Intelligent response type self-digesting and self-consuming gel biological filler, preparation method thereof, and application of groundwater in-situ remediation equipment

Abstract

The application belongs to the technical field of water treatment, and particularly relates to an intelligent response type self-consuming and self-digesting gel biological filler, a preparation method thereof, and underground water in-situ remediation equipment and application. The filler takes konjac sponge as a skeleton, constructs a gel network with gradually increased cross-linking density from inside to outside in the pores through step-by-step gradient cross-linking of alginate and calcium ions, and co-fixes functional strains, trehalose and oxidation-reduction response type indicators therein. After drying, the volume of the filler is reduced to less than 1 / 3, and the activity is restored after rehydration, so that the filler can be used immediately. During the remediation process, the indicators change color with the metabolic state of the microorganisms, and accordingly, the aeration intensity can be increased to accelerate the in-situ consumption of the filler, without the need of salvage and recovery. The application solves the problems of non-degradability, lack of intelligent monitoring and difficulty in terminal disposal of traditional microbial carriers, and has the functions of efficient degradation, intelligent sensing and green self-consuming.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to an intelligent responsive self-absorbing gel biofiller, its preparation method, and groundwater in-situ remediation equipment and applications. Background Technology

[0002] Leaks and seepage of organic solvents, petrochemical products, and chemical raw materials during production, storage, and transportation can lead to the intrusion of organic pollutants into the groundwater environment. Pollutants such as N,N-dimethylformamide (DMF), toluene, xylene, p-chloroaniline, and petroleum hydrocarbons are chemically stable, highly resistant to biodegradation, and can remain in groundwater for extended periods and spread with water flow. Traditional ex-situ remediation techniques require pumping contaminated groundwater to the surface for treatment. This is not only a massive undertaking with high transportation and disposal costs, but also highly susceptible to leakage and secondary pollution during the pumping and transfer process, making it difficult to meet the needs for efficient remediation of large-area, deep groundwater contaminated sites.

[0003] Against this backdrop, in-situ remediation technology has become a research hotspot in the field of groundwater pollution control due to its advantages such as minimal site disturbance, ease of operation, and relatively controllable cost. Currently, mainstream in-situ remediation technologies are mainly divided into two major directions: chemical remediation and bioremediation. Chemical remediation involves injecting oxidants, reducing agents, and other chemical agents into the contaminated area, achieving rapid degradation of pollutants in a short time. However, its effect is clearly one-off; the remediation effect terminates once the agents are consumed. More importantly, chemical agents may react with minerals and organic matter in groundwater, generating more toxic secondary pollutants and altering the physicochemical properties of groundwater, causing irreversible long-term impacts on the underground ecosystem. In contrast, in-situ bioremediation technology relies on the metabolic activities of functional microorganisms to degrade pollutants, offering significant advantages such as long-lasting effects, low energy consumption, and good environmental compatibility, making it more in line with the concept of green and sustainable governance. However, traditional in-situ bioremediation technologies still face multiple challenges in practical applications.

[0004] First, the colonization and retention of functional strains is the primary bottleneck restricting the efficiency of bioremediation. Due to the lack of effective immobilization carriers, directly added functional strains are easily lost with water flow in the groundwater environment, making it difficult to maintain an effective degradation concentration at the target contamination site. To address this issue, researchers have developed various microbial immobilization technologies. For example, Tianjin University disclosed a method for preparing immobilized slow-release microorganisms for in-situ water remediation in patent document CN111039415A. This method uses molecular sieve particles as the adsorption core to load denitrifying functional bacteria, and then coats them with chitosan to form a slow-release structure, which improves the retention effect of microorganisms to some extent. Chengdu University of Technology disclosed a biomass microsphere in patent document CN115557601A, using porous biochar as a carrier and sodium alginate and CaCl2 as encapsulating agents to embed p-chloroaniline-degrading bacteria in a cross-linked structure, improving the anti-interference ability of the functional bacteria. However, the carrier materials used in the above technologies, molecular sieves and porous biochar, are both non-degradable inorganic or carbonaceous materials, which will remain in the underground environment for a long time after the remediation task is completed. Furthermore, none of these solutions address how to determine whether the packing has completed its repair task or the final disposal of the packing itself. In practical engineering applications, there is still a lack of clear criteria for determining the repair endpoint and for the subsequent treatment of the packing.

[0005] Furthermore, addressing the issue of oxygen deficiency in groundwater leading to suppressed activity of aerobic degrading bacteria, Zhejiang University disclosed a carbon-based adsorption / microbial aerobic degradation risk management composite material in patent document CN118324294A. This material employs a core-shell structure design, with the core consisting of adsorbed biochar, the oxygen-releasing agent calcium peroxide, and the recovery-promoting factor Rpf. The outer shell is a biofilm of petroleum hydrocarbon aerobic degrading bacteria, *Rhodococcus pyridae*, which releases oxygen through calcium peroxide to create a local aerobic habitat for aerobic bacteria in the groundwater environment. This solution effectively improves the petroleum hydrocarbon degradation efficiency through the synergistic effect of the oxygen-releasing agent and Rpf. However, the adsorbed biochar in the core remains non-degradable after long-term operation, and the solution does not involve intelligent monitoring and self-absorption functions of the packing material; the management and control of the remediation process still relies on external monitoring methods.

[0006] Furthermore, researchers have attempted to combine natural polysaccharide materials with alginate cross-linking technology for microbial immobilization. Zhejiang Ocean University disclosed a microbial-supported resin adsorbent for oil spill remediation in patent document CN107837795A. This adsorbent uses konjac glucomannan aerogel particles as a carrier to support petroleum hydrocarbon-degrading bacteria. The microbial support is formed by cross-linking sodium alginate and calcium chloride, and then coated with an acrylate copolymer emulsion and dried. This method is used for the remediation of oil spills. This approach utilizes the porous structure of konjac glucomannan aerogel to support microorganisms and leverages alginate cross-linking to improve the immobilization stability of the microorganisms, thus realizing the application of natural polysaccharide materials in the field of microbial immobilization to a certain extent. However, this approach is mainly designed for surface oil spill remediation scenarios. The outer layer of the acrylate resin used is a non-degradable polymer material, which cannot be naturally absorbed after the remediation task and requires separate recycling and disposal. Meanwhile, existing studies have shown that natural polysaccharide aerogels, represented by konjac glucomannan aerogel, generally have shortcomings such as low mechanical strength and high brittleness, and their structural stability faces challenges when operating under water scouring conditions for a long time.

[0007] Finally, existing bioremediation technologies generally lack intelligent process monitoring and endpoint determination methods at the operation and management level. In practical engineering applications, real-time monitoring of pollutant concentrations in groundwater is limited by sampling cycles and analysis costs, making it difficult to reflect the microbial metabolic state and remediation process within the packing material in a timely manner. When pollutant concentrations drop below standard limits, there is a lack of intuitive and reliable criteria for determining whether the packing material still has degradation capacity, when operation should be terminated, or when the operating strategy should be changed. Existing technologies typically rely on periodic sampling and laboratory testing, which are not only slow to respond but also unable to provide real-time information on the operating status of the packing material itself.

[0008] In summary, existing in-situ groundwater bioremediation technologies still have significant shortcomings in three key aspects: long-term immobilization of functional bacteria, harmless disposal of packing materials, and intelligent monitoring of the operation process. Therefore, developing a novel gel-based biological packing material with efficient immobilization, self-absorption, and environmental responsiveness, along with corresponding intelligent control methods, is of great significance for improving the engineering applicability and environmental friendliness of in-situ groundwater bioremediation technologies. Summary of the Invention

[0009] This invention addresses the problems existing in the prior art by providing an intelligent responsive self-absorbing gel biofiller, its preparation method, and in-situ groundwater remediation equipment and applications. The aim is to overcome the shortcomings of existing microbial immobilization carriers in terms of long-term immobilization capacity, harmless terminal disposal, and intelligent sensing of operational status, thereby achieving green and controllable operation of a highly efficient degradation and remediation system for organic pollutants in groundwater.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] The first aspect of the present invention provides a smart responsive self-absorbing gel biofiller, comprising a matrix framework, a gel network encapsulating the interior and surface of the matrix framework, and functional strains, bioactive protectants and environmentally responsive indicators immobilized in the gel network; The matrix skeleton is konjac sponge; The gel network is formed by cross-linking alginate and divalent metal cations, and the gel network has a gradient structure in which the cross-linking density gradually increases from the inside to the outside within the filler. The environmentally responsive indicator is a redox-responsive indicator, which can generate color or fluorescence signal changes in response to changes in the redox potential inside the filler.

[0012] The filler product of this invention is stored and transported in a dry state, requiring no separate activation treatment before being added to the remediation well. Upon direct placement of the dried filler into the remediation well, it begins to absorb water and swell upon contact with groundwater. The three-dimensional hydrophilic skeleton of the konjac sponge and the hydrophilic groups in the gel network work together to allow water to rapidly penetrate the filler. Within 0.5 to 12 hours, the filler volume gradually recovers to its original size before drying, and its morphology changes from a shrunken, dry state to a full, elastic body.

[0013] Furthermore, the divalent metal cation is calcium ion, and the alginate is sodium alginate.

[0014] The cross-linking of sodium alginate and calcium ions can form a stable gel network. This invention constructs a gel network with cross-linking density gradually increasing from the inside to the outside in the pores of the konjac sponge skeleton. The dense outer cross-linked layer provides the filler with the mechanical strength necessary to resist long-term erosion by groundwater, while effectively preventing the loss of functional strains to the external environment. The loose inner cross-linked layer, on the other hand, retains sufficient space for pollutant mass transfer and microbial metabolic activities, avoiding mass transfer obstruction caused by excessive cross-linking.

[0015] Furthermore, the redox-responsive indicator is one or more of Resazurin, MTT, TTC, and methylene blue.

[0016] This invention immobilizes redox-responsive indicators and functional bacterial strains within a gel network, enabling the packing material itself to sense the metabolic activity of internal microorganisms. During the pollutant degradation phase, the functional strains are metabolically active, maintaining a reducing environment within the packing material. The indicator exists in a reduced state, exhibiting a corresponding color or fluorescent signal. When the pollutant concentration significantly decreases and the available substrate for microorganisms is gradually depleted, the metabolic intensity declines, the redox potential within the packing material rises, and the indicator signal undergoes a detectable change. This signal transition is directly correlated with the operating state of the packing material, providing an intuitive and scientific basis for determining the remediation endpoint and dynamically adjusting operating strategies.

[0017] Furthermore, the functional strain is a microorganism capable of degrading one or more of the following organic pollutants: N,N-dimethylformamide (DMF), toluene, xylene, benzene, ethylbenzene, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, petroleum hydrocarbons, methyl tert-butyl ether (MTBE), and nitro aromatic hydrocarbons.

[0018] Furthermore, the functional strain is selected from one or more of the following genera: Paracoccus ( Paracoccus ), Pseudomonas spp. Pseudomonas ), Rhodococcus spp. ( Rhodococcus Acinetobacter spp. Acinetobacter ), Bacillus spp. ( Bacillus ), Dehalogenated Pseudomonas ( Dehalococcoides ).

[0019] Further, preferably, the functional strain is selected from one or more of the following species: *Paracoccus sulfooxidans* (… Paracoccus sulfuroxidans ), denitrifying paracocci ( Paracoccus denitrificans ), Paracoccus variegata ( Paracoccus versutus ); Pseudomonas aeruginosa ( Pseudomonas aeruginosa ); Rhodococcus ( Rhodococcus ruber ), Pyridine-loving Rhodococcus ( Rhodococcus pyridinivorans Acinetobacter baumannii (); Acinetobacter baumannii Acinetobacter johnsonii ( ) Acinetobacter johnsonii ); Bacillus pumilus ( Bacillus pumilus ); and dehalogenated cactus ( Dehalococcoides mccartyi ).

[0020] Furthermore, the bioactive protective agent is trehalose.

[0021] Trehalose, as a bioactive preservative, is a core component that enables the bacterial strains to maintain their activity even after the packing material has been stored in a dry state. A major problem faced during the drying process is that moisture removal leads to the loss of the hydration layer around the cell membranes and proteins of functional bacterial strains, subsequently causing protein denaturation, membrane structure damage, and cell death. The hydroxyl groups on trehalose molecules can form hydrogen bonds with polar groups on the surface of phospholipids and proteins in the bacterial cell membrane, replacing the hydrogen bond sites originally occupied by water molecules, thus maintaining the natural conformation of biomolecules in a dehydrated state. Furthermore, trehalose can form an amorphous glass matrix during drying, encapsulating the bacterial cells, restricting molecular movement and chemical reaction rates, and preventing cell structure collapse and damage during storage. The addition of trehalose allows functional bacterial strains to maintain high metabolic activity after drying, storage, and rehydration, fundamentally ensuring the engineering feasibility of using the packing material immediately upon application.

[0022] The second aspect of this invention provides a method for preparing the above-mentioned intelligent responsive self-absorbing gel biofiller, comprising the following steps: (1) Soak the konjac sponge in clean water, take it out and dry it to constant weight; immerse the dried konjac sponge in a solution containing divalent metal cations, soak it, take it out and remove the excess solution from the surface and inside, so that the wet weight of the konjac sponge is controlled at 2 to 4 times the weight in the dry state, and obtain the pretreated matrix. (2) Immerse the pretreated matrix in a mixed solution containing functional strains, alginate, bioactive protectant and redox-responsive indicator; (3) Take out the filler after soaking in step (2) and immerse it in a solution containing divalent metal cations for soaking; the concentration of the solution containing divalent metal cations in step (3) is greater than the concentration of the solution containing divalent metal cations in step (1); (4) Take out the filler after soaking in step (3), soak it in clean water to remove unreacted components, and obtain wet filler; (5) Dry the wet packing material to reduce the moisture content of the packing material to 5%~10% to obtain the intelligent responsive self-absorbing gel biological packing material.

[0023] Further, in step (1), the mass concentration of the solution containing divalent metal cations is 0.5% to 2.5%, and the konjac sponge is soaked in the solution containing divalent metal cations for 10 to 20 minutes.

[0024] Furthermore, the solution containing divalent metal cations is a CaCl2 solution.

[0025] Furthermore, the soaking time in step (2) is 10 to 30 minutes.

[0026] Furthermore, the concentration of the functional strain in the mixed solution described in step (2) is 2.0 × 10⁻⁶. 8 ~8.0×10 8 CFU·mL -1 The mass concentration of alginate is 1%~4%, the mass concentration of bioactive protective agent is 1%~4%, and the mass concentration of redox-responsive indicator is 0.01%~0.5%.

[0027] Furthermore, the concentration of the functional strain in the mixed solution described in step (2) is 5.0 × 10⁻⁶. 8 ~7.0×10 8 CFU·mL -1 The mass concentration of alginate is 1.5%~3%, the mass concentration of bioactive protective agent is 1.5%~3%, and the mass concentration of redox-responsive indicator is 0.05%~0.2%.

[0028] When the indicator concentration is too low, the intensity of the color or fluorescence signal generated by reduction is insufficient, making it difficult to reliably observe in actual groundwater remediation scenarios; conversely, excessively high indicator concentrations may adversely affect the metabolic activity of the strains. Considering the requirement in this invention that the indicator maintains a stable response during long-term operation of the packing material, the concentration range is set to 0.01%–0.5%, preferably 0.05%–0.2%. This range ensures sufficient observability of the indicator response signal while avoiding potential interference with the activity of functional strains.

[0029] Further, in step (3), the mass concentration of the solution containing divalent metal cations is 2.5% to 5.0%, and the soaking time is 5 to 15 min.

[0030] The calcium ion concentration plays different roles in the two-step process. In step (1), a low concentration (0.5%~2.5%) is used to pretreat the konjac sponge to allow the sponge to uniformly adsorb Ca inside. 2+ As an ion source for subsequent in-situ crosslinking, a concentration that is too low will lead to Ca... 2+ Insufficient reserves, inadequate cross-linking, and excessively high concentrations will prematurely form a dense gel layer on the sponge surface, hindering the inward penetration of the mixed solution in step (2). Step (3) uses a high concentration (2.5%~5.0%) for surface-strengthening cross-linking, utilizing the concentration gradient diffusion of calcium ions from the outside to the inside to form a gel layer with higher cross-linking density and a denser structure on the filler surface, thereby constructing a gradient structure of "dense on the outside and sparse on the inside". However, the calcium ion concentration should not be too high, otherwise the surface gel will become brittle due to excessive cross-linking. Through stepwise gradient cross-linking, the calcium ion concentration and sodium alginate concentration work together to achieve a differentiated gel network on the konjac sponge skeleton with the cross-linking density gradually increasing from the inside to the outside.

[0031] Furthermore, the soaking time in the clean water in step (4) is 10~14 h.

[0032] Furthermore, the drying temperature in step (5) is 30~60℃, and the drying time is 5~12 h.

[0033] Furthermore, the drying temperature in step (5) is 35~45℃.

[0034] Furthermore, after drying in step (5), the volume of the filler is reduced to less than 1 / 3 of that before drying, and the weight is reduced by more than 90%.

[0035] In existing technologies, natural polysaccharide porous materials, such as konjac glucomannan aerogel, generally face severe volume shrinkage and structural embrittlement problems during drying. The root cause lies in the immense capillary force generated by the nanoscale pore structure of the aerogel during water evaporation. Combined with the insufficient rigidity of the aerogel skeleton itself, this leads to irreversible collapse and fracture of the pore walls under drying stress, ultimately forming a brittle mass. In this invention, the konjac sponge itself possesses micron-level interconnected pores and excellent compression resilience. Its skeleton can withstand capillary stress during drying without structural collapse. The calcium alginate gel network forms an embedded, interpenetrating network structure within the pores of the konjac sponge. During drying, both shrink synergistically; the elastic support of the sponge skeleton prevents cracking and detachment during gel shrinkage, while the filling of the gel network enhances the density of the sponge skeleton. The filler pore walls of this invention shrink and become dense after drying, but the overall structure remains intact without brittle fracture, and it can quickly recover its original shape after rehydration. After drying, the packing material shrinks significantly in volume, reduces weight substantially, and increases hardness, resulting in a substantial decrease in the cost of storing and transporting the packing material.

[0036] A third aspect of the present invention provides groundwater in-situ remediation equipment, including a remediation well system, an aeration system, and an intelligent responsive self-absorbing gel biological filler filled in the remediation well system; The repair well system includes multiple repair wells arranged according to the direction of groundwater flow; The aeration system includes an aeration blower, an aeration pipe, and an aeration head installed at the bottom of the repair well for supplying air to the repair well. The aeration pipe connects the aeration blower to the aeration head at the bottom of each repair well.

[0037] Furthermore, the diameter of the repair well is 100-250 mm, the depth is 6-8 m, and the distance between adjacent repair wells is 1-3 m.

[0038] Furthermore, the filling amount of the intelligent responsive self-absorbing gel biofiller is 2% to 15% of the effective volume of the repair well.

[0039] Furthermore, when the concentration of pollutants in the groundwater exceeds the standard limit but is within 10 times the limit, the filling amount of the filler is 2% to 8% of the effective volume of the remediation well; when the concentration of pollutants in the groundwater exceeds the standard limit by more than 10 times, the filling amount of the filler is 9% to 15% of the effective volume of the remediation well.

[0040] A fourth aspect of this invention provides a method for in-situ remediation of groundwater, comprising the following steps: (1) In the polluted area, one or more remediation wells are set up according to the groundwater flow direction, the intelligent responsive self-absorbing gel biological filler described in this invention is filled into the remediation wells, and an aeration system for supplying air to the remediation wells is set up. (2) The aeration system continuously supplies air to the repair well to maintain the initial aeration intensity, so that the functional strains in the packing can degrade organic pollutants in the groundwater. (3) Monitor the color or fluorescence signal change of the environmental responsive indicator in the packing, and judge the operating status of the packing based on the signal change; when the signal change of the environmental responsive indicator indicates that the packing has entered the disposal stage from the pollutant degradation stage, increase the aeration intensity of the aeration system to 1.5 to 3 times the initial aeration intensity to accelerate the biodegradation of the packing and make the packing disposed of in situ in the repair well.

[0041] Furthermore, the initial aeration intensity mentioned in step (2) is 1.0~5.0 m. 3 ·(m 2 ·h) -1 .

[0042] Furthermore, in step (2), the aeration system supplies the corresponding gas to the repair well according to the metabolic type of the functional strain; when the functional strain is an aerobic or facultative anaerobic bacterium, the supplied gas is air or oxygen; when the functional strain is an anaerobic bacterium, the supplied gas is an oxygen-free gas.

[0043] Furthermore, in step (3), when the color or fluorescence signal of the environmentally responsive indicator changes from a reduced state characteristic signal to an oxidized state characteristic signal, it is determined that the filler has entered the disposal stage from the pollutant degradation stage. For example, when the environmentally responsive indicator is resazurin, the reduced state characteristic signal is pink or strong fluorescence, and the oxidized state characteristic signal is blue or weak fluorescence.

[0044] In constructing the repair system, the dry filler material is placed into the repair well. Upon contact with groundwater, it begins to absorb water and expand. The synergistic effect of the three-dimensional hydrophilic skeleton of the konjac sponge and the gel network allows water to penetrate rapidly, and the trehalose dissolves accordingly. The functional strains recover their metabolic activity within a few hours after rehydration, and the filler material recovers from a dry, shrunken state to an elastic, saturated state. It can be put into use without on-site activation.

[0045] After the repair operation is initiated, the aeration system continuously supplies air at its initial intensity. The airflow generated by aeration carries groundwater through the pores of the packing material, ensuring full contact between dissolved pollutants and the microorganisms. At this time, microbial metabolism is vigorous, and the internal redox potential of the packing material remains low. The co-immobilized redox-sensitive indicators are driven by intracellular reducing forces to be converted into a reduced state, exhibiting characteristic signals of the reduced state, which directly reflect that the packing material is in an active degradation state.

[0046] As pollutant concentration decreases, microbial metabolic intensity declines, and the redox potential inside the packing material rises accordingly. Redox-sensitive indicators then transition from a reduced state to an oxidized state. This signal shift indicates that the packing material has moved from the degradation stage to the absorption stage. At this point, increasing the aeration intensity to 1.5 to 3 times the initial value enhances hydraulic shear, causing partially disintegrated gel fragments and sponge skeletons to detach from the packing material, accelerating its physical disintegration. Sufficient dissolved oxygen supply significantly increases the metabolic activity of aerobic microorganisms within the packing material, leading to increased secretion and catalytic efficiency of glucomannanase and alginate lyase, resulting in an exponential increase in the biodegradation rate.

[0047] The ability of the packing material to be in-situ absorbed within the well is fundamentally due to the biodegradability of both the konjac sponge and the calcium alginate gel network. The konjac glucomannan backbone is composed of glucose and mannose linked by β-1,4 and β-1,3 glycosidic bonds. These glycosidic bonds can be hydrolyzed and broken by glucomannanases secreted by microorganisms, gradually degrading the polysaccharide backbone into low-molecular-weight oligosaccharides and even monosaccharides. The degradation of the calcium alginate gel relies on two pathways: ion exchange and enzymatic depolymerization. Calcium ions in the cross-linked network can exchange with monovalent cations such as sodium and potassium in groundwater, gradually replacing the cross-linking sites and causing the gel network to dissolve and dissociate into soluble sodium alginate fragments. Simultaneously, alginate lyases secreted by microorganisms can cleave the glycosidic bonds of sodium alginate through a β-elimination mechanism, further accelerating gel depolymerization. Through the synergistic effect of physical disintegration and biodegradation, the packing material disintegrates and disperses layer by layer from the outside in, ultimately being completely absorbed within the well without the need for retrieval or recovery.

[0048] When multiple wells are used in conjunction, the well group deployed along the groundwater flow direction forms a continuous reaction barrier. The indicator signals in each well independently reflect the operating status, and the aeration intensity can be adjusted separately. The remediation wells that have completed the treatment can be restored to function simply by adding dry packing material, realizing the entire cycle of operation from pollution degradation to packing material treatment and then to functional regeneration.

[0049] Compared with the prior art, the present invention has the following beneficial effects: (1) The filler material forms a differentiated structure with a dense outer layer and a loose inner layer through the stepwise gradient cross-linking of the elastic skeleton of konjac sponge and calcium alginate gel. The dense outer layer provides the filler material with mechanical strength to resist groundwater erosion and effectively reduces the loss of functional strains; the loose inner layer retains sufficient space for pollutant mass transfer and microbial metabolism. During the drying process, both shrink synergistically, the filler material volume is greatly reduced and the hardness is increased but there is no brittleness, which facilitates storage and transportation; after rehydration, it expands and recovers rapidly, realizing immediate use.

[0050] (2) For the first time, redox-responsive indicators and functional strains were co-immobilized in a gel network, enabling the packing material itself to sense the metabolic activity of internal microorganisms. During the degradation stage, the indicator exhibits a reduced state characteristic signal; after the pollutants are depleted, the signal undergoes a visually discernible change, providing an intuitive basis for judging the remediation endpoint and adjusting the operational strategy, thus changing the passive mode of traditional remediation that relies on external sampling and monitoring.

[0051] (3) The packing material is composed of natural biodegradable materials such as konjac sponge and calcium alginate gel. After the repair task is completed, the biodegradation of the packing material in the well can be accelerated by increasing the aeration intensity, so as to achieve in-situ self-disposal without the need for retrieval and recycling, thus avoiding the risk of secondary pollution caused by the long-term residue of traditional non-degradable carriers from the source.

[0052] (4) This invention constructs a degradation system covering multiple genera and species of bacteria, which can remediate various typical organic pollutants in groundwater such as DMF, benzene series compounds, chlorinated hydrocarbons, and polycyclic aromatic hydrocarbons, and has a wide range of applications. At the same time, through the matching design of the filler dosage and pollution load, as well as the multi-well combined and independently controlled operation mode, the engineering applicability and economy of the remediation system are improved. Attached Figure Description

[0053] Figure 1 The macroscopic morphology of the gel biofiller prepared in Example 1 is compared under wet and dry conditions.

[0054] Figure 2Figure 1 shows the physicochemical properties of the gel biofiller prepared in Example 1. In the figure, a1 is a macroscopic photograph of the gel biofiller in a moist state; a2 is a low-magnification scanning electron microscope (SEM) image of the gel biofiller (scale bar 200 μm); a3 is a high-magnification scanning electron microscope (SEM) image of the gel biofiller (scale bar 1 μm); a4 is a cross-sectional SEM image of the gel biofiller and the EDS surface distribution of C, O, and Ca elements; b is a comparison of the compressive stress-strain curves of konjac sponge and gel biofiller; c is a bar chart comparing the ATPase activities of free bacteria and fixed bacteria in the gel biofiller; d is the effect of the gel biofiller on COD and NH4+. + -N,PO4 3- -P transmission rate comparison bar chart.

[0055] Figure 3 The effects of different drying temperatures on the physicochemical properties of gel biofillers in Examples 1-5 are characterized. Figure a shows the microstructure (SEM) of the filler at different drying temperatures; b and c show the changes in moisture content of the filler over time at different drying temperatures; d shows the weight changes of the filler dried at different temperatures under three water absorption-desorption cycles; e shows the comparison of swelling ratios of the filler dried at different temperatures under three water absorption-desorption cycles; f and g show the changes in the activity of microbial ATPase in the filler under different drying conditions; h shows the transmission electron microscopy (TEM) images of microorganisms in the filler after drying at different temperatures; i and j show the changes in compressive stress of the filler under different drying conditions; k shows the Fourier transform infrared (FTIR) curves of the filler treated at different drying temperatures; and l shows the differential scanning calorimetry (DSC) curves of the filler treated at different drying temperatures.

[0056] Figure 4 Figures show the long-term operational stability of the gel biofillers treated at different drying temperatures in Examples 1-5. In the figures, a) is a comparison of the macroscopic morphology of the gel biofillers treated at different drying temperatures during operation in the simulated remediation system for 0 days, 20 days, and 40 days; b) is the pH change curve of the system during 50 days of operation; c) is the OD value of the system during 50 days of operation. 600 The curves showing the changes in values ​​are as follows: d is the curve showing the change in COD concentration of the packing material treated at different drying temperatures during 50 days of operation; e is the curve showing the change in DMF concentration of the packing material treated at different drying temperatures during 50 days of operation; f is the curve showing the change in NH4+ concentration of the packing material treated at different drying temperatures during 50 days of operation. + -N concentration change curve; g is the TP concentration change curve of the packing material treated at different drying temperatures during 50 days of operation.

[0057] Figure 5The bar chart shows the structural stability comparison of the packing materials in Example 1 and Comparative Example 1.

[0058] Figure 6 The mechanical properties of the packings in Example 1 and Comparative Example 2 are compared; in the figure, a is the compressive stress-strain curve and b is the deformation recovery rate bar chart.

[0059] Figure 7 The figures show a comparison of the retention performance and mass transfer performance of the strains in the packing material of Example 1, Comparative Example 3, and Comparative Example 4; in the figure, a is the curve of strain loss rate changing over time, b is the curve of OD600 changing, and c is the curve of mass transfer rate changing.

[0060] Figure 8 This is a comparison of the storage stability of the packing materials in Example 1, Comparative Example 6, and Comparative Example 7; Figure a shows the change curve of the bacterial activity retention rate during storage, and figure b shows the change curve of the pollutant degradation rate after rehydration for 48 hours after storage.

[0061] Figure 9 The figures show the pollutant degradation kinetic curves of the packing materials in Examples 1, 6-11, and Comparative Examples 1-7; a1 represents the sample from the examples, and a2 represents the sample from the comparative examples.

[0062] Figure 10 The figures show the kinetic curves of strain activity recovery for the packing materials used in Examples 1, 6-11, and Comparative Examples 1-7; in the figures, a1 represents the sample from the examples, and a2 represents the sample from the comparative examples.

[0063] Figure 11 The figure shows a comparison of three-dimensional fluorescence spectra (EEM) of the effluent from the simulated polluted groundwater after treatment of the blank control group, Example 1, Comparative Example 1, and Comparative Example 6; in the figure, a is Comparative Example 6, b is the blank control group, c is Comparative Example 1, and d is Example 1.

[0064] Figure 12 This is a schematic diagram of the well repair device of the present invention; in the figure: 1-repair well, 2-intelligent responsive self-absorbing gel biological packing, 3-aeration head, 4-aeration blower, 5-aeration pipe. Detailed Implementation

[0065] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention. It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application.

[0066] Example 1 This embodiment provides a smart responsive self-absorbing gel biofiller, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 15 min, then take it out and dry it at 105℃ to constant weight. Immerse the dried konjac sponge in a 2% CaCl2 solution for 15 min, then take it out and squeeze out the excess CaCl2 solution on the surface and inside, so that the wet weight of the konjac sponge is controlled to be 3 times the weight in the dry state, and the pretreated matrix is ​​obtained.

[0067] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 15 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* (…). Paracoccus sulfuroxidans The strain 175A1-1 is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 23659 (see Chinese invention patent CN114456974A, "A strain of sulfur-oxidizing paracoccus that can efficiently degrade DMF and its application in the treatment of DMF-containing wastewater"). The strain concentration is 6.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 2%; the mass concentration of trehalose was 2%; and the mass concentration of resazurin was 0.1%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+ An in-situ cross-linking reaction occurs, forming a gel network containing functional strains, trehalose, and resazurite within the pores and on the surface of the konjac sponge.

[0068] (3) Take out the filler after step (2) and immerse it in a CaCl2 solution with a mass concentration of 4% for 10 minutes to perform surface strengthening crosslinking. A gel layer with higher crosslinking density is formed on the surface of the filler, thereby constructing a gradient gel structure with crosslinking density gradually increasing from the inside to the outside.

[0069] (4) Take out the packing material after step (3) and soak it in clean water for 12 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0070] (5) The wet packing obtained in step (4) is dried at 40°C for 11 h to reduce the moisture content of the packing to 6%. The volume of the dried packing is reduced to about 1 / 4 of that before drying, the weight is reduced by about 92%, and the hardness is significantly improved, thus obtaining the dry intelligent responsive self-absorbing gel biological packing.

[0071] Figure 1These are macroscopic morphological photographs of the gel biofiller prepared in this embodiment under wet (left) and dry (right) conditions. As can be seen from the figures: in the wet state, the filler is a translucent milky-white gel with a complete structure and uniform texture; after drying, the filler shrinks as a whole, turns light yellow, but still maintains its blocky shape without cracking or powdering. This indicates that the gel biofiller has good structural stability and can maintain its carrier morphology under alternating wet and dry conditions, making it suitable for practical engineering applications.

[0072] Figure 2 The physicochemical properties of the gel biofiller prepared in this embodiment were characterized, wherein: a1 is a macroscopic photograph of the gel bio-carrier in a moist state, showing that the carrier is a molded block with a size of approximately 1.5 cm × 1.5 cm × 1.5 cm, with an intact structure and good moldability; a2 is a low-magnification scanning electron microscope (SEM) image (scale bar 200 μm) of the gel biological filler, which shows that the filler has a three-dimensional interconnected porous network structure with good pore connectivity. a3 is a high-magnification scanning electron microscope (SEM) image of the gel biological filler (scale bar 1 μm), which shows that the surface of the filler is loaded with a large number of morphologically intact microbial cells that are firmly attached. a4 shows the cross-sectional SEM image of the gel biofiller and the EDS surface distribution diagram of C, O, and Ca elements, which shows that C, O, and Ca elements are uniformly distributed in the filler, proving that the gel cross-linking reaction is sufficient and the structure is uniform and stable. b is a comparison of the compressive stress-strain curves of konjac sponge and gel biofiller. It can be seen that the compressive strength of gel biofiller is significantly higher than that of pure konjac sponge, and its mechanical properties are greatly improved. c is a bar chart comparing the ATPase activities of free bacteria and bacteria fixed in gel biofiller, showing that the immobilized microorganisms still maintain high metabolic activity and the carrier has good biocompatibility; d represents the effect of gel biological filler on COD and ammonia nitrogen (NH4) + -N), phosphate (PO4) 3- The bar chart comparing the transport rates of COD and PO4 shows that the packing material has the highest transport rate for COD, followed by PO4. 3- -P has the lowest transport rate, proving that the gel biofiller of the present invention has good mass transfer capability.

[0073] Example 2 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Embodiment 1 only in step (5) by freeze-drying the wet filler at -50°C for 40 h to obtain the dry smart responsive self-absorbing gel biofiller.

[0074] Example 3 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Embodiment 1 only in step (5) by drying the wet filler at 23°C for 70 h to obtain the dry smart responsive self-absorbing gel biofiller.

[0075] Example 4 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Embodiment 1 only in step (5) by drying the wet filler at 50°C for 8 hours to obtain the dry smart responsive self-absorbing gel biofiller.

[0076] Example 5 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Embodiment 1 only in step (5) by drying the wet filler at 60°C for 6 h to obtain the dry smart responsive self-absorbing gel biofiller.

[0077] To verify the effects of different drying temperatures and corresponding drying times on the physicochemical properties and long-term operational stability of the intelligent responsive self-absorbing gel bio-filler of this invention, the fillers prepared in Examples 1-5 were characterized, and the results are as follows: Figure 3 and Figure 4 As shown.

[0078] Figure 3 The effects of different drying temperatures on the physicochemical properties of gel biofillers in Examples 1-5 were characterized. The core variable was the drying temperature (-50℃, 23℃, 40℃, 50℃, 60℃). The rest of the preparation steps were completely the same, only the drying conditions were changed to verify the effect of temperature on the performance of the filler.

[0079] Figure 3 In the figure, 'a' shows the microstructure (SEM) images of the packing material at different drying temperatures. It can be seen that freeze-drying at -50℃ preserves the complete three-dimensional porous structure with clear and well-connected pores. Drying at 23℃ causes slight shrinkage of the pores, but the porous structure is still observable. Drying at 40℃ / 50℃ / 60℃ shows that the pores gradually collapse and shrink with increasing temperature, reaching a dense structure at 60℃ with almost no visible pores. This demonstrates that the higher the temperature, the more significant the shrinkage of the packing material's porous structure, and freeze-drying (-50℃) best preserves the original porous structure.

[0080] Figures b and c show the changes in the moisture content of the filler over time at different drying temperatures (40℃ / 50℃ / 60℃ / 23℃). It can be seen that the higher the temperature, the faster the moisture content decreases: at 50℃ and 60℃, the moisture content decreases rapidly and then rebounds, possibly due to surface drying followed by internal moisture migration; the drying curve at 40℃ is flat, with a uniform decrease in moisture content, eventually stabilizing at a low level. The drying process at 23℃ is slow, with the moisture content gradually decreasing, reaching its lowest point around 70 hours, and then rebounding due to ambient humidity.

[0081] Figure d shows the weight change curves of the packing material dried at different temperatures under three water absorption-desorption cycles. It can be seen that the water absorption kinetics and saturated weight of the packing material treated at different drying temperatures differ significantly: the -50℃ freeze-drying group has a fast water absorption rate, high saturated weight, and the best cycle stability; the 60℃ group has high water absorption performance in the first cycle, but subsequent degradation is significant; the 23℃ group consistently has the lowest water absorption rate and saturated weight; the 40℃ group has moderate water absorption performance and good cycle stability, achieving a balance between water absorption capacity and structural stability.

[0082] e is a bar chart comparing the swelling rates of the packing material dried at different temperatures under three water absorption-desorption cycles. It can be seen that the -50℃ group consistently exhibits the highest swelling rate and best stability throughout the three cycles; the 60℃ group has a relatively high swelling rate in the first cycle, but subsequent cycles show significant attenuation; the 23℃ group consistently has the lowest swelling rate with a large attenuation; and the 40℃ group has a moderate swelling rate and good cyclic stability, balancing swelling performance and structural stability.

[0083] Figures f and g show the changes in microbial ATPase activity in the packing material under different drying conditions. Figure f shows that during the drying process at 40℃, the microbial ATPase activity decreased slowly and remained at a high level after 11 hours; while the activity in the 50℃ and 60℃ groups decreased rapidly with prolonged drying time, with the 60℃ group showing particularly severe activity loss. Figure g further compares the enzyme activity after drying at different temperatures. The 23℃ and 40℃ groups showed the highest and most stable activity, the -50℃ freeze-drying group had the lowest activity, followed by the 50℃ group, and the 60℃ group consistently maintained the lowest activity. This indicates that the drying processes at 23℃ and 40℃ have the least impact on microbial activity and are more conducive to maintaining the biological functional stability of the packing material.

[0084] h shows transmission electron microscopy (TEM) images of microorganisms in the packing material after drying at different temperatures. A TEM observation was added for drying at 30℃. It can be seen that under drying conditions of 30℃ and 40℃, the microbial cells have intact morphology and clear structure; under drying conditions of 50℃, the cells show slight deformation; under drying conditions of 60℃, the cells are obviously swollen and ruptured, and the internal structure is destroyed.

[0085] Figures i and j show the compressive stress variation curves of the packing material under different drying conditions. Figure i shows that during the drying process at 40℃, the compressive strength of the packing material increases slowly with time, reaching a stable value after 11 hours; while the strength of the 50℃ and 60℃ groups increases rapidly with drying time, with the 60℃ group reaching a relatively high strength within 5 hours. Figure j compares the mechanical properties of each treatment group during the rehydration process after drying at different temperatures. It is found that the compressive stress of each group decreases significantly after water absorption and tends to be similar, indicating that rehydration can restore the flexibility of the material to a certain extent. The initial strength of the 50℃ and 40℃ groups is higher, while the strength of the -50℃, 23℃, and 60℃ groups is lower. In summary, the 40℃ drying process can enable the packing material to obtain moderate and stable mechanical strength, taking into account both structural stability and toughness.

[0086] Figures k and l show the Fourier Transform Infrared (FTIR) and Differential Scanning Calorimetry (DSC) curves of the filler material treated at different drying temperatures, respectively. Figure k shows that the characteristic absorption peak positions and intensities of each temperature group are basically consistent, indicating that the drying temperature did not change the chemical composition and functional group structure of the filler material. Figure l shows that the thermal decomposition temperatures of the filler material dried at different temperatures did not differ significantly, and all maintained good thermal stability. This indicates that the chemical structure and thermal stability of the filler material were not damaged under different drying conditions, and the material properties remained stable.

[0087] Figure 4 The images show the structural and functional stability of the gel bio-fillers treated at different drying temperatures (-50℃, 23℃, 40℃, 50℃, 60℃) in Examples 1-5, after continuous operation for 50 days in a simulated groundwater remediation system (shaking table, 40 rpm, 10℃). The core purpose is to verify the morphological integrity, microbial activity, and pollutant removal efficiency of the fillers prepared under different drying conditions in long-term practical applications.

[0088] Figure 4 In the image, 'a' represents macroscopic morphology comparisons of gel biofillers treated at different drying temperatures during operation in the simulated remediation system for 0, 20, and 40 days. It can be seen that in the initial stage (0 days), the filler in the -50℃ freeze-dried group had the largest size and lightest color, while the filler in the 23℃ and above temperature groups shrank and darkened in color. After 20 days, all filler groups absorbed water and recovered to a semi-transparent gel state, with a basically intact morphology. After 40 days, the filler in the -50℃, 50℃, and 60℃ groups showed significant fragmentation, swelling, and loss, while the filler in the 23℃ and 40℃ groups still maintained a relatively good blocky morphology. This indicates that the filler treated at mild temperatures possesses both water absorption and recovery capabilities and long-term structural stability, making it more suitable for long-term operation.

[0089] b shows the pH change curves of the system during 50 days of operation for the packing materials treated at different drying temperatures. It can be seen that the pH of each group fluctuated within the suitable range of 6.0 to 8.0 for microorganisms, and stabilized between 7.5 and 8.0 in the later stage of operation. The fluctuation range was small, indicating that the packing materials after different treatments could maintain a relatively stable reaction environment over a long period of time and had good buffering capacity.

[0090] c represents the system OD during 50 days of operation of packing materials treated at different drying temperatures. 600 The curves showing the change in values ​​indicate that the overall concentration remained at a low level (all below 0.4), with only brief increases at individual time points. This suggests that the overall concentration of free bacteria in the liquid phase was limited, and the immobilized microorganisms remained mainly inside the carrier without large-scale detachment.

[0091] Figure d shows the COD concentration changes of the packing material treated at different drying temperatures during 50 days of operation. It can be seen that the COD concentration of each group peaked around days 10-15, then rapidly decreased and stabilized at a low level. This indicates that a certain amount of soluble organic matter was released in the early stages of packing material operation, possibly originating from soluble components in the carrier, extracellular substances released by microorganisms under stress, and the temporary accumulation of DMF degradation intermediates. As the system gradually stabilized, these organic substances were further transformed or removed, thus the COD decreased rapidly and tended to stabilize. This result shows that the release of organic matter in the initial stage did not have a sustained adverse effect on the subsequent operation of the system.

[0092] e shows the DMF concentration variation curves of the packing material treated at different drying temperatures during 50 days of operation. It can be seen that the DMF concentrations in the 40℃, 50℃, and 23℃ groups decreased rapidly and remained stable at extremely low levels for a long period, with the 40℃ group showing the most stable removal efficiency. In contrast, the DMF concentration in the -50℃ group remained consistently high and fluctuated significantly, while the removal efficiency in the 60℃ group was also significantly lower. This indicates that the packing material dried at 40℃ exhibits the best removal performance for the characteristic organic pollutant DMF.

[0093] f represents the NH4 content of packing materials treated at different drying temperatures during 50 days of operation. + The curves showing the changes in ammonia nitrogen concentration show that the concentrations in each group fluctuated slightly within the range of 35–45 mg / L. The concentration in the 40℃ group was the most stable, with no significant fluctuations, indicating that the activity of the nitrifying microorganisms was stable and the nitrogen cycle system was functioning well.

[0094] g represents the TP concentration variation curves of the packing material treated at different drying temperatures during 50 days of operation. It can be seen that the total phosphorus concentration in each group remained stable at a low level of 1.0–2.0 mg / L, with no significant differences, indicating that different drying temperatures have little impact on the phosphorus removal performance of the packing material, and each group was able to maintain a stable phosphorus concentration in the system.

[0095] Example 6 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Embodiment 1 only in that: the functional strain in the mixed solution in step (2) is replaced by *Pseudomonas aeruginosa* instead of *Paragonimococcus sulfooxidans*. Pseudomonas aeruginosa S2, deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 3034 (see Chinese Invention Patent CN102250790A, "A Highly Efficient Biosurfactant-Producing Bacterium S2 and Its Fermentation Culture Medium"), has a strain concentration of 6.0 × 10⁻⁶. 8 CFU·mL -1 The remaining preparation steps, raw materials, and parameters are the same as in Example 1.

[0096] Example 7 This embodiment provides a smart responsive self-absorbing gel biofiller, which differs from Example 1 only in that the redox-responsive indicator in the mixed solution in step (2) is replaced by thiazolyl blue (MTT) with a mass concentration of 0.1%. The remaining preparation steps, raw materials and parameters are the same as in Example 1.

[0097] Example 8 This embodiment provides a smart responsive self-absorbing gel biofiller, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 15 min, then take it out and dry it at 105℃ to constant weight. Immerse the dried konjac sponge in a 2% CaCl2 solution for 15 min, then take it out and squeeze out the excess CaCl2 solution on the surface and inside, so that the wet weight of the konjac sponge is controlled to be 3 times the weight in the dry state, and the pretreated matrix is ​​obtained.

[0098] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 15 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a strain concentration of 8.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 4%; the mass concentration of trehalose was 1.5%; and the mass concentration of resazurin was 0.3%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+An in-situ cross-linking reaction occurs, forming a gel network containing functional strains, trehalose, and resazurite within the pores and on the surface of the konjac sponge.

[0099] (3) Take out the filler after step (2) and immerse it in a CaCl2 solution with a mass concentration of 4% for 10 minutes to perform surface strengthening crosslinking. A gel layer with higher crosslinking density is formed on the surface of the filler, thereby constructing a gradient gel structure with crosslinking density gradually increasing from the inside to the outside.

[0100] (4) Take out the packing material after step (3) and soak it in clean water for 12 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0101] (5) The wet packing obtained in step (4) is dried at 40°C for 11 h to reduce the moisture content of the packing to 6%. The volume of the dried packing is reduced to about 1 / 4 of that before drying, and the weight is reduced by about 92%, thus obtaining the dry intelligent responsive self-absorbing gel biological packing.

[0102] Example 9 This embodiment provides a smart responsive self-absorbing gel biofiller, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 15 min, then dry it at 105℃ to constant weight. Immerse the dried konjac sponge in a 1% CaCl2 solution for 20 min, then remove it and squeeze out the excess CaCl2 solution from the surface and inside, so that the wet weight of the konjac sponge is controlled to be 2.5 times the weight in the dry state, and the pretreated matrix is ​​obtained.

[0103] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 20 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a strain concentration of 4.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 2.5%; the mass concentration of trehalose was 3%; and the mass concentration of resazurin was 0.08%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+ An in-situ cross-linking reaction occurs, forming a gel network containing functional strains, trehalose, and resazurite within the pores and on the surface of the konjac sponge.

[0104] (3) Take out the filler after step (2) and immerse it in a CaCl2 solution with a mass concentration of 3.5% for 12 minutes to carry out surface strengthening crosslinking. A gel layer with higher crosslinking density is formed on the surface of the filler, thereby constructing a gradient gel structure with crosslinking density gradually increasing from the inside to the outside.

[0105] (4) Take out the packing material after step (3) and soak it in clean water for 12 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0106] (5) The wet packing obtained in step (4) is dried at 40°C for 11 h to reduce the moisture content of the packing to 6%. The volume of the dried packing is reduced to about 1 / 4 of that before drying, and the weight is reduced by about 92%, thus obtaining the dry intelligent responsive self-absorbing gel biological packing.

[0107] Example 10 This embodiment provides a smart responsive self-absorbing gel biofiller, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 10 min, then take it out and dry it at 105℃ to constant weight. Immerse the dried konjac sponge in a 2.5% CaCl2 solution for 10 min, then take it out and squeeze out the excess CaCl2 solution on the surface and inside, so that the wet weight of the konjac sponge is controlled to be 3.5 times the weight in the dry state, and the pretreated matrix is ​​obtained.

[0108] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 10 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a concentration of 5.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 1.5%; the mass concentration of trehalose was 2.5%; and the mass concentration of resazurin was 0.15%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+ An in-situ cross-linking reaction occurs, forming a gel network containing functional strains, trehalose, and resazurite within the pores and on the surface of the konjac sponge.

[0109] (3) Take out the filler after step (2) and immerse it in a CaCl2 solution with a mass concentration of 5.0% for 5 minutes to carry out surface strengthening crosslinking. A gel layer with higher crosslinking density is formed on the surface of the filler, thereby constructing a gradient gel structure with crosslinking density gradually increasing from the inside to the outside.

[0110] (4) Take out the packing material after step (3) and soak it in clean water for 14 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0111] (5) The wet packing obtained in step (4) is dried at 40°C for 11 h to reduce the moisture content of the packing to 6%. The volume of the dried packing is reduced to about 1 / 4 of that before drying, and the weight is reduced by about 92%, thus obtaining the dry intelligent responsive self-absorbing gel biological packing.

[0112] Example 11 This embodiment provides a smart responsive self-absorbing gel biofiller, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 20 min, and then dry it at 105℃ to constant weight. Immerse the dried konjac sponge in a 1.5% CaCl2 solution for 18 min, and then remove it by squeezing to remove excess CaCl2 solution from the surface and inside, so that the wet weight of the konjac sponge is controlled to be 4 times the weight in the dry state, and the pretreated matrix is ​​obtained.

[0113] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 30 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a strain concentration of 3.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 3.5%; the mass concentration of trehalose was 1%; and the mass concentration of resazurin was 0.4%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+ An in-situ cross-linking reaction occurs, forming a gel network containing functional strains, trehalose, and resazurite within the pores and on the surface of the konjac sponge.

[0114] (3) Take out the filler after step (2) and immerse it in a CaCl2 solution with a mass concentration of 2.5% for 15 minutes to carry out surface strengthening crosslinking. A gel layer with higher crosslinking density is formed on the surface of the filler, thereby constructing a gradient gel structure with crosslinking density gradually increasing from the inside to the outside.

[0115] (4) Take out the packing material after step (3) and soak it in clean water for 10 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0116] (5) The wet packing obtained in step (4) is dried at 40°C for 11 h to reduce the moisture content of the packing to 6%. The volume of the dried packing is reduced to about 1 / 4 of that before drying, and the weight is reduced by about 92%, thus obtaining the dry intelligent responsive self-absorbing gel biological packing.

[0117] Comparative Example 1 This comparative example provides a gel biological filler, the preparation method of which includes the following steps: (1) Konjac glucomannan was dissolved in deionized water at room temperature by stirring to prepare a sol with a mass concentration of 0.6%. The sol was poured into a mold and frozen at -20°C for 6 h. Then it was placed in a freeze dryer and dried for 24 h to obtain konjac glucomannan aerogel. The aerogel was cut into particles with a particle size of about 3-4 mm for later use.

[0118] (2) Take 10 g of the aerogel particles obtained in step (1), immerse them directly in a 2% CaCl2 solution without soaking in water or drying, soak for 20 min, remove them and drain off the excess solution on the surface, so that the wet weight of the particles is controlled to be about 3 times the weight in the dry state, and obtain the pretreated matrix.

[0119] (3) Immerse the pretreated matrix obtained in step (2) in a mixed solution containing functional strains, sodium alginate, trehalose, and resplenium for 20 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a concentration of 6.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 2%; the mass concentration of trehalose was 2%; and the mass concentration of resazurin was 0.1%. During the soaking process, sodium alginate reacted with Ca in the pretreated matrix. 2+ An in-situ cross-linking reaction occurs, forming a gel network containing embedded functional strains, trehalose, and resazurite within the pores and on the surface of the aerogel particles.

[0120] (4) Take out the particles after step (3) and immerse them in a CaCl2 solution with a mass concentration of 4% for 10 minutes to carry out surface strengthening crosslinking.

[0121] (5) Take out the particles processed in step (4) and soak them in clean water for 12 h to remove unreacted CaCl2 and unfixed components, and obtain wet filler.

[0122] (6) The wet packing obtained in step (5) is dried at 40°C for 10 h to reduce the moisture content of the packing to 6% and obtain dry gel biological packing.

[0123] Figure 5The bar chart shows the structural stability comparison between the fillers of Example 1 and Comparative Example 1, with the intact particle rate, edge crack rate, and volume retention rate after drying as the three indicators. The results show that the intact particle rate of the filler in Example 1 is close to 100%, the edge crack rate is only about 5%, and the volume retention rate after drying is about 25%; while the intact particle rate of the filler in Comparative Example 1 is only about 78%, and the edge crack rate is as high as about 34%. This indicates that the gel biofiller of the present invention has excellent anti-breakage and anti-cracking properties during the drying process, effectively avoiding the problems of easy breakage and cracking of conventional materials during drying, and is more suitable for the actual working conditions of in-situ groundwater remediation. Comparative Example 1 uses konjac glucomannan aerogel obtained by direct freeze-drying as the skeleton. Its internal structure is a rigid porous structure formed by brittle ice crystal templates, lacking the elastic fiber network of konjac sponge. During subsequent CaCl2 solution soaking, cross-linking, and drying processes, it is prone to breakage and cracking, resulting in a low intact particle rate, a high edge crack rate, and significantly inferior structural stability compared to Example 1.

[0124] Comparative Example 2 This comparative example provides a gel biofiller, which differs from Example 1 in that the konjac sponge in step (1) is replaced with a chitosan sponge. The remaining steps and parameters are the same as in Example 1.

[0125] Figure 6 The mechanical properties of the fillers in Example 1 and Comparative Example 2 are compared. Figure a shows the compressive stress-strain curve, and Figure b shows the deformation recovery rate histogram. As can be seen from the figures, the compressive strength of Example 1 is significantly higher than that of Comparative Example 2, with a stress exceeding 4.5 MPa at 100% compressive strain and a deformation recovery rate close to 96%. In contrast, the compressive strength of Comparative Example 2 is only about 1.7 MPa, and the deformation recovery rate is about 81%. This indicates that the filler of the present invention possesses excellent mechanical strength and elastic recovery ability, and can resist water erosion and compressive stress under long-term conditions of in-situ groundwater remediation, maintaining a stable pore structure and mechanical properties. Comparative Example 2 uses chitosan sponge as the skeleton material, which has low mechanical strength and poor elastic recovery ability, and is prone to irreversible deformation during crosslinking and drying. Therefore, its mechanical properties are significantly inferior to the konjac sponge skeleton of Example 1.

[0126] Comparative Example 3 This comparative example provides a gel biological filler, the preparation method of which includes the following steps: (1) Soak the konjac sponge in clean water for 15 min, take it out and dry it at 105℃ to constant weight to obtain the pretreated matrix.

[0127] (2) Immerse the pretreated matrix obtained in step (1) in a mixed solution containing functional strains, sodium alginate, trehalose, resplenium, and CaCl2 for 30 min. The functional strain in the mixed solution is *Paracoccus sulfooxidans* 175A1-1, with a strain concentration of 6.0 × 10⁻⁶. 8 CFU·mL -1 The mass concentration of sodium alginate was 2%; the mass concentration of trehalose was 2%; the mass concentration of resazurin was 0.1%; and the mass concentration of CaCl2 was 2%. During the soaking process, sodium alginate reacted with CaCl2 in the mixed solution. 2+ Cross-linking is completed in one step inside the pores and on the surface of the konjac sponge to form a homogeneous gel network.

[0128] (3) Take out the packing material after step (2) and soak it in clean water for 12 h to remove unreacted CaCl2 and unfixed components, and obtain wet packing material.

[0129] (4) The wet packing obtained in step (3) is dried at 40°C for 10 h to reduce the moisture content of the packing to 6% and obtain dry gel biological packing.

[0130] Comparative Example 4 This comparative example provides a gel biological filler, which differs from Example 1 in that: the mass concentration of CaCl2 solution in steps (1) and (3) is the same, which is 2%; the soaking time in step (1) is 15 min; the soaking time in step (3) is 10 min; and the remaining operations are the same as in Example 1.

[0131] Figure 7 Figure 1 compares the retention performance and mass transfer performance of the strains in the packing material of Example 1, Comparative Example 3, and Comparative Example 4. Figure a shows the strain loss rate over time, and Figure b shows the OD (Organizational Degradation) performance. 600 Figure c shows the mass transfer rate change curve. The results indicate that during the 50-day operation of Example 1, the strain loss rate was only about 7%, and the OD... 600 The peak value was low and decreased rapidly, while the mass transfer rate remained at a high level throughout; whereas the strain loss rate and OD of Comparative Examples 3 and 4 were lower. 600 The values ​​are significantly higher, and the mass transfer rate decays faster. This indicates that the internally dense and externally sparse gel network formed by the gradient crosslinking process of this invention can maintain excellent mass transfer efficiency while effectively immobilizing microorganisms and reducing cell loss, which is significantly better than one-step crosslinking or two-step crosslinking processes with equal concentration.

[0132] Comparative Example 5 This comparative example provides a gel biofiller, which differs from Example 1 in that the redox-responsive indicator razorazine is not added to the mixed solution in step (2). The remaining steps and parameters are the same as in Example 1.

[0133] Comparative Example 6 This comparative example provides a gel biofiller, which differs from Example 1 in that trehalose is not added to the mixed solution in step (2). The remaining steps and parameters are the same as in Example 1.

[0134] Comparative Example 7 This comparative example provides a gel biofiller, which differs from Example 1 in that: in the mixed solution of step (2), trehalose is replaced with sucrose, while the mass concentration remains at 2%. The remaining steps and parameters are the same as in Example 1.

[0135] The dried gel bio-fillers prepared in Examples 1, 6, and 7 were stored in a dry environment at room temperature, protected from light. Samples were taken at 0, 10, 20, 30, 40, 50, and 60 days of storage. The activity of microorganisms in the filler samples stored for different times was determined using the ATP bioluminescence method. The activity at storage day 0 was taken as 100% baseline, and the bacterial activity retention rate at each time point was calculated. The filler samples stored for different times were rehydrated and activated according to standard methods, then added to a simulated contaminated groundwater system with an initial DMF concentration of 200 mg / L. The reaction was carried out at 25°C for 48 h, and the DMF concentration in the supernatant was measured to calculate the pollutant degradation rate after 48 h.

[0136] Figure 8 This paper compares the storage stability of Example 1, Comparative Example 6, and Comparative Example 7. Figure a shows the change curve of strain activity retention rate during storage, and figure b shows the change curve of pollutant degradation rate after 48 hours of rehydration. The results show that after 60 days of storage, the strain activity retention rate of the packing material in Example 1 remained above 83%, and the DMF degradation rate after 48 hours of rehydration remained above 88%. In contrast, the strain activity and degradation performance of Comparative Examples 6 and 7 showed significant decline. This indicates that the use of trehalose as a freeze-drying protectant in this invention can significantly improve the storage stability of the dried gel bio-packing material, extend the product shelf life, and provide assurance for industrial production, transportation, and field application.

[0137] To comprehensively evaluate the pollutant degradation performance and strain recovery ability of the various embodiments and comparative samples of this invention, pollutant degradation kinetics and strain activity recovery tests were conducted. The test methods are as follows: 1. Pollutant degradation rate The dried packing materials obtained in Examples 1, 6-11, and Comparative Examples 1-7 were added to 250 mL Erlenmeyer flasks containing 150 mL of simulated contaminated groundwater. The amount of packing material added was 10% of the reaction system volume based on the wet equivalent volume. Except for Example 6, which used petroleum hydrocarbons as the target pollutant, all other samples used DMF as the target pollutant. The initial concentration was 100 mg / L for all samples.-1 .

[0138] Each conical flask was incubated at 10 ℃ and 40 rpm with shaking. Samples were taken at 0, 2, 4, 8, 12, 24, 36, and 48 h to determine the residual pollutant concentration. Pollutant concentration was determined by high-performance liquid chromatography (HPLC). The pollutant degradation rate was calculated using the following formula: Pollutant degradation rate (%) = (C0 - C) t ) / C0× 100% Where C0 is the initial concentration of pollutants, C t Let be the pollutant concentration at time t.

[0139] Figure 9 The pollutant degradation kinetic curves for the packing materials in Examples 1, 6-11, and Comparative Examples 1-7 are shown. The results indicate that the pollutant degradation rates of Examples 1 and 6-11 within 48 h were significantly higher than those of all comparative samples, with Example 1 exhibiting the fastest degradation rate, reaching nearly 100% in the final degradation. The degradation effects of Examples 6-11 were slightly lower than those of Example 1, but still maintained a high level. Among the comparative samples, Comparative Example 5, since it did not affect the activity of the strain, showed degradation performance close to that of the examples; while Comparative Examples 1-4 and 6-7, due to issues such as the lack of backbone materials, cross-linking processes, or protective agents, had significantly lower degradation rates and final degradation rates than the examples of this invention. Comparative Example 6, without trehalose, and Comparative Example 7, with sucrose substitution, showed the worst degradation effects.

[0140] 2. Strain activity recovery rate The dried packing materials obtained in Examples 1, 6-11, and Comparative Examples 1-7 were rehydrated in simulated groundwater at the same mass. Samples were taken after rehydration at 10°C for 0, 1, 2, 4, 6, 8, and 12 hours, respectively. The removed packing materials were dried to remove surface moisture, cut into small pieces, and homogenized with PBS buffer to ensure thorough dispersion of the immobilized bacterial strains within the packing material in the detection system. The ATPase activity of each sample was then measured according to the instructions of the ATPase activity kit. The ATPase activity of the undried wet packing material sample was used as a reference and recorded as 100%. The bacterial activity recovery rate of each sample at different rehydration times was calculated using the following formula: Strain activity recovery rate (%) = E t / E ref × 100% Among them, E t E represents the ATPase activity value of the sample at time t after rehydration. ref The corresponding ATPase activity values ​​are for the wet, fresh packing sample.

[0141] Figure 10The results show the kinetic curves of bacterial activity recovery for the packing materials used in Examples 1, 6-11, and Comparative Examples 1-7. The results indicate that the bacterial activity recovery rate and recovery rate of Examples 1 and 6-11 were significantly better than all comparative samples. The bacterial activity recovery of Example 1 was the fastest, reaching over 90% within 12 hours. The recovery effect of Examples 6-11 was lower than that of Example 1, but still much higher than that of the comparative samples. Among the comparative samples, Comparative Example 6, without trehalose, had the lowest activity recovery rate, followed by Comparative Example 7 with sucrose substitution. Comparative Examples 1-4 had poor fixation due to defects in the skeleton or cross-linking structure, resulting in slow activity recovery after rehydration. Comparative Example 5, without the addition of an indicator, showed an activity recovery effect close to that of the examples.

[0142] To further evaluate the degree of water quality improvement and dissolved organic matter removal effect of groundwater after treatment with different fillers, the present invention conducted three-dimensional fluorescence spectroscopy (EEM) tests on the following groups of effluent.

[0143] Four parallel test systems were constructed: a blank control group, comparative example 1, comparative example 6, and example 1. Comparative examples 1, 6, and 1 were each added with an equal volume of the corresponding prepared dry gel bio-filler, rehydrated and activated, and then placed in a simulated contaminated groundwater system with an initial DMF concentration of 200 mg / L. The blank control group did not add any filler or bacterial strains, but only an equal volume of simulated contaminated groundwater. The degradation reaction was carried out at 25℃ and 150 rpm. After 72 h of reaction, the supernatant of each system was collected, filtered through a 0.22 μm filter membrane, and subjected to three-dimensional fluorescence spectroscopy (EEM). Test conditions: excitation wavelength Ex = 220–400 nm, emission wavelength Em = 260–600 nm, excitation wavelength scan interval 5.0 nm, emission wavelength scan interval 1.0 nm, response time 0.05 s; before the test, ultrapure water was used as a blank for background subtraction. The changes in the type and content of dissolved organic matter (DOM) in the water were evaluated by the position and intensity of characteristic fluorescence peaks.

[0144] Figure 11This is a comparison of the three-dimensional fluorescence spectra (EEM) of effluent from simulated polluted groundwater treated with the blank control group, Example 1, Comparative Example 1, and Comparative Example 6. Specifically: a) Comparative Example 6 (without trehalose): The strain lacked protection, resulting in significant inactivation and lysis during drying and operation, releasing intracellular organic matter. The effluent exhibited the highest fluorescence peak intensity, indicating the worst water quality. b) Blank control group: No treatment was applied, maintaining the initial pollution level in the water. Significant fluorescence peaks were observed for organic matter. c) Comparative Example 1 (konjac aerogel carrier): The carrier was brittle and easily damaged, resulting in poor strain immobilization and only weak adsorption. The fluorescence peak intensity was slightly lower than the blank group, indicating limited degradation. d) Example 1 group: The strain exhibited high activity and strong immobilization, efficiently degrading mineralized organic pollutants. Dissolved organic matter in the effluent was significantly reduced, and the fluorescence peak almost disappeared, indicating the best water quality improvement.

[0145] Application Example 1 This application example provides an in-situ groundwater remediation method. The method utilizes the intelligent responsive self-absorbing gel bio-filler prepared in Example 1 to remediate groundwater contaminated with N,N-dimethylformamide (DMF) downstream of a chemical plant. The specific steps are as follows: (1) Constructing an in-situ remediation system Three remediation wells were installed along the groundwater flow direction within the contaminated area. A schematic diagram of the remediation well installation is shown below. Figure 12 As shown. Repair well 1 has a diameter of 150 mm and a depth of 7 m, with a spacing of 2 m between adjacent repair wells. The wells are filled with dry-state intelligent responsive self-absorbing gel biofiller 2 prepared in Example 1, with a filling amount of 6% of the effective volume of the repair well. An aeration system is set up, including an aeration fan 4 installed on the ground, an aeration pipe 5 connecting each repair well, and an aeration head 3 installed at the bottom of each repair well.

[0146] After the dried packing material is put into the repair well, it begins to absorb water and expand upon contact with groundwater. After about 2 hours, the packing material volume returns to its original size before drying, and its morphology changes from a dried, shrunken state to a semi-transparent, milky-white, elastic, and plump body. The functional strains regain their metabolic activity, enabling immediate use without the need for on-site activation treatment.

[0147] (2) Start the repair process Air is continuously introduced into each repair well through the aeration system to maintain an initial aeration intensity of 4.0 m. 3 ·(m 2 ·h) -1 The airflow generated by aeration carries groundwater through the pores of the packing material, allowing dissolved DMF to come into full contact with the sulfur-oxidizing paracocci in the packing material. The microorganisms use DMF as a carbon and nitrogen source for aerobic metabolism, gradually degrading it into dimethylamine and formic acid, and further mineralizing it into carbon dioxide, water, and ammonia nitrogen.

[0148] (3) Operation status monitoring and dynamic control During the remediation operation, the color change of the resamarium indicator in the packing material was observed regularly. In the initial stage of remediation, the DMF concentration in the groundwater was approximately 200 mg / L, with vigorous microbial metabolism. The packing material maintained a reducing environment, and the resamarium existed in its reduced state (halogenated), resulting in a pink color in the packing material. By day 5, the DMF concentration had decreased to approximately 15 mg / L, but the packing material remained pink, indicating that the microorganisms were still actively degrading the material.

[0149] By day 7, the DMF concentration had decreased to 3.2 mg / L, remaining consistently below the preset remediation target limit (10 mg / L). At this point, the packing material gradually changed from pink to blue, indicating that the available substrate for microorganisms had been largely depleted, the metabolic intensity had significantly decreased, the redox potential inside the packing material had rebounded, and the resazurium had changed from a reduced state to an oxidized state. This signal change clearly indicates that the packing material has completed the degradation of the main pollutants and has entered the disposal stage.

[0150] At this point, the aeration intensity of each repair well was increased from the initial 4.0 m. 3 ·(m 2 ·h) -1 Increased to 10.0 m 3 ·(m 2 ·h) -1 Under enhanced aeration conditions, increased hydraulic shear and sufficient dissolved oxygen jointly promote the biodegradation of the konjac sponge skeleton and calcium alginate gel network by aerobic microorganisms. The konjac glucomannan backbone is hydrolyzed and broken by glucomannanase secreted by microorganisms, and calcium ions in the calcium alginate gel undergo ion exchange with sodium and potassium ions in the groundwater, gradually dissociating the cross-linked network. The packing material disintegrates and disperses layer by layer from the outside in. By the 30th day of operation, the packing material has been basically completely absorbed, with no obvious solid residue in the well, eliminating the need for retrieval and recovery.

[0151] Three remediation wells deployed along the groundwater flow direction formed a continuous reaction barrier. The upstream well intercepted and degraded approximately 65% ​​of the DMF, the midstream well further removed approximately 25%, and the downstream well reduced the residual DMF to below 3.2 mg / L. The azadirachte indicator signal of the packing material in each well independently reflected its operating status: the upstream well changed color first on day 5, the midstream well on day 6, and the downstream well on day 7. Based on the signals from each well, the aeration intensity was increased accordingly, enabling independent control of each well and phased completion of the remediation.

[0152] Testing showed that the DMF concentration in the groundwater decreased from the initial 200 mg / L to 3.2 mg / L after remediation, achieving a removal rate of 98.4%. The remediation process had no adverse effects on conventional water quality indicators such as pH, oxygen consumption, and ammonia nitrogen, and the biodegradation and disposal of the filler material resulted in no secondary pollution.

[0153] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A smart responsive self-absorbing gel biofiller, characterized in that, It includes a matrix framework, a gel network encapsulating the interior and surface of the matrix framework, and functional strains, bioactive protectants, and environmentally responsive indicators immobilized in the gel network; The matrix skeleton is konjac sponge; The gel network is formed by cross-linking alginate and divalent metal cations, and the gel network has a gradient structure in which the cross-linking density gradually increases from the inside to the outside within the filler. The environmentally responsive indicator is a redox-responsive indicator, which can generate color or fluorescence signal changes in response to changes in the redox potential inside the filler.

2. The intelligent responsive self-absorbing gel biofiller according to claim 1, characterized in that: The divalent metal cation is calcium ion, and the alginate is sodium alginate.

3. The intelligent responsive self-absorbing gel biofiller according to claim 1, characterized in that: The redox-responsive indicator is one or more of resazurin, thiazolyl blue, triphenyltetrazolium chloride, and methylene blue.

4. The intelligent responsive self-absorbing gel biofiller according to claim 1, characterized in that: The functional strains are microorganisms capable of degrading one or more of the following organic pollutants: N,N-dimethylformamide, toluene, xylene, benzene, ethylbenzene, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, petroleum hydrocarbons, methyl tert-butyl ether, and nitro aromatic hydrocarbons.

5. The intelligent responsive self-absorbing gel biofiller according to claim 4, characterized in that: The functional strain is selected from one or more of the following genera: Paracoccus ( Paracoccus ), Pseudomonas spp. Pseudomonas ), Rhodococcus spp. ( Rhodococcus Acinetobacter spp. Acinetobacter ), Bacillus spp. ( Bacillus ), Dehalogenated Pseudomonas ( Dehalococcoides ).

6. The intelligent responsive self-absorbing gel biofiller according to claim 5, characterized in that: The functional strain is selected from one or more of the following species: *Paracoccus sulfooxidans* (… Paracoccus sulfuroxidans ), denitrifying paracocci ( Paracoccus denitrificans ), Paracoccus variegata ( Paracoccus versutus ); Pseudomonas aeruginosa ( Pseudomonas aeruginosa ); Rhodococcus ( Rhodococcus ruber ), Pyridine-loving Rhodococcus ( Rhodococcus pyridinivorans Acinetobacter baumannii (); Acinetobacter baumannii Acinetobacter johnsonii ( ) Acinetobacter johnsonii ); Bacillus pumilus ( Bacillus pumilus ); and dehalogenated cactus ( Dehalococcoides mccartyi ).

7. The intelligent responsive self-absorbing gel biofiller according to claim 1, characterized in that: The bioactive protective agent is trehalose.

8. A method for preparing a smart responsive self-absorbing gel biofiller according to any one of claims 1-7, characterized in that, Includes the following steps: (1) Soak the konjac sponge in clean water, take it out and dry it to constant weight; immerse the dried konjac sponge in a solution containing divalent metal cations, soak it, take it out and remove the excess solution from the surface and inside, so that the wet weight of the konjac sponge is controlled at 2 to 4 times the weight in the dry state, and obtain the pretreated matrix. (2) Immerse the pretreated matrix in a mixed solution containing functional strains, alginate, bioactive protectant and redox-responsive indicator; (3) Take out the filler after soaking in step (2) and immerse it in a solution containing divalent metal cations for soaking; the concentration of the solution containing divalent metal cations in step (3) is greater than the concentration of the solution containing divalent metal cations in step (1); (4) Take out the filler after soaking in step (3), soak it in clean water to remove unreacted components, and obtain wet filler; (5) Dry the wet packing material to reduce the moisture content of the packing material to 5%~10% to obtain the intelligent responsive self-absorbing gel biological packing material.

9. The preparation method according to claim 8, characterized in that: The mass concentration of the solution containing divalent metal cations in step (1) is 0.5%~2.5%, and the konjac sponge is soaked in the solution containing divalent metal cations for 10~20 minutes.

10. The preparation method according to claim 8, characterized in that: The solution containing divalent metal cations is a CaCl2 solution.

11. The preparation method according to claim 8, characterized in that: The soaking time in step (2) is 10~30 minutes.

12. The preparation method according to claim 8, characterized in that: The concentration of the functional strain in the mixed solution in step (2) is 2.0 × 10⁻⁶. 8 ~8.0×10 8 CFU·mL -1 The mass concentration of alginate is 1%~4%, the mass concentration of bioactive protective agent is 1%~4%, and the mass concentration of redox-responsive indicator is 0.01%~0.5%.

13. The preparation method according to claim 12, characterized in that: The concentration of the functional strain in the mixed solution in step (2) is 5.0 × 10⁻⁶. 8 ~7.0×10 8 CFU·mL -1 The mass concentration of alginate is 1.5%~3%, the mass concentration of bioactive protective agent is 1.5%~3%, and the mass concentration of redox-responsive indicator is 0.05%~0.2%.

14. The preparation method according to claim 8, characterized in that: The mass concentration of the solution containing divalent metal cations in step (3) is 2.5% to 5.0%, and the soaking time is 5 to 15 min.

15. The preparation method according to claim 8, characterized in that: The soaking time in clean water in step (4) is 10~14 h.

16. The preparation method according to claim 8, characterized in that: The drying temperature in step (5) is 30~60℃ and the drying time is 5~12 h.

17. The preparation method according to claim 16, characterized in that: The drying temperature in step (5) is 35~45℃.

18. The preparation method according to claim 8, characterized in that: Step (5) After drying, the volume of the filler is reduced to less than 1 / 3 of that before drying, and the weight is reduced by more than 90%.

19. A groundwater in-situ remediation equipment, characterized in that, Includes a repair well system, an aeration system, and a smart responsive self-absorbing gel biofiller filled within the repair well system; The repair well system includes multiple repair wells arranged according to the direction of groundwater flow; The aeration system includes an aeration blower, an aeration pipe, and an aeration head installed at the bottom of the repair well for supplying air to the repair well. The aeration pipe connects the aeration blower to the aeration head at the bottom of each repair well. The intelligent responsive self-absorbing gel biofiller is the intelligent responsive self-absorbing gel biofiller according to any one of claims 1-7, or is prepared by the preparation method according to any one of claims 8-18.

20. The groundwater in-situ remediation equipment according to claim 19, characterized in that: The diameter of the repair well is 100-250 mm, the depth is 6-8 m, and the distance between adjacent repair wells is 1-3 m.

21. The groundwater in-situ remediation equipment according to claim 19, characterized in that: The filling amount of the intelligent responsive self-absorbing gel biofiller is 2% to 15% of the effective volume of the repair well.

22. The groundwater in-situ remediation equipment according to claim 21, characterized in that: When the concentration of pollutants in groundwater exceeds the standard limit but is within 10 times the limit, the filling amount of the filler is 2% to 8% of the effective volume of the remediation well; when the concentration of pollutants in groundwater exceeds the standard limit by more than 10 times, the filling amount of the filler is 9% to 15% of the effective volume of the remediation well.

23. A method for in-situ remediation of groundwater, characterized in that, Includes the following steps: (1) One or more remediation wells are set up in the contaminated area according to the groundwater flow direction, the remediation wells are filled with intelligent responsive self-absorbing gel biological filler, and an aeration system for supplying air to the remediation wells is set up; the intelligent responsive self-absorbing gel biological filler is the intelligent responsive self-absorbing gel biological filler according to any one of claims 1-7, or is prepared by the preparation method according to any one of claims 8-18. (2) The aeration system continuously supplies air to the repair well to maintain the initial aeration intensity, so that the functional strains in the packing can degrade organic pollutants in the groundwater. (3) Monitor the color or fluorescence signal change of the environmental responsive indicator in the packing, and judge the operating status of the packing based on the signal change; when the signal change of the environmental responsive indicator indicates that the packing has entered the disposal stage from the pollutant degradation stage, increase the aeration intensity of the aeration system to 1.5 to 3 times the initial aeration intensity to accelerate the biodegradation of the packing and make the packing disposed of in situ in the repair well.

24. The in-situ groundwater remediation method according to claim 23, characterized in that: The initial aeration intensity mentioned in step (2) is 1.0~5.0 m. 3 ·(m 2 ·h) -1 .

25. The in-situ groundwater remediation method according to claim 23, characterized in that: In step (2), the aeration system supplies the corresponding gas to the repair well according to the metabolic type of the functional strain; when the functional strain is an aerobic or facultative anaerobic bacterium, the supplied gas is air or oxygen; when the functional strain is an anaerobic bacterium, the supplied gas is an oxygen-free gas.

26. The in-situ groundwater remediation method according to claim 23, characterized in that: In step (3), when the color or fluorescence signal of the environmentally responsive indicator changes from a reduced state characteristic signal to an oxidized state characteristic signal, it is determined that the filler has entered the disposal stage from the pollutant degradation stage.

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