CN214611726U - PRB construction system for repairing polluted underground water - Google Patents
PRB construction system for repairing polluted underground water Download PDFInfo
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- CN214611726U CN214611726U CN202022418153.1U CN202022418153U CN214611726U CN 214611726 U CN214611726 U CN 214611726U CN 202022418153 U CN202022418153 U CN 202022418153U CN 214611726 U CN214611726 U CN 214611726U
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Abstract
The utility model belongs to the environmental protection field, concretely relates to a PRB construction system for repairing pollute groundwater. This PRB construction system includes: the injection well group comprises a plurality of injection wells, and is arranged in a downstream area of the flow direction of the underground water in the pollution area and on a pollution boundary of the downstream area; the monitoring well group comprises a plurality of monitoring wells and is arranged around the periphery of the injection well group; the automatic medicament dosing system is used for automatically dosing medicaments into the injection well; the detection system is used for monitoring pollution indexes of underground water; and the injection well group and the monitoring well group form a PRB wall system. The PRB construction system can complete the whole process of in-situ remediation of polluted underground water, and has the advantages of simple structure, convenience in construction, low cost and good application prospect.
Description
Technical Field
The utility model belongs to the environmental protection field, more specifically relates to a PRB construction system for repairing pollute groundwater.
Background
The heavy metal chromium, as an industrial raw material, has certain influence on the environment in long-term production and application. Chromium exists in soil mainly in two valence states of trivalent chromium (Cr (III)) and hexavalent chromium (Cr (VI)). Wherein Cr (III) is a trace element necessary for human bodies, shows biotoxicity only under a higher concentration, can form stable hydroxide within the pH range of 6-11, exists in a precipitate form, and has weak migration capacity; cr (VI) has strong carcinogenic effect, high solubility in water and strong migration ability.
Hexavalent chromium has a strong oxidizing property, is a highly toxic mutagenic, carcinogenic agent, and is generally considered to be 100 times more toxic than trivalent chromium. The chromium-containing wastewater enters a water body, which can endanger the growth of aquatic animals and plants, influence aquaculture and cause great reduction of yield and even fish and shrimp sterilization; destruction of farmland soil, destruction of crops and damage to human health through food chains; when entering the drinking water source, the patient may suffer chronic poisoning due to accumulation of light substances in the human body and death due to serious substances. Hexavalent chromium is mainly chronic toxic to humans, and it can invade the human body through the digestive tract, respiratory tract, skin and mucous membrane, accumulating in the body mainly in the liver, kidney and endocrine glands.
The underground water is a valuable fresh water resource for human beings and also a material basis for sustainable development of society. However, the current problem of groundwater pollution caused by human activities is becoming serious, and the ecological environment and the human health are threatened.
At present, the treatment methods commonly adopted at home and abroad aiming at the hexavalent chromium pollution of underground water are mainly divided into the traditional extraction treatment and in-situ remediation methods. The pumping treatment method is to pump the polluted underground water by a water pump at the downstream of the polluted underground water, remove the pollutants in the waste water by ground treatment facilities and methods to reach the treatment standard, and then discharge the waste water into the nature or recycle the waste water. Pumping treatment needs to be carried out on a large amount of water, a large amount of pumping wells are generally required to be arranged in a restoration area, and if a site does not have well building conditions, construction of underground water restoration is affected; the pumping treatment of a large amount of sewage increases the cost of repair construction, and causes the problem of secondary discharge of a large amount of wastewater; in addition, the extraction of a large amount of sewage will affect the surrounding hydrogeological conditions and the surrounding structures.
Therefore, in order to solve the above problems and prevent groundwater influence, a hexavalent chromium contaminated groundwater remediation process requires a special in-situ treatment technique.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a PRB construction system for restoreing pollute groundwater, this PRB construction system not only can accomplish and pollute the prosthetic overall process of groundwater normal position, and simple structure, and construction convenience, it is with low costs, have better application prospect.
In order to achieve the above object, the utility model provides a PRB construction system for repairing pollute groundwater, this PRB construction system includes:
the injection well group comprises a plurality of injection wells, and is arranged in a downstream area of the flow direction of the underground water in the pollution area and on a pollution boundary of the downstream area; the number of the injection wells is not less than 1/500-1/300 of the area of a pollution area, and the distance between each injection well and another injection well which is closest to the injection well is 20-40 m;
the monitoring well group comprises a plurality of monitoring wells, the monitoring wells are arranged around the periphery of the injection well group, the number of the monitoring wells is not less than 1/900-1/700 of the area of a pollution area, and the distance between each monitoring well and another monitoring well which is closest to the monitoring well is 60-100 m;
the automatic medicament dosing system is used for automatically dosing medicaments into the injection well;
the monitoring system is used for monitoring pollution indexes of underground water;
and the injection well group and the monitoring well group form a PRB wall system.
Preferably, the filling material is filled between the injection wells and is zeolite.
Preferably, the filling amount of the zeolite is 1/120-1/80 of the amount of the polluted underground water.
Preferably, the injection well comprises:
the cement platform is arranged on the ground;
the injection well pipe penetrates through the cement platform, the upper part of the injection well pipe is a solid pipe, and the lower part of the injection well pipe is a sieve pipe;
the quick connector is arranged at the top of the injection well pipe;
and the well bottom seal is arranged at the bottom of the injection well pipe.
Preferably, the solid pipe periphery is provided with cement and bentonite from top to bottom, the screen pipe periphery is provided with quartz sand.
Preferably, the depth of the injection well is 0.5-1.5 m below the depth of the polluted underground water.
Preferably, the monitoring well comprises:
the monitoring well pipe comprises a monitoring well pipe, a solid pipe and a perforated pipe, wherein the upper part of the monitoring well pipe is provided with the solid pipe, and the lower part of the monitoring well pipe is provided with the perforated pipe;
the protective sleeve is sleeved outside the top monitoring well pipe;
the concrete seal is positioned outside the upper monitoring well pipe, part of the concrete seal is positioned above the ground, and the other part of the concrete seal is positioned below the ground;
and the bottom sealing cover is arranged at the bottom of the monitoring well pipe.
Preferably, the periphery of the lower part of the solid pipe is provided with a plugging material; and graded cobble fillers are arranged on the periphery of the perforated pipe.
Preferably, the material of the monitoring well pipe is HDPE.
Preferably, the depth of the monitoring well is 0.5-1.5 m below the depth of the polluted underground water.
Compared with the prior art, the utility model discloses possess following advantage:
1. the utility model discloses a PRB construction system is mainly to inject well group and monitoring well group, and system structure is simple, and construction convenience effectively reduces the restoration cost, and the utility model relates to an injection well, monitoring well etc. all are common facility materials in the environmental remediation engineering, and the construction is simple, the low price, and construction material can be bought nearby, effectively shortens construction period; the in-situ repair system has a fast construction period and does not influence the construction progress.
2. The utility model discloses use PRB construction system to handle and pollute groundwater, effectively avoid taking out of a large amount of offal to handle, reduced energy consumption and cost, avoid secondary pollution, safety, clean, environmental benefit is obvious.
3. The utility model has wide application range, can be used for in-situ remediation of polluted underground water such as hexavalent chromium, heavy metals, metalloids, petroleum hydrocarbons, semi-volatile organic compounds and the like, and has strong applicability, safety and stability; injection well and monitoring well can carry out reasonable adjustment according to area of pollution and pollutant concentration, and the handling capacity in normal position reaction zone is big, and the repair cost is low, and engineering applicability is strong.
Other features and advantages of the present invention will be described in detail in the detailed description which follows.
Drawings
The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout the exemplary embodiments of the present invention.
Fig. 1 shows a schematic distribution diagram of a PRB construction system according to a specific embodiment of the present invention;
fig. 2 shows a PRB construction system process flow diagram according to a specific embodiment of the present invention;
fig. 3 shows a schematic injection well structure of a PRB construction system according to a specific embodiment of the invention;
fig. 4 shows the monitoring well structure diagram of a PRB construction system according to a specific embodiment of the present invention.
Description of reference numerals:
1. a ground surface; 2. a cement platform; 3. a quick coupling; 4. solid tubes; 5. cement; 6. bentonite; 7. quartz sand; 8. a screen pipe; 9. sealing the well bottom; 10. capping the concrete; 11. monitoring a well tubular; 12. bentonite; 13. pebbles; 14. a plastic ring; 15. perforating a pipe; 16. sealing the bottom cover; 17. protecting the sleeve; 18. an injection well; 19. detecting a well; 20. automatic medicine dosing system.
Detailed Description
Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein.
The utility model provides a PRB construction system for repairing pollute groundwater, this PRB construction system includes:
the injection well group comprises a plurality of injection wells, and is arranged in a downstream area of the flow direction of the underground water in the pollution area and on a pollution boundary of the downstream area; the number of the injection wells is not less than 1/500-1/300 of the area of a pollution area, and the distance between each injection well and another injection well which is closest to the injection well is 20-40 m;
the monitoring well group comprises a plurality of monitoring wells, the monitoring wells are arranged around the periphery of the injection well group, the number of the monitoring wells is not less than 1/900-1/700 of the area of a pollution area, and the distance between each monitoring well and another monitoring well which is closest to the monitoring well is 60-100 m;
the automatic medicament dosing system is used for automatically dosing medicaments into the injection well;
the detection system is used for monitoring pollution indexes of underground water;
and the injection well group and the monitoring well group form a PRB wall system.
The utility model discloses in, utilize injection well crowd and detection well crowd to replace traditional PRB wall system, realize that the normal position of groundwater is restoreed, preferably, it packs to be filled with the filler between the injection well, the filler is zeolite, further preferably, zeolite packing prescription volume does pollute 1/120 ~ 1/80 of groundwater prescription volume.
The utility model discloses in, the injection well that adopts in the injection well crowd is the injection well of the conventional setting in this field, and this injection well generally includes but not limited to:
the cement platform is arranged on the ground;
the injection well pipe penetrates through the cement platform, the upper part of the injection well pipe is a solid pipe, and the lower part of the injection well pipe is a sieve pipe;
the quick connector is arranged at the top of the injection well pipe;
and the well bottom seal is arranged at the bottom of the injection well pipe.
Preferably, the depth of the injection well is 0.5-1.5 m below the depth of the polluted underground water.
Preferably, the solid pipe periphery is provided with cement and bentonite from top to bottom, the screen pipe periphery is provided with quartz sand.
The utility model discloses in, the monitoring well that adopts in the monitoring well crowd is also similar with the injection well, for the monitoring well of the conventional adoption of technical personnel in the field, this monitoring well generally includes but not limited to:
the monitoring well pipe comprises a monitoring well pipe, a solid pipe and a perforated pipe, wherein the upper part of the monitoring well pipe is provided with the solid pipe, and the lower part of the monitoring well pipe is provided with the perforated pipe;
the protective sleeve is sleeved outside the top monitoring well pipe;
the concrete seal is positioned outside the upper monitoring well pipe, part of the concrete seal is positioned above the ground, and the other part of the concrete seal is positioned below the ground;
and the bottom sealing cover is arranged at the bottom of the monitoring well pipe.
Preferably, the periphery of the lower part of the solid pipe is provided with a plugging material; and graded cobble fillers are arranged on the periphery of the perforated pipe.
Preferably, the material of the monitoring well pipe is HDPE.
Preferably, the depth of the monitoring well is 0.5-1.5 m below the depth of the polluted underground water.
The concrete structure of the injection well and the detection well has no special requirements in the utility model, and the technical personnel in the field can design or adjust according to the actual situation of the polluted site by themselves.
Example 1
A PRB construction system (as shown in fig. 1) for remediation of contaminated groundwater comprising: injection well group, monitoring well group, automatic medicament injection system and detection system. The injection well group and the monitoring well group form a PRB wall system, and the automatic medicament injection system is used for automatically injecting medicaments into the injection well; the detection system is used for monitoring pollution indexes of underground water.
The injection well group comprises a plurality of injection wells (shown in figure 3), the injection wells are arranged in a downstream area of the flow direction of the underground water in the polluted area and on a polluted boundary of the downstream area, the depth of the injection wells is 0.5-1.5 m below the depth of the polluted underground water, zeolite is filled between the injection wells, and the filling amount of the zeolite is 1/120-1/80 of the amount of the polluted underground water; the number of the injection wells is not less than 1/500-1/300 of the area of the pollution area, and the distance between each injection well and another injection well which is closest to the injection well is 20-40 m.
The injection well comprises: cement platform 1, injection well casing, quick connector 3 and bottom seal 9. And the cement platform 2 is arranged on the ground. The injection well pipe penetrates through the cement platform, the upper part is a solid pipe 4, the lower part is a sieve pipe 8, cement 5 and bentonite 6 are arranged on the periphery of the solid pipe from top to bottom, and quartz sand 7 is arranged on the periphery of the sieve pipe. The quick coupling 3 is arranged on top of the injection well pipe. The bottom seal 9 is arranged at the bottom of the injection well pipe.
The monitoring well group comprises a plurality of monitoring wells (shown in figure 4), the monitoring wells are arranged around the periphery of the injection well group, the number of the monitoring wells is not less than 1/900-1/700 of the area of a pollution area, and the distance between each monitoring well and another monitoring well which is closest to the monitoring well is 60-100 m.
The monitoring well includes: HDPE monitoring well pipe 11, protective sleeve 17 with diameter of 150cm, concrete top sealing 10 and bottom sealing cover 16. The depth of the HDPE monitoring well pipe 11 is 0.5-1.5 m below the depth of the polluted underground water, the upper part of the monitoring well pipe is a solid pipe, the lower part of the monitoring well pipe is a perforated pipe 15, the periphery of the lower part of the solid pipe is provided with a plugging material, and the periphery of the perforated pipe is provided with graded pebbles 13. A protective sleeve 17 is sleeved outside the top monitoring well pipe. The concrete caps are located outside the upper monitoring well pipe, part of the concrete caps 10 are located above the ground, and the other part of the concrete caps 10 are located below the ground. A bottom plug 16 is provided at the bottom of the monitoring well pipe.
The flow chart of repairing hexavalent chromium polluted groundwater by using the PRB construction system is shown in FIG. 2, and specifically comprises the following steps:
1. early preparation: a pilot test method is adopted to simulate the overall influence of local hydrogeological conditions on a PRB system and monitor the removal effect of a reducing agent on target pollutants;
2. designing an injection well group: and designing an injection well group according to the pollution range and the pollution depth, wherein the injection well group comprises the number of injection wells, the distribution of the injection wells and the depth of the injection wells.
3. And (3) construction of injection well groups: and (4) establishing injection wells according to the designed number, distribution and depth of the injection wells. Three different drilling methods may be used to install the well in situ, including ultrasonic, core auger, and push-through (Geoprobe) methods.
4. Monitoring well group construction: and designing a monitoring well group according to the pollution range and the pollution depth, wherein the monitoring well group comprises the number of monitoring wells, the distribution of the monitoring wells and the depth of the monitoring wells.
5. Filling zeolite filler.
6. Selecting an injection agent: the reduction reagent sodium dithionite is selected as a main reduction reagent, potassium carbonate is used as a pH buffer solution, and the stability of the sodium dithionite is mainly improved in the iron reduction process.
7. Injecting: selecting the injection concentration of the reducing agent according to the concentration of the pollutants, adding the reducing agent in an amount which is 5-10 times of the theoretical addition amount, and injecting the reducing agent in two batches in total, wherein half of the reducing agent is injected each time, and the interval period is one week;
and (3) the concentration of the injected medicament, wherein the injection concentration of the reducing agent is selected according to the concentration of the pollutants and is added in an amount which is 5-10 times of the theoretical addition amount.
8. Monitoring: the monitoring is started 3 days after the first batch of reducing agent is injected, and the monitoring indexes are sodium hydrosulfite and hexavalent chromium. Monitoring the second batch of reducing agent after injecting for 3-5 days, wherein the monitoring index is unchanged. If the index exceeds the standard, the step 7 is continued.
9. And (3) long-term monitoring: and after the concentration of the hexavalent chromium is monitored to reach the restoration target value, long-term monitoring is continued, the monitoring index is hexavalent chromium, and the monitoring age limit is 3 years.
While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.
Claims (10)
1. A PRB construction system for remediating contaminated groundwater, the system comprising:
the injection well group comprises a plurality of injection wells, and is arranged in a downstream area of the flow direction of the underground water in the pollution area and on a pollution boundary of the downstream area; the number of the injection wells is not less than 1/500-1/300 of the area of a pollution area, and the distance between each injection well and another injection well which is closest to the injection well is 20-40 m;
the monitoring well group comprises a plurality of monitoring wells, the monitoring wells are arranged around the periphery of the injection well group, the number of the monitoring wells is not less than 1/900-1/700 of the area of a pollution area, and the distance between each monitoring well and another monitoring well which is closest to the monitoring well is 60-100 m;
the automatic medicament dosing system is used for automatically dosing medicaments into the injection well;
the monitoring system is used for monitoring pollution indexes of underground water;
and the injection well group and the monitoring well group form a PRB wall system.
2. The PRB construction system of claim 1 wherein the injection wells are packed with a filler between them, the filler being zeolite.
3. The PRB construction system according to claim 2, wherein the zeolite fill volume is 1/120-1/80 of the contaminated groundwater volume.
4. The PRB construction system of claim 1, wherein the injection well comprises:
the cement platform is arranged on the ground;
the injection well pipe penetrates through the cement platform, the upper part of the injection well pipe is a solid pipe, and the lower part of the injection well pipe is a sieve pipe;
the quick connector is arranged at the top of the injection well pipe;
and the well bottom seal is arranged at the bottom of the injection well pipe.
5. The PRB construction system according to claim 4, wherein the solid pipe is provided with cement and bentonite from top to bottom on the outer periphery, and the sieve pipe is provided with quartz sand on the outer periphery.
6. The PRB construction system of any of claims 4-5, wherein the injection well has a depth of 0.5-1.5 m below the contaminated groundwater depth.
7. The PRB construction system of claim 1, wherein the monitoring well comprises:
the monitoring well pipe comprises a monitoring well pipe, a solid pipe and a perforated pipe, wherein the upper part of the monitoring well pipe is provided with the solid pipe, and the lower part of the monitoring well pipe is provided with the perforated pipe;
the protective sleeve is sleeved outside the top monitoring well pipe;
the concrete seal is positioned outside the upper monitoring well pipe, part of the concrete seal is positioned above the ground, and the other part of the concrete seal is positioned below the ground;
and the bottom sealing cover is arranged at the bottom of the monitoring well pipe.
8. The PRB construction system of claim 7 wherein an outer circumference of a lower portion of the solid pipe is provided with a plugging material; and graded cobble fillers are arranged on the periphery of the perforated pipe.
9. The PRB construction system of claim 7, wherein the monitoring well pipe is made of HDPE.
10. The PRB construction system of any of claims 7-9, wherein the depth of the monitoring well is 0.5-1.5 m below the depth of the contaminated groundwater.
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| CN202022418153.1U CN214611726U (en) | 2020-10-27 | 2020-10-27 | PRB construction system for repairing polluted underground water |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014504A (en) * | 2021-12-02 | 2022-02-08 | 江苏省环境科学研究院 | Biological/ultrasonic enhanced adsorption removal system for nitrate pollution of underground water and application thereof |
| CN115259442A (en) * | 2022-07-08 | 2022-11-01 | 广西壮族自治区环境保护科学研究院 | Remediation method for heavy metal chromium-organic solvent composite polluted groundwater |
| CN116274312A (en) * | 2022-10-17 | 2023-06-23 | 中国科学院南京土壤研究所 | Method for in-situ restoration and control of polluted site through permeable reactive barrier |
-
2020
- 2020-10-27 CN CN202022418153.1U patent/CN214611726U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014504A (en) * | 2021-12-02 | 2022-02-08 | 江苏省环境科学研究院 | Biological/ultrasonic enhanced adsorption removal system for nitrate pollution of underground water and application thereof |
| CN115259442A (en) * | 2022-07-08 | 2022-11-01 | 广西壮族自治区环境保护科学研究院 | Remediation method for heavy metal chromium-organic solvent composite polluted groundwater |
| CN116274312A (en) * | 2022-10-17 | 2023-06-23 | 中国科学院南京土壤研究所 | Method for in-situ restoration and control of polluted site through permeable reactive barrier |
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