CN110777853B

CN110777853B - Method for repairing HDPE (high-density polyethylene) film leak of landfill slope

Info

Publication number: CN110777853B
Application number: CN201910908755.4A
Authority: CN
Inventors: 刘军; 潘天骐; 郭燕; 戴昕; 蔡琳琳; 宫建瑞; 刘彦奎
Original assignee: Nanjing Wondux Environmental Protection Technology Co ltd
Current assignee: Nanjing Wondux Environmental Protection Technology Co ltd
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2021-08-06
Anticipated expiration: 2039-09-25
Also published as: CN110777853A

Abstract

The invention provides a landfill side slope HDPE membrane leak repairing method, which comprises the following steps: accurately positioning a leachate leakage point in the landfill by using a landfill leak detection technology; if a leak point appears on the impermeable side slope of the landfill, judging the shape of the leak by utilizing conductivity data in the leak detection technology and a three-dimensional imaging technology; after confirming the shape and the position of the leaking point, drilling a directional inclined shaft on the outer side of the side slope of the landfill site, and drilling towards the leaking point, wherein the depth of the inclined shaft is required to pass through the position of a leak hole of the landfill site and penetrate into a pile body; taking out the drill bit, and extending into the guide pipe to extract leachate, sludge and residues accumulated in the well; and injecting an impermeable material into the inclined well to fill the drilled hole. The invention has small disturbance to the garbage pile body, and has less landfill gas escaping and less harm to the environment in the process of repairing the leakage point of the landfill; the anti-seepage plug/anti-seepage wall has a certain angle, so that the anti-seepage plug/anti-seepage wall can play the roles of blocking a hole and guiding water, and the possibility of secondary leakage at the original leakage position is reduced to the maximum extent.

Description

Method for repairing HDPE (high-density polyethylene) film leak of landfill slope

Technical Field

The invention belongs to the technical field of landfill repair, and particularly relates to a method for repairing a leak of a HDPE (high density polyethylene) film on a side slope of a landfill.

Background

The landfill seepage-proofing system in China mainly selects a geomembrane as a main seepage-proofing layer, wherein HDPE membranes are widely used as seepage-proofing geomembranes in China. However, in the process of construction and landfill, the HDPE film has the risk of being torn by an excavator and stones or being cut by sharp substances in the landfill, and the thickness of the HDPE film in the sealing standard of the landfill in China is specified to be 1-1.5 mm, which is far lower than the national standards developed abroad, and along with the lapse of time, an impermeable layer in the landfill is inevitably damaged, so that leachate leaks, and the surrounding environment is polluted. The conventional landfill leakage repairing measures adopt a method of excavation and drainage. However, this method has the disadvantages of long time consumption and generation of a large amount of off-flavor.

Disclosure of Invention

The invention aims to provide a method for repairing a slope damage leak of a landfill, which can be used in the landfill with a damaged slope impermeable film. And overcomes the defects of long time consumption and large amount of peculiar smell generation in the traditional leakage repairing method.

The technical scheme for realizing the purpose is as follows:

a landfill slope HDPE membrane leak repairing method comprises the following steps:

step 1: accurately positioning a leachate leakage point in the landfill by using a three-dimensional resistance imaging technology;

step 2: judging the shape of the missing point by utilizing conductivity data in a three-dimensional resistance imaging technology and a three-dimensional stereo imaging technology;

and step 3: after confirming the shape and the position of the leaking point, performing directional inclined shaft drilling on the outer side of the side slope of the landfill to the direction of the leaking point, wherein the inclined shaft extends into the landfill and covers the leaking point;

and 4, step 4: after drilling, taking out the drill bit, and extracting the leachate, sludge and residues accumulated in the inclined shaft;

and 5: and injecting an impermeable material into the inclined shaft, wherein the injected impermeable material at least fills the inclined shaft to form an impermeable plug or an impermeable wall.

Preferably, the included angle between the inclined shaft and the horizontal line is 0-90 degrees.

Preferably, the horizontal distance L between the wellhead and the leak point of the inclined shaft is H multiplied by tan^-1Theta and H are vertical distances between the leakage point and the earth surface; theta is the drilling angle.

Preferably, the inclined shaft extends 1-2 meters into the garbage dump in the landfill.

Preferably, the barrier material is concrete or other barrier filler.

Preferably, the pore diameter of each inclined well is 0.6-0.7 m.

Has the advantages that:

the method excavates from the outside of the landfill, and does not damage the drainage guide equipment in the landfill in the process of repairing the leak of the landfill; the disturbance to the garbage dump body is small, so that in the process of leak repairing of a landfill site, less landfill gas is released, and the damage to the environment is small; the anti-seepage plug/anti-seepage wall has a certain angle, so when leachate or rainwater generated by garbage per se leaks downwards, the anti-seepage plug/anti-seepage wall can play the roles of blocking a hole and draining, and the possibility of secondary leakage at the original leakage position is reduced to the greatest extent.

Drawings

FIG. 1 is a flow chart of a landfill slope restoration technique;

fig. 2 is a schematic view of a vulnerability shape: hole-shaped (left) and sawtooth-shaped (right);

fig. 3 is a schematic view of landfill slope vulnerability repair: wherein 1 is a slant well drilling machine; 2 is a leakage point; and 3, a landfill.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The invention comprises the following steps

Step 1: the method comprises the following steps of (1) depicting a leachate accumulation condition in a landfill by utilizing a three-dimensional resistance imaging technology, and determining a leakage point position of the landfill and leachate pollution plume;

the method comprises the following specific steps: 1. arranging electrodes of the resistance measuring probes along the section in a one-time array mode; 2. acquiring distribution information of geoelectric sections at different depths below the section in the measuring landfill; 3. and processing and analyzing the recorded landfill resistivity information through an inversion algorithm, and drawing a leachate distribution map in the landfill.

Step 2: judging the shape of a landfill leak according to the leakage point position and the shape of the pollution plume;

the method comprises the following specific steps: 1. judging whether the anti-leakage film at the edge of the landfill is broken or not (if the anti-leakage film is broken, leachate pollution feathers can appear); 2. judging the shape of the leachate pollution plume to find the position of a leakage source; 3. and judging the damage shape and size of the impermeable layer inside the landfill according to the pollution plume state of the leachate and the position of the pollution source.

And step 3: if the side slope of the landfill has a leaking point, performing inclined well drilling operation by using directional drilling or inclined well drilling at a position L away from the landfill leak, wherein the calculation formula of the distance L is as follows:

L＝H×tan^-1θ

wherein: l is the horizontal distance between the drilling position and the leaking point position, and the unit is m; h is the vertical distance between the leakage point and the earth surface, and the unit is m; theta is the drilling angle.

The inclined shaft passes through the position of a leakage point of the landfill and extends into the garbage dump body for 1-2 meters; the inclined shaft is required to cover the leakage point, if the area of the leakage point is small, a cylindrical hole is formed by drilling, and if the area of the leakage point is large, a groove is formed by continuously drilling;

and 4, step 4: after drilling, taking out the drill bit, and extending into the guide pipe to extract leachate, sludge and residues accumulated in the well;

and 5: after cleaning, concrete or other impermeable filling agents are injected into the well by using the guide pipe, and the injected impermeable filling agents at least fill the inclined well.

Claims

1. A landfill slope HDPE membrane leak repairing method is characterized by comprising the following steps:

and step 3: after confirming the shape and the position of the leaking point, performing directional inclined shaft drilling on the outer side of the side slope of the landfill to the direction of the leaking point, wherein the inclined shaft extends to 1-2 meters in the landfill and covers the leaking point;

and 5: and injecting a seepage-proofing material into the inclined well, wherein the injected seepage-proofing material at least fills the drilled hole.

2. The method for repairing the HDPE film leak on the side slope of the landfill site as claimed in claim 1, wherein the impermeable material is concrete.

3. The method for repairing HDPE membrane leaks in side slopes of landfill sites as claimed in claim 1, wherein the diameter of the inclined shaft is 0.6-0.7 m.