A system and method for synergistic treatment of three wastes in a fermentation residue treatment process

Abstract

The application discloses a kind of three wastes in fermentation microbial residue treatment process and method for treating system and method, including fermentation microbial residue, microbial residue sterilization tank, waste gas outlet, second fan, delivery pump, RTO heat accumulation incineration device, first fan, primary dehydration subsystem, secondary dehydration subunit, tertiary dehydration subunit, pyrolysis unit, pyrolysis gas, pyrolysis carbon, activated carbon, high-temperature furnace gas, third fan, liquid discharge pipeline, exhaust pipe, waste water treatment subsystem, marsh gas, circulating water pump, spray tower, gas-liquid separator, fire arrester, oxidation fan, exhaust pipe, fermentation microbial residue is first into microbial residue sterilization tank and is sterilized, and fermentation microbial residue is from the top of microbial residue sterilization tank into microbial residue sterilization tank, and mechanical stirring device is arranged in microbial residue sterilization tank, to ensure that fermentation microbial residue is uniformly heated, and there is waste gas outlet in the top of microbial residue sterilization tank, and it is connected with second fan, can realize the negative pressure operation of microbial residue sterilization tank, ensure that waste gas is not leaked, and ensure that inactivated strain is not leaked.

Description

Technical Field

[0001] This invention relates to a method for treating fermentation residue, specifically a system and method for the synergistic treatment of three wastes during the fermentation residue treatment process. Background Technology

[0002] Fermentation is a biotechnology that utilizes the metabolic products of microorganisms. It is widely used in the production of pharmaceutical products such as antibiotics, enzymes, and biological agents, and is an indispensable stage in the production of most traditional Chinese medicines and Western medicines. Because fermentation residue inevitably contains a large number of microbial communities, especially in the production of antibiotics, it may contain small amounts of toxic and harmful residues, posing a potential threat to the ecological environment. In my country, it is listed in the "National Hazardous Waste List" under waste category HW02.

[0003] Currently, the main methods for treating fermentation residue include incineration, pyrolysis, composting, and anaerobic digestion. However, these technologies still have certain limitations. Incineration and pyrolysis can achieve the harmless treatment of fermentation residue; however, because the moisture content of fermentation residue is usually high (approximately 85%-90%), incineration and pyrolysis result in high energy consumption, incomplete treatment, and the potential generation of secondary pollutants. While composting and anaerobic digestion can both achieve sufficient degradation of organic matter in the residue, the degradation time is typically long, leading to low treatment efficiency. Furthermore, the presence of toxic and harmful residues can inhibit the degradation rate of fermentation residue, making it difficult for composting and anaerobic digestion technologies to achieve complete harmless treatment.

[0004] Therefore, regardless of the treatment method used, efficient and stable operation hinges on sterilization and addressing the high moisture content of the fermentation residue. Researchers have therefore disclosed different treatment approaches. For instance, physical treatment methods such as high temperature and pressure, and high-energy electron beams are highly effective in disrupting the antibiotic structure. These methods effectively eliminate microbial communities in the fermentation residue, significantly reducing the material's moisture content. However, they involve large equipment investments and high operating costs, hindering large-scale promotion and application. Another approach involves chemical methods such as using strong acids, strong alkalis, or strong oxidants to treat the residue. While these methods can disrupt the antibiotic structure, the harsh chemical environment severely impacts subsequent processing equipment, greatly increasing the difficulty of later stages. Thus, reducing operating costs and addressing energy consumption remain key challenges.

[0005] Furthermore, the fermentation residue inevitably generates waste liquid and waste gas during the processing. The treatment of these secondary pollutants is a pressing issue. Currently, publicly available solutions focus on the harmless or resource-based treatment of the fermentation residue; however, there are no publicly reported solutions addressing the treatment of the waste gas, waste liquid, and waste residue itself generated during the process. Finding a suitable solution for treating these three wastes without increasing energy consumption is currently of paramount importance. Summary of the Invention

[0006] The purpose of this invention is to provide a system and method for the synergistic treatment of three wastes during the treatment of fermentation residue, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A system and method for the coordinated treatment of three wastes during the treatment of fermentation residue includes fermentation residue, a residue sterilization tank, a waste gas outlet, a second blower, a transfer pump, an RTO regenerative thermal oxidizer, a first blower, a primary dehydration subsystem, a secondary dehydration subunit, a tertiary dehydration subunit, a pyrolysis unit, pyrolysis gas, pyrolysis char, activated carbon, high-temperature furnace gas, a third blower, a liquid discharge pipe, an exhaust pipe, a wastewater treatment subsystem, biogas, a circulating water pump, a spray tower, a gas-liquid separator, a flame arrester, an oxidation blower, and an exhaust stack. The system is characterized in that the fermentation residue first enters the residue sterilization tank for sterilization treatment, and the fermentation residue enters the sterilization tank from the top. The sterilization tank is equipped with a mechanical stirring device. The top of the sterilization tank has an exhaust gas outlet connected to a second blower, enabling negative pressure operation. The bottom of the sterilization tank is connected to a transfer pump, which promptly delivers the sterilized solids and liquids to the subsequent dehydration system. The sterilization method is high-temperature sterilization, using high-temperature flue gas sourced from the exhaust gas from the RTO regenerative thermal oxidizer in the waste gas integrated treatment subsystem. This exhaust gas is discharged into the atmosphere through an exhaust stack. Powered by the first blower, the high-temperature flue gas enters the sterilization tank through three inlets: the top, middle, and bottom. The flue gas flow rate is regulated by pipeline valves.

[0009] As a further aspect of the present invention: after sterilization, the solid and liquid are promptly sent to the subsequent dehydration system. They first enter the primary dehydration subsystem for dehydration treatment. The primary dehydration subsystem uses mechanical dehydration, and the device used is a horizontal centrifuge. The device used for cell wall breaking treatment is a microwave oscillator. After cell wall breaking treatment and mechanical dehydration treatment, the solid and liquid are processed.

[0010] As a further aspect of the present invention: After primary dehydration, the material enters the secondary dehydration subunit, which employs low-temperature dehydration using a low-temperature heat pump belt dehydrator. The heat source for low-temperature dehydration also originates from the exhaust gas from the RTO regenerative thermal oxidizer, and the material is transported under the power of the first blower. After secondary dehydration, the material enters the tertiary dehydration subunit, which employs high-temperature dehydration using a partitioned paddle high-temperature dryer. The heat source for high-temperature dehydration originates from the high-temperature flue gas used in the pyrolysis unit. After tertiary dehydration, the material enters the pyrolysis unit for resource utilization. The pyrolysis unit uses a chain plate pyrolysis furnace. After dehydration, the solid bacterial residue is pyrolyzed to form pyrolysis gas and pyrolysis char. The pyrolysis gas is directly fed into the RTO regenerative thermal oxidizer to provide fuel, and the pyrolysis char can be further used to prepare biomass-based activated carbon.

[0011] As a further aspect of the present invention: the heat required by the pyrolysis furnace mainly comes from the high-temperature furnace gas generated in the furnace of the RTO regenerative thermal oxidizer in the waste gas integrated treatment system. Under the power transmission of the third fan, the high-temperature furnace gas first provides a heat source for the pyrolysis unit, and then further enters the three-stage dehydration sub-unit.

[0012] As a further aspect of the present invention: the first, second, and third stage dehydration subsystems are each equipped with a drain pipe and an exhaust pipe, which are then combined to form a mixed waste liquid and a mixed waste gas. The mixed waste liquid formed by the dehydration subsystem first enters the wastewater treatment subsystem, which adopts a combination of pretreatment and biochemical treatment. The biochemical treatment process can also produce biogas, which can be used as the main fuel for the RTO regenerative thermal oxidizer. The effluent formed by the wastewater treatment subsystem is directly pumped into the spray tower by a circulating water pump to be used as spray cooling water. At the same time, the wastewater generated by the spray tower can enter the wastewater treatment subsystem for treatment.

[0013] As a further aspect of the present invention: the mixed waste gas generated during the dehydration process of the dehydration system is pretreated by a spray tower and a gas-liquid separator in sequence, and then enters the waste gas integrated treatment subsystem under the conveying of a third fan. The waste gas integrated treatment subsystem mainly includes a flame arrester, an oxidation fan and an RTO waste gas incineration device connected in sequence. The system mainly treats waste gas including vacuum waste gas from the bacterial residue sterilization tank, mixed waste gas generated by the dehydration system, pyrolysis gas generated during bacterial residue pyrolysis and biogas generated during wastewater treatment as fuel for the RTO regenerative thermal oxidizer in the waste gas integrated treatment subsystem.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] This invention discloses a system and method for the coordinated treatment of three wastes during the fermentation residue processing. The system mainly includes a sterilization subsystem, a dehydration subsystem, a pyrolysis subsystem, a water circulation treatment subsystem, and a comprehensive waste gas treatment subsystem. This system has the following beneficial effects:

[0016] 1. The system boasts strong integrity, with each subsystem capable of collaborative operation. This system focuses on the fermentation residue formed during the fermentation process, and develops a complete treatment process for the waste gas, waste liquid, waste residue, and different types of microorganisms generated during its harmless and resource-based treatment. This process involves multiple subsystems, including sterilization, cell wall disruption, dehydration, pyrolysis, water treatment, and waste gas treatment. These subsystems are interconnected and can work collaboratively.

[0017] 2. The process is stable, reliable, and highly operable. Addressing the difficulty in dewatering fermentation residue, this invention discloses a tiered dewatering process that combines dewatering with cell wall disruption, employing mechanical dewatering, low-temperature dewatering, and high-temperature dewatering methods to achieve tiered dewatering of the fermentation residue with higher efficiency.

[0018] 3. The system achieves cascaded utilization of high-temperature energy and waste heat recovery and reuse, resulting in high energy efficiency. Although the system involves processes such as high-temperature sterilization and high-temperature dehydration, its heat source originates from the RTO regenerative thermal oxidizer in the waste gas integrated treatment subsystem. The high-temperature furnace gas of the RTO serves as the main heat source for the pyrolysis unit and then enters the high-temperature dehydration subsystem for waste heat recovery and reuse. Furthermore, through optimized design of the heat storage medium in the RTO regenerative thermal oxidizer, its exhaust temperature meets the requirements of the high-temperature flue gas used in the bacterial residue sterilization tank and the secondary dehydration unit, eliminating the need for external heat sources and ensuring high system energy efficiency.

[0019] 4. The system requires no external fuel, resulting in low operating costs. The heat source for the entire treatment system comes from the RTO regenerative thermal oxidizer in the waste gas integrated treatment subsystem. The fuel for this oxidizer comes from the pyrolysis gas generated during the pyrolysis of dehydrated solid bacterial residue in the pyrolysis subsystem, and from the biogas generated during the biochemical treatment process of the wastewater treatment unit in the water circulation treatment subsystem. No other external fuel is required, which greatly reduces the system's operating costs. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a system and method for the coordinated treatment of three wastes during the fermentation residue treatment process. 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] Please see Figure 1 In this embodiment of the invention, a system and method for the coordinated treatment of three wastes during the treatment of fermentation residue includes fermentation residue 1, residue sterilization tank 2, waste gas outlet 3, second fan 4, conveying pump 5, RTO regenerative thermal oxidizer 6, first fan 7, primary dehydration subsystem 8, secondary dehydration subunit 9, tertiary dehydration subunit 10, pyrolysis unit 11, pyrolysis gas 24, pyrolysis char 13, activated carbon 14, high-temperature furnace gas 12, third fan 15, drain pipe 16, exhaust pipe 17, wastewater treatment subsystem 18, biogas 27, circulating water pump 19, spray tower 20, gas-liquid separator 21, flame arrester 22, oxidation fan 23, and exhaust stack 26.

[0023] The fermentation residue 1 first enters the residue sterilization tank 2 for sterilization. The residue 1 enters the sterilization tank 2 from the top. The sterilization tank 2 is equipped with a mechanical stirring device to ensure uniform heating of the fermentation residue 1. The top of the sterilization tank 2 has an exhaust gas outlet 3, connected to a second blower 4, which enables negative pressure operation of the sterilization tank 2, ensuring no exhaust gas leakage and preventing any unsterilized bacterial strains from escaping. The bottom of the sterilization tank 2 is connected to a conveying pump 5, which promptly delivers the sterilized solids and liquids to the subsequent dehydration system. The sterilization method is high-temperature sterilization. The high-temperature flue gas used comes from the exhaust gas of the RTO regenerative thermal oxidizer 6 in the waste gas integrated treatment subsystem. The exhaust gas can be discharged to the atmosphere through the exhaust stack 26. The exhaust temperature is about 200-250℃. Under the power of the first fan 7, the high-temperature flue gas enters the interior of the mushroom residue sterilization tank 2 from the upper, middle and lower air inlets respectively, so as to realize the segmented entry of high-temperature flue gas, thereby achieving uniform heating and sterilization of the mushroom residue sterilization tank 2. The flue gas flow rate is regulated by the pipeline valve.

[0024] After sterilization, the solids and liquids are promptly fed into the subsequent dehydration system. The mixture, with a moisture content of 85%-90%, first enters the primary dehydration subsystem 8 for mechanical dehydration using a horizontal centrifuge. To ensure the dehydration efficiency of the primary dehydration subsystem 8, the material undergoes a cell-wall breaking process before entering the centrifuge, using a microwave oscillator. After cell-wall breaking and mechanical dehydration, the moisture content of the material is reduced to 60%-65%.

[0025] After primary dehydration, the material enters secondary dehydration subunit 9, which employs low-temperature dehydration using a low-temperature heat pump belt dehydrator. The heat source for this low-temperature dehydration also comes from the exhaust gas from the RTO regenerative thermal oxidizer 6, with an exhaust temperature of approximately 200-250℃. The exhaust gas is conveyed under the power of the primary fan 7. After secondary dehydration, the moisture content of the material is reduced to 40-45%. Following secondary dehydration, the material enters tertiary dehydration subunit 10, which employs high-temperature dehydration. The equipment used is a partition-type paddle high-temperature dryer. The heat source for high-temperature dehydration comes from the high-temperature flue gas used in the pyrolysis unit 11. The temperature of this high-temperature flue gas after passing through the pyrolysis unit is approximately 550℃-600℃, thus realizing the reuse of the waste heat of the high-temperature flue gas. After three-stage dehydration, the moisture content of the material is reduced to 20-25%. After three-stage dehydration, the material enters the pyrolysis unit 11 for resource utilization. The equipment used in the pyrolysis unit 11 is a chain plate pyrolysis furnace to minimize the dust content in the pyrolysis gas. After dehydration, the solid bacterial residue is pyrolyzed to form pyrolysis gas 24 and pyrolysis char 13. Pyrolysis gas 24 is directly fed into the RTO regenerative thermal oxidizer 6 to provide fuel for the RTO regenerative thermal oxidizer 6. Pyrolysis char 13 can be further used to prepare biomass-based activated carbon 14, thereby realizing resource utilization.

[0026] The heat required by the pyrolysis furnace mainly comes from the high-temperature furnace gas 12 generated in the furnace of the RTO regenerative thermal oxidizer 6 in the waste gas integrated treatment system. The temperature of the high-temperature furnace gas 12 is approximately 800℃-850℃. Under the power transmission of the third fan 15, the high-temperature furnace gas 12 first provides a heat source for the pyrolysis unit 11, and the temperature drops slightly to 550℃-600℃. Then, it is further introduced into the three-stage dehydration sub-unit 10 to provide heat, thereby realizing the recovery and reuse of waste heat.

[0027] Each of the primary, secondary, and tertiary dewatering subsystems is equipped with a drain pipe 16 and an exhaust pipe 17, which, when combined, form a mixed waste liquid and a mixed waste gas. The mixed waste liquid from the dewatering subsystem first enters the wastewater treatment subsystem 18, where a combination of pretreatment and biochemical treatment is employed. Given the characteristics of this type of wastewater, the biochemical treatment method not only boasts high efficiency and good treatment effect but also generates biogas 27 and other combustible gases during the process. These combustible gases can be used as the main fuel for the RTO regenerative thermal oxidizer 6. The effluent from the wastewater treatment subsystem 18 is directly pumped into the spray tower 20 via the circulating water pump 19 for use as spray cooling water, thus achieving wastewater reuse. Simultaneously, the wastewater generated by the spray tower 20 can enter the wastewater treatment subsystem 18 for treatment, thereby achieving water resource recycling.

[0028] The mixed waste gas generated during the dehydration process of the dehydration system is pretreated by the spray tower 20 and the gas-liquid separator 21 in sequence, and then enters the waste gas integrated treatment subsystem under the conveying of the third fan 15. The waste gas integrated treatment subsystem mainly includes the flame arrester 22, the oxidation fan 23 and the RTO waste gas incineration device 6 connected in sequence. The system mainly treats the waste gas including the vacuum waste gas of the bacterial residue sterilization tank 2, the mixed waste gas generated by the dehydration system, the pyrolysis gas generated during the bacterial residue pyrolysis process and the biogas 27 generated during the wastewater treatment process, which are used as fuel for the RTO regenerative thermal ignition device 6 in the waste gas integrated treatment subsystem.

[0029] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A system for the coordinated treatment of three wastes during the treatment of fermentation residue, comprising fermentation residue (1), residue sterilization tank (2), waste gas outlet (3), second blower (4), transfer pump (5), RTO regenerative thermal oxidizer (6), first blower (7), primary dehydration subsystem (8), secondary dehydration subunit (9), tertiary dehydration subunit (10), pyrolysis unit (11), pyrolysis gas (24), pyrolysis char (13), activated carbon (14), high-temperature furnace gas (12), third blower (15), drain pipe (16), exhaust pipe (17), wastewater treatment subsystem (18), biogas (27), circulating water pump (19), spray tower (20), gas-liquid separator (21), flame arrester (22), oxidation blower (23), and exhaust stack (26), characterized in that, The fermentation residue (1) first enters the residue sterilization tank (2) for sterilization. The fermentation residue (1) enters the residue sterilization tank (2) from the top. The residue sterilization tank (2) is equipped with a mechanical stirring device. The residue sterilization tank (2) has a waste gas outlet (3) at the top, which is connected to the second blower (4) to realize the negative pressure operation of the residue sterilization tank (2). The bottom of the residue sterilization tank (2) is connected to the conveying pump (5) to send the sterilized solid and liquid into the subsequent dehydration system in a timely manner. The sterilization method is high temperature sterilization. The high temperature flue gas used comes from the exhaust of the RTO regenerative thermal incineration device (6) in the waste gas integrated treatment subsystem. The waste gas can be discharged to the atmosphere through the exhaust pipe (26). Under the power transmission of the first blower (7), the high temperature flue gas enters the residue sterilization tank (2) from the upper, middle and lower air inlets respectively. The flue gas flow rate is adjusted by the pipeline valve. After sterilization, the solid and liquid materials are promptly sent to the subsequent dehydration system. First, they enter the primary dehydration subsystem (8) for dehydration treatment. After primary dehydration, the materials enter the secondary dehydration subunit (9). After secondary dehydration, the materials enter the tertiary dehydration subunit (10). After tertiary dehydration, the materials enter the pyrolysis unit (11) for resource utilization. The equipment used in the pyrolysis unit (11) is a chain plate pyrolysis furnace. After dehydration, the solid bacterial residue can be pyrolyzed to form pyrolysis gas (24) and pyrolysis carbon (13). The pyrolysis carbon (13) can be further used to prepare biomass-based activated carbon (14). The heat required by the pyrolysis furnace mainly comes from the high-temperature furnace gas (12) generated in the furnace of the RTO regenerative thermal ignition device (6) in the waste gas integrated treatment system. Under the power transmission of the third fan (15), the high-temperature furnace gas (12) provides a heat source for the pyrolysis unit (11). The second and third dewatering subsystems are each equipped with a drain pipe (16) and an exhaust pipe (17), which are combined to form mixed waste liquid and mixed waste gas. The mixed waste liquid formed by the dewatering subsystem enters the wastewater treatment subsystem (18), which adopts a combination of pretreatment and biochemical treatment. Biogas can also be generated during the biochemical treatment process (27). The mixed waste gas generated during the dehydration process of the dehydration system is pretreated by the spray tower (20) and the gas-liquid separator (21) in sequence, and then enters the waste gas integrated treatment subsystem under the conveying of the third fan (15). The waste gas integrated treatment subsystem mainly includes the flame arrester (22), the oxidation fan (23) and the RTO waste gas incineration device (6) connected in sequence.

2. A method for the synergistic treatment of three wastes during the treatment of fermentation residue, based on the synergistic treatment system for three wastes during the treatment of fermentation residue as described in claim 1, characterized in that, The primary dehydration subsystem (8) uses mechanical dehydration, and the device used is a horizontal centrifuge. The device used for cell wall breaking is a microwave oscillator. After cell wall breaking and mechanical dehydration, the system is further processed.

3. The method for synergistic treatment of three wastes during the fermentation residue treatment process according to claim 2, characterized in that, The secondary dehydration subunit (9) adopts low-temperature dehydration, and the equipment used is a low-temperature heat pump belt dehydrator. The heat source used for low-temperature dehydration also comes from the exhaust gas after the RTO regenerative thermal ignition device (6), and is transported under the power of the first fan (7). The tertiary dehydration subunit (10) adopts high-temperature dehydration, and the equipment used is a partitioned paddle high-temperature dryer. The heat source used for high-temperature dehydration comes from the high-temperature flue gas used in the pyrolysis device in the pyrolysis unit (11). The pyrolysis gas (24) is directly introduced into the RTO regenerative thermal ignition device (6) to provide fuel for the RTO regenerative thermal ignition device (6).

4. The method for synergistic treatment of three wastes during the fermentation residue treatment process according to claim 2, characterized in that, The high-temperature furnace gas (12) first provides a heat source for the pyrolysis unit (11), and then further enters the three-stage dehydration sub-unit (10).

5. The method for synergistic treatment of three wastes during the fermentation residue treatment process according to claim 2, characterized in that, Biogas (27) can be used as the main fuel for the RTO regenerative thermal ignition device (6). The effluent generated by the wastewater treatment subsystem (18) is directly sent to the spray tower (20) by the circulating water pump (19) for use as spray cooling water. At the same time, the wastewater generated by the spray tower (20) can be treated in the wastewater treatment subsystem (18).

6. The method for synergistic treatment of three wastes during the fermentation residue treatment process according to claim 2, characterized in that, The waste gas integrated treatment subsystem mainly treats waste gas including vacuum waste gas from the bacterial residue sterilization tank (2), mixed waste gas generated by the dehydration system, pyrolysis gas generated during bacterial residue pyrolysis, and biogas (27) generated during wastewater treatment, which are used as fuel for the RTO regenerative thermal ignition device (6) in the waste gas integrated treatment subsystem.

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