CN113175003A - Contaminated site separation system based on bottom is weak permeable stratum - Google Patents

Contaminated site separation system based on bottom is weak permeable stratum Download PDF

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Publication number
CN113175003A
CN113175003A CN202110554386.0A CN202110554386A CN113175003A CN 113175003 A CN113175003 A CN 113175003A CN 202110554386 A CN202110554386 A CN 202110554386A CN 113175003 A CN113175003 A CN 113175003A
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China
Prior art keywords
well
monitoring
type
water
monitoring well
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Withdrawn
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CN202110554386.0A
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Chinese (zh)
Inventor
车平
马娟
李孟琳
张跃
胡光云
颜庭成
师森
康红军
张旭东
唐勇
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Jiangsu East China Geological Construction Group Co ltd
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Jiangsu East China Geological Construction Group Co ltd
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Priority to CN202110554386.0A priority Critical patent/CN113175003A/en
Publication of CN113175003A publication Critical patent/CN113175003A/en
Withdrawn legal-status Critical Current

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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D31/00—Protective arrangements for foundations or foundation structures; Ground foundation measures for protecting the soil or the subsoil water, e.g. preventing or counteracting oil pollution
    • E02D31/002—Ground foundation measures for protecting the soil or subsoil water, e.g. preventing or counteracting oil pollution
    • E02D31/004—Sealing liners
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D31/00—Protective arrangements for foundations or foundation structures; Ground foundation measures for protecting the soil or the subsoil water, e.g. preventing or counteracting oil pollution
    • E02D31/002—Ground foundation measures for protecting the soil or subsoil water, e.g. preventing or counteracting oil pollution
    • E02D31/006—Sealing of existing landfills, e.g. using mining techniques
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D33/00—Testing foundations or foundation structures
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Structural Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Hydrology & Water Resources (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

The invention provides a polluted site separation system based on a weakly permeable layer at the bottom, which is characterized by comprising an impervious curtain arranged around a polluted site, wherein a flood interception ditch is arranged at the inner side of the impervious curtain, first-class monitoring wells are arranged at two sides of the impervious curtain, first-class monitoring wells are also arranged in an uncontaminated area outside the impervious curtain and serve as background reference wells, and the water quality in the first-class monitoring wells and the water quality in the background reference wells are compared to determine the separation effect of the separation system. The method can detect whether gaps exist among the pile bodies, can determine whether the defective parts of the pile bodies are permeable, can well judge the short-term and long-term effects of pollution control under the conditions that a polluted site is a weakly permeable layer relative to a water-resisting layer and cross-flow pollution possibly exists, and is economical, efficient, low in cost, simple, direct, simple and convenient to operate.

Description

Contaminated site separation system based on bottom is weak permeable stratum
Technical Field
The invention relates to the technical field of underground water prevention and control, in particular to a polluted site blocking system based on a weakly permeable layer at the bottom.
Background
In order to meet the needs of social development, a large number of farmlands are levied in China, and chemical enterprises such as paper mills, power plants and the like are changed. These enterprises generate a great amount of solid waste in the annual production operation, the surface of the solid waste pile body is not covered with protective measures, most of the bottom of the solid waste pile body is not provided with anti-seepage measures, and the toxic and harmful substances in the solid waste have the risk of migration and diffusion.
The solid waste pollutants in the in-service plant area can be prevented and treated by adopting the measures of vertical impervious curtain sealing and pollutant in-situ treatment. The vertical impervious curtain can increase the length of the circumfluence and obstruct the solid waste polluted liquid from polluting the water source outside the field.
After the adopted isolation curtain is implemented by combining with pollution control measures such as drainage (or water pumping), under the condition that a polluted site is a weakly permeable layer relative to a waterproof layer and cross-flow pollution possibly exists, no good method is provided for judging the short-term and long-term effects of pollution control under the conditions.
At present, the detection method for the impervious curtain in the industry generally detects the integrity and the material strength, and the detection methods belong to indirect detection methods, cannot detect whether gaps exist among pile bodies, cannot determine whether defect parts of pile bodies are permeable, and are not suitable for detecting the reliability of the long-term action of the impervious curtain, so that a more direct, more convenient and more long-acting detection method is necessary.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a polluted site blocking system based on a weakly permeable layer at the bottom, which can be used for measuring whether gaps exist among pile bodies by a simpler direct long-acting method, determining whether the defect parts of the pile bodies are permeable, and particularly well judging the short-term and long-term effects of pollution control under the conditions that the polluted site is the weakly permeable layer relative to a water-resisting layer and cross-flow pollution possibly exists.
In order to solve the technical problems, the invention adopts the technical scheme that: the utility model provides a pollute place separation system based on bottom is weak permeable stratum, includes the prevention of seepage curtain that sets up around polluting the place, prevention of seepage curtain inboard is provided with cuts the flood ditch, in prevention of seepage curtain both sides are provided with first type monitoring well, do not pollute the region outside prevention of seepage curtain and also be provided with first type monitoring well and make background reference well, compare quality of water in first type monitoring well and the background reference well in order to confirm the separation effect of separation system.
Furthermore, the first type of monitoring well penetrates into the relative water-resisting layer, a well pipe is arranged in the monitoring well, a slit is formed in the lower end of the well pipe, mung bean sand is filled between the outer wall of the well pipe with the slit and the well wall, and the top of the mung bean sand is filled to the ground through clay or bentonite.
Furthermore, the well hole is sealed by a well cover, and a water-stopping rubber ferrule is arranged in the well cover.
Further, cut the flood ditch and include brick lateral wall and compound bottom surface, the brick lateral wall is filled with clay, compound bottom surface includes rubble bed course, C20 bed course and waterproof mortar by supreme down in proper order.
The monitoring well further comprises a second type monitoring well, the depth of the second type monitoring well penetrating into the water-resisting layer is larger than that of the first type monitoring well, a well pipe is arranged in the monitoring well, the tail end of the well pipe is subjected to sealing treatment, a slit is formed in the lower end of the well pipe, mung bean sand is filled between the outer wall of the well pipe with the slit and the well wall, and the top of the mung bean sand is filled to the ground by clay or bentonite.
Furthermore, a water level monitoring device is arranged in the second type of monitoring well, and water level information is transmitted to the control center and used for keeping the water level in the second type of monitoring well stable.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention can detect whether gaps exist among the pile bodies.
2. The method can determine whether the defective part of the pile body is permeable to water or not.
3. The method can well judge the short-term and long-term effects of pollution control under the conditions that the polluted site is a weakly permeable layer relative to a water-resisting layer and cross-flow pollution possibly exists.
4. The invention is economical and efficient and has low cost.
5. The invention is simple and direct, and the operation is simple and convenient.
Drawings
The disclosure of the present invention is illustrated with reference to the accompanying drawings. It is to be understood that the drawings are designed solely for the purposes of illustration and not as a definition of the limits of the invention. In the drawings, like reference numerals are used to refer to like parts. Wherein:
fig. 1 is a schematic plan view of a detection system for detecting the implementation effect of a contaminated site barrier system based on a weakly permeable floor at the bottom of the detection system.
Fig. 2 is a schematic cross-sectional view of a second type of monitoring well according to the present invention.
Fig. 3 is a schematic cross-sectional view of the flood interception ditch of the present invention.
Reference numbers in the figures: 1-impervious curtain, 2-flood interception ditch, 21-bricked side wall, 22-waterproof mortar, 23-concrete C20 cushion layer, 24-broken stone cushion layer, 3-mung bean sand, 4-well pipe, 5-clay or bentonite, 6-well cover and 7-sealing ring.
Detailed Description
It is easily understood that according to the technical solution of the present invention, a person skilled in the art can propose various alternative structures and implementation ways without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical aspects of the present invention, and should not be construed as all of the present invention or as limitations or limitations on the technical aspects of the present invention.
An embodiment according to the present invention is shown in conjunction with fig. 1-3. The utility model provides a pollute place separation system based on bottom is weak permeable stratum, includes the impervious curtain 1 that sets up around polluting the place, is provided with in impervious curtain 1 inboard and cuts the flood ditch 2 and all is provided with first kind monitoring well (SW I) in impervious curtain 1 both sides, is provided with first kind monitoring well as background reference well for polluting the area outside impervious curtain 1, compares first kind monitoring well and background reference well in quality of water in order to confirm the separation effect of separation system.
Above-mentioned first type monitoring well is deepened relative water barrier certain distance, is provided with well casing 4 in the monitoring well, and the lower extreme of well casing 4 is provided with the slot, has filled mung bean sand 3 between the well casing 4 outer wall that has the slot and the wall of a well, and it is solid to fill with clay or bentonite 5 between the well casing 4 outer wall that does not have the slot and the wall of a well, plays sealed effect, prevents that surface water from getting into in the well casing 4. The well hole is sealed by a well cover 6, and a water-stopping rubber ferrule is arranged in the well cover 6.
The anti-seepage curtain 1 is provided with a flood interception ditch 2, the flood interception ditch 2 comprises a brick side wall 21 and a composite bottom surface, the composite bottom surface is positioned on the anti-seepage curtain 1 and sequentially comprises a broken stone cushion layer 24, a concrete C20 cushion layer 23 and waterproof mortar 22 from bottom to top, the brick side wall 21 is positioned on the waterproof mortar 22 and is relatively distributed at two ends of the anti-seepage curtain 1 in the width direction and filled with clay, so that the flood interception ditch 2 is integrally in an inwards concave shape, and the flood interception ditch 2 is flush with the ground after construction is completed and is used for ensuring that solid waste seepage liquid and rainwater in a plant area cannot pollute a peripheral site.
A second type monitoring well (SW II) is further arranged in the impervious curtain 1, the second type monitoring well penetrates into the relative waterproof layer and the depth of the second type monitoring well is larger than that of the first type monitoring well, a sealing ring 7 is arranged at the part of the second type monitoring well penetrating into the relative waterproof layer, and the rest part of the second type monitoring well is the same as that of the first type monitoring well.
Because of the water level in the second kind of monitoring well needs to be monitored, can adopt the water level mode in the second kind of monitoring well of periodic manual determination or set up water level monitoring device in the second kind of monitoring well and monitor like photometry level gauge or sonar, and can be with direct remote transmission of water level information to control center department, because of the water level of normally launching water is relatively stable, so can borrow this settlement water level threshold value, when water level is higher than the water level threshold value of settlement in the second kind of monitoring well, report to the police by control center and directly draw water through artificial mode and handle or set up the immersible pump in the second kind of monitoring well, directly accomplish the action of drawing water by control center.
The technical scheme of the invention is specifically explained by taking the treatment of the polluted site of No. 7 land of Shandong Bohui paper industry Co., Ltd as an example in combination with the attached drawings.
Hydrogeology within the site is as follows:
(1) the field is stable and has no adverse geological effect.
(2) The main physical layers in the field mainly comprise a fill layer, a solid waste layer and an original soil layer from top to bottom.
(3) The solid waste layer is distributed in the field basically, the whole thickness distribution is relatively uniform, the average thickness is about 6.85m, and the volume is about 2132288m3(ii) a The average thickness of the filling layer is about 0.24m, and the distribution area is about 311283m2Volume of about 250276m3The original soil layer under the solid waste layer is relatively stable.
(4) The water level of a diving aquifer in a factory area is mainly influenced by atmospheric precipitation and surface water and changes seasonally.
The underground water is closely related to the diving water power, the underground water supplies surface water under the current situation, the field is solidified, the field is in the construction stage at present, the underground water has small mobility and higher water level than the periphery, and the underground water flows from the center to the periphery.
The method comprises the following steps: according to design, the vertical impervious curtain mainly adopts 650@900 triaxial deep stirring piles, and according to actual conditions on site, 800@600 double-row jet grouting piles are adopted in triaxial non-construction sections; and locally reinforcing by adopting compaction grouting according to the condition. The cement is 42.5-grade ordinary portland cement.
The pile end of the curtain pile enters 2-1 layers of powdery clay which is more than or equal to 6.50m, and the average pile length is about 20.0 m. The 2-1 layer is a relative water-proof layer, and the vertical permeability coefficient Kv thereof is 2.31 x 10-5cm/s, horizontal permeability coefficient Kh of 3.45X 10-5cm/s, is a weakly permeable layer.
Step two: the top of the anti-seepage curtain pile is provided with a flood interception ditch, so that solid waste seepage and rainwater in a plant area can not pollute a peripheral field.
Step three: the first type monitoring wells are respectively arranged on the inner side and the outer side of the periphery of the impervious curtain, and the first type monitoring wells are arranged at the far ends of the outer sides of the impervious curtain and are used as background reference wells for monitoring the pollution diffusion control effect of the first diving aquifers on the inner side and the outer side of the impervious curtain. The aperture of the first monitoring well is 300mm, the bottom of the first monitoring well extends into 2-1 layers and is more than or equal to 2.0m, a well pipe with the diameter of 160mm is arranged in the first monitoring well, a light pipe is arranged in the range of 2m of the upper end of the well pipe, and a UPVC pipe with a slit is arranged at the lower end of the well pipe. Mung bean sand is filled between the outer wall of the well pipe and the inner wall of the hole, and the top of the mung bean sand is filled to the ground by clay or bentonite. The top of the well hole is sealed by the well cover for a long time, and the inside of the well cover is provided with a water-stopping rubber ferrule.
Step four: and 3 second-class monitoring wells are uniformly arranged in the impervious curtain enclosure ring and used for monitoring whether the cross-flow pollution occurs to the 2-1 layer of relative water-resisting layer and the 2-2 layer of micro-pressure bearing water at the bottom of the impervious curtain. The bottom of the second type of monitoring well hole extends into 2-1 layers and is more than or equal to 4.0m, and a sealing ring is added within the layer thickness range of 2-1 layers to isolate the monitoring interference of the diving on the micro confined water. The rest of the second monitoring well is the same as the first monitoring well.
Step five: after the steps are completely finished, maintaining for about 28 days, extracting water in the first type monitoring wells and the background reference wells inside and outside the impervious curtain, detecting the water quality, and comparing. If the water quality parameters of the monitoring well at the outer side of the impervious curtain are not greatly different from those of the background reference well, and the difference is obvious compared with that of the monitoring well at the outer side, the implementation of the impervious curtain is successful; otherwise, the seepage-proofing curtain is problematic to implement and needs to be reinforced and other measures to remedy. The similar method can carry out monitoring for a long time so as to check the implementation effect of the impervious curtain in due time.
Step six: detecting the water level of a second type of monitoring well, if the water level is found to rise, indicating that the site has overflow pollution, and adopting measures such as water pumping and the like for control; on the contrary, the seepage-proof curtain is well implemented, has no risk of cross-flow pollution and does not need to be processed.
The working principle of the invention is to detect and compare the water quality by extracting the water in the first type of monitoring well and the background reference well inside and outside the impervious curtain. If the water quality parameters of the monitoring well at the outer side of the impervious curtain are not greatly different from those of the background reference well, and the difference is obvious compared with that of the monitoring well at the outer side, the implementation of the impervious curtain is successful; otherwise, the seepage-proofing curtain is problematic to implement and needs to be reinforced and other measures to remedy. The similar method can carry out monitoring for a long time so as to check the implementation effect of the impervious curtain in due time.
In addition, by detecting the water level of the second type of monitoring well, if the water level is found to rise, the site is over-flowing polluted, measures such as water pumping and the like need to be taken, and pumped water is discharged to the leachate treatment tank for treatment; on the contrary, the seepage-proof curtain is well implemented, has no risk of cross-flow pollution and does not need to be processed.
The technical scope of the present invention is not limited to the above description, and those skilled in the art can make various changes and modifications to the above-described embodiments without departing from the technical spirit of the present invention, and such changes and modifications should fall within the protective scope of the present invention.

Claims (6)

1. The utility model provides a pollute place separation system based on bottom is weak permeable stratum, its characterized in that, includes impervious curtain (1) around polluting the place setting, impervious curtain (1) inboard is provided with cuts flood ditch (2), in impervious curtain (1) both sides are provided with first type monitoring well, do not pollute the region outside impervious curtain (1) and also be provided with first type monitoring well and make background reference well, compare quality of water in first type monitoring well and the background reference well in order to confirm the separation effect of separation system.
2. The system for blocking the polluted site based on the weakly permeable bottom layer as claimed in claim 1, wherein the monitoring well of the first type is deep into the relative water-resisting layer, a well pipe (4) is arranged in the monitoring well, the lower end of the well pipe (4) is provided with a slit, green bean sand (3) is filled between the outer wall of the well pipe (4) with the slit and the well wall, and the top of the green bean sand (3) is filled to the ground by clay or bentonite (5).
3. The pollution site barrier system based on a bottom weakly permeable layer according to claim 2, wherein the well is sealed with a well lid (6), and a water-stopping rubber ferrule is arranged inside the well lid (6).
4. The pollution site barrier system based on the bottom weak permeable layer as claimed in claim 1, wherein the flood interception ditch (2) comprises a composite bottom surface and brick side walls (3) arranged on the composite bottom surface, the brick side walls (3) are filled with clay, and the composite bottom surface comprises a gravel cushion layer (24), a concrete C20 cushion layer (23) and waterproof mortar (22) from bottom to top in sequence.
5. The system for blocking the polluted site based on the weakly permeable stratum at the bottom is characterized by further comprising a second type of monitoring well, wherein the second type of monitoring well is positioned in the impervious curtain (1) and penetrates deeper than the first type of monitoring well in the depth direction, a well pipe (4) is arranged in the monitoring well, the tail end of the well pipe (4) is sealed, a slit is formed in the lower end of the well pipe (4), mung bean sand (3) is filled between the outer wall of the well pipe (4) with the slit and the well wall, and the top of the mung bean sand (3) is filled to the ground by clay or bentonite (5).
6. The contaminated site barrier system based on a weakly permeable bottom layer according to claim 5, wherein a water level monitoring device is arranged in the second type of monitoring well, and water level information is transmitted to a control center for keeping the water level in the second type of monitoring well stable.
CN202110554386.0A 2021-05-20 2021-05-20 Contaminated site separation system based on bottom is weak permeable stratum Withdrawn CN113175003A (en)

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Application Number Priority Date Filing Date Title
CN202110554386.0A CN113175003A (en) 2021-05-20 2021-05-20 Contaminated site separation system based on bottom is weak permeable stratum

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114232663A (en) * 2022-01-12 2022-03-25 中国海洋大学 Variable-permeability underground curtain for preventing seawater intrusion and land source pollution and construction method thereof
CN115178577A (en) * 2022-07-07 2022-10-14 江苏华东地质建设集团有限公司 Soil and underground water pollution prevention and control system and use method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114232663A (en) * 2022-01-12 2022-03-25 中国海洋大学 Variable-permeability underground curtain for preventing seawater intrusion and land source pollution and construction method thereof
CN114232663B (en) * 2022-01-12 2022-10-28 中国海洋大学 Variable-permeability underground curtain for preventing seawater intrusion and land source pollution and construction method thereof
CN115178577A (en) * 2022-07-07 2022-10-14 江苏华东地质建设集团有限公司 Soil and underground water pollution prevention and control system and use method thereof

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Application publication date: 20210727

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