Repair agent and method for treating volatile pollutants in underground water

Abstract

The invention discloses a repairing agent and method for treating volatile pollutants in underground water, and the repairing agent comprises a first hollow ball, a second hollow ball rotatably arranged in the first hollow ball, and oxygen release particles and complex microbial inoculant particles filled in the second hollow ball, the first hollow ball and the second hollow ball are both provided with a plurality of holes which are in butt joint through mutual rotation, the oxygen release particles and the complex microbial inoculant particles are filled according to n [1 / 2, 3 / 2] and n [1 / 5, 1 / 2] respectively, and n is the total mass of the first hollow ball and the second hollow ball. According to the invention, through the drug release frame body formed by the first hollow spheres and the second hollow spheres, the oxygen release particles and the complex microbial inoculant particles can be gradually released, so that the distribution uniformity of the oxygen release particles and the complex microbial inoculant particles in to-be-treated underground water is improved, and the biodegradation treatment effect of the drug release frame body on volatile pollutants in the underground water is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to a repair agent and a method for treating volatile pollutants in groundwater. Background Art

[0002] Volatile pollutants in groundwater, especially volatile organic compounds (VOCs), pose a serious threat to groundwater quality. Common volatile organic pollutants in groundwater include benzene series (such as benzene, toluene, xylene, etc.) and halogenated hydrocarbons (such as trichloroethylene, chloroform, trichloroethane, etc.). These pollutants are highly volatile, permeable, and harmful, and are not easy to be detected in a timely and accurate manner.

[0003] The sources of volatile organic pollutants in groundwater are diverse, mainly including: 1) Industrial waste: Many industrial processes produce waste containing various chemicals, including many volatile organic compounds. These wastes may seep into groundwater after being discharged or improperly handled, causing pollution; 2) Agricultural activities: In agricultural production, pesticides and fertilizers are widely used, and some of these chemicals are volatile organic compounds. These chemicals may enter groundwater through leakage or runoff during use; 3) Urban sewage treatment plants: During the treatment of urban sewage, some volatile organic compounds cannot be completely removed and may be discharged into the environment through effluent water and eventually absorbed by groundwater bodies; 4) Underground oil storage facilities: Due to aging of facilities, poor maintenance or accidents, underground oil storage facilities may leak, causing volatile organic compounds to seep into groundwater; 5) Improper waste disposal: When waste is improperly handled, dumped or buried, volatile organic compounds may seep out and contaminate groundwater.

[0004] However, the removal effect of volatile organic pollutants in groundwater in the existing technology still needs to be improved. The use of traditional flushing methods has the problem of incomplete removal of groundwater pollution, while the use of in situ bioremediation methods may cause some volatile pollutants to spill and pollute the environment. Therefore, a new method for remediating volatile pollutants in groundwater is needed to optimize the above problems. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a repair agent and method for treating volatile pollutants in groundwater.

[0006] The technical solution of the present invention is: a remediation agent for treating volatile pollutants in groundwater, comprising: a first hollow sphere, a second hollow sphere rotatably arranged in the first hollow sphere, and oxygen-releasing particles and composite bacterial agent particles filled in the second hollow sphere, the first hollow sphere and the second hollow sphere are both provided with a plurality of holes for docking by rotating with each other, and the oxygen-releasing particles and the composite bacterial agent particles are filled according to n[1 / 2, 3 / 2] and n[1 / 5, 1 / 2] respectively, where n is the total mass of the first hollow sphere and the second hollow sphere.

[0007] Furthermore, the first hollow sphere, the second hollow sphere and the oxygen-releasing particles are all made by solidifying an oxygen-releasing adhesive in a mold.

[0008] Description: The use of oxygen-releasing glue to prepare the first hollow ball and the second hollow ball can slowly release oxygen in the groundwater to promote the respiratory metabolism of indigenous microorganisms in the groundwater, thereby degrading pollutants in the groundwater. The first hollow ball and the second hollow ball can be naturally degraded on the basis of a framework by solidifying the oxygen-releasing glue, thereby avoiding secondary pollution of the groundwater or the need to recycle the first hollow ball and the second hollow ball.

[0009] At the same time, in order to facilitate the assembly of the first hollow ball and the second hollow ball, a hemisphere method can be used for preparation. Specifically, the first hollow ball and the second hollow ball are prepared in the form of two hemispheres, and after curing and demoulding, the two hemispheres are spliced ​​to form the first hollow ball or the second hollow ball.

[0010] Furthermore, the oxygen-releasing colloid is prepared by mixing 20 to 40 parts of gelatin and 60 to 120 parts of agar as a matrix, and adding 100 to 150 parts of calcium peroxide, 15 to 35 parts of tourmaline powder, and 2 to 8 parts of sodium bicarbonate into the matrix and mixing well to obtain the oxygen-releasing colloid.

[0011] Description: Agar is a polysaccharide extracted from red algae such as Agar-agar and Glechoma longituba. It is a gelling agent with excellent performance. Gelatin is a natural protein with good hardening effect. By introducing a certain amount of gelatin into agar, the texture of agar can be made more compact, thereby meeting the use requirements of the first hollow ball and the second hollow ball.

[0012] Calcium peroxide can slowly release oxygen in water. Compared with some materials that quickly release oxygen, the oxygen release process of calcium peroxide is more gradual, thereby avoiding the impact on the environment caused by a sharp increase in oxygen concentration. At the same time, introducing an appropriate amount of tourmaline powder into the oxygen-releasing adhesive can not only effectively enhance the structural strength of the first hollow ball and the second hollow ball prepared by the oxygen-releasing adhesive, but also improve the repair treatment effect of the repair agent.

[0013] The processing performance of the oxygen-releasing adhesive can be improved by introducing a small amount of sodium bicarbonate. The carbon dioxide gas produced by the decomposition of sodium bicarbonate helps to disperse and mix the calcium peroxide and the like in the oxygen-releasing adhesive, making the components in the oxygen-releasing adhesive more uniform, thereby optimizing the use effect of the first hollow sphere, the second hollow sphere or the oxygen-releasing particles prepared by the oxygen-releasing adhesive.

[0014] Furthermore, the curing method of the oxygen-releasing adhesive liquid is: subjecting the oxygen-releasing adhesive liquid to ultrasonic treatment and continuous stirring, heating it to 45-55°C and keeping it warm for 20-40 minutes to make the oxygen-releasing adhesive liquid expandable, then injecting it into a mold for preparing the first hollow sphere, the second hollow sphere or the oxygen-releasing particles, cooling and curing it to obtain the first hollow sphere, the second hollow sphere or the oxygen-releasing particles.

[0015] Description: By using ultrasonic treatment to disperse the components in the oxygen-releasing adhesive liquid and heating it to the above-mentioned temperature range, the oxygen-releasing adhesive liquid can be effectively expanded, thereby better dispersing components such as tourmaline powder in the oxygen-releasing adhesive liquid, making the components in the oxygen-releasing adhesive liquid more uniform, and improving the use effect of the oxygen-releasing adhesive liquid.

[0016] Furthermore, the second hollow sphere has a partition layer that divides the interior of the second hollow sphere into at least two cavities, and the cavities are respectively filled with oxygen-releasing particles or composite bacterial agent particles.

[0017] Description: By dividing the interior of the second hollow sphere into at least two cavities, the oxygen-releasing particles and the composite bacterial agent particles can be loaded separately by utilizing the cavity setting. Since mixed loading may result in only the release of oxygen-releasing particles or the composite bacterial agent particles per unit time, such a setting can avoid the release of oxygen-releasing particles and composite bacterial agent particles per unit time being affected by random mixing, thereby improving the use effect of the repair agent.

[0018] Furthermore, the second hollow ball is provided with a counterweight or blades for making it rotate, and the counterweight and blades are both made by curing oxygen-releasing glue in a mold.

[0019] Description: By arranging a counterweight or blade on the second hollow ball, the second hollow ball can be better rotated relative to the first hollow ball, so that the holes of the first hollow ball and the second hollow ball can be docked to release oxygen-releasing particles or composite bacterial agent particles. At the same time, it should be noted that the blade is arranged to extend from the second hollow ball to the outside of the first hollow ball to ensure that the blade is in contact with the water flow or air flow.

[0020] Furthermore, the composite bacterial agent granules are prepared by mixing and granulating 10 to 20 parts of mixed bacterial powder, 5 to 10 parts of starch, 3 to 8 parts of diatomaceous earth, and 8 to 12 parts of water, wherein the mixed bacterial powder is composed of Bacillus subtilis, Acinetobacter baumannii, and Rhodococcus in a mass ratio of 2 to 5:1 to 2:0.5 to 1.

[0021] Description: Bacillus subtilis can use organic matter in water as an energy source and convert it into harmless substances. It can also adsorb heavy metal ions and other harmful substances, thereby reducing the concentration of heavy metal ions in groundwater. It can also inhibit the growth of pathogens and harmful microorganisms in groundwater, help promote the degradation and purification ability of indigenous microorganisms, and improve the self-purification ability of water bodies; while Acinetobacter baumannii can use a variety of organic pollutants as carbon sources and energy sources, such as polycyclic aromatic hydrocarbons, pesticides, dyes, etc., thereby improving the quality of groundwater; Rhodococcus can degrade DCM and benzene substances, such as Rhodococcus EH831, which can effectively remove organic chlorine pollutants in groundwater, thereby reducing volatile pollutants in groundwater; the use of the above-mentioned compound mixed bacterial powder can assist in strengthening the water purification ability of indigenous microorganisms in groundwater and enhance the biodegradation and removal of volatile pollutants in groundwater.

[0022] The present invention also provides a method for treating a volatile pollutant in groundwater using a repair agent, comprising the following steps:

[0023] Step 1, injecting the repair agent into the bottom of the contaminated groundwater along with the mixed gas, the amount of the repair agent added being 8-13% of the mass of the contaminated groundwater;

[0024] Step 2: As the mixed gas rises, some volatile pollutants in the groundwater will overflow with the mixed gas, and the gas will be collected and processed using the gas collection system.

[0025] Step 3: As the mixed gas rises, the remediation agent rotates under the impetus of water flow and / or air flow, slowly releasing the oxygen-releasing particles and the composite bacterial agent particles. At the same time, the oxygen released by the remediation agent promotes the biodegradation of other volatile pollutants by indigenous microorganisms and microorganisms of the composite bacterial agent in the groundwater.

[0026] Furthermore, the mixed gas is a mixed gas composed of ozone and air in a volume ratio of 1 to 2:7.

[0027] Note: A certain amount of ozone in the mixed gas can partially oxidize difficult-to-decompose organic matter to increase its biodegradability. Mixing ozone in the above proportion can avoid excessive ozone concentration that may kill a large number of original indigenous microorganisms in the groundwater, affecting the effect of subsequent bioremediation.

[0028] The beneficial effects of the present invention are:

[0029] (1) The remediation agent for treating volatile pollutants in groundwater of the present invention can release oxygen-releasing particles and composite bacterial agent particles in a gradual manner through a drug-releasing frame composed of a first hollow sphere and a second hollow sphere, thereby improving the distribution uniformity of the oxygen-releasing particles and the composite bacterial agent particles in the groundwater to be treated and enhancing its biodegradation treatment effect on volatile pollutants in groundwater.

[0030] (2) The method for treating volatile pollutants in groundwater of the present invention can effectively remove volatile pollutants in groundwater through an optimized flushing method combined with an in-situ bioremediation method, thereby avoiding secondary pollution to the surrounding environment. In addition, under the action of air flow or water flow, the structure of the repair agent can cooperate with the oxygen-releasing particles and the composite bacterial agent particles to gradually release the oxygen-releasing particles and the composite bacterial agent particles, thereby improving the distribution uniformity of the oxygen-releasing particles and the composite bacterial agent particles in the groundwater to be treated. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the simulation structure of the repair agent of Example 1 and Examples 4-13 of the present invention.

[0032] Figure 2 It is a schematic diagram of the simulated internal structure of the repair agent of Example 1 and Examples 4-13 of the present invention.

[0033] Figure 3 It is a schematic diagram of the simulation structure of the repair agent of Example 3 of the present invention.

[0034] Figure 4 This is the relationship between the purge time and response value of 12 representative VOCs in the experimental examples of the present invention.

[0035] Figure 5 This is the relationship between the desorption time and response value of 12 representative VOCs in the experimental examples of the present invention. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with specific implementation methods to better reflect the advantages of the present invention.

[0037] Example 1: A remediation agent for treating volatile pollutants in groundwater, such as Figure 1 , Figure 2As shown, it includes: a first hollow ball, a second hollow ball rotatably arranged in the first hollow ball, and oxygen-releasing particles and composite bacterial agent particles filled in the second hollow ball, the first hollow ball and the second hollow ball are both provided with a plurality of holes for docking by mutual rotation, the second hollow ball is provided with a partition layer for dividing the interior of the second hollow ball into two cavities, and the two cavities are respectively filled with oxygen-releasing particles and composite bacterial agent particles, the first hollow ball, the second hollow ball, and the oxygen-releasing particles are all made by curing oxygen-releasing glue in a mold, and the second hollow ball is provided with a counterweight block (not shown in the figure, located at Figure 2 The left side upper and lower hemisphere joint has the dimensions of 6mm in length × 6mm in width × 6mm in height). The counterweight is specifically formed by splicing the raised parts of the molds of the two hemispheres.

[0038] Wherein, n is the total mass of the first hollow sphere and the second hollow sphere, n is 20g, and the oxygen-releasing particles and the composite bacterial agent particles are filled according to 20g and 5g respectively, the wall thickness of the first hollow sphere and the second hollow sphere is 3mm, the particle size of the oxygen-releasing particles and the composite bacterial agent particles is 2mm, and the aperture of the hole on the first hollow sphere and the second hollow sphere is 3mm;

[0039] The oxygen-releasing glue liquid is composed of 35 parts of gelatin and 105 parts of agar as a matrix, and 138 parts of calcium peroxide, 27 parts of tourmaline powder (particle size 0.2-0.5 mm), and 6 parts of sodium bicarbonate are added to the matrix, and mixed to obtain the oxygen-releasing glue liquid. The solidification method of the oxygen-releasing glue liquid is as follows: the oxygen-releasing glue liquid is subjected to ultrasonic treatment and continuously stirred, heated to 50° C. and kept warm for 35 minutes to make the oxygen-releasing glue liquid bulky, and then injected into a mold for preparing the first hollow ball, the second hollow ball or the oxygen-releasing particles, and cooled and solidified to obtain the first hollow ball, the second hollow ball or the oxygen-releasing particles;

[0040] The composite bacterial agent granules are prepared by mixing and granulating 17 parts of mixed bacterial powder, 8 parts of starch, 5 parts of diatomaceous earth and 11 parts of water in proportion by mass, wherein the mixed bacterial powder is composed of Bacillus subtilis, Acinetobacter baumannii and Rhodococcus in a mass ratio of 15:8:4.

[0041] Example 2: This example provides a method for treating volatile pollutants in groundwater using the repair agent of Example 1, comprising the following steps:

[0042] Step 1, injecting the repair agent into the bottom of the contaminated groundwater along with the mixed gas, the amount of the repair agent added is 8-13% of the mass of the contaminated groundwater, and the amount of the mixed gas introduced is sufficient. It can be understood that when the gas collection system cannot collect volatile pollutants and the repair agent is added, the injection of the mixed gas can be stopped. The mixed gas is a mixed gas composed of ozone and air in a volume ratio of 1-2:7;

[0043] Step 2: As the mixed gas rises, some volatile pollutants in the groundwater will overflow with the mixed gas, and the gas will be collected and processed using the gas collection system.

[0044] Step 3: As the mixed gas rises, the remediation agent rotates under the impetus of water flow and / or air flow, slowly releasing the oxygen-releasing particles and the composite bacterial agent particles. At the same time, the oxygen released by the remediation agent promotes the biodegradation of other volatile pollutants by indigenous microorganisms and microorganisms of the composite bacterial agent in the groundwater.

[0045] Embodiment 3: This embodiment differs from Embodiment 1 in that Figure 3 As shown, the two ends of the second hollow ball each have a blade for rotating it, the blade is made by curing oxygen-releasing glue in a mold, the blade is located outside the first hollow ball, and the shaft portion of the blade penetrates the first hollow ball and is fixedly bonded to the second hollow ball.

[0046] Example 4: This example is different from Example 1 in that n is the total mass of the first hollow sphere and the second hollow sphere, n is 20 g, and the oxygen-releasing particles and the composite bacterial agent particles are filled at 10 g and 4 g, respectively.

[0047] Example 5: This example is different from Example 1 in that n is the total mass of the first hollow sphere and the second hollow sphere, n is 20 g, and the oxygen-releasing particles and the composite bacterial agent particles are filled in amounts of 30 g and 10 g, respectively.

[0048] Example 6: This example is different from Example 1 in that, by mass, the oxygen-releasing colloid is prepared by mixing 20 parts of gelatin and 60 parts of agar as a matrix, and 100 parts of calcium peroxide, 15 parts of tourmaline powder, and 2 parts of sodium bicarbonate are added to the matrix and mixed to obtain the oxygen-releasing colloid.

[0049] Example 7: This example is different from Example 1 in that, by mass, the oxygen-releasing colloid is prepared by mixing 40 parts of gelatin and 120 parts of agar as a matrix, and 150 parts of calcium peroxide, 35 parts of tourmaline powder, and 8 parts of sodium bicarbonate are added to the matrix and mixed to obtain the oxygen-releasing colloid.

[0050] Example 8: This example is different from Example 1 in that the method for curing the oxygen-releasing adhesive liquid is as follows: the oxygen-releasing adhesive liquid is subjected to ultrasonic treatment and continuous stirring, heated to 45°C and kept warm for 20 minutes to make the oxygen-releasing adhesive liquid expandable, and then injected into a mold for preparing the first hollow sphere, the second hollow sphere or the oxygen-releasing particles, and cooled and solidified to obtain the first hollow sphere, the second hollow sphere or the oxygen-releasing particles.

[0051] Example 9: This example is different from Example 1 in that the method for curing the oxygen-releasing adhesive liquid is as follows: the oxygen-releasing adhesive liquid is subjected to ultrasonic treatment and continuous stirring, heated to 55°C and kept warm for 40 minutes to make the oxygen-releasing adhesive liquid expandable, and then injected into a mold for preparing the first hollow sphere, the second hollow sphere or the oxygen-releasing particles, and cooled and solidified to obtain the first hollow sphere, the second hollow sphere or the oxygen-releasing particles.

[0052] Example 10: This example is different from Example 1 in that, by weight, the composite bacterial agent granules are prepared by mixing and granulating 10 parts of mixed bacterial powder, 5 parts of starch, 3 parts of diatomaceous earth, and 8 parts of water.

[0053] Example 11: This example is different from Example 1 in that, by weight, the composite bacterial agent granules are prepared by mixing and granulating 20 parts of mixed bacterial powder, 10 parts of starch, 8 parts of diatomaceous earth, and 12 parts of water.

[0054] Example 12: This example is different from Example 1 in that the mixed bacterial powder consists of Bacillus subtilis, Acinetobacter baumannii, and Rhodococcus in a mass ratio of 4:2:1.

[0055] Example 13: This example is different from Example 1 in that the mixed bacterial powder consists of Bacillus subtilis, Acinetobacter baumannii, and Rhodococcus in a mass ratio of 5:2:1.

[0056] Experimental example:

[0057] 1. Instruments and Reagents

[0058] 1) Instrument: portable gas chromatograph-mass spectrometer (HAPSITE ER, INFICON), purge-trap instrument and automatic purge injector (HAPSITE accessory, INFICON), chromatographic column: DB-1 (30m×0.32mm×0.4μm);

[0059] 2) Standards and reagents: 59 VOCs mixed standards (HJ 605-2011 Determination of volatile organic compounds in soil and sediments, catalog number: CDAA-M-629034-AE-1mL, concentration: 2000mg / L) (Shanghai ANPEL Company);

[0060] 3) 6 VOCs mixed standard (Product No.: CDAA-M-629053-AE-1mL, Concentration: 2000mg / L) (Shanghai ANPEL Company);

[0061] 4) Internal standard substances: chlorobenzene-D8 (internal standard), fluorobenzene (alternative) (Product No.: CDAA-M-690055-AE-1mL, concentration: 2000 mg / L), stored at -20°C;

[0062] 5) Methanol (pesticide grade): Dima Company; 500mL volumetric flask: Grade A; 2mL volumetric vial; ultrapure water (purified by MILLI-Q pure water system);

[0063] 6) GC-MS carrier gas nitrogen: purity above 99.999%;

[0064] 7) Gas-tight micro-syringe: 10μL, 50μL, 100μL.

[0065] 2. Instrument conditions and optimization

[0066] 1) Purge and capture conditions: According to the different retention time periods of the components, 12 representative VOCs were selected, including halogenated hydrocarbons, benzene series, and chlorobenzenes. Under the condition of ensuring the consistency of other conditions, the response value of the mixed standard with a concentration of 20μg / L was obtained by analyzing under different purge times (3min, 5min, 6min, 8min, and 12min). The larger the response value, the higher the capture efficiency, so as to determine the optimal purge time, and draw a relationship diagram between purge time and response value, as shown in the figure below: Figure 4 As shown, the optimal purge time is 6 minutes.

[0067] 2) Desorption time: When other conditions are the same, the response peak area of ​​the mixed standard with a concentration of 20 μg / L is detected under different desorption times (0.5 min, 1 min, 2 min, 3 min and 4 min), and a relationship diagram between desorption time and response value is drawn, as shown in Figure 2. Figure 5 As shown, 1 min is selected as the optimal parsing time.

[0068] 3) Gas chromatograph conditions: Heating program: 60 °C for 3 min, then increase to 100 °C at 6 °C / min, then increase to 180 °C at 12 °C / min, and hold for 6 min, a total of 22 min 20 s, without split mode;

[0069] 4) Mass spectrometry conditions: Scanning range: m / z 41-250 amu, ionization energy 70 eV; ion source temperature: 230°C; quadrupole temperature: 150°C; Scanning mode: full scan (SCAN).

[0070] 3. Based on the above instruments and parameters, and in accordance with the "Regional Groundwater Pollution Investigation and Evaluation Standards", the groundwater VOCs in a certain area of ​​the city were detected, and the repair agent of Example 1 and the method of Example 2 were used to repair the groundwater for 30 days, and the degradation rate of VOCs was detected, with toluene as a reference. The results are shown in Table 1 below:

[0071] Table 1 VOCs degradation rate in groundwater

[0072] Group Toluene degradation rate / % Example 1 96.37

[0073] It can be seen from the results in Table 1 above that the use of the repair agent and the repair method of the present invention for groundwater treatment can effectively degrade VOCs in groundwater. Taking toluene as an example, the degradation rate can reach 96.37%. The treated groundwater meets the requirements of the groundwater quality standard GB / T 14848-2017.

[0074] At the same time, in order to verify the use effect of the repair agent of the present invention, the oxygen-releasing particles and the composite bacterial agent particles are directly injected into the bottom of the contaminated groundwater along with the mixed gas, and the groundwater is repaired by the method of Example 2 as a control, and the degradation rate of VOCs is detected, with toluene as a reference. The results are shown in Table 2 below:

[0075] Table 2 VOCs degradation rate in groundwater

[0076] Group Toluene degradation rate / % Comparison 93.65

[0077] It can be seen from the results in Table 2 above that after the first hollow sphere and the second hollow sphere were not used as the release frame, the remediation effect decreased to a certain extent. Taking toluene as an example, its degradation rate dropped from 96.37% to 93.65%. It can be seen that the drug release frame formed by the first hollow sphere and the second hollow sphere can release the oxygen-releasing particles and the composite bacterial agent particles gradually, thereby improving the distribution uniformity of the oxygen-releasing particles and the composite bacterial agent particles in the groundwater to be treated, and enhancing its biodegradation treatment effect on volatile pollutants in groundwater.

[0078] At the same time, in order to verify the use effect of the repair agent prepared in different embodiments in the repair treatment, the repair agent prepared in Examples 4 to 13 is used in combination with the method of Example 2 to repair the groundwater for 30 days, and the degradation rate of VOCs is detected, with toluene as a reference. The results are shown in Table 3 below:

[0079] Table 3 VOCs degradation rate in groundwater

[0080] Group Toluene degradation rate / % Group Toluene degradation rate / % Example 4 95.29 Example 9 95.96 Example 5 94.87 Example 10 95.65 Example 6 95.66 Embodiment 11 95.79 Example 7 96.05 Example 12 95.21 Example 8 96.14 Example 13 95.43

[0081] It can be seen from the results in Table 3 above that the use of the repair agents in the above embodiments for groundwater repair treatment has a good treatment effect. Taking toluene as an example, the degradation rate is ≥92%, and the treated groundwater meets the requirements of the GB / T14848-2017 groundwater quality standard. The following exploration is now made:

[0082] 1) Effects of different oxygen-releasing particles and composite bacterial agent particle loading ratios on the use of repair agents

[0083] By comparing Example 4 and Example 5 with Example 1, it can be seen that when different masses of oxygen-releasing particles and composite bacterial agent particles are loaded in the second hollow sphere, there is a certain influence on the use effect of the prepared remediation agent. On the basis of Example 1, reducing the loading amount of the oxygen-releasing particles and the composite bacterial agent particles reduces the use effect of the remediation agent for groundwater treatment, while increasing the loading amount of the oxygen-releasing particles and the composite bacterial agent particles also reduces the use effect of the remediation agent for groundwater treatment. This may be because too high a loading amount will reduce the effect of being disturbed by water flow or air flow, thereby affecting the release effect of the oxygen-releasing particles and the composite bacterial agent particles, while too low a loading amount will significantly reduce the release persistence of the oxygen-releasing particles and the composite bacterial agent particles, so the use effect of the remediation agent is reduced. Therefore, the use effect of the remediation agent prepared by the loading amount of oxygen-releasing particles and composite bacterial agent particles in Example 1 is relatively optimal.

[0084] 2) Effect of different oxygen-releasing adhesives on the effect of repair agents

[0085] By comparing Example 6 and Example 7 with Example 1, it can be seen that the use of the oxygen-releasing colloid prepared under different ratios for the preparation of the first hollow sphere, the second hollow sphere, and the oxygen-releasing particles has a certain influence on the use effect of the prepared repair agent. On the basis of Example 1, reducing or increasing the number of each component in the oxygen-releasing colloid reduces the use effect of the repair agent for groundwater treatment. Therefore, the use effect of the repair agent prepared by the loading amount of the oxygen-releasing particles and the composite bacterial agent particles in Example 1 is relatively optimal.

[0086] At the same time, in order to verify the role of tourmaline powder in the oxygen-releasing adhesive, a control was first set up. Based on Example 1, tourmaline powder was not added to the oxygen-releasing adhesive to prepare a repair agent, and the method of Example 2 was used to repair groundwater for 30 days, and the degradation rate of VOCs was detected, with toluene as a reference. The results are shown in Table 4 below:

[0087] Table 4 VOCs degradation rate in groundwater

[0088] Group Toluene degradation rate / % Comparison 94.92

[0089] It can be seen from the results in Table 4 above that after tourmaline powder was not used as a component of the oxygen-releasing adhesive, its repair effect decreased to a certain extent. Taking toluene as an example, its degradation rate dropped from 96.37% to 94.92%. It can be seen that introducing an appropriate amount of tourmaline powder into the oxygen-releasing adhesive can not only effectively enhance the structural strength of the first hollow sphere and the second hollow sphere prepared by the oxygen-releasing adhesive, but also improve the repair treatment effect of the repair agent.

[0090] 3) Effect of different curing methods of oxygen-releasing adhesive on the effect of repair agent

[0091] By comparing Example 8 and Example 9 with Example 1, it can be seen that the first hollow spheres, the second hollow spheres, and the oxygen-releasing particles prepared by the curing method have a certain influence on the use effect of the prepared repair agent. On the basis of Example 1, lowering or increasing the bulking temperature and time will reduce the use effect of the repair agent for groundwater treatment. This may be because too low a bulking treatment affects the oxygen release effect of the subsequent oxygen-releasing material, while too high a bulking treatment affects the structural strength of the first hollow spheres and the second hollow spheres and affects the use effect of the repair agent. Therefore, the use effect of the repair agent prepared by the curing method of the oxygen-releasing glue in Example 1 is relatively optimal.

[0092] 4) Effects of different composite bacterial agent particles on the use of repair agents

[0093] By comparing Example 10 and Example 11 with Example 1, it can be seen that the composite bacterial agent particles prepared using different ratios have a certain influence on the use effect of the prepared remediation agent. On the basis of Example 1, reducing or increasing the number of components in the composite bacterial agent will reduce the use effect of the remediation agent for groundwater treatment. Therefore, the use effect of the remediation agent prepared using the composite bacterial agent particles in Example 1 is relatively optimal.

[0094] 5) Effect of different mixed bacterial powders on the effect of repair agents

[0095] By comparing Example 12 and Example 13 with Example 1, it can be seen that the preparation of composite bacterial agent particles using mixed bacterial powders in different ratios has a certain impact on the use effect of the prepared repair agent. On the basis of Example 1, reducing or increasing the proportion of each component in the mixed bacterial powder will reduce the use effect of the repair agent for groundwater treatment. Therefore, the use effect of the repair agent prepared by the mixed bacterial powder in Example 1 is relatively optimal.

Claims

1. A remediation agent for treating volatile pollutants in groundwater, characterized in that: include: A first hollow ball, a second hollow ball rotatably arranged in the first hollow ball, and oxygen-releasing particles and composite bacterial agent particles filled in the second hollow ball, the first hollow ball and the second hollow ball are both provided with a plurality of holes for docking by rotating with each other, and the oxygen-releasing particles and the composite bacterial agent particles are filled according to n[1 / 2, 3 / 2] and n[1 / 5, 1 / 2] respectively, where n is the total mass of the first hollow ball and the second hollow ball.

2. A repair agent for treating volatile pollutants in groundwater according to claim 1, characterized in that: The first hollow sphere, the second hollow sphere and the oxygen-releasing particles are all made by solidifying an oxygen-releasing adhesive in a mold.

3. A repair agent for treating volatile pollutants in groundwater according to claim 2, characterized in that: The oxygen-releasing glue solution is prepared by mixing 20 to 40 parts of gelatin and 60 to 120 parts of agar as a matrix, and adding 100 to 150 parts of calcium peroxide, 15 to 35 parts of tourmaline powder and 2 to 8 parts of sodium bicarbonate into the matrix, and mixing well to obtain the oxygen-releasing glue solution.

4. A repair agent for treating volatile pollutants in groundwater according to claim 3, characterized in that: The solidification method of the oxygen-releasing adhesive liquid is as follows: subjecting the oxygen-releasing adhesive liquid to ultrasonic treatment and continuous stirring, heating it to 45-55° C. and keeping it warm for 20-40 minutes to make the oxygen-releasing adhesive liquid expandable, then injecting it into a mold for preparing the first hollow ball, the second hollow ball or the oxygen-releasing particles, and cooling and solidifying it to obtain the first hollow ball, the second hollow ball or the oxygen-releasing particles.

5. A repair agent for treating volatile pollutants in groundwater according to claim 1, characterized in that: The second hollow ball has a partition layer which divides the interior of the second hollow ball into at least two cavities, and the cavities are respectively filled with oxygen-releasing particles or composite bacterial agent particles.

6. A repair agent for treating volatile pollutants in groundwater according to claim 1, characterized in that: The second hollow ball is provided with a counterweight block or blades for making it rotate, and the counterweight block and blades are both made by solidifying oxygen-releasing glue in a mold.

7. A repair agent for treating volatile pollutants in groundwater according to claim 1, characterized in that: The second hollow sphere is filled with oxygen-releasing particles and composite bacterial agent particles. The composite bacterial agent particles are prepared by mixing and granulating 10 to 20 parts of mixed bacterial powder, 5 to 10 parts of starch, 3 to 8 parts of diatomaceous earth, and 8 to 12 parts of water, according to mass proportions. The mixed bacterial powder is composed of Bacillus subtilis, Acinetobacter baumannii, and Rhodococcus in a mass ratio of 2 to 5:1 to 2:0.5 to 1.

8. A method for treating volatile pollutants in groundwater as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, injecting the repair agent into the bottom of the contaminated groundwater along with the mixed gas, the amount of the repair agent added is 8-13% of the mass of the contaminated groundwater; Step 2: As the mixed gas rises, some volatile pollutants in the groundwater will overflow with the mixed gas, and the gas will be collected and processed using the gas collection system. Step 3: As the mixed gas rises, the remediation agent rotates under the impetus of water flow and / or air flow, slowly releasing the oxygen-releasing particles and the composite bacterial agent particles. At the same time, the oxygen released by the remediation agent promotes the biodegradation of other volatile pollutants by indigenous microorganisms and microorganisms of the composite bacterial agent in the groundwater.

9. A method for treating volatile pollutants in groundwater using a repair agent as claimed in claim 8, characterized in that: The mixed gas is a mixed gas composed of ozone and air in a volume ratio of 1 to 2:7.

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