JP2022001363A - Method for removing toxic organic material in soil by highly efficient oxidation using composite oxidant - Google Patents

Abstract

To provide a method for removing toxic organic materials in soil by highly efficient oxidation using a composite oxidant.SOLUTION: A method for removing toxic organic materials in soil comprises: a step 1 for removing rock and other debris from collected toxic organic material soil, then polishing and breaking the soil and sifting the soil, and obtaining the sifted soil; and a step 2 for mixing at a constant ratio, the sifted soil and an oxidant A in a uniform state, then adding distilled water to the mixture, then agitating the mixture in a uniform state for obtaining slurry reaction liquid, then adding an oxidant B to the slurry reaction liquid, leaving the slurry reaction liquid at rest at a room temperature of 25-30°C for reaction, and after finish of the reaction, removing the toxic organic materials in the soil. The invention can effectively remove the toxic organic materials in the soil, has simplified processing processes and high removal efficiency, and contributes to popularization and use of restoration processing of the toxic organic material soil.SELECTED DRAWING: Figure 1

Description

The present invention relates to the technical field of soil restoration, and specifically relates to a method for removing toxic organic substances in soil by high-efficiency oxidation using a composite oxidizing agent.

Soil is an important element of the ecosystem and the basis of human survival. However, with the development of modern industry and agriculture, large amounts of waste gas, waste water and waste are improperly discharged into the soil system, causing soil pollution directly or indirectly, harming the environment and human health. There is. Polycyclic aromatic hydrocarbons (PAHs) are common high-risk organic pollutants in soil pollution. Hundreds of known PAHs have been discovered, of which many are of the utmost attention due to their "three-type lesion-inducing" effects of carcinogenicity, teratogenicity and mutagenicity.

However, current common methods of oxidizing and removing organic pollutants in soil, which usually use a single oxidant, have low removal efficiency, a narrow decomposition spectrum, and limited application conditions. Therefore, in order to solve the above technical problems, a new type of oxidation method for improving the oxidation removal efficiency of toxic organic substances in soil is required.

In order to solve the above technical problems, the present invention provides a method for removing toxic organic substances in soil by high-efficiency oxidation using a composite oxidizing agent.

The technical solution of the present invention provides a method for removing toxic organic matter in soil by highly efficient oxidation using a composite oxidant.
Step 1: Pretreatment of toxic organic contaminated soil After removing stones and other debris from the collected toxic organic contaminated soil, polish and destroy it and pass it through a 20 mesh sieve to prepare the sifted soil.
Step 2: Treatment of toxic organically contaminated soil The composite oxidant is used in combination with Agent A and Agent B. Specifically, Agent A is added to the sifted soil and sufficiently stirred to prepare a slurry. Then, agent B was added to obtain a slurry reaction solution.
The slurry reaction solution was allowed to stand at room temperature of 25 to 30 ° C. and reacted for 4 days. The persulfate ion concentration in the slurry reaction solution was 0.05 to 0.6 mol / L, and the soil-water in the slurry reaction solution. The ratio is 1: 1 to 4, and toxic organic substances in the soil can be removed after the reaction is completed.
The agent B contains persulfate ion, ferrous ion, and oxalate ion.

Further, the agent A is calcium peroxide, and in the method, the amount of the agent A added is 5 to 60 g with respect to 1 kg of soil after air drying.

Furthermore, in the above method, the amount of the agent A added is 20 to 40 g per 1 kg of soil after air drying.
Is.

Further, the agent B is persulfate ion, ferrous ion, and oxalate ion, of which the oxalate ion is added in the form of potassium oxalate, and the ferrous ion is added in the form of ferrous sulfate ion. In addition, the persulfate ion is added in the form of sodium persulfate.

Further, the concentration of persulfate ion in the slurry reaction solution is 0.2 to 0.4 mol / L.
Furthermore, the molar ratio of ferrous ion to persulfate ion is 1: 1 to 16, and the molar ratio of ferrous ion to oxalate ion is 1: 1 to 5.

Furthermore, the molar ratio of ferrous ion to oxalate ion is 1: 2, and the molar ratio of ferrous ion to persulfate ion is 1: 2.

Further, in the above method, the toxic organic contaminants typified by polycyclic aromatic hydrocarbons are naphthalene, acenaphthylene, acenaphthene, phenanthrene, anthracene, fluoranthene, pyrene, benzo [a] anthracene, chrysene, benzo [b] fluoranthene, respectively. ,
Benzo [a] pyrene, dibenzo [a, b] anthracene, benzo [g, h, i] perylene and indeno [1,2,3 to cd] pyrene.

The present invention has the following beneficial effects.
(1) The method of the present invention can repair toxic organic matter soil with a composite oxidant and effectively remove toxic organic matter in the soil, and the treatment process is simple and the removal efficiency is high, and the toxic organic matter soil is repaired. Contributes to the spread and use of.
(2) In the method of the present invention, a composite oxidant and soil to be treated are mixed to prepare a slurry reaction solution, and the composite oxidant and the slurry soil are sufficiently reacted to improve the treatment effect of toxic organically contaminated soil. be able to.

It is a schematic diagram of the whole structure of the stirring control device of this invention. It is sectional drawing of the partial structure of the stirring control device of this invention. It is a top view of the internal structure of the stirring control device of this invention.

[Explanation of sign]
1 Reaction chamber 2 Guide groove 21 Guide port 22 Control chamber 3 Base 4 Liquid storage chamber 41 Ring tube 5 Control tube 51 Electric control plug 52 Sensor 6 Stirring impeller 61 Color indicator 62 Drive motor

Example 1
A method for removing toxic organic matter in soil by high-efficiency oxidation using a composite oxidant is
Step 1: Pretreatment of toxic organic contaminated soil After removing stones and other debris from the collected toxic organic contaminated soil, polish and destroy it and pass it through a 20 mesh sieve to prepare the sifted soil.
Step 2: Treatment of toxic organically contaminated soil The composite oxidant is used in combination with Agent A and Agent B. Specifically, Agent A is added to the sifted soil and sufficiently stirred to prepare a slurry. Then, agent B was added to obtain a slurry reaction solution.
The slurry reaction solution was allowed to stand at room temperature of 27 ° C. and reacted for 4 days. The persulfate ion concentration in the slurry reaction solution was 0.2 mol / L, and the soil-water ratio in the slurry reaction solution was 1: 1. It involves removing toxic organic matter in the soil after the reaction is complete.
Among them, the amount of agent A added is 20 g / kg with respect to 1 kg of air-dried soil, agent B is persulfate ion, ferrous ion, and oxalate ion, and oxalate ion is potassium oxalate ion. Add in form, ferrous ions are added in the form of ferrous sulfate, persulfate ions are added in the form of sodium persulfate, the molar ratio of ferrous and persulfate ions is 1: 2, and the first The molar ratio of iron ion to oxalate ion is 1: 2.

Example 2
A method for removing toxic organic matter in soil by high-efficiency oxidation using a composite oxidant is
Step 1: Pretreatment of toxic organic contaminated soil After removing stones and other debris from the collected toxic organic contaminated soil, polish and destroy it and pass it through a 20 mesh sieve to prepare the sifted soil.
Step 2: Treatment of toxic organically contaminated soil The composite oxidant is used in combination with Agent A and Agent B. Specifically, Agent A is added to the sifted soil and sufficiently stirred to prepare a slurry. Then, agent B was added to obtain a slurry reaction solution.
The slurry reaction solution was allowed to stand at room temperature of 27 ° C. and reacted for 4 days. The persulfate ion concentration in the slurry reaction solution was 0.05 mol / L, and the soil-water ratio in the slurry reaction solution was 1: 1. It involves removing toxic organic matter in the soil after the reaction is complete.
Among them, the amount of agent A added is 60 g / kg with respect to 1 kg of air-dried soil, agent B is persulfate ion, ferrous ion, and oxalate ion, and oxalate ion is potassium oxalate ion. Add in form, ferrous ions are added in the form of ferrous sulfate, persulfate ions are added in the form of sodium persulfate, the molar ratio of ferrous and persulfate ions is 1: 1 and the first The molar ratio of iron ion to oxalate ion is 1: 1.

Example 3
A method for removing toxic organic matter in soil by high-efficiency oxidation using a composite oxidant is
Step 1: Pretreatment of toxic organic contaminated soil After removing stones and other debris from the collected toxic organic contaminated soil, polish and destroy it and pass it through a 20 mesh sieve to prepare the sifted soil.
Step 2: Treatment of toxic organically contaminated soil The composite oxidant is used in combination with Agent A and Agent B. Specifically, Agent A is added to the sifted soil and sufficiently stirred to prepare a slurry. Then, agent B was added to obtain a slurry reaction solution.
The slurry reaction solution was allowed to stand at room temperature of 27 ° C. and reacted for 4 days. The persulfate ion concentration in the slurry reaction solution was 0.6 mol / L, and the soil-water ratio in the slurry reaction solution was 1: 1. It involves removing toxic organic matter in the soil after the reaction is complete.
Among them, the amount of agent A added is 5 g / kg with respect to 1 kg of air-dried soil, agent B is persulfate ion, ferrous ion, and oxalate ion, and oxalate ion is potassium oxalate ion. Add in form, ferrous ions are added in the form of ferrous sulfate, persulfate ions are added in the form of sodium persulfate, the molar ratio of ferrous and persulfate ions is 1:16, first. The molar ratio of iron ion to oxalate ion is 1: 5.

Example 4
This embodiment is basically the same as that of the first embodiment, but in step 2, the reaction is stirred and controlled by the stirring control device.
As shown in FIGS. 1 to 3, the stirring control device includes a reaction chamber 1, a guide groove 2, a base 3 and a liquid storage chamber 4, the base 3 is connected to the bottom of the reaction chamber 1, and the liquid storage chamber 4 reacts. Connected to the top of the chamber 1, a guide groove 2 is fitted in the upper part of the reaction chamber 1 and extends into the reaction chamber 1 via 6 sets of guide ports 21 provided along the circumferential direction, and each guide port 21 A control chamber 22 for adding the agent B is further provided in the guide groove 2 between the two, and the guide pipe at the lower end of the control chamber 22 extends into the reaction chamber 1 and reaches the tip of the guide pipe of the control chamber 22. A control pipe 5 for controlling the salary is provided, and an electric control plug 5 for controlling the outlet of the guide pipe is provided on the inner wall of the control pipe 5.
1 is provided, a sensor 52 for recognizing the color of light rays is provided on one side of the outer wall of the control tube 5, a stirring impeller 6 is provided at the bottom of the reaction chamber 1, and the bottom of the stirring impeller 6 serves as a rotation axis. It is connected to the output shaft of the drive motor 62 fitted to the base 3 through the reaction chamber 1 through the reaction chamber 1, and one arcuate color indicator 61 is provided on the edge of each blade of the stirring impeller 6.
A water distribution device consisting of a plurality of sets of annular tubes 41 is further provided on the top surface of the reaction chamber 1, and each annular tube is connected to the liquid storage chamber 4 via a small water pump and a pipeline, of which the inside of the base 3 is provided. A controller for stirring control is further fitted in the device, the controller may be a commercially available programmable single-chip computer, and the sensor 52 for color recognition may be a commercially available keyence color recognition sensor. The color indicator 61 may be a commercially available light emitting led lamp, and the color indicator 6 of the present apparatus may be used.
The drive motor 62 may be a commercially available rotary motor as long as it is adjusted to the shape of 1. The electric control plug 51 is provided with a plug at the tip for blocking the outlet of the guide pipe. A commercially available push rod motor, the push rod motor is provided on the inner wall of the control tube 5 on the side facing the outlet of the guide pipe, and the stirring control device is powered by an external power source or an external lithium ion battery pack. It may be supplied, or a lithium ion battery pack may be fitted in the base 3 to power the device.
The operation method of step 2 by the stirring control device is as follows.
The required dose of B agent is uniformly divided into 6 sets and administered into the 6 control chambers 22, the colors of each of the 6 sets of color indicators 61 are preset, and the sensors 52 corresponding to each color are set.
Subsequently, after adding the agent A and the sifted soil and sufficiently stirring the mixture, the mixture is added into the reaction chamber 1 via each guide port 21 of the guide groove 2, and the stirring impeller 6 is rotated by the drive motor 62.
Next, water having a mass ratio of 1: 1 was added through the liquid storage chamber 4 provided at the top thereof, and the mixture was sufficiently stirred under the action of the stirring impeller 6 to obtain a slurry, and then the rotation speed of the stirring impeller 6 was increased to 10 rpm. Color indicator 6 of the blades of a set of stirring impellers 6 reduced and commanded by the controller
A sensor 52 for color recognition that displays a set of preset colors in 1 and corresponds to each time it rotates.
Triggered, the triggered sensor 52 is turned on for 3 seconds, the on period can be adjusted according to the actual need, 6 sets of B agents are added in order by the above method, and finally 6 sets of colors. The indicator 61 is turned on at the same time and rotated at 10 rpm for 3 minutes or more to ensure the addition of the B agent into the control chamber 22, and the number of control sets is controlled by a plurality of sets at the same time as necessary. May go and improve salary, agitation and reaction control.

Example 5
This example is basically the same as the principle of Example 1 except for the following, and the mixing method with the components of the composite oxidant and the soil to be treated is different.
Step 1: Pretreatment of toxic organic matter soil After removing debris such as stones from the collected toxic organic matter soil, polish and destroy it and let it pass through a 30 mesh sieve to prepare the sifted soil.
Step 2: Preparation of slurry reaction solution The above-sieved soil and the improved composite oxidant are uniformly mixed at a mass ratio of 1: 3 at a ratio of 1/3 of the total mass, and then uniformly mixed. Add 45% of the total volume of distilled water to the product.
Includes uniform stirring to obtain a slurry reaction solution.
Among them, the improved composite oxidant consists of agent A and agent B. Specifically, agent A and the sifted soil are sufficiently stirred, and then agent B is added, and agent A is calcium peroxide and hydroxy. A mixture of ethyl cellulose with calcium peroxide and hydroxyethyl cellulose at 7: 0.5.
B agent is a mixture of oxalate ion, ferrous ion, persulfate ion and acetate ion, and oxalate ion, ferrous ion, persulfate ion and acetate ion are 3: 2: 2: Mixed in a molar ratio of 16: 4, oxalate ions were added in the form of potassium oxalate and added.
Iron ferrous ion is added in the form of ferrous sulfate, persulfate ion is added in the form of sodium persulfate, ion is acetate and added in the form of sodium acetate, and the above potassium oxalate, ferrous sulfate, etc. are used. In order to add the corresponding ion, the difficulty of acquisition is low, the construction cost is low, and a large amount of toxic organic soil can be batch-processed at low cost, which contributes to mass dissemination and use.
Step 3: Treatment of toxic organic matter soil The above slurry reaction solution and the remaining sieved soil are thoroughly mixed and stirred at temperature 2
Spray the reaction aid at 7 ° C., spray at 160 ml / min for 3 minutes prior to stirring, then adjust to 55 ml / min, reduce at a rate of 5 ml / min until spraying is complete, and after stirring for 12 minutes. , Stirring can be stopped, placed in the dark for reaction, and after the reaction is complete, toxic organic matter in the soil can be removed.
Among them, the reaction auxiliary liquid is a mixed liquid formed by mixing a compound oxidizing agent B agent and a certain amount of distilled water, and the mass concentration of the B agent in the mixed liquid is 5.5%.

Example 6
This Example is basically the same as Example 1, but the mass of the soil sifted for preparing the slurry reaction solution together with the complex oxidant is different, specifically.
The above-sieved soil and the composite oxidant are collected at a ratio of 1/6 of the total mass and mixed uniformly.

Example 7
This Example is basically the same as Example 1, but the mass of the soil sifted for preparing the slurry reaction solution together with the complex oxidant is different, specifically.
Collect the sifted soil and the composite oxidant at a ratio of 1/2 of the total mass and mix them uniformly.

Example 8
This Example is basically the same as Example 1, but the ratio of the A agent of the composite oxidant is different. Specifically, the A agent is a mixture of calcium peroxide and hydroxyethyl cellulose, and is different from calcium peroxide. Hydroxyethyl cellulose is mixed in a mass ratio of 7: 0.2.

Example 9
This Example is basically the same as Example 1, but the ratio of the A agent of the composite oxidant is different. Specifically, the A agent is a mixture of calcium peroxide and hydroxyethyl cellulose, and is different from calcium peroxide. Hydroxyethyl cellulose is mixed in a mass ratio of 7: 1.

Example 10
This Example is basically the same as Example 1, but the ratio of the B agent of the composite oxidizing agent is different, and specifically, the B agent is a oxalate ion, a ferrous ion, a persulfate ion and an acetate ion. It is a mixture of oxalate ion, ferrous ion, persulfate ion and acetate ion 1: 2: 18 :.
Mix at a molar ratio of 5.

Example 11
This Example is basically the same as Example 1, but the ratio of the B agent of the composite oxidizing agent is different, and specifically, the B agent is a oxalate ion, a ferrous ion, a persulfate ion and an acetate ion. It is a mixture of oxalate ion, ferrous ion, persulfate ion and acetate ion 5: 2: 3: 3.
Mix in a molar ratio of.

Example 12
This example is basically the same as that of Example 1, but the mass concentration of the B agent in the reaction auxiliary liquid is different, and specifically, the mass concentration of the B agent in the mixed liquid is 3%.

Example 13
This example is basically the same as that of Example 1, but the mass concentration of the B agent in the reaction auxiliary liquid is different, and specifically, the mass concentration of the B agent in the mixed liquid is 8%.

Example 14
This example is basically the same as that of Example 1, but the spray temperature of the reaction auxiliary liquid is different. Specifically, the reaction auxiliary liquid of 20 ° C. is sprayed during the stirring period.

Example 15
This example is basically the same as that of Example 1, but the spray temperature of the reaction auxiliary liquid is different. Specifically, the reaction auxiliary liquid having a temperature of 35 ° C. is sprayed during the stirring period.

Example 16
This Example is basically the same as Example 1, but the spray dose of the reaction aid is different, specifically, spray at 120 ml / min for 3 minutes before stirring, then 35 ml / min. Adjust and spray, then reduce at a rate of 5 ml / min by the end of the spray, stir for 12 minutes, then stop stirring and place in the dark for reaction.

Example 17
This Example is basically the same as Example 1, but the spray dose of the reaction aid is different, specifically, spray at 180 ml / min for 3 minutes before stirring, then 60 ml / min. Adjust and spray, then reduce at a rate of 5 ml / min by the end of the spray, stir for 12 minutes, then stop stirring and place in the dark for reaction.

Example 18
This example is basically the same as that of Example 1, but the addition ratio of distilled water in the slurry reaction solution is different. Specifically, 30% of the total volume of the uniformly mixed product is added with distilled water. did.

Example 19
This example is basically the same as that of Example 1, but the addition ratio of distilled water in the slurry reaction solution is different. Specifically, 50% of the total volume of the uniformly mixed product is added with distilled water. did.

試験結論：以上の表から分かるように、本方法の実施例１〜３は、すべて有毒有機汚染土
壌中の多環芳香族炭化水素を効果的に除去でき、除去効率が高い。 Experimental Study on Restoration of Toxic Organic Soil Test 1:
Preparation of test sample:
When the effect of the above method on the restoration treatment of toxic organic substances on soil was investigated, the soil of the farmland in this city was selected as a test sample, the air-dried soil was thoroughly polished and mixed uniformly, and then in the sample soil. Anthracene solution of 14 kinds of polycyclic aromatic hydrocarbons is added to the mixture, mixed sufficiently uniformly, and after the acetone is completely volatilized, the soil is aged for more than half a year, and 14 kinds of polycyclic aromatic hydrocarbons, naphthalene. , Asenaftylene, Asenaften, Pyrene, Anthracene, Fluoranthene, Pyrene, Benzo [a] Anthracene, Chrysen, Benzo [b] Fluoranten, Benzo [a] Pyrene, Dibenzo [a, b] Anthracene, Benzo [g, h, i] Perylene , Indeno [1,2,3 to cd] Pyrene content is 3.212, 0.784, 0, respectively
.. 595, 2.516, 4.986, 5.326, 7.329, 17.235, 19.3
36, 9.903, 17.512, 14.201, 26.098, 12.745 mg / k
The total content of polycyclic aromatic hydrocarbons is 141.778 mg / kg.
Exam grouping:
Using Examples 1 to 3 respectively, the sample soil of the same mass described above was repaired by HPLC / UV to FLD analysis, and as the HPLC / UV to FLD analysis conditions, the chromatography column was Ф analysis conditions: 250 mm Intersil ODS. -A reverse phase chromatography column dedicated to PAHs, the mobile phase is methanol-water, gradient elution and ultraviolet light.
PAHs are separated by the method of series connection of fluorescence detectors. Both UV and fluorescence detection employ wavelength switching, and the UV detector turns on dual wavelength detection mode. The flow rate of the mobile phase was 1.0 mL / min, the column temperature was 40 ° C., the injection amount was 20 samples, and the removal rate of polycyclic aromatic hydrocarbons in the soil after each restoration was measured.
Test results: The removal rates of 14 types of polycyclic aromatic hydrocarbons in the soil were measured, and the test results are shown in Table 1.
Table 1 Removal rate of 14 types of polycyclic aromatic hydrocarbons in toxic organic polluted soil

Test conclusion: As can be seen from the above table, all of Examples 1 to 3 of this method can effectively remove polycyclic aromatic hydrocarbons in toxic organic polluted soil, and the removal efficiency is high.

試験結論：以上の表から分かるように、上記装置の攪拌・混合により、Ｂ剤の添加を制御
して、スラリー反応液の混合均一性を高め、多環芳香族炭化水素の除去効果を向上させる
。 Test 2:
In Example 4, the apparatus used for the method of Example 1 is provided, the removal efficiency thereof is studied, the measurement work amount is taken into consideration by the same test method as described above, and seven kinds of polycycles thereof are used. The removal rate of aromatic hydrocarbons was measured, and the measurement results are as follows.
Table 2 Example 2 Comparison table of removal rates of polycyclic aromatic hydrocarbons in toxic organic polluted soil

Test conclusion: As can be seen from the above table, the addition of agent B is controlled by stirring and mixing of the above device to improve the mixing uniformity of the slurry reaction solution and improve the effect of removing polycyclic aromatic hydrocarbons. ..

結論：上記実施例５と実施例１の比較から分かるように、酸化剤成分および混合方式など
が異なると土壌修復効果に対して一定の影響を与え、そのうちに本発明の改良された複合
酸化剤の処理効果がより好ましい。 Exam 3:
In Examples 5 to 19, an optimized improved treatment method based on the method of Example 1 is provided, the removal efficiency thereof is studied, and the measurement work amount is taken into consideration by the same test method as described above. The removal rates of the seven types of polycyclic aromatic hydrocarbons were measured, and the measurement results are as follows.
1) Study on the repair effect of the improved composite oxidant Table 3 shows the test results in experimental contrast with Example 1.
Table 3 Control example with Example 5 Comparison table of removal rate of polycyclic aromatic hydrocarbons

Conclusion: As can be seen from the comparison between Example 5 and Example 1, different oxidant components, mixing methods, etc. have a certain effect on the soil repair effect, and the improved composite oxidant of the present invention is used. The treatment effect of is more preferable.

結論：上記実施例６、７と実施例５の比較から分かるように、スラリー反応溶液の比率が
異なると、修復効果に対して影響を与え、そのうちに実施例５の処理効果がより好ましい
。 2) Research on the effect of different ratios of slurry reaction solutions on the repair effect In Examples 6 and 7, soil treatment tests were conducted, respectively, and compared with Example 3, the test results are shown in Table 4.
Shown in.
Table 4 Examples 6 and 7 Comparison table of removal rates of polycyclic aromatic hydrocarbons

Conclusion: As can be seen from the comparison between Examples 6 and 7 and Example 5, different ratios of the slurry reaction solutions affect the repair effect, and the treatment effect of Example 5 is more preferable.

結論：上記実施例８、９と実施例５の比較から分かるように、Ａ剤の配合比率が異なると
土壌修復に対して一定の影響を与え、そのうちに実施例５の処理効果がより好ましい。 3) Research on the effect of agents A in different ratios on the repair effect In Examples 8 and 9, soil treatment tests were conducted, respectively, and compared with Example 3, the test results are shown in Table 5.
Shown in.
Table 5 Example 8 and 9 Comparison table of removal rates of polycyclic aromatic hydrocarbons

Conclusion: As can be seen from the comparison between Examples 8 and 9 and Example 5, different blending ratios of Agent A have a certain effect on soil repair, and the treatment effect of Example 5 is more preferable.

結論：上記実施例１０、１１と実施例５の比較から分かるように、Ｂ剤の配合比率が異な
ると土壌修復に対して一定の影響を与え、そのうちに実施例５の処理効果がより好ましい
。 4) Study on the effect of agents B in different ratios on the repair effect In Examples 10 and 11, soil treatment tests were conducted, respectively, and compared with Example 5, the test results are shown in Table 6.
Table 6 Comparison table of removal rates of polycyclic aromatic hydrocarbons in Examples 8 and 9.

Conclusion: As can be seen from the comparison between Examples 10 and 11 and Example 5, different blending ratios of Agent B have a certain effect on soil repair, and the treatment effect of Example 5 is more preferable.

結論：上記実施例１２、１３と実施例５の比較から分かるように、反応補助液の比率が異
なると、土壌修復に対して一定の影響を与え、そのうちに実施例５の処理効果がより好ま
しい。 5) Study of the effect of different ratios of reaction aids on the repair effect In Examples 12 and 13, the soil treatment test was compared with the following Example 5, and the test results are shown in Table 7.
Shown in.
Table 7 Comparison table of removal rates of polycyclic aromatic hydrocarbons in Examples 10 and 11

Conclusion: As can be seen from the comparison between Examples 12 and 13 and Example 5, different ratios of the reaction aids have a certain effect on soil repair, and the treatment effect of Example 5 is more preferable. ..

結論：上記実施例１４、１５と実施例５の比較から分かるように、反応補助液の温度が異
なると土壌修復に対して一定の影響を与え、そのうちに実施例５の処理効果がより好まし
い。 6) Study on the effect of different reaction aids on the temperature repair effect In Examples 14 and 15, soil treatment tests were conducted, respectively, and compared with Example 5, the test results are shown in Table 8.
Table 8 Comparison table of removal rates of polycyclic aromatic hydrocarbons in Examples 12 and 13.

Conclusion: As can be seen from the comparison between Examples 14 and 15 and Example 5, different temperatures of the reaction aids have a certain effect on soil repair, and the treatment effect of Example 5 is more preferable.

結論：上記実施例１６、１７と実施例５の比較から分かるように、反応補助液のスプレー
量が異なると土壌修復に対して一定の影響を与え、そのうちに実施例５の処理効果がより
好ましい。 7) Study on the effect of different spray amounts of reaction aids on the repair effect In Examples 16 and 17, soil treatment tests were conducted, respectively, and compared with Example 5, the test results are shown in Table 9.
Table 9 Examples 16 and 17 Comparison table of removal rates of polycyclic aromatic hydrocarbons

Conclusion: As can be seen from the comparison between Examples 16 and 17 and Example 5, different spray amounts of the reaction auxiliary liquid have a certain effect on soil repair, and the treatment effect of Example 5 is more preferable. ..

結論：上記実施例１８、１９と実施例５の比較から分かるように、スラリー反応溶液の水
希釈度が異なると土壌修復に対する影響が小さく、そのうちに実施例５の処理効果がより
好ましい。 8) Study on the effect of different slurry reaction solutions on the repair effect of water dilution In Examples 18 and 19, soil treatment tests were performed, respectively, and compared with Example 5, the test results are shown in Table 10.
Table 10 Examples 18 and 19 Comparison table of removal rates of polycyclic aromatic hydrocarbons

Conclusion: As can be seen from the comparison between Examples 18 and 19 and Example 5, the effect on soil repair is small when the water dilution of the slurry reaction solution is different, and the treatment effect of Example 5 is more preferable.

Claims (7)

Step 1: Pretreatment of toxic organic contaminated soil After removing stones and other debris from the collected toxic organic contaminated soil, grind and destroy it and let it pass through a 20 mesh sieve to prepare the sifted soil.
Step 2: Treatment of toxic organically contaminated soil The compound oxidizing agent is used in combination with agent A and agent B, and agent A is added to the sifted soil and stirred to prepare a slurry, and agent B is added to the slurry. Obtain a reaction solution, and use 2 of the slurry reaction solution.
The mixture was allowed to stand at room temperature of 5 to 30 ° C. for 4 days, and the concentration of persulfate ion in the slurry reaction solution was 0.
It is 05 to 0.6 mol / L, the soil-water ratio in the slurry reaction solution is 1: 1 to 4, and after the reaction is completed, toxic organic substances in the soil are removed, and the agent B is persulfate ion. , Ferrite ion, oxalate ion, and
A method for removing toxic organic matter in soil by high-efficiency oxidation using a composite oxidizing agent, which comprises. The agent A is calcium peroxide, and in the method according to claim 1, the soil 1k after air-drying.
The method according to claim 1, wherein the amount of the agent A added is 5 to 60 g with respect to g. In the method according to claim 1, the amount of agent A added is 20 to 4 with respect to 1 kg of soil after air drying.
The method according to claim 2, wherein the weight is 0 g. The agent B is persulfate ion, ferrous ion, and oxalate ion.
Claim 1 is characterized in that the oxalate ion is added in the form of potassium oxalate, the ferrous ion is added in the form of ferrous sulfate, and the persulfate ion is added in the form of sodium persulfate.
The method described in. The method according to claim 1, wherein the concentration of persulfate ion in the slurry reaction solution is 0.2 to 0.4 mol / L. The fifth aspect of claim 5, wherein the molar ratio of ferrous ion to persulfate ion is 1: 1 to 16, and the molar ratio of ferrous ion to oxalate ion is 1: 1 to 5. The method described. In the method according to claim 1, the toxic organic contaminants represented by polycyclic aromatic hydrocarbons are naphthalene, acenaphtylene, acenaphthalene, phenanthrene, anthracene, fluorantene, pyrene, benzo [a] anthracene, chrysen, and benzo, respectively. [B] Fluorentene, benzo [a] pyrene, dibenzo [a, b] anthracene, benzo [g, h, i] perylene and indeno [1,2,3 to cd] pyrene. The method according to 1.

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