Biological drying bin and treatment process thereof

Abstract

The invention relates to a biological drying bin treatment process, which comprises the steps of raw material pretreatment, biological drying, product treatment, wastewater treatment and deodorization treatment, and specifically comprises the following steps: mixing organic sludge with agricultural and forestry wastes, adding a special sludge biological drying agent, adjusting the carbon nitrogen ratio and the water content, and feeding into a biological drying bin; the method comprises the following steps: heating to 70-85 DEG C within 12-24 hours by utilizing the synergistic effect of medium-high temperature strong aerobic bacteria and a biocatalyst, and drying for 10-16 days, so that the water content of the sludge is reduced from 60% to 25-30%; over 80% of deodorization is realized by adopting a dual deodorization strategy of'source control and tail end purification ', and zero emission is realized by wastewater reflux treatment. The biological drying bin is composed of civil engineering, a bin body, aeration, drying agent addition and a tail gas treatment system, the structural design is optimized, and the operation efficiency is high. The method effectively solves the problems of serious odor production, low dehydration efficiency and the like in the traditional technology, and has remarkable environment-friendly and economic values. The invention further discloses the biological drying bin.

Description

Technical Field

[0001] This invention relates to the field of sludge treatment technology, specifically a process and biological drying chamber for the rapid treatment of odor-generating and dewatering sludge through biological drying. It is applicable to the harmless, volume-reduced, and resource-based treatment of organic sludge such as municipal sludge, kitchen waste, garden waste, agricultural and forestry waste, and industrial organic solid waste. Background Technology

[0002] Accelerated global urbanization has driven a year-on-year increase in wastewater treatment volume, resulting in a significant rise in sludge production as a byproduct of wastewater treatment. Improperly treated sludge contains pollutants such as heavy metals, pathogenic microorganisms, and persistent organic matter. Direct discharge or disposal of such sludge can easily cause secondary pollution of soil, water, and air, threatening ecological security and public health.

[0003] Traditional sludge treatment technologies mainly include thickening, mechanical dewatering, and thermal drying. These technologies generally suffer from high energy consumption, expensive operating costs, and large carbon emissions, significantly increasing the economic and environmental burden of sludge treatment. Biological sludge drying technology relies on the bioheat generated by microbial degradation of organic matter, combined with forced ventilation to promote moisture evaporation and achieve sludge drying. It boasts advantages such as low energy consumption, low operating costs, and resource recovery potential, making it a research hotspot in the field of sludge treatment. This technology can also kill pathogens through high-temperature effects and improve the physicochemical properties of sludge, laying the foundation for subsequent resource utilization.

[0004] However, traditional sludge biological drying processes still face many technical bottlenecks in practical industrial applications, specifically: 1) Odor problem is prominent: During the anaerobic decomposition of organic matter by microorganisms, malodorous gases such as ammonia, hydrogen sulfide, and volatile organic compounds (VOCs) are produced, which not only pollute the surrounding atmospheric environment, but also harm the health of workers and nearby residents, and are prone to causing environmental disputes. 2) Insufficient dewatering efficiency: Existing technologies such as turning and turning, membrane fermentation, and trough fermentation are insufficient to reduce the sludge moisture content to below 40%, which limits the application of sludge in high-value-added resource utilization fields such as biomass fuel. 3) Poor operational stability: Ventilation strategy has a significant impact on drying effect. Insufficient ventilation can easily lead to increased anaerobic fermentation and odor production, while excessive ventilation can easily cause a sudden drop in sludge temperature, freezing or re-wetting, reducing drying efficiency. 4) Wastewater treatment challenges: The treatment costs of condensate and neutralized wastewater generated by the process are high and require a large area. In addition, traditional biochemical treatment processes are difficult to operate and maintain and have unstable treatment effects.

[0005] To address the aforementioned technical problems, this invention optimizes the design of the sludge biological drying process, develops a new type of dedicated sludge biological drying agent, and improves the structure of the biological drying chamber and its supporting systems. This results in a significant reduction in odor generation and a substantial increase in dewatering efficiency during the sludge biological drying process, while also taking into account the requirements of harmlessness, resource utilization, energy conservation, and environmental protection. This provides the sludge treatment industry with an efficient, stable, and environmentally friendly overall solution. Summary of the Invention

[0006] The purpose of this invention is to provide a process and biological drying chamber for the rapid treatment of odor-generating and dewatering sludge through biological drying, thereby solving the problems of severe odor generation, low dewatering efficiency, unstable operation, and difficult wastewater treatment in traditional sludge biological drying technology, and promoting the technological progress and industrial development of the sludge treatment industry.

[0007] To achieve the above technical solution, this invention discloses a biological drying chamber treatment process, comprising the following steps: S1: Mix organic sludge with agricultural and forestry waste in a certain proportion. Add sludge biological drying agent during the mixing process, adjust the carbon-nitrogen ratio of the material to 15-25, and the moisture content to 60%. Mix thoroughly and evenly to obtain a mixture. S2: Put the mixture into the biological drying chamber, turn on the aeration system, and raise the temperature of the mixture to 70-85℃ within 12-24 hours. Use sludge biological drying agent for biological deodorization and dewatering treatment. S3: After 10-16 days of biological drying, the sludge moisture content drops to 25%-30%, yielding a product that can be used as biomass fuel or nutrient soil.

[0008] Furthermore, the sludge biological drying agent is composed of Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis GDMCC No:63043, Bacillus filamentosa GDMCC No:63044, and a biocatalyst.

[0009] Furthermore, the biological deodorization includes: Odor control at the source: Strong ventilation and oxygen supply for 4-6 hours in the initial stage of biological drying to switch the warehouse to an aerobic environment; Drying for 12-24 hours to make the surface temperature of the material reach 70-85℃ to kill odor-producing bacteria; The odor-reducing bacteria in the sludge biological drying agent inhibit and kill heat-resistant facultative anaerobic odor-producing bacteria, achieving more than 80% odor reduction. The first-end purification and deodorization process uses downstream environmental protection equipment to purify residual odors and dust, hydrogen sulfide, and ammonia in the exhaust gas step by step, so as to achieve the standard emission of exhaust gas.

[0010] Furthermore, the specific steps of the end-of-pipe purification are as follows: dust is treated by water washing, hydrogen sulfide is converted into harmless substances such as amino acids and proteins by Ruisike third-generation sulfur fixation technology, ammonia is treated by acid washing and neutralization process, and the exhaust gas after the above treatment enters the biological deodorization box to degrade the residual malodorous substances and then meets the emission standards.

[0011] Furthermore, in the pickling and neutralization process, oxalic acid and citric acid are used as neutralizing agents under normal operating conditions, while sulfuric acid or hydrochloric acid is used as neutralizing agents under special operating conditions.

[0012] Furthermore, it also includes a sludge wastewater treatment step, wherein the wastewater is condensate and neutralization wastewater generated by the process, and the total amount is 1%-5% of the original sludge. The wastewater is returned to the sludge temporary storage area by a reflux treatment method, and then mixed with sludge, agricultural and forestry waste materials and dried again to achieve zero discharge.

[0013] The present invention also discloses a biological drying chamber, including a civil engineering part, a chamber body part, an aeration system, a sludge biological drying agent addition device and an exhaust gas treatment system; The civil engineering portion consists of three walls, with a wall height of 1-3 meters, a length of 5-100 meters, and a width of 5-20 meters. The silo body is installed on three walls of the civil engineering section and is equipped with a sealed silo, exhaust gas and odor control equipment, roller shutter door and water guide channel. The aeration system is embedded in the bottom of the chamber. The exhaust gas treatment system includes an axial flow fan and environmental protection equipment.

[0014] Furthermore, the height of the sealed silo body is 50cm above the lifting height of the forklift; insulation foam is added to the silo body in colder areas during winter; the water guide channel is set along the internal wall of the silo body to drain condensate; the roller shutter door is set at the reserved inlet and outlet of the civil engineering part for loading vehicles to quickly load and unload materials.

[0015] Furthermore, the aeration system supplies air at a rate of 4-10 times the volume of the entire chamber, and the aeration method involves multiple small fans supplying air individually, or one large fan supplying air through 2-10 pipes; the axial flow fan of the exhaust gas treatment system is installed at the front or rear of the top of the drying chamber, and the hourly exhaust flow rate of the axial flow fan is 10-20 times the volume of the chamber; the environmental protection treatment equipment includes a water washing tower, an acid washing tower, an alkali washing tower, a biological deodorization box, and a chimney.

[0016] Furthermore, the treated sludge completely kills roundworm eggs, has ≤100 E. coli / gram, is odorless, and has a calorific value of 2000-3500 kcal / kg; the energy consumption for treating each ton of mixed material is less than 55 kWh, and the weight of the mixed material is reduced by 50%-70%.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1) This invention features highly efficient deodorization and environmental friendliness: Through a dual deodorization strategy of "source control + end-of-pipe purification", the amount of odor generated during the biological drying of sludge is reduced by more than 80%, and the exhaust gas meets emission standards after multi-stage purification, completely solving the problem of serious odor generation in traditional technologies, significantly reducing the impact on the surrounding atmospheric environment, and reducing environmental disputes. 2) This invention has high dewatering efficiency and breaks through the technical limit: by utilizing the synergistic effect of medium and high temperature strong aerobic bacteria and biocatalyst, the sludge moisture content is reduced from 60% to 25%-30%, breaking through the bottleneck of traditional technology that is difficult to reduce the moisture content to below 40%, meeting the moisture content requirements of high value-added fields such as biomass fuel, and improving the resource utilization value of sludge. 3) This invention is thorough in harmlessness and safe and reliable: the treated sludge fully meets the epidemic prevention standards, all roundworm eggs are killed, the content of Escherichia coli is ≤100 / gram, and there is no odor. It completely eliminates pathogenic microorganisms and malodorous pollution in the sludge, and realizes the harmless treatment of sludge. 4) This invention has high resource value and turns waste into treasure: the calorific value of the treated sludge reaches 2000-3500 kcal / kg, which can be directly used as biomass fuel for heating and power generation, or as nutrient soil for landscaping and agricultural planting, realizing the high-value resource utilization of sludge, which is in line with the concept of circular economy development. 5) This invention has significant volume reduction and lower subsequent treatment costs: After processing by this process, the weight of the mixed materials is reduced by 50%-70%, the sludge volume is greatly reduced, and the transportation, storage and subsequent disposal costs of sludge are significantly reduced. 6) This invention is energy-saving and environmentally friendly with low operating costs: the energy consumption for processing each ton of mixed material is controlled within 55 kWh, which is far lower than that of traditional thermal drying technology, thus reducing operating costs and carbon emissions; at the same time, the wastewater recirculation treatment achieves zero discharge of process wastewater, with no external wastewater pollution, further improving the environmental friendliness of the process. 7) This invention features optimized structure and high drying efficiency: the closed chamber, aeration system, water guide channel, and exhaust gas treatment system of the biological drying chamber are designed in a coordinated manner, which reduces condensate backflow, ensures oxygen supply, and enables rapid discharge of waste gas, thereby greatly improving biological drying efficiency and shortening the drying cycle. 8) This invention features stable operation and simple maintenance: the aeration system can flexibly select the fan configuration, which is easy to replace after failure, and the chamber can be equipped with heat insulation foam to adapt to low temperature environment, so the process operation is less affected by environmental factors; no complicated manual operation is required throughout the process, and parameter adjustment can be achieved by real-time monitoring of the temperature and moisture content in the chamber, so the operation and maintenance difficulty is low. 9) This invention is highly adaptable and has a wide range of applications: it is suitable for the treatment of various organic sludges, including municipal sludge, kitchen waste, garden waste, agricultural and forestry waste, and industrial organic solid waste (wine lees, pharmaceutical lees, food factory sludge, etc.). The size of the biological drying chamber can be flexibly designed according to the actual treatment scale, and it is suitable for sludge treatment needs in different scenarios such as towns and industrial parks. Attached Figure Description

[0018] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention, primarily used to illustrate the embodiments and to explain the operating principles of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0019] Figure 1 This is a flowchart of the sludge biological drying process of the present invention; Figure 2 This is a flowchart of the sludge deodorization technology of the present invention; Figure 3 This is a schematic diagram of the structure of the biological drying chamber of the present invention; Figure 4 This is a schematic diagram of the civil engineering structure of the present invention; Figure 5 A schematic diagram of the device for adding biological drying agent to sludge.

[0020] Attached reference numerals: 1-Civil engineering part, 2-Storage body part, 3-Aeration system, 4-Sludge biological drying agent addition device, 5-Torrent odor control equipment, 6-Water guide channel, 7-Roller curtain. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1 To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Please see the appendix Figures 1 to 5As shown: A biological drying chamber treatment process uses raw material pretreatment, biological drying, and product treatment as its core steps. The entire process combines a specialized drying agent with optimized operating parameters to achieve simultaneous and efficient deodorization and dehydration. The specific steps are as follows: S1 Raw Material Pretreatment: The raw material organic sludge is mixed with the auxiliary material agricultural and forestry waste (such as straw and sawdust) in a certain proportion. During the mixing process, sludge biological drying agent is added evenly to adjust the carbon-nitrogen ratio of the material to 15-25 and the moisture content to about 60%. After thorough mixing, a mixture is obtained. The precise control of the carbon-nitrogen ratio and moisture content provides a suitable growth environment for the efficient metabolism of microorganisms. S2 biological drying: The mixture is put into the biological drying chamber, the inlet and outlet roller shutters are closed, and the aeration system is turned on. Through forced ventilation and oxygen supply, the mixture in the chamber is rapidly heated to 70-85℃ within 12-24 hours. The sludge biological drying agent containing medium- and high-temperature aerobic bacteria, deodorizing bacteria, and biological catalysts added to the mixture is used for biological deodorization and dewatering. This temperature range can ensure the efficient metabolism of medium- and high-temperature bacteria, and can also kill pathogens and odor-producing bacteria through high temperature. S3 Product Processing: After 10-16 days of continuous biological drying, the moisture content of the sludge in the silo is reduced to 25%-30%, directly yielding a finished product that can be used as biomass fuel or nutrient soil, without the need for additional subsequent processing.

[0024] Based on the above embodiments, the sludge biological drying agent is a compound special bacterial agent composed of Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, RISAK proprietary strain 1 (Bacillus licheniformis GDMCC No: 63043), Bacillus filamentosa GDMCC No: 63044, and a biocatalyst. Among them, the medium- and high-temperature strong aerobic bacterial group (Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, etc.) efficiently degrades organic matter to generate biological heat, realizing sludge heating and dewatering; the deodorizing bacterial group inhibits and kills odor-producing bacteria, reducing odor generation from the source; the biocatalyst reduces the sensitivity of microorganisms to moisture, increases the material exchange capacity of microorganisms, breaks through the moisture limit of sludge drying, and improves dewatering efficiency.

[0025] Based on the above embodiments, sludge deodorization adopts a two-pronged deodorization strategy of "source control + end-of-pipe purification," achieving a reduction of over 80% in odor generation and ensuring that all exhaust gas emissions meet standards throughout the process. Specifically: 1) Source control: Odor reduction is achieved at the source through a three-step coordinated approach, with an odor reduction efficiency of over 80%. In the initial stage of biological drying, strong ventilation and oxygen supply are carried out for 4-6 hours to quickly switch the environment inside the chamber from anaerobic to aerobic, kill most of the anaerobic odor-producing bacteria, and reduce anaerobic odor production from the source. Drying for 12-24 hours raises the surface temperature of the material to 70-85℃, killing heat-resistant odor-producing bacteria through high temperature, and further reducing odor production. The enzymes and hormones produced by the deodorizing bacteria in the special sludge biological drying agent inhibit and kill the reproduction of thermophilic facultative odor-producing bacteria, and continuously prevent odor generation.

[0026] 2) End-of-pipe purification: For the small amount of residual odor generated during the sludge unloading stage and the initial drying stage, as well as dust, hydrogen sulfide, and ammonia in the exhaust gas, staged purification is carried out through downstream environmental protection equipment to ensure that the final emissions meet standards. Dust treatment: A water washing process is used to transfer dust in the exhaust gas into water, achieving efficient dust removal. The wastewater is then collected and treated in a unified manner. Hydrogen sulfide treatment: Using Ruisike's third-generation sulfur fixation technology, hydrogen sulfide in the waste gas is converted into harmless organic substances such as amino acids and proteins, achieving near-zero emissions of hydrogen sulfide. Ammonia treatment: An acid washing and neutralization process is adopted. Under normal operating conditions, oxalic acid and citric acid are selected as neutralizing agents. Under special high-concentration operating conditions, sulfuric acid or hydrochloric acid is used instead. Ammonia reacts with the acid to generate ammonium salts. The neutralized products are collected and treated together with the wastewater. Residual odor treatment: The exhaust gas after the above treatment enters the biological deodorization box, where residual volatile organic odorous substances are degraded by the metabolic action of biological deodorizing bacteria, and the exhaust gas that finally meets the standards is discharged into the air through the chimney.

[0027] Based on the above embodiments, sludge wastewater treatment mainly includes condensate from the silo and neutralized wastewater from the exhaust gas treatment process. The total amount of wastewater is only 1%-5% of the original sludge, with a higher proportion of condensate in winter due to low temperatures. This invention provides two wastewater treatment methods, with wastewater recirculation treatment being preferred to achieve zero discharge, specifically: 1) Biological treatment pond: Construct a biological treatment pond, and pass the collected wastewater into the biological treatment pond. The pollutants in the wastewater are degraded by microbial metabolism and discharged after treatment to meet the standards. The disadvantages of this method are large initial investment, large area, difficult operation and maintenance, and the treatment effect is easily affected by environmental factors and is unstable. 2) Wastewater recirculation treatment: The collected condensate and neutralized wastewater are recirculated to the sludge storage area, mixed with the sludge to be treated and agricultural and forestry waste materials, and then subjected to secondary drying treatment in the biological drying process. This method only increases the aeration energy consumption by a small amount, and can achieve zero discharge of process wastewater and no external wastewater discharge, which greatly reduces environmental risks and wastewater treatment costs, making it the preferred treatment method.

[0028] Furthermore, this invention also discloses a biological drying chamber as an integrated specialized device, comprising a civil engineering component 1, a chamber body 2, an aeration system 3, a sludge biological drying agent addition device 4, and an exhaust gas treatment system 5. The structural design and function of each component are matched to maximize biological drying efficiency. The specific structure is as follows: The civil engineering section 1 is a three-wall structure with a wall height of 1-3 meters, a length of 5-100 meters, and a width of 5-20 meters. Of course, it can be flexibly designed according to the actual processing scale. It is mainly used to accommodate sludge mixture and provide basic bearing space for the drying process. Section 2 consists of three sealed chambers installed on the three walls of the civil engineering section. The height of the sealed chambers is 50cm above the lifting height of the forklift, facilitating the operation of forklifts and other equipment. The core function of the sealed chambers is to collect the large amount of water vapor generated during the biological drying process, reducing the backflow of moisture to the material surface. The chambers are equipped with exhaust gas and odor control devices to promptly discharge hot and waste gases into the subsequent exhaust gas treatment system. One side is reserved as an inlet and outlet, with a roller shutter door installed to enable rapid loading and unloading of loader vehicles, improving loading and unloading efficiency. For colder regions in winter, insulation foam can be added to the outside of the chambers to reduce heat loss and condensation, increasing the drying production speed. Water guide channels are installed along the walls inside the chambers to quickly drain condensation generated on the chamber walls, accelerating the sludge biological drying process. The aeration system 3 is pre-embedded at the bottom of the biological drying chamber, providing sufficient oxygen for microbial metabolism. Its air supply is 4-10 times the volume of the entire chamber. There are two aeration methods: one is multiple small blowers supplying air individually, which is efficient, energy-saving, and easy to replace after blower failure without affecting the overall operation; the other is one large blower with 2-10 pipes supplying air, which is suitable for small-scale treatment scenarios. The sludge biological drying agent addition device 4 is installed at the inlet of the biological drying chamber to achieve uniform mixing and addition of the drying agent with sludge and auxiliary materials, and to ensure the dispersibility of the drying agent in the mixture. The exhaust gas treatment system 4 consists of an axial flow fan and environmental protection equipment. The axial flow fan is installed at the front or rear of the top of the drying chamber. Its effective exhaust flow rate is designed according to the volume of the chamber. The hourly exhaust flow rate needs to reach 10 to 20 times the volume of the chamber to ensure that the exhaust gas in the chamber is discharged quickly. The exhaust gas discharged by the axial flow fan is collected through a sealed pipeline to the environmental protection equipment for centralized treatment. The environmental protection equipment includes a water washing tower, an acid washing tower, an alkali washing tower, a biological deodorization box, and a chimney, which realizes the step-by-step purification of dust, hydrogen sulfide, ammonia, and residual odor in the exhaust gas.

[0029] Example 2 Please see the appendix Figures 1 to 3 As shown: This embodiment uses municipal sewage sludge as the treatment raw material. The invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Municipal sludge was selected as the raw material for treatment, and straw and sawdust were used as auxiliary materials from agricultural and forestry waste. The municipal sludge was mixed with straw and sawdust in a certain proportion, and the carbon-nitrogen ratio of the materials was adjusted to 20 and the moisture content to 60%. During the mixing process, a sludge biological drying agent (composed of Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis GDMCC No:63043, Bacillus filamentosa GDMCC No:63044 and a biocatalyst) was added evenly through a drying agent adding device. After thorough stirring and mixing, a mixture was obtained.

[0031] A forklift is used to feed the mixture into the biological drying chamber through a roller shutter door. After feeding, the roller shutter door is closed. The biological drying chamber has three walls, each 2 meters high, 20 meters long, and 10 meters wide. Insulation foam is installed in the chamber (in this example, the insulation foam is for a normal temperature area and is a backup). The aeration system is activated, using multiple small fans to supply air individually, with the air supply volume set to 5 times the chamber volume. Through forced ventilation and oxygen supply, the mixture inside the chamber rapidly heats up to 75°C within 12 hours. Simultaneously... The exhaust gas treatment system is activated, and the exhaust flow rate of the axial flow fan is set to 15 times the volume of the silo per hour to quickly collect the hot and waste gas inside the silo to the environmental protection equipment. During the biological drying process, the temperature, moisture content, and odor concentration of the mixture inside the silo are monitored in real time. The aeration rate and the amount of drying agent added are finely adjusted according to the monitoring results to ensure that the temperature inside the silo is stable at 70-85℃. After 12 days of continuous biological drying treatment, the aeration and exhaust gas treatment systems are stopped, the roller shutter door is opened, and the material inside the silo is removed by a forklift.

[0032] Source control: In the first 5 hours after the start of biological drying, the aeration system is turned on to provide strong ventilation and oxygen supply, and an aerobic environment is quickly achieved in the chamber; after 12 hours of drying, the surface temperature of the material is monitored to be stable at 72℃, and the odor-producing bacteria are killed by high temperature; at the same time, the deodorizing bacteria in the sludge biological drying agent are used to continuously inhibit the reproduction of thermophilic facultative odor-producing bacteria. End-of-pipe purification: During the initial drying stage and the sludge unloading stage, the exhaust gas treatment system is kept running continuously. The exhaust gas first enters the water washing tower to remove dust through the water washing process; then it enters the acid washing tower, where citric acid is used as a neutralizing agent to remove ammonia; then it enters the dedicated treatment unit, where hydrogen sulfide is converted into harmless organic substances through the RISAK third-generation sulfur fixation technology; finally, it enters the biological deodorization box to degrade residual malodorous substances, and the qualified exhaust gas is discharged into the atmosphere through the chimney. The concentrations of dust, hydrogen sulfide, ammonia, and odor in the exhaust gas are monitored in real time throughout the process to ensure that all indicators meet the national environmental protection standards of the "Odor Pollutant Emission Standard" (GB14554-93) and the "Integrated Emission Standard of Air Pollutants" (GB16297-1996).

[0033] The condensate collected in the water guide tank during the biological drying process, as well as the neutralized wastewater generated by the water washing tower and acid washing tower during the tail gas treatment process, are collected together in the wastewater pool. The wastewater is then pumped back to the municipal sludge temporary storage area, where it is mixed with the municipal sludge to be treated and straw auxiliary materials, and then enters the raw material pretreatment step for secondary drying treatment to achieve zero discharge of process wastewater.

[0034] A comprehensive test was conducted on the finished sludge product, process energy consumption, and exhaust gas emissions after treatment in this embodiment. The test results are shown in the table below:

[0035] Specifically, regarding process energy consumption: the energy consumption per ton of mixed material is 52 kWh, lower than the design target of 55 kWh, resulting in low operating costs; regarding exhaust gas emissions: the concentrations of dust, hydrogen sulfide, and ammonia in the exhaust gas all meet national environmental protection standards, and the odor concentration is reduced by 85% compared to traditional processes, achieving compliant emissions; regarding volume reduction: the mixed material is reduced in weight by 65% ​​after treatment, and the sludge volume is significantly reduced, demonstrating a significant volume reduction effect; regarding finished sludge indicators: the moisture content is 28%, all roundworm eggs are killed, the E. coli content is ≤100 CFU / g, there is no obvious odor, and the calorific value is 2800 kcal / kg, making it suitable for direct use as biomass fuel. Therefore, the process and biological drying chamber of this invention can efficiently and environmentally treat municipal sludge, achieving the harmlessness, volume reduction, and resource utilization of sludge. All indicators meet the design requirements, demonstrating significant economic, environmental, and social benefits.

[0036] In summary, this invention employs a dual deodorization strategy of "source control + end-of-pipe purification," combining specialized microbial agents and biocatalysts to reduce odor production during sludge biological drying by over 80%, achieving odor emission standards and minimizing negative impacts on the surrounding environment. Utilizing the synergistic effect of high-temperature aerobic bacteria and biocatalysts, it overcomes the drying moisture limits of traditional technologies, reducing sludge moisture content from 60% to 25%-30%, meeting the moisture content requirements for high-value applications such as biomass fuel. The treated sludge meets epidemic prevention standards, completely eliminating roundworm eggs and E. coli. With a bacterial content ≤100 CFU / g and no odor, the environmental and health risks of sludge are eliminated; the calorific value of the treated sludge reaches 2000-3500 kcal / kg, which can be directly used as biomass fuel or nutrient soil for resource utilization, realizing the high-value transformation of sludge; the energy consumption per ton of mixed material is controlled within 55 kWh, reducing operating costs and carbon emissions; at the same time, zero discharge of process wastewater is achieved, further reducing environmental pollution; it is suitable for the treatment of various organic solid wastes, and the process operation is less affected by environmental factors, simple to operate, and low in maintenance difficulty.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art should be able to make equivalent embodiments by making some changes or modifications to the above-disclosed technical content without departing from the scope of the present invention. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A biological drying chamber treatment process, characterized in that, Includes the following steps: S1: Mix organic sludge with agricultural and forestry waste in a certain proportion. Add sludge biological drying agent during the mixing process, adjust the carbon-nitrogen ratio of the material to 15-25, and the moisture content to 60%. Mix thoroughly and evenly to obtain a mixture. S2: Put the mixture into the biological drying chamber, turn on the aeration system, and raise the temperature of the mixture to 70-85℃ within 12-24 hours. Use sludge biological drying agent for biological deodorization and dewatering treatment. S3: After 10-16 days of biological drying, the sludge moisture content drops to 25%-30%, yielding a product that can be used as biomass fuel or nutrient soil.

2. The biological drying chamber treatment process as described in claim 1, characterized in that, The sludge biological drying agent is composed of Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis GDMCC No:63043, Bacillus filamentosa GDMCC No:63044 and a biocatalyst.

3. The biological drying chamber treatment process as described in claim 1, characterized in that, The biological deodorization includes: Odor control at the source: Strong ventilation and oxygen supply for 4-6 hours in the initial stage of biological drying to switch the warehouse to an aerobic environment; Drying for 12-24 hours to make the surface temperature of the material reach 70-85℃ to kill odor-producing bacteria; The odor-reducing bacteria in the sludge biological drying agent inhibit and kill heat-resistant facultative anaerobic odor-producing bacteria, achieving more than 80% odor reduction. End-of-pipe purification and deodorization involves using downstream environmental protection equipment to purify residual odors and dust, hydrogen sulfide, and ammonia in the exhaust gas step by step, achieving compliant emissions.

4. The biological drying chamber treatment process as described in claim 3, characterized in that, The specific steps of the end-of-pipe purification are as follows: dust is treated by water washing, hydrogen sulfide is converted into harmless substances such as amino acids and proteins by sulfur fixation technology, ammonia is treated by acid washing and neutralization process, and the exhaust gas after the above treatment enters the biological deodorization box to degrade the residual malodorous substances and then meets the emission standards.

5. The biological drying chamber treatment process as described in claim 4, characterized in that, In the pickling neutralization process, oxalic acid and citric acid are used as neutralizing agents under normal conditions, while sulfuric acid or hydrochloric acid is used as neutralizing agents under special conditions.

6. The biological drying chamber treatment process as described in claim 1, characterized in that, It also includes a sludge wastewater treatment step, wherein the wastewater is the condensate and neutralization wastewater generated by the process, and the total amount is 1%-5% of the original sludge. The wastewater is returned to the sludge temporary storage area by a reflux treatment method, and then mixed with sludge, agricultural and forestry waste materials and dried again to achieve zero discharge.

7. A bio-drying chamber for implementing the process according to any one of claims 1-6, characterized in that, Includes civil engineering components, storage tank components, aeration system, sludge biological drying agent addition device, and exhaust gas treatment system; The civil engineering portion consists of three walls, with a wall height of 1-3 meters, a length of 5-100 meters, and a width of 5-20 meters. The silo body is installed on three walls of the civil engineering section and is equipped with a sealed silo, exhaust gas and odor control equipment, roller shutter door and water guide channel. The aeration system is pre-embedded at the bottom of the chamber, and the air supply of the aeration system is 4-10 times the volume of the chamber. The exhaust gas treatment system includes an axial flow fan and environmental protection equipment.

8. The biological drying chamber as described in claim 7, characterized in that, The height of the sealed silo body is 50cm above the lifting height of the forklift; the silo body in colder winter areas is equipped with thermal insulation foam; the water guide channel is set along the internal wall of the silo body to drain condensate; the roller shutter door is set at the reserved inlet and outlet of the civil engineering part for loading vehicles to quickly load and unload materials.

9. The biological drying chamber as described in claim 7, characterized in that, The aeration system supplies air at a rate of 4-10 times the volume of the entire chamber. The aeration method involves multiple small fans supplying air individually, or a large fan supplying air through 2-10 pipes. The axial flow fan of the exhaust gas treatment system is installed at the front or rear of the top of the drying chamber, and the hourly exhaust flow rate of the axial flow fan is 10-20 times the volume of the chamber. The environmental protection treatment equipment includes a water washing tower, an acid washing tower, an alkali washing tower, a biological deodorization box, and a chimney.

10. The bio-drying chamber treatment process according to any one of claims 1-6 or the bio-drying chamber according to any one of claims 7-9, characterized in that, The treated sludge is completely free of roundworm eggs, with E. coli counts ≤100 per gram, odorless, and has a calorific value of 2000-3500 kcal / kg. The energy consumption for each ton of mixed material is less than 55 kWh, and the weight of the mixed material is reduced by 50%-70%.

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