Microbial remediation method and microbial remediation system

Abstract

The invention discloses a microbial remediation method and a microbial remediation system. The microbial remediation method comprises the following steps: collecting samples from a contaminated site, carrying out enrichment culture, screening and domestication to obtain various microbial strains, preparing a composite microbial agent according to a specific ratio, carrying out carrier immobilization treatment to form immobilized microbial particles, applying the immobilized microbial particles to soil in the modes of strip application, hole application and the like according to the contamination condition, or filling a suspended filler and putting the suspended filler into a water body. And environmental parameters are monitored in real time, and accurate regulation and control are performed to promote microorganisms to degrade pollutants. The microbial remediation system covers microbial culture and microbial agent preparation, putting and distribution, monitoring and regulation modules and the like, and automation and intelligentization of the whole process are achieved. The method is high in remediation efficiency, high in adaptability, low in cost, environmentally friendly and capable of effectively solving the problem of soil and water pollution.

Description

Technical Field

[0001] The present invention relates to the field related to environmental remediation, and specifically to a microbial remediation method and a microbial remediation system. Background Art

[0002] Traditional physical remediation methods, such as soil washing, topsoil replacement method, etc., have large engineering quantities, high costs, and may also damage the original soil structure; chemical remediation methods, such as chemical oxidation-reduction methods, although having certain effects, are prone to introducing new chemical substances and causing secondary pollution. Microbial remediation technology has become the research focus in the field of environmental remediation due to its advantages of being green and environmentally friendly, relatively low cost, and in-situ remediation. However, existing microbial remediation technologies have problems such as the microbial activity being easily affected by the environment, long remediation cycles, and poor remediation effects on complex pollution. There is an urgent need for a more efficient and stable microbial remediation method and system. Summary of the Invention

[0004] The purpose of the present invention is to provide a microbial remediation method and a microbial remediation system to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A microbial remediation method, including the following steps: Step 1, Preparation of microbial complex inoculant: Samples are collected from the polluted site and the surrounding environment, and through enrichment culture, screening, and domestication, a variety of microbial strains with high-efficiency degradation ability for target pollutants are obtained. The above strains are mixed in a specific proportion to make a microbial complex inoculant; Step 2, Carrier immobilization treatment: Select carrier materials with good biocompatibility and strong adsorption performance, specifically including chitosan, sodium alginate, and porous ceramsite. The microbial complex inoculant is combined with the carrier material through embedding and adsorption methods to form immobilized microbial particles; Step 3, Remediation implementation: For soil pollution, according to the soil texture, pollution degree, and pollutant types, determine the application amount and application method of the immobilized microbial particles. Specifically, use the strip application and hole application methods to evenly mix the immobilized microbial particles into the soil to a depth of 20 - 30 cm; for water pollution, load the immobilized microbial particles into a special floating filler and put it into the polluted water area, and achieve full contact between the microorganisms and the pollutants through water flow; Step 4, Environmental regulation: During the remediation process, real-time monitor environmental parameters such as the temperature, pH value, dissolved oxygen, and redox potential of the soil or water body. According to the optimal conditions for microbial growth and metabolism, precisely regulate the environmental parameters by adding acid-base regulators, aeration, and adding nutrients to provide a suitable environment for the growth of microorganisms and the degradation of pollutants.

[0006] Preferably, the specific steps for preparing the microbial complex agent in step 1 are as follows: Step 11: According to the type and distribution of the target pollutants, determine multiple representative sampling points in the polluted site and its surrounding environment. Specifically, for soil pollution, set sampling points in the most severely polluted area, the polluted edge area, and the surrounding unpolluted area that may have potential impacts; for water pollution, sample at different depths and different water flow positions. Step 12: For soil samples: Use a sterile soil drill to collect soil at a depth of 0 - 20 cm, collect 500 g of soil at each sampling point, mix the soil from several sampling points evenly, and put it into a sterile plastic bag; for water samples: Use a sterile sampling bottle to collect water samples, collect 1 L of water sample at each sampling point, also mix the water samples from multiple sampling points, and seal and store them. Step 13: Medium preparation: Prepare a corresponding enrichment medium according to the nature of the target pollutants in the samples collected in step 12. Step 14: Inoculation and cultivation: Inoculate the collected samples into the enrichment medium at an inoculation amount of 10% by volume ratio, and cultivate them in a shaker at 30°C and 150 r / min for 7 - 10 days. During the cultivation process, regularly observe the turbidity and color changes of the medium to judge the growth of microorganisms. Step 15: Screening: After appropriately diluting the enrichment medium, inoculate it onto a solid medium containing the target pollutants by the streak plate method to obtain pure cultures; inoculate the above purified strains into a liquid medium containing the target pollutants respectively, cultivate for a certain time under the same cultivation conditions, then use gas chromatography or liquid chromatography to measure the residual amount of the target pollutants in the culture solution, calculate the degradation rate, and select the strains with higher degradation rates as the objects for subsequent research. Step 16: Domestication: Inoculate the selected strains into a medium containing a lower concentration of the target pollutants, and after cultivating for a period of time, transfer the culture solution to a medium containing a higher concentration of the target pollutants, and repeat this process to gradually improve the tolerance and degradation ability of the strains to the target pollutants; after multiple transfer cultivations, perform multi-generation cultivation on the strains to stabilize their degradation performance. Step 17: Identify the domesticated strains to determine their genera and species; then, according to the degradation ability, growth characteristics of different microbial strains to the target pollutants, and the synergistic effect factors between them, determine the appropriate ratio; accurately measure the bacterial solutions of each strain according to the determined ratio, mix them evenly, and then the microbial complex agent can be prepared.

[0007] Preferably, the specific content of the remediation implementation in step 3 is as follows: For soil pollution, the specific implementation is as follows: Soil analysis: Before applying the immobilized microbial particles, a comprehensive analysis of the polluted soil is required. Soil texture analysis: Through soil sampling and laboratory analysis, determine the texture type of the soil; Pollution degree assessment: Use chemical analysis methods or instrumental analysis methods to measure the content of pollutants in the soil and assess the pollution degree; Pollutant type identification: Identify the types of pollutants in the soil; Selection of application method: According to the soil texture, pollution degree, and types of pollutants, select a suitable application method. Specifically, for the remediation of large areas of farmland or forest land pollution and when the soil texture is relatively uniform, use the strip application method to evenly mix the immobilized microbial particles into the soil. For areas where the pollution point sources are relatively concentrated, select the hole application method to evenly mix the immobilized microbial particles into the soil; For water pollution, the specific implementation is as follows: Loading of special suspension fillers, load the immobilized microbial particles into the suspension fillers according to a certain proportion. After loading, ensure that the immobilized microbial particles are evenly distributed in the suspension fillers; Determination of the placement location, according to the distribution of water pollution and the water flow characteristics, determine the placement location of the immobilized microbial particles. Specifically, place the special suspension fillers in the areas with relatively severe pollution. At the same time, consider the depth and flow rate of the water body to prevent the immobilized microbial particles from being washed away by the water flow or deposited at the bottom of the water.

[0008] Preferably, the specific steps of environmental regulation in step 4 are as follows: Step 41, Establishment of the monitoring system Soil monitoring: For soil temperature monitoring, select high-precision soil temperature sensors. According to the size of the soil pollution area, bury the sensors in the soil at a depth of 15 - 20 cm in a grid layout, and set a monitoring point every 5 - 10 square meters; For the pH detection of the soil, where the pH sensor uses a corrosion-resistant glass electrode type sensor, and the pH sensor is also buried in the soil according to the above layout method, with a depth of about 10 - 15 cm to ensure that it can accurately reflect the soil acidity and alkalinity; Select a dissolved oxygen sensor and install it in a pre-buried breathable casing in the soil. The casing ensures good air permeability to accurately measure the dissolved oxygen content in the soil, and the monitoring points are set the same as the temperature sensors; Use an oxidation-reduction potential sensor to detect the oxidation-reduction state of the soil, where the oxidation-reduction potential sensor is buried in the soil at a depth of 10 - 15 cm, and one is arranged every 3 - 5 meters; Water body monitoring: Select a waterproof temperature sensor to monitor the water temperature. The waterproof temperature sensor is installed at different water layer depths. Specifically, a monitoring point is set every 5 - 10 meters to ensure that the temperature changes in different water layers can be monitored; Monitor the pH value of the water body. The pH sensor is installed at a position where the water flow in the water body is relatively stable, avoiding installation near the water inlet or outlet. Monitoring points are set at intervals of 5 - 10 meters; Monitor the dissolved oxygen in the water body. The dissolved oxygen sensor is installed at different depths and positions in the water body, especially in areas with relatively serious pollution, which need to be key arranged. The buoy type or submersible installation method is adopted, and a monitoring point is set every 3 - 5 meters; Monitor the redox state of the water body. The redox potential sensor is installed in the water body near the pollution source or areas where redox reactions are likely to occur; Step 42, Setting environmental parameter thresholds: According to the growth and metabolic characteristics of different microbial complex agents, determine the appropriate ranges of temperature, pH value, dissolved oxygen and redox potential in the soil or water body as thresholds; Step 43, Real-time monitoring and data analysis: The data analysis software analyzes the collected data and compares it with the pre-set thresholds to determine whether the environmental parameters are within the appropriate range. When a certain parameter exceeds the threshold range, the system automatically issues an alarm signal; Step 44, Implementing control measures Temperature control: When the soil temperature is too low, use a ground heating wire to heat. According to the soil area and temperature requirements, reasonably arrange the ground heating wire, and automatically control the heating temperature through a temperature controller to gradually raise the soil temperature to the appropriate range; If the soil temperature is too high, use a sunshade net to cover or spray water to cool down. The shading rate of the sunshade net is selected according to the actual situation. Spraying water adopts drip irrigation or sprinkler irrigation methods to keep the soil surface moist and reduce the soil temperature; When the water temperature is too low, install a heating rod in the water body or use a solar heating system. When the water temperature is too high, increase the water fluidity. Specifically, turn on the circulation pump to mix hot water and cold water to reduce the water temperature; pH value control: When the soil pH value is too low, lime can be added for adjustment. When the soil pH value is too high, add sulfur powder or ferrous sulfate acidic substances; When the water body pH value is too low, add alkaline substances such as sodium hydroxide and sodium carbonate to the water body. When the water body pH value is too high, add acidic substances such as hydrochloric acid and sulfuric acid for neutralization; Dissolved oxygen control: When the dissolved oxygen content in the soil is insufficient, use a soil ventilation system. Specifically, bury ventilation pipes with evenly distributed small holes on them, and pass air into the pipes through a blower to make the air diffuse into the surrounding soil to increase the dissolved oxygen content in the soil; When the dissolved oxygen content in the water body is insufficient, use aeration equipment for oxygenation; Redox potential regulation: If the soil redox potential is too high, reducing substances are added to the soil. When the soil redox potential is too low, aeration or the addition of oxidizing substances is used for adjustment; when the water body redox potential is too high, reducing substances such as sodium sulfite and sodium thiosulfate are added. When the water body redox potential is too low, it is adjusted by aeration or the addition of oxidizing substances such as potassium permanganate; Step 45: After the control measures have been implemented for a preset period of time, the environmental parameters of the soil or water body are monitored and analyzed again to evaluate the control effect.

[0009] Preferably, a microbial remediation system includes a microbial culture and inoculant preparation module, a dosing and distribution module, and a monitoring and control module. The microbial culture and inoculant preparation module is equipped with professional microbial culture equipment for the screening, cultivation, and propagation of microbial strains. At the same time, the microbial culture and inoculant preparation module is provided with a production line for inoculant mixing and immobilization to achieve the efficient preparation and immobilization treatment of microbial composite inoculants; for soil remediation, the dosing and distribution module designs an automated soil spraying device to accurately control the application rate and application location of immobilized microbial particles according to preset parameters. For water body remediation, the dosing and distribution module is provided with an adjustable suspended filler dosing device that can flexibly adjust the dosing depth and distribution density of suspended fillers according to factors such as water body flow rate and depth; the monitoring and control module uses sensor technology to collect real-time data on various environmental parameters and pollutant concentrations in the soil or water body, and transmits the data to the central control system through a wireless transmission module. The central control system analyzes and processes the data based on preset algorithms and models, and automatically controls the control equipment.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: The microbial composite inoculant used in the present invention mixes microbial strains with high degradation ability for target pollutants in a specific ratio. These microorganisms can play a synergistic role, decomposing and transforming pollutants from different angles, greatly broadening the range of pollutant degradation. Compared with traditional single-microbial remediation methods, the degradation efficiency is significantly improved, effectively shortening the time required for pollution remediation. For example, when treating petroleum hydrocarbon-contaminated soil, traditional methods may take months or even years to achieve a certain remediation effect, while the method of the present invention may only take a few weeks to significantly reduce the pollutant content; through carrier immobilization treatment, the microbial composite inoculant is combined with a carrier material with good biocompatibility and strong adsorption performance to form immobilized microbial particles. This treatment method can not only effectively protect the microorganisms, enabling them to maintain high activity and stability in a complex environment, but also increase the contact area and contact time between the microorganisms and pollutants, further improving the degradation effect on pollutants and being able to more thoroughly remove pollutants in the soil and water body; The microbial composite bacterium agent of the present invention is obtained through a series of processes such as enrichment culture, screening, and domestication from samples collected from contaminated sites and the surrounding environment. Through long-term natural selection and artificial domestication, these microorganisms have good adaptability to the local polluted environment, can survive and reproduce under complex pollution conditions, and play an efficient degradation role. Whether facing the combined pollution of multiple pollutants coexisting or in soil with different textures or water environment with different characteristics, it can exhibit good remediation performance; during the remediation process, environmental parameters such as the temperature, pH value, dissolved oxygen, and redox potential of the soil or water are monitored in real time, and precise regulation is carried out by means such as adding acid-base regulators, aeration, and adding nutrients. This enables the microorganisms to grow and metabolize in a relatively stable and suitable environment, enhancing their tolerance to environmental changes and ensuring the continuous and stable progress of the remediation process; The microbial remediation method of the present invention is an in-situ remediation technology, which does not require large-scale excavation, transportation, and treatment of contaminated soil or water, greatly reducing the input of manpower, material resources, and financial resources. At the same time, by precisely regulating environmental parameters, nutrients and energy can be reasonably utilized, avoiding unnecessary waste and reducing resource consumption during the remediation process; the microbial remediation system of the present invention realizes the full-process automation and intelligence from bacterium agent preparation, delivery, monitoring to regulation. Automated equipment and intelligent control systems can improve work efficiency, reduce errors and labor intensity of manual operations, and reduce labor costs. Moreover, the modular design of the system makes the installation, maintenance, and upgrade of the equipment more convenient, further reducing the usage cost of the equipment. Brief Description of the Drawings

[0011] Figure 1 It is a schematic flow chart of the method of the present invention; Figure 2 It is a schematic structural diagram of the system of the present invention. Detailed Embodiments

[0012] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Embodiment

[0013] Please refer to Figure 1 , the present invention provides a technical solution: a microbial remediation method includes the following steps: Step 1: Preparation of microbial composite inoculant: Samples are collected from the polluted site and its surrounding environment, and through enrichment culture, screening, and domestication, a variety of microbial strains with high degradation ability for the target pollutant are obtained. The above strains are mixed in a specific ratio to prepare a microbial composite inoculant; Step 2: Carrier immobilization treatment: Carrier materials with good biocompatibility and strong adsorption performance are selected, specifically including chitosan, sodium alginate, and porous ceramsite. The microbial composite inoculant is combined with the carrier material through embedding and adsorption methods to form immobilized microbial particles; Step 3: Remediation implementation: For soil pollution, according to the soil texture, pollution degree, and pollutant types, determine the application rate and application method of the immobilized microbial particles. Specifically, use the band application and hole application methods to evenly mix the immobilized microbial particles into the soil, with a depth of 20 - 30 cm; for water pollution, load the immobilized microbial particles into a special suspension filler and put it into the polluted water area to achieve sufficient contact between the microorganisms and pollutants through water flow; Step 4: Environmental regulation: During the remediation process, monitor the environmental parameters of soil or water temperature, pH value, dissolved oxygen, and redox potential in real time. According to the optimal conditions for microbial growth and metabolism, precisely regulate the environmental parameters by adding acid-base regulators, aeration, and adding nutrients to provide a suitable environment for the growth of microorganisms and pollutant degradation.

[0014] Further, the specific steps for the preparation of the microbial composite inoculant in Step 1 are as follows: Step 11: According to the type and distribution of the target pollutant, determine multiple representative sampling points in the polluted site and its surrounding environment. Specifically, for soil pollution, set sampling points in the most severely polluted area, the pollution edge area, and the surrounding unpolluted but potentially affected area; for water pollution, sample at different depths and different water flow positions; Step 12: For soil samples: Use a sterile soil drill to collect soil at a depth of 0 - 20 cm, collect 500 g of soil at each sampling point, mix the soil from several sampling points evenly, and put it into a sterile plastic bag; for water samples: Use a sterile sampling bottle to collect water samples, collect 1 L of water sample at each sampling point, and also mix the water samples from multiple sampling points and seal them for storage; Step 13: Medium preparation: According to the nature of the target pollutant in the samples collected in Step 12, prepare a corresponding enrichment medium; taking petroleum hydrocarbon pollution as an example, the medium formula is as follows: Basic components: Ammonium nitrate (NH4NO3): 1 g, Potassium dihydrogen phosphate (KH2PO4): 0.5 g, Dipotassium hydrogen phosphate (K2HPO4): 1.5 g, Magnesium sulfate (MgSO4・7H2O): 0.2 g, Calcium chloride (CaCl2): 0.01 g, Trace element solution: 1 ml (the trace element solution contains boric acid, manganese sulfate, zinc sulfate, copper sulfate, etc.) and Distilled water: 1000 ml; Carbon source: An appropriate amount of petroleum hydrocarbon is added as the sole carbon source, and its concentration is determined according to the pollution degree and experimental requirements, generally 1 - 5 g / L; pH value: The pH value of the culture medium is adjusted to 7.0 - 7.2 with sodium hydroxide (NaOH) or hydrochloric acid (HCl). Step 14, Inoculation and cultivation: The collected sample is inoculated into the enrichment medium at an inoculation amount of 10% by volume ratio, and cultivated in a shaker at 30 °C and 150 r / min for 7 - 10 days. During the cultivation process, the turbidity and color change of the culture medium are observed regularly to judge the growth situation of microorganisms. Step 15, Screening: After appropriately diluting the enrichment medium, it is inoculated onto the solid medium containing the target pollutant by the method of streaking for isolation to obtain pure cultures; The above purified strains are respectively inoculated into the liquid medium containing the target pollutant, and after culturing for a certain time under the same culture conditions, the residual amount of the target pollutant in the culture solution is measured by gas chromatography or liquid chromatography, and the degradation rate is calculated. The strains with higher degradation rates are selected as the objects for subsequent research. Step 16, Domestication: The selected strains are inoculated into the medium containing a lower concentration of the target pollutant. After culturing for a period of time, the culture solution is transferred to the medium containing a higher concentration of the target pollutant, and this is repeated to gradually improve the tolerance and degradation ability of the strains to the target pollutant; After multiple transfer cultivations, the strains are cultured for multiple generations to stabilize their degradation performance. Step 17, Identify the domesticated strains to determine their genera and species; Then, according to the degradation ability, growth characteristics of different microbial strains to the target pollutant and the synergistic effect factors among them, determine the appropriate ratio; According to the determined ratio, accurately measure the bacterial solutions of each strain, mix them evenly, and then a microbial composite agent can be prepared.

[0015] Furthermore, the specific content of the remediation implementation in step 3 is as follows: For soil pollution, the specific implementation is as follows: Soil analysis: Before applying the immobilized microbial particles, a comprehensive analysis of the polluted soil is required. Soil texture analysis: Determine the texture type of the soil through soil sampling and laboratory analysis; Pollution degree assessment: Use chemical analysis methods or instrumental analysis methods to measure the content of pollutants in the soil and assess the pollution degree; Identification of pollutant types: Identify the types of pollutants in the soil; Selection of application methods: Select appropriate application methods according to the soil texture, pollution degree, and pollutant types. Specifically, for the pollution remediation of large areas of farmland or forest land, and in the case of relatively uniform soil texture, use the strip application method to evenly mix the immobilized microbial particles into the soil. For areas where the pollution point sources are relatively concentrated, select the hole application method to evenly mix the immobilized microbial particles into the soil; For water pollution, the specific implementation is as follows: Loading of special suspension fillers, load the immobilized microbial particles into the suspension fillers according to a certain proportion. After loading, ensure that the immobilized microbial particles are evenly distributed in the suspension fillers; Determination of the placement position, determine the placement position of the immobilized microbial particles according to the distribution of water pollution and the water flow characteristics. Specifically, put the special suspension fillers into the areas with relatively severe pollution. At the same time, consider the depth and flow rate of the water body to prevent the immobilized microbial particles from being washed away by the water flow or deposited at the bottom of the water Furthermore, the specific steps of environmental regulation in step 4 are as follows: Step 41, Establishment of the monitoring system Soil monitoring: For soil temperature monitoring, select high-precision soil temperature sensors. According to the size of the soil pollution area, bury the sensors into the soil at a depth of 15 - 20 cm in a grid layout, and set a monitoring point every 5 - 10 square meters; For the pH detection of the soil, the pH sensor uses a corrosion-resistant glass electrode type sensor, and the pH sensor is also buried into the soil according to the above layout method, with a depth of about 10 - 15 cm to ensure that the soil acidity and alkalinity can be accurately reflected; Select a dissolved oxygen sensor and install it in a pre-buried breathable casing in the soil. The casing ensures good air permeability to accurately measure the dissolved oxygen content in the soil, and the monitoring points are set in the same way as the temperature sensors; Use an oxidation-reduction potential sensor to detect the oxidation-reduction state of the soil. The oxidation-reduction potential sensor is buried into the soil at a depth of 10 - 15 cm, and one is arranged every 3 - 5 meters; Water body monitoring: Select waterproof temperature sensors to monitor the water temperature. The waterproof temperature sensors are installed at different water depths. Specifically, a monitoring point is set every 5 - 10 meters to ensure that the temperature changes in different water layers can be monitored; monitor the pH value of the water body. The pH sensor is installed at a position in the water body where the water flow is relatively stable, avoiding installation near the water inlet or outlet, and setting monitoring points at intervals of 5 - 10 meters; monitor the dissolved oxygen in the water body. The dissolved oxygen sensor is installed at different depths and positions in the water body, especially in areas with relatively serious pollution, which need to be key arranged. The buoy type or submersible installation method is adopted, and a monitoring point is set every 3 - 5 meters; monitor the redox state of the water body. The redox potential sensor is installed in the water body near the pollution source or areas prone to redox reactions; Step 42: Setting environmental parameter thresholds: According to the growth and metabolic characteristics of different microbial complex agents, determine the suitable ranges of temperature, pH value, dissolved oxygen and redox potential in the soil or water body as thresholds; Step 43: Real-time monitoring and data analysis: The data analysis software analyzes the collected data, compares it with the pre-set thresholds, and judges whether the environmental parameters are within the suitable ranges. When a certain parameter exceeds the threshold range, the system automatically issues an alarm signal; Step 44: Implementing control measures Temperature control: When the soil temperature is too low, use the method of laying heating cables to heat. According to the soil area and temperature requirements, reasonably arrange the heating cables, and automatically control the heating temperature through a thermostat to gradually raise the soil temperature to the suitable range; if the soil temperature is too high, use the method of covering with a sunshade net or spraying water to cool down. The shading rate of the sunshade net is selected according to the actual situation. Spraying water adopts the drip irrigation or sprinkler irrigation method to keep the soil surface moist and reduce the soil temperature; when the water temperature is too low, install a heating rod in the water body or use a solar heating system. When the water temperature is too high, increase the water fluidity. Specifically, turn on the circulation water pump to mix hot water and cold water to reduce the water temperature; pH value control: When the soil pH value is too low, lime can be added for adjustment. When the soil pH value is too high, add sulfur powder or ferrous sulfate acidic substances; when the water body pH value is too low, add sodium hydroxide, sodium carbonate alkaline substances to the water body. When the water body pH value is too high, add hydrochloric acid, sulfuric acid acidic substances for neutralization; Dissolved oxygen control: When the dissolved oxygen content in the soil is insufficient, use a soil ventilation system. Specifically, bury ventilation pipes with evenly distributed small holes on them, and introduce air into the pipes through a blower to make the air diffuse into the surrounding soil to increase the dissolved oxygen content in the soil; when the dissolved oxygen content in the water body is insufficient, use aeration equipment for oxygenation; Redox potential regulation: If the soil redox potential is too high, reducing substances are added to the soil. When the soil redox potential is too low, aeration or the addition of oxidizing substances is used for adjustment; when the water body redox potential is too high, reducing substances such as sodium sulfite and sodium thiosulfate are added. When the water body redox potential is too low, it is adjusted by aeration or the addition of oxidizing substances such as potassium permanganate; Step 45: After a preset period of time for implementing the regulation measures, the environmental parameters of the soil or water body are monitored and analyzed again to evaluate the regulation effect. Example

[0016] Please refer to Figure 2 , a microbial remediation system, including a microbial culture and inoculum preparation module, a delivery and distribution module, and a monitoring and regulation module. The microbial culture and inoculum preparation module is equipped with professional microbial culture equipment for screening, culturing, and propagating microbial strains. At the same time, the microbial culture and inoculum preparation module sets up an inoculum mixing and immobilization production line to achieve the efficient preparation and immobilization treatment of microbial composite inoculants; for soil remediation, the delivery and distribution module designs an automated soil pesticide application device to accurately control the application amount and application location of immobilized microbial particles according to preset parameters. For water body remediation, the delivery and distribution module sets up an adjustable suspended packing delivery device that can flexibly adjust the delivery depth and distribution density of suspended packing according to factors such as water body flow rate and depth; the monitoring and regulation module uses sensor technology to collect real-time data on various environmental parameters and pollutant concentrations in the soil or water body, and transmits the data to the central control system through a wireless transmission module. Among them, the central control system analyzes and processes the data based on preset algorithms and models, and automatically controls the regulation equipment.

[0017] The microbial complex agent adopted in the present invention mixes microbial strains with high-efficiency degradation ability for target pollutants in a specific proportion. These microorganisms can play a synergistic role, decomposing and transforming pollutants from different perspectives, greatly broadening the degradation range of pollutants. Compared with the traditional single-microbial remediation method, the degradation efficiency is significantly improved, thus effectively shortening the time required for pollution remediation. For example, when treating petroleum hydrocarbon-contaminated soil, the traditional method may take months or even years to achieve a certain remediation effect, while the method of the present invention may only take a few weeks to significantly reduce the pollutant content; through carrier immobilization treatment, the microbial complex agent is combined with a carrier material with good biocompatibility and strong adsorption performance to form immobilized microbial particles. This treatment method can not only effectively protect the microorganisms, enabling them to maintain high activity and stability in a complex environment, but also increase the contact area and contact time between the microorganisms and the pollutants, further improving the degradation effect of the pollutants and being able to more thoroughly remove the pollutants in soil and water bodies; the microbial complex agent of the present invention is obtained through a series of processes such as enrichment culture, screening, and domestication from samples collected from contaminated sites and the surrounding environment. These microorganisms have good adaptability to the local polluted environment after long-term natural selection and artificial domestication, can survive and reproduce under complex pollution conditions, and play an efficient degradation role. Whether facing complex pollution with multiple pollutants coexisting or in soil with different textures or water bodies with different characteristics, it can exhibit good remediation performance; during the remediation process, environmental parameters such as the temperature, pH value, dissolved oxygen, and redox potential of the soil or water body are monitored in real time, and precise regulation is carried out by means such as adding acid-base regulators, aeration, and adding nutrients. This enables the microorganisms to grow and metabolize in a relatively stable and suitable environment, enhancing their tolerance to environmental changes and ensuring the continuous and stable progress of the remediation process; the microbial remediation method of the present invention is an in-situ remediation technology, which does not require large-scale excavation, transportation, and treatment of contaminated soil or water bodies, greatly reducing the input of human, material, and financial resources. At the same time, through precise regulation of environmental parameters, nutrients and energy can be reasonably utilized, avoiding unnecessary waste and reducing resource consumption during the remediation process; the microbial remediation system of the present invention realizes the full-process automation and intelligence from agent preparation, delivery, monitoring to regulation. Automated equipment and intelligent control systems can improve work efficiency, reduce errors and labor intensity in manual operations, and reduce labor costs. Moreover, the modular design of the system makes the installation, maintenance, and upgrade of the equipment more convenient, further reducing the use cost of the equipment.

[0018] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A microbial remediation method, characterized in that, It includes the following steps: Step 1, Preparation of microbial composite inoculant: Samples are collected from the polluted site and its surrounding environment, and through enrichment culture, screening, and domestication, multiple microbial strains with high-efficiency degradation ability for target pollutants are obtained. The above-mentioned strains are mixed in a specific ratio to prepare a microbial composite inoculant; Step 2, Carrier immobilization treatment: Select carrier materials with good biocompatibility and strong adsorption performance, specifically including chitosan, sodium alginate, and porous ceramsite. The microbial composite inoculant is combined with the carrier material through embedding and adsorption methods to form immobilized microbial particles; Step 3, Remediation implementation: For soil pollution, according to the soil texture, pollution degree, and pollutant types, determine the application amount and application method of the immobilized microbial particles. Specifically, use the strip application and hole application methods to evenly mix the immobilized microbial particles into the soil to a depth of 20 - 30 cm; for water pollution, load the immobilized microbial particles into a special floating packing material and put them into the polluted water area, and achieve sufficient contact between microorganisms and pollutants through water flow; Step 4, Environmental regulation: During the remediation process, real-time monitor the environmental parameters such as temperature, pH value, dissolved oxygen, and redox potential of the soil or water body. According to the optimal conditions for microbial growth and metabolism, precisely regulate the environmental parameters by adding acid-base regulators, aeration, and adding nutrients to provide a suitable environment for the growth of microorganisms and the degradation of pollutants.

2. The microbial remediation method according to claim 1, wherein: The specific steps for the preparation of the microbial composite inoculant in Step 1 are as follows: Step 11, According to the type and distribution of the target pollutants, determine multiple representative sampling points in the polluted site and its surrounding environment. Specifically, for soil pollution, set sampling points in the most severely polluted area, the pollution edge area, and the surrounding unpolluted but potentially affected area; for water pollution, sample at different depths and different water flow positions; Step 12, For soil samples: Use a sterile soil drill to collect soil at a depth of 0 - 20 cm, collect 500 g of soil at each sampling point, mix the soil from several sampling points evenly, and put it into a sterile plastic bag; for water samples: Use a sterile sampling bottle to collect water samples, collect 1 L of water sample at each sampling point, and also mix the water samples from multiple sampling points and seal them for storage; Step 13, Medium preparation: Prepare a corresponding enrichment medium according to the nature of the target pollutants in the samples collected in Step 12; Step 14, Inoculation and culture: Inoculate the collected samples into the enrichment medium at an inoculation amount of 10% by volume ratio, and culture them in a shaker at 30 °C and 150 r / min for 7 - 10 days. During the culture process, regularly observe the turbidity and color changes of the medium to judge the growth of microorganisms; Step 15, Screening: After appropriately diluting the enrichment medium, inoculate it onto a solid medium containing the target pollutant by the method of streaking plate to obtain pure cultures; inoculate the purified strains mentioned above into a liquid medium containing the target pollutant respectively, after culturing for a certain period of time under the same culture conditions, use gas chromatography or liquid chromatography to measure the residual amount of the target pollutant in the culture solution, calculate the degradation rate, and select the strains with higher degradation rates as the objects for subsequent research; Step 16, Domestication: Inoculate the screened strains into a medium containing a lower concentration of the target pollutant, after culturing for a period of time, transfer the culture solution to a medium containing a higher concentration of the target pollutant, and repeat this process step by step to gradually improve the tolerance and degradation ability of the strains to the target pollutant; After multiple transfer cultures, perform multi-generation cultures on the strains to stabilize their degradation performance; Step 17, Identify the domesticated strains to determine their genera and species; then, according to the degradation ability, growth characteristics of different microbial strains to the target pollutant and the synergistic effect factors among them, determine the appropriate ratio; accurately measure the bacterial suspensions of each strain according to the determined ratio, and after mixing evenly, a microbial composite agent can be prepared.

3. The microbial remediation method according to claim 1, characterized in that: The specific content of the remediation implementation in Step 3 is as follows: For soil pollution, the specific implementation is as follows: Soil analysis: Before applying the immobilized microbial particles, it is necessary to conduct a comprehensive analysis of the polluted soil. Soil texture analysis: Determine the texture type of the soil through soil sampling and laboratory analysis; Pollution degree assessment: Use chemical analysis methods or instrumental analysis methods to measure the content of pollutants in the soil and assess the pollution degree; Pollutant type identification: Identify the types of pollutants in the soil; Selection of application methods: According to the soil texture, pollution degree and pollutant types, select appropriate application methods. Specifically, for the remediation of large-area farmland or forest land pollution and the case where the soil texture is relatively uniform, use the strip application method to evenly mix the immobilized microbial particles into the soil. For areas where the pollution point sources are relatively concentrated, select the hole application method to evenly mix the immobilized microbial particles into the soil; For water pollution, the specific implementation is as follows: Loading of special suspension fillers, load the immobilized microbial particles into the suspension fillers according to a certain ratio. After loading is completed, ensure that the immobilized microbial particles are evenly distributed in the suspension fillers; Determination of the placement position, according to the distribution of water pollution and the flow characteristics of the water body, determine the placement position of the immobilized microbial particles. Specifically, put the special suspension fillers into the areas with relatively severe pollution. At the same time, consider the depth and flow rate of the water body to prevent the immobilized microbial particles from being washed away by the water flow or deposited at the bottom of the water.

4. A microbial remediation method according to claim 1, characterized in that: The specific steps of environmental regulation in Step 4 are as follows: Step 41, Establishment of the monitoring system Soil Monitoring: For soil temperature monitoring, select high-precision soil temperature sensors. According to the size of the soil pollution area, bury the sensors in the soil at a depth of 15 - 20 cm in a grid layout, and set up a monitoring point every 5 - 10 square meters; for the pH detection of the soil, the pH sensor uses a corrosion-resistant glass electrode type sensor, and the pH sensor is also buried in the soil according to the above layout method, with a depth of about 10 - 15 cm to ensure that the soil acidity and alkalinity can be accurately reflected; select a dissolved oxygen sensor and install it in a pre-buried air-permeable casing in the soil. The casing ensures good air permeability to accurately measure the dissolved oxygen content in the soil, and the monitoring points are set in the same way as the temperature sensors; use an oxidation-reduction potential sensor to detect the oxidation-reduction state of the soil, and the oxidation-reduction potential sensor is buried in the soil at a depth of 10 - 15 cm, and one is arranged every 3 - 5 meters; Water Body Monitoring: Select waterproof temperature sensors to monitor the water temperature. The waterproof temperature sensors are installed at different water depths. Specifically, a monitoring point is set every 5 - 10 meters to ensure that the temperature changes of different water layers can be monitored; monitor the pH value of the water body. The pH sensor is installed at a position where the water flow in the water body is relatively stable, avoiding installation near the water inlet or outlet, and monitoring points are set at intervals of 5 - 10 meters; monitor the dissolved oxygen in the water body. The dissolved oxygen sensors are installed at different depths and positions in the water body, especially in areas with relatively serious pollution, key arrangements are required, and floating or submersible installation methods are used, and a monitoring point is set every 3 - 5 meters; monitor the oxidation-reduction state of the water body. The oxidation-reduction potential sensor is installed in the water body near the pollution source or areas prone to oxidation-reduction reactions; Step 42: Setting of Environmental Parameter Thresholds: According to the growth and metabolic characteristics of different microbial complex agents, determine the appropriate ranges of temperature, pH value, dissolved oxygen, and oxidation-reduction potential in the soil or water body as thresholds; Step 43: Real-time Monitoring and Data Analysis: The data analysis software analyzes the collected data, compares it with the pre-set thresholds, and judges whether the environmental parameters are within the appropriate range. When a certain parameter exceeds the threshold range, the system automatically issues an alarm signal; Step 44: Implementation of Regulation Measures Temperature Regulation: When the soil temperature is too low, use the method of laying heating wires to heat. According to the soil area and temperature requirements, reasonably arrange the heating wires, and automatically control the heating temperature through a thermostat to gradually raise the soil temperature to the appropriate range; if the soil temperature is too high, use the method of covering with sunshade nets or spraying water to cool down. The shading rate of the sunshade net is selected according to the actual situation, and drip irrigation or sprinkler irrigation is used for spraying water to keep the soil surface moist and reduce the soil temperature; when the water temperature is too low, install a heating rod or use a solar heating system in the water body. When the water temperature is too high, increase the fluidity of the water body. Specifically, turn on the circulation water pump to mix hot water and cold water to reduce the water temperature; pH value regulation: When the soil pH value is too low, lime can be added for adjustment. When the soil pH value is too high, sulfur powder or ferrous sulfate acidic substances can be added. When the water body pH value is too low, sodium hydroxide or sodium carbonate alkaline substances can be added to the water body. When the water body pH value is too high, hydrochloric acid or sulfuric acid acidic substances can be added for neutralization. Dissolved oxygen regulation: When the dissolved oxygen content in the soil is insufficient, a soil ventilation system can be adopted. Specifically, ventilation pipes are buried, and small holes are evenly distributed on the ventilation pipes. Air is introduced into the pipes through a fan, so that the air diffuses into the surrounding soil to increase the dissolved oxygen content in the soil. When the dissolved oxygen content in the water body is insufficient, aeration equipment can be used for oxygenation. Redox potential regulation: If the soil redox potential is too high, reducing substances can be added to the soil. When the soil redox potential is too low, methods such as ventilation or adding oxidizing substances can be used for adjustment. When the water body redox potential is too high, reducing substances such as sodium sulfite or sodium thiosulfate can be added. When the water body redox potential is too low, it can be adjusted by aeration or adding oxidizing substances such as potassium permanganate. Step 45: After the regulation measures are implemented for a preset period of time, the environmental parameters of the soil or water body are monitored and analyzed again to evaluate the regulation effect.

5. A microbial remediation system according to any one of claims 1 - 4, characterized in that: It includes a microbial culture and microbial agent preparation module, a delivery and distribution module, and a monitoring and regulation module. The microbial culture and microbial agent preparation module is equipped with professional microbial culture equipment, which is used for the screening, culture, and propagation of microbial strains. At the same time, the microbial culture and microbial agent preparation module sets up a microbial agent mixing and immobilization production line to achieve the efficient preparation and immobilization treatment of microbial compound agents. For soil remediation, the delivery and distribution module designs an automated soil spraying device, which precisely controls the application amount and application location of immobilized microbial particles according to preset parameters. For water body remediation, the delivery and distribution module sets up an adjustable suspended filler delivery device, which can flexibly adjust the delivery depth and distribution density of suspended fillers according to factors such as water body flow rate and depth. The monitoring and regulation module uses sensor technology to collect real-time data on various environmental parameters and pollutant concentrations in the soil or water body, and transmits the data to the central control system through a wireless transmission module. The central control system analyzes and processes the data based on preset algorithms and models, and automatically controls the regulation equipment.

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