Method for cooperatively treating antibiotic mushroom dregs based on hydrothermal-pyrolysis and advanced oxidation
By using a hydrothermal-pyrolysis and advanced oxidation co-processing method, the problems of incomplete treatment of antibiotic bacterial residue and single resource utilization pathways have been solved. This method achieves efficient resource recovery and harmless transformation, reduces energy consumption and costs, and forms an efficient internal material cycle.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SOUTH CHINA UNIV OF TECH
- Filing Date
- 2026-04-13
- Publication Date
- 2026-05-15
AI Technical Summary
Existing technologies are difficult to effectively treat antibiotic bacterial residue, and there are problems such as incomplete treatment, single resource utilization pathway, and poor process synergy. In particular, it is difficult to simultaneously treat solid and liquid components and convert them into useful resources.
A synergistic hydrothermal-pyrolysis and advanced oxidation treatment method was adopted, including hydrothermal pretreatment, pyrolysis conversion, preparation of fluorine-doped biochar catalyst and non-radical advanced oxidation treatment. Through four closely linked unit operations, the resource conversion of antibiotic bacterial residue was realized.
It achieves complete harmlessness of antibiotic bacterial residue, multi-path resource recovery, reduces system energy consumption and operating costs, forms an efficient internal material cycle, and solves the treatment problem of high water content and high biotoxicity.
Smart Images
Figure CN122033002A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of antibiotic bacterial residue resource utilization technology, specifically relating to a method for the synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation. Background Technology
[0002] The industrial production of antibiotics (such as kanamycin) generates a large amount of complex and difficult-to-treat fungal residue byproducts. This kanamycin-containing fungal residue has two prominent characteristics: first, it has an extremely high water content, with a solid content typically only 5%-10%, presenting as a semi-fluid slurry, making direct thermochemical treatment extremely energy-intensive; second, it contains residual antibiotics with high biotoxicity and environmental risks, with kanamycin concentrations reaching approximately 200 mg / L. If conventional methods such as landfilling or simple composting are used for disposal, the antibiotics and their active metabolites in the residue can easily seep into the soil and aquatic environment, causing pollution and continuously inducing antibiotic resistance genes in environmental microorganisms, posing a long-term and insidious threat to ecosystem security and public health. With increasingly stringent environmental regulations, the treatment of this type of hazardous waste is no longer limited to simple "elimination," but requires the simultaneous achievement of the synergistic goals of reduction (reducing the final disposal volume), harmlessness (completely eliminating antibiotic activity), and resource recovery (recovering energy and substances). However, the contradictory characteristics of high moisture content and high biotoxicity in bacterial residue pose serious challenges to the efficiency, thoroughness, and economy of existing single technical approaches, making it imperative to develop an innovative integrated technology that can systematically solve these contradictions.
[0003] Existing technologies for the treatment of antibiotic bacterial residues each have their own focus, but all have significant limitations:
[0004] Direct incineration: Although it can achieve rapid volume reduction and sterilization, it requires a large amount of auxiliary fuel for bacterial residue with high moisture content, resulting in high energy costs. Furthermore, it is prone to producing highly toxic gases such as dioxins and furans under improper combustion conditions, posing a risk of secondary pollution. At the same time, it completely fails to recover the potential resources in the waste.
[0005] Biological composting (aerobic / anaerobic): This method aims to convert microbial residue into fertilizer, but the process is lengthy and has limited antibiotic degradation efficiency. Residual antibiotics, along with drug-resistant bacteria and genes that proliferate under their selective pressure, will enter the environment with the compost products, leading to wider spread of drug-resistant gene pollution, and the environmental risks are not eradicated.
[0006] Conventional pyrolysis: Direct pyrolysis of high-moisture raw residue is extremely energy-intensive, with most of the energy consumed in moisture evaporation. Furthermore, kanamycin residue remaining in the residue may undergo incomplete decomposition during pyrolysis, producing toxic intermediates of unknown composition. The resulting biochar typically has poor pore structure and surface properties, resulting in low added value.
[0007] Advanced oxidation methods (such as the Fenton process and ozone oxidation): These methods are mainly for the degradation of organic matter in the liquid phase. For solid-liquid mixed systems like bacterial residue, solid-liquid separation is required first, and only the liquid phase can be treated. When treating high-concentration antibiotic waste liquid, the consumption of oxidants is huge, the operating cost is high, and highly toxic halogenated byproducts may be generated, without contributing to the reduction or resource recovery of the solid portion.
[0008] In summary, the common shortcomings of existing technologies are: 1) incomplete treatment, making it difficult to ensure the complete mineralization or harmless transformation of antibiotics; 2) a single or missing resource recovery pathway, failing to efficiently convert the organic matter in waste into marketable products; and 3) poor process synergy, often only addressing a single issue in reduction, harmlessness, or resource recovery, failing to form a closed-loop treatment chain. In particular, there is a lack of technical solutions capable of simultaneously and efficiently treating both solid and liquid components in kanamycin residue and converting them into useful resources. Therefore, developing an integrated process capable of synergistic treatment, deep detoxification, and multi-pathway resource recovery has become an urgent technical need to solve the environmental problems associated with kanamycin residue. Summary of the Invention
[0009] To address the shortcomings and deficiencies of existing technologies, the present invention aims to provide a method for the synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation. This invention aims to provide an integrated process for the resource-based treatment and recycling of antibiotic bacterial residue. Its core innovation lies in abandoning the traditional single-technology route and instead constructing a technology chain through four closely linked and functionally complementary unit operations, systematically solving the problem of antibiotic bacterial residue treatment.
[0010] The objective of this invention is achieved through the following technical solution:
[0011] A method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation includes the following treatment steps:
[0012] (1) Hydrothermal pretreatment: The antibiotic bacterial residue is put into a closed hydrothermal reactor and hydrothermal pretreatment is carried out in the temperature range of 120-200℃. Solid-liquid separation is performed to obtain hydrothermal solid residue and hydrothermal bacterial liquid.
[0013] (2) Pyrolysis conversion: After the hydrothermal solid residue of step (1) is dehydrated and dried, it is placed in a pyrolysis furnace under inert atmosphere protection and pyrolysis reaction is carried out in the medium temperature range of 300-550℃. The gaseous combustible gas, liquid bio-oil and solid biochar produced by the pyrolysis reaction are collected respectively.
[0014] (3) Preparation of fluorine-doped biochar catalyst: The solid biochar from step (2) is mixed with the fluorine precursor and heat-treated at a high temperature range of 600-800℃ under an inert atmosphere to obtain the fluorine-doped biochar catalyst.
[0015] (4) Non-radical advanced oxidation treatment: The hydrothermal bacterial solution from step (1) is transferred to the reactor, and persulfate oxidant and fluorine-doped biochar catalyst from step (3) are added for catalytic oxidation degradation treatment to obtain a harmless small molecule carbon source solution.
[0016] Furthermore, the antibiotic residue mentioned in step (1) is kanamycin residue with a moisture content of 90-95%.
[0017] Furthermore, the hydrothermal pretreatment time in step (1) is 1-4 h.
[0018] Furthermore, the solid-liquid separation method described in step (1) is pressure filtration, belt vacuum filtration, or centrifugal separation.
[0019] The hydrothermal pretreatment step is fundamental to all subsequent treatments, its core function being to achieve the initial transformation and property control of the materials. Under the high temperature and high pressure of the hydrothermal environment, macromolecular organic matter (such as proteins and polysaccharides) in the bacterial residue undergoes hydrolysis and pyrolysis reactions, dissolving in large quantities into the liquid phase, thus achieving a significant volume reduction (70%-80% reduction in solid phase). Simultaneously, the hydrothermal conditions effectively disrupt the molecular structure of kanamycin, achieving initial degradation (80%-90% reduction in liquid phase antibiotic concentration), significantly reducing the load on subsequent treatments. After this treatment, the dehydration performance of the residual solid phase is fundamentally improved, creating favorable conditions for subsequent efficient solid-liquid separation and pyrolysis. The products consist of two parts: one is easily dehydrated hydrothermal solid residue, and the other is hydrothermal bacterial broth containing residual antibiotics. The residual amounts of inorganic salts and macromolecular organic matter in the hydrothermal solid residue after hydrothermal pretreatment are significantly reduced, and the specific surface area and pore structure of the biochar obtained from subsequent pyrolysis are significantly improved. The prepared fluorine-doped biochar catalyst has fully exposed active sites and exhibits higher catalytic activity.
[0020] Furthermore, the dehydration and drying process described in step (2) involves drying at 80-105°C to a constant weight.
[0021] Furthermore, the pyrolysis reaction in step (2) takes 0.5-1 h.
[0022] The pyrolysis conversion step is a crucial step in achieving energy and material recovery. Under anaerobic conditions, solid organic matter undergoes thermochemical decomposition, transforming into three-phase products: gaseous combustible gas (mainly composed of CH4, CO, H2, etc., possessing fuel value), condensed and collected liquid bio-oil (which can be used as liquid fuel or chemical raw material), and solid biochar. This process not only achieves energy recovery from solid waste but also immobilizes some carbon in the biochar, providing a raw material basis for the preparation of downstream high-value-added materials, realizing the first value enhancement from waste to energy products and basic materials.
[0023] Furthermore, the fluorine precursor mentioned in step (3) is preferably polytetrafluoroethylene (PTFE).
[0024] Furthermore, the mass ratio of the solid biochar and the fluorine precursor in step (3) is 1:0.5~2.
[0025] Furthermore, the heat treatment time in step (3) is 0.5~2h.
[0026] The preparation steps of fluorine-doped biochar catalysts not only successfully incorporated fluorine into the carbon framework structure of biochar, but also induced the reconstruction of the electronic and pore structures on the surface of the carbon material. The final product, fluorine-doped biochar, is a novel carbon material with surface functionalization modification. Its unique fluorine doping sites endow the material with excellent catalytic performance, especially its ability to activate persulfate, achieving a leap from "waste" to "functional material".
[0027] Furthermore, the persulfate oxidant mentioned in step (4) is preferably sodium persulfate or potassium persulfate.
[0028] Further, the amount of persulfate oxidant added in step (4) is 0.5~5 g / L; the amount of fluorine-doped biochar catalyst added is 0.1~1 g / L.
[0029] Furthermore, the temperature of the catalytic oxidation degradation treatment in step (4) is 20~60℃ and the time is 1~6 h.
[0030] The non-radical advanced oxidation process serves as the "deep detoxification and closed-loop hub" of the process. Self-made fluorine-doped biochar is used to efficiently activate persulfate, directionally generating singlet oxygen (…). 1 The system primarily utilizes non-free radical reactive species, primarily O2. It is specifically designed for the deep oxidation of residual, recalcitrant kanamycin and its transformation products in bacterial solutions after hydrothermal pretreatment, oxidizing and decomposing them into CO2, water, and harmless inorganic small molecules, ensuring the complete mineralization or neutralization of antibiotics. The treated bacterial solution is transformed into a clean organic carbon source free of antibiotic residues, which can be safely reused in biochemical treatment systems, thus forming an internal material cycle of "waste-to-waste."
[0031] Through the series processing of the four core stages described above, the initial kanamycin bioreactor residue is completely transformed into multiple usable resources: ① a clean small-molecule carbon source solution (antibiotics are completely removed, and it can be directly reused as a safe organic carbon source in the wastewater treatment system); ② energy products (combustible gases and bio-oil); ③ high-value-added materials (fluorine-doped biochar). Particularly noteworthy is the ingenious internal material cycle: the "waste residue" (biochar) generated from its own pyrolysis is used to prepare a highly efficient catalyst, which is then used to treat the "wastewater" (containing antibiotics) generated by the process itself, perfectly embodying the circular economy concept of "treating waste with waste." This integrated process systematically solves the problem of treating high-moisture, highly toxic organic waste residue, simultaneously achieving the triple goals of reduction, harmlessness, and resource recovery.
[0032] Through the integration and innovation of the aforementioned technology chain, this invention demonstrates comprehensive advantages compared to existing single-processing methods:
[0033] (1) The harmless treatment is more thorough and safer.
[0034] A dual protection mechanism of "hydrothermal preliminary degradation" and "non-radical deep oxidation" was constructed. The hydrothermal pretreatment stage significantly reduced the total amount of antibiotics, alleviating the subsequent oxidation load; while the innovative fluorine-doped biochar / persulfate non-radical oxidation system can efficiently and selectively attack and mineralize residual antibiotic molecules at room temperature, avoiding harmful halogenated byproducts that may be generated by traditional free radical oxidation pathways, ensuring the biological safety of the effluent water quality, and truly achieving the eradication of environmental risks.
[0035] (2) Multiple resource recycling pathways and high value
[0036] Significant improvements have been made in resource recovery efficiency and value: "One waste, multiple products" full-component resource conversion has been achieved. Not only are combustible gas and bio-oil, two energy products, simultaneously recovered through pyrolysis, but more importantly, the biochar, as solid residue, has been successfully upgraded into fluorine-doped carbon material with specific catalytic functions, multiplying its value. Simultaneously, the resulting bacterial solution transforms toxic waste into a reusable carbon source, achieving internal recycling of aqueous resources. The resource yield and added value of the entire process far exceed those of traditional methods such as incineration and composting.
[0037] (3) The system energy consumption and operating costs are significantly reduced.
[0038] Hydrothermal pretreatment achieves efficient volume reduction while significantly improving the dehydration performance of the solid phase, eliminating the need for energy-intensive drying of the high-moisture raw slag during subsequent pyrolysis and drastically reducing overall energy consumption. More importantly, through an internal recycling design of "waste-to-waste," advanced oxidation catalysts are prepared using self-produced low-cost biochar and used to treat wastewater generated by the process itself. This greatly reduces external dependence on expensive commercial catalysts and large amounts of chemical oxidants, lowers operating costs, and enhances the economic feasibility of the technology.
[0039] (4) The system has a high degree of integration and is environmentally friendly.
[0040] This invention demonstrates advanced technology in system integration and environmental friendliness: it organically integrates solid-phase treatment (hydrothermal, pyrolysis), material synthesis (fluorine doping), and deep liquid-phase treatment (advanced oxidation) into a continuous process, forming a synergistic and comprehensive solution for the solid-liquid two-phase pollution of bacterial residue. The entire process is carried out in a closed and inert atmosphere, effectively controlling the emission of harmful gases; and the core technical route (non-radical oxidation, pyrolysis resource recovery) itself has a low risk of secondary pollution, conforming to the principles of green chemistry and circular economy, and providing an innovative technical paradigm for the treatment of similar high-risk organic waste residues. Attached Figure Description
[0041] Figure 1 This is a process flow diagram of a method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation in an embodiment of the present invention.
[0042] Figure 2 The image shows the SEM microstructure and EDS elemental distribution of the fluorine-doped biochar catalyst obtained in Example 1.
[0043] Figure 3 The graph shows the kanamycin degradation rate of the hydrothermal bacterial solution after non-free radical advanced oxidation treatment in step (4) of Example 1. Detailed Implementation
[0044] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.
[0045] Example 1
[0046] A method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation is illustrated in the following process flow diagram: Figure 1 As shown, the specific processing steps include the following:
[0047] (1) Hydrothermal pretreatment: The antibiotic bacterial residue (kanamycin bacterial residue from the production enterprise, with a water content of 92% and a kanamycin concentration of 200 mg / L) was put into a closed hydrothermal reactor and pretreated at 160℃ for 2 hours. After solid-liquid separation by pressure filtration, a hydrothermal solid residue with a water content of 45% and a hydrothermal bacterial solution with a kanamycin concentration of 30 mg / L were obtained. The volume of the solid residue after hydrothermal pretreatment was reduced by about 75%.
[0048] (2) Pyrolysis conversion: After drying the hydrothermal solid residue from step (1) to constant weight at 105°C, it is placed in a nitrogen-protected pyrolysis furnace and pyrolyzed at 450°C for 1 hour. The gaseous combustible gas (mainly CH4, CO, and H2), the condensed liquid bio-oil, and the solid biochar produced by the pyrolysis reaction are collected respectively. The biochar yield is about 35% of the dry mass of the bacterial residue.
[0049] (3) Preparation of fluorine-doped biochar catalyst: The solid biochar from step (2) and polytetrafluoroethylene (PTFE) were precisely weighed and thoroughly mechanically ground and mixed at a mass ratio of 1:1 to ensure uniform composite of the two phases. Then, the mixture was heat-treated at 700℃ for 1 h under nitrogen protection to obtain the fluorine-doped biochar catalyst. The SEM microstructure and EDS elemental distribution of the obtained fluorine-doped biochar catalyst are shown in the figure below. Figure 2 As shown.
[0050] (4) Non-radical advanced oxidation treatment: The hydrothermal bacterial solution from step (1) was transferred to a reactor, and sodium persulfate oxidant (2 g / L) and the fluorine-doped biochar catalyst from step (3) (0.5 g / L) were added. The reactor was then subjected to catalytic oxidation degradation treatment at 25°C for 2 h to obtain a harmless small molecule carbon source solution. High performance liquid chromatography-mass spectrometry (HPLC-MS) showed that the concentration of residual kanamycin in the solution was below the detection limit (<0.1 mg / L), indicating complete degradation (the corresponding degradation rate curve is shown in Figure 1). Figure 3 (As shown in the figure). The chemical oxygen demand removal rate reaches over 85%.
[0051] Example 2
[0052] A method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation is illustrated in the following process flow diagram: Figure 1 As shown, the specific processing steps include the following:
[0053] (1) Hydrothermal pretreatment: The antibiotic bacterial residue (same as in Example 1) was placed in a closed hydrothermal reactor and pretreated at 120°C for 4 hours. After solid-liquid separation by pressure filtration, a hydrothermal solid residue with a water content of 45% and a hydrothermal bacterial solution with a kanamycin concentration of 32 mg / L were obtained. The volume of the solid residue after hydrothermal pretreatment was reduced by approximately 68%.
[0054] (2) Pyrolysis conversion: After drying the hydrothermal solid residue from step (1) to constant weight at 100°C, it is placed in a nitrogen-protected pyrolysis furnace and pyrolyzed at 300°C for 1 hour. The gaseous combustible gas (mainly CH4, CO, and H2), the condensed liquid bio-oil, and the solid biochar produced by the pyrolysis reaction are collected respectively. The biochar yield is about 38% of the dry mass of the bacterial residue.
[0055] (3) Preparation of fluorine-doped biochar catalyst: The solid biochar from step (2) and polytetrafluoroethylene (PTFE) were accurately weighed and thoroughly mechanically ground and mixed at a mass ratio of 1:0.5 to ensure uniform composite of the two phases. Then, the mixture was heat-treated at 600℃ for 1 h under nitrogen protection to obtain the fluorine-doped biochar catalyst.
[0056] (4) Non-radical advanced oxidation treatment: The hydrothermal bacterial solution from step (1) was transferred to a reactor, and sodium persulfate oxidant (0.5 g / L) and the fluorine-doped biochar catalyst from step (3) (0.1 g / L) were added. The reactor was subjected to catalytic oxidation degradation treatment at 20°C for 6 h to obtain a harmless small molecule carbon source solution. High performance liquid chromatography-mass spectrometry (HPLC-MS) analysis showed that the kanamycin degradation rate in the solution was 99.4%, and the chemical oxygen demand (COD) removal rate was approximately 78%.
[0057] Example 3
[0058] A method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation is illustrated in the following process flow diagram: Figure 1 As shown, the specific processing steps include the following:
[0059] (1) Hydrothermal pretreatment: The antibiotic bacterial residue (same as in Example 1) was put into a closed hydrothermal reactor and pretreated at 200°C for 1 hour. After solid-liquid separation by pressure filtration, a hydrothermal solid residue with a water content of 45% and a hydrothermal bacterial solution with a kanamycin concentration of 30 mg / L were obtained. The volume of the solid residue after hydrothermal pretreatment was reduced by about 77%.
[0060] (2) Pyrolysis conversion: After drying the hydrothermal solid residue from step (1) to constant weight at 95°C, it was placed in a nitrogen-protected pyrolysis furnace and pyrolyzed at 550°C for 0.5h. The gaseous combustible gas (mainly CH4, CO, and H2), the condensed liquid bio-oil, and the solid biochar produced by the pyrolysis reaction were collected respectively. The biochar yield was about 34% of the dry mass of the bacterial residue.
[0061] (3) Preparation of fluorine-doped biochar catalyst: The solid biochar from step (2) and polytetrafluoroethylene (PTFE) were accurately weighed and thoroughly mechanically ground and mixed at a mass ratio of 1:2 to ensure uniform composite of the two phases. Then, the mixture was heat-treated at 800℃ for 0.5h under nitrogen protection to obtain the fluorine-doped biochar catalyst.
[0062] (4) Non-radical advanced oxidation treatment: The hydrothermal bacterial solution from step (1) was transferred to a reactor, and sodium persulfate oxidant (5 g / L) and the fluorine-doped biochar catalyst from step (3) (1 g / L) were added for catalytic oxidation degradation at 60°C for 1 h to obtain a harmless small molecule carbon source solution. High performance liquid chromatography-mass spectrometry (HPLC-MS) showed that the residual kanamycin concentration in the solution was below the detection limit (<0.1 mg / L), indicating complete degradation and a chemical oxygen demand (COD) removal rate of approximately 90%.
[0063] Comparative Example 1
[0064] A method for treating antibiotic bacterial residue, compared to Example 1, does not involve hydrothermal pretreatment. Results showed that the untreated original bacterial residue had a high water content and was viscous, making direct plate and frame filtration difficult and ineffective solid-liquid separation impossible. Even with forced mechanical dehydration, the filter cake still had a water content exceeding 80%, and the chemical oxygen demand and kanamycin concentration in the filtrate were similar to those of the original bacterial solution, failing to achieve volume reduction and preliminary detoxification. This indicates that hydrothermal pretreatment can effectively improve the physical properties of antibiotic bacterial residue, improve dehydration performance, increase the solid-phase reduction rate, and create favorable conditions for subsequent treatment.
[0065] Comparative Example 2
[0066] A method for treating antibiotic bacterial residue, compared with Example 1, does not perform the hydrothermal pretreatment in step (1), but directly performs the pyrolysis conversion in step (2) and the preparation of fluorine-doped biochar catalyst in step (3) by drying and pulverizing the antibiotic bacterial residue to obtain dry powder.
[0067] The results showed that the fluorine-doped biochar catalyst prepared by this method exhibited a significantly reduced degradation efficiency of kanamycin in the hydrothermal bacterial solution during step (4) (the degradation rate was only 60% within 2 hours under the same conditions). This is because, in the bacterial residue without hydrothermal pretreatment, a large amount of inorganic salts and incompletely hydrolyzed macromolecular organic matter remained in the dry-based powder. These substances would clog the pores of the biochar during pyrolysis or affect the graphitization degree of the carbon material, resulting in a lower specific surface area and less developed pore structure in the final biochar. The fluorine-doped catalyst prepared using this as a support had insufficient exposure of active sites, and its catalytic activity was far lower than that of Example 1. This comparative example demonstrates that hydrothermal pretreatment not only improves physical properties but also has a decisive impact on the quality of the final catalyst.
[0068] Comparative Example 3
[0069] A method for treating antibiotic bacterial residue, compared with Example 1, involves the hydrothermal solid residue not undergoing the hydrothermal pretreatment in step (1) and the pyrolysis conversion in step (2), but instead directly preparing the dry-based powder obtained by drying and pulverizing the antibiotic bacterial residue into a fluorine-doped biochar catalyst in step (3).
[0070] The results show that the product prepared by this method has a significantly different structure and performance compared to the fluorine-doped biochar catalyst in Example 1. Because it has not undergone pyrolytic carbonization, the dry powder mainly consists of incompletely decomposed bacterial organic matter. During high-temperature processing with PTFE, a large amount of organic matter decomposes, failing to form a carbon material with a stable carbon skeleton and abundant pore structure. The resulting product has a very low specific surface area and poor fluorine doping efficiency, essentially lacking the ability to activate persulfate, and failing to effectively degrade kanamycin in step (4). This comparative example strongly demonstrates that the pyrolytic conversion step is the foundation for preparing high-performance biochar catalysts, and the coupling of hydrothermal pretreatment and pyrolysis is a necessary prerequisite for the efficient and directional conversion of carbon sources in bacterial residue into functional materials.
[0071] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. A method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation, characterized in that... The processing steps include the following: (1) Hydrothermal pretreatment: The antibiotic bacterial residue is put into a closed hydrothermal reactor and hydrothermal pretreatment is carried out in the temperature range of 120-200℃. Solid-liquid separation is performed to obtain hydrothermal solid residue and hydrothermal bacterial liquid. (2) Pyrolysis conversion: After the hydrothermal solid residue of step (1) is dehydrated and dried, it is placed in a pyrolysis furnace under inert atmosphere protection and pyrolysis reaction is carried out in the medium temperature range of 300-550℃. The gaseous combustible gas, liquid bio-oil and solid biochar produced by the pyrolysis reaction are collected respectively. (3) Preparation of fluorine-doped biochar catalyst: The solid biochar from step (2) is mixed with the fluorine precursor and heat-treated at a high temperature range of 600-800℃ under an inert atmosphere to obtain the fluorine-doped biochar catalyst. (4) Non-radical advanced oxidation treatment: The hydrothermal bacterial solution from step (1) is transferred to the reactor, and persulfate oxidant and fluorine-doped biochar catalyst from step (3) are added for catalytic oxidation degradation treatment to obtain a harmless small molecule carbon source solution.
2. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The antibiotic residue mentioned in step (1) is kanamycin residue with a moisture content of 90-95%.
3. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The hydrothermal pretreatment time in step (1) is 1-4 hours; the solid-liquid separation method is pressure filtration, belt vacuum filtration or centrifugal separation.
4. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The dehydration and drying process in step (2) involves drying at 80-105℃ to constant weight; the pyrolysis reaction takes 0.5-1h.
5. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The fluorine precursor mentioned in step (3) is polytetrafluoroethylene.
6. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The mass ratio of the solid biochar and the fluorine precursor in step (3) is 1:0.5-2.
7. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The heat treatment time in step (3) is 0.5-2 hours.
8. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The persulfate oxidant mentioned in step (4) is sodium persulfate or potassium persulfate.
9. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The amount of persulfate oxidant added in step (4) is 0.5-5 g / L; the amount of fluorine-doped biochar catalyst added is 0.1-1 g / L.
10. The method for synergistic treatment of antibiotic bacterial residue based on hydrothermal-pyrolysis and advanced oxidation according to claim 1, characterized in that: The temperature of the catalytic oxidation degradation treatment in step (4) is 20~60℃ and the time is 1~6h.