to achieve closed-loop treatment and harmlessness of waste gas.

[0052] Example 2 This embodiment provides a high-energy treatment method for manure, the specific steps of which are basically the same as those in Embodiment 1, the difference being the baking temperature parameter: Light baking stage: temperature 220℃, dwell time 12min; Medium baking stage: temperature 290℃, time 20min; Heavy baking stage: temperature 330℃, dwell time 15min.

[0053] Example 3 This embodiment provides a high-energy treatment method for manure, the specific steps of which are basically the same as those in Embodiment 1, the difference being the baking temperature parameter: Light baking stage: temperature 260℃, time 8 minutes; Medium baking stage: temperature 310℃, time 15min; Heavy baking stage: temperature 350℃, dwell time 10min.

[0054] Comparative Example 1 This comparative example provides a method for treating fecal waste, the specific steps of which are basically the same as those in Example 1, the difference being that baking adopts a single constant temperature mode and does not involve segmented gradient heating: Baking temperature: 270℃, constant temperature, total dwell time: 40 minutes.

[0055] Table 1 Performance Comparison of Examples 1-3 and Comparative Example 1

[0056] As can be seen from Table 1, compared with Comparative Example 1, the products obtained in Examples 1-3 all showed significant improvements in terms of low heating value, grindability index, bulk density and environmental indicators.

[0057] Specifically, the lower heating value of the finished products obtained in the examples was significantly increased, indicating that the staged heating and baking can effectively promote the thermal deoxygenation and energy enrichment of organic components in manure, thereby significantly improving the fuel performance of the products.

[0058] In terms of structural performance, the grindability index of the embodiment is significantly higher than that of the comparative example, indicating that the internal fiber structure of the material is effectively destroyed and the degree of embrittlement is increased after the process of this application, which is beneficial to subsequent crushing and grinding processing; at the same time, the bulk density is increased, indicating that the particle structure of the material is more compact, which is beneficial to storage and transportation.

[0059] Regarding resource conversion efficiency, Comparative Example 1, due to its use of a single isothermal pyrolysis method, exhibits a relatively weak degree of pyrolysis, with some unreacted organic components remaining in solid form, thus demonstrating a high mass yield. In contrast, the Example promotes the full pyrolysis reaction through segmented gradient heating, further converting some organic components into gaseous or liquid products, resulting in a slightly lower mass yield. However, this process is accompanied by a significant increase in lower heating value, indicating that the material has been effectively converted into high-energy fuel.

[0060] In terms of environmental performance, the volatile organic compound collection rate and pathogen inactivation rate of the embodiment were significantly higher than those of the comparative example, indicating that the present application can effectively reduce the risk of pollutant escape and achieve a better harmless treatment effect through the closed collection-combustion system and the staged pyrolysis process.

[0061] In summary, this application achieves high-energy conversion and clean utilization of manure through the synergistic effect of pretreatment, drying, segmented low-temperature baking, and post-treatment, and has good industrial application value.

[0062] It should be understood that this application is not limited to the processes and structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A high-energy treatment system for fecal waste, characterized in that, It includes a pretreatment unit, a drying unit, a low-temperature baking unit, a post-treatment unit, and a waste gas treatment and energy recovery system; The discharge end of the pretreatment unit is connected to the feed end of the drying unit, the discharge end of the drying unit is connected to the feed end of the low-temperature baking unit, and the discharge end of the low-temperature baking unit is connected to the feed end of the post-treatment unit. The flue gas outlet of the low-temperature baking unit is connected to the heat source inlet of the drying unit; the air inlet of the waste gas treatment and energy recovery system is connected to the waste gas outlets of the pretreatment unit, the drying unit, and the low-temperature baking unit, respectively; the air outlet of the waste gas treatment and energy recovery system is connected to a combustion device, which is used to perform high-temperature combustion treatment on the waste gas.

2. The processing system according to claim 1, characterized in that, The drying unit is a drying oven, and the drying oven is equipped with a lifting plate structure inside.

3. The processing system according to claim 1, characterized in that, The low-temperature baking unit includes a sealed cavity, an inert gas replacement system, a segmented heating system, a material conveying system, a discharge system, and a temperature monitoring system; the material conveying system is a rotary drum structure with adjustable speed.

4. The processing system according to claim 3, characterized in that, The segmented heating system is divided into multiple independent heating sections along the material flow direction; the multiple independent heating sections include a light baking zone, a medium baking zone, and a heavy baking zone, the temperature of the light baking zone is 220-260℃, the temperature of the medium baking zone is 290-310℃, and the temperature of the heavy baking zone is 330-350℃.

5. The processing system according to claim 1, characterized in that, The post-processing unit includes, in sequence, a crushing device, a sand removal device, and a separation device.

6. The processing system according to claim 1, characterized in that, The pretreatment unit is a floor-heated dehydration warehouse, which includes the warehouse body, floor heating system, ventilation system and temperature and humidity monitoring system.

7. A method of using the processing system according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Pretreatment: The sewage is sent to the pretreatment unit for low-temperature dehydration; S2. Drying: The pretreated material is sent to the drying unit for drying to obtain dried biomass material. S3. Baking: The dried biomass material is fed into a low-temperature baking unit for segmented heating and baking to obtain baked biomass material. S4. Post-processing: The biomass baking material is fed into the post-processing unit, and after crushing, sand removal and separation, the finished product is obtained.

8. The method of use according to claim 7, characterized in that, In step S1, the low-temperature dehydration process is carried out at a temperature below 50°C until the moisture content of the material is 45%-55%.

9. The method of use according to claim 7, characterized in that, Step S3 involves segmented baking through three stages: light baking at 220-260℃ for 8-12 minutes; medium baking at 290-310℃ for 15-20 minutes; and heavy baking at 330-350℃ for 10-15 minutes.

10. The method of use according to claim 7, characterized in that, The method of use also includes waste gas treatment and energy recovery steps: all waste gases generated in the pretreatment, drying and baking stages are collected and sent to the combustion device for high-temperature combustion treatment; the high-temperature flue gas discharged from the low-temperature baking unit is used as the drying heat source of the drying unit.

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