Vertical shaft type percolate guiding and discharging and gas collecting integrated device and construction method

Abstract

The invention discloses a vertical shaft type percolate guiding and discharging and gas collecting integrated device and a construction method, relates to the technical field of vertical shaft type percolate guiding and discharging and gas collecting integration, and discloses the vertical shaft type percolate guiding and discharging and gas collecting integrated device and the construction method. Comprising a prefabricated vertical shaft, a leachate guiding and discharging blind pipe, a landfill gas collecting pipe, an anti-seepage protective film, a seepage monitoring electrode, a differential pressure sensor, a central monitoring system, a high-pressure pump, an infrared methane sensor, a negative pressure gas extractor and a gas generator set, the prefabricated vertical shaft is divided into multiple sections of prefabricated units, and the leachate guiding and discharging blind pipe and the landfill gas collecting pipe are arranged in the prefabricated vertical shaft; the percolate guiding and discharging blind pipe and the landfill gas collecting pipe are connected through a flexible connector to adapt to settlement deformation of a landfill body, the outer wall of the prefabricated vertical shaft is wrapped with an anti-seepage protection film, and the outer wall wrapped with the anti-seepage protection film is provided with a leakage monitoring electrode; by means of the method, construction conflicts of a traditional split type structure can be reduced, the material cost is reduced, and the anti-settling capacity is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of integrated vertical well leachate drainage and gas collection, specifically an integrated vertical well leachate drainage and gas collection device and construction method. Background Technology

[0002] Currently, landfill leachate and landfill gas treatment generally adopt a separate structure, which has the following technical bottlenecks: Structural separation: Traditional leachate drainage systems mostly adopt independent pipeline designs. In CN118704576A, the leachate collection pipe is combined with the end well body. At the same time, in CN202010054903.3, the drainage pipe is flushed with high-pressure water jet to improve clogging. However, manual intervention or fixed flushing cycle is required. However, the independent drainage system cannot dynamically respond to changes in leachate flow rate, has a high clogging frequency, and has high maintenance costs. Fixed geomembrane and drainage pipe need to be frequently disassembled and maintained.

[0003] Poor settlement adaptability: Rigidly connected drainage pipes are prone to breakage when the landfill settles, resulting in poor structural stability. For example, some vertical shafts in patent CN219274019U use reinforced concrete structures, but uneven settlement of the landfill can easily lead to cracking of the well body, increasing the risk of leachate leakage.

[0004] Lagging seepage prevention monitoring: Traditional detection of welding defects in single-layer HDPE membranes in vertical shafts relies on manual inspection, resulting in an excessively long average response time.

[0005] Independent gas collection and passive gas delivery: such as patent CN219274019 U, the landfill gas collection pipe and the leachate drainage pipe are set in the same well, but the gas collection depends on an external air pump, which consumes a lot of energy. Some landfills use simple gas delivery pipes to collect gas, but they are not linked with leachate drainage, resulting in low gas purity.

[0006] Therefore, an integrated vertical well-type leachate drainage and gas collection device and construction method are proposed. Summary of the Invention

[0007] The purpose of this invention is to reduce construction conflicts in traditional split structures, lower material costs, and improve anti-settlement capabilities. This application provides an integrated vertical well leachate drainage and gas collection device and construction method.

[0008] The technical solution adopted in this invention is as follows: A vertical shaft-type integrated leachate drainage and gas collection device and construction method, comprising a prefabricated vertical shaft, a leachate drainage blind pipe, a landfill gas collection pipe, an impermeable protective membrane, a leakage monitoring electrode, a differential pressure sensor, a central monitoring system, a high-pressure pump, an infrared methane sensor, a negative pressure extraction device, and a gas generator set, characterized in that: the prefabricated vertical shaft is divided into multiple prefabricated units, which are connected by flange bolts; the leachate drainage blind pipe and the landfill gas collection pipe are installed inside the prefabricated vertical shaft, and the leachate drainage blind pipe and the landfill gas collection pipe are connected by flexible connectors to adapt to the settlement and deformation of the landfill; the impermeable protective membrane is wrapped around the outer wall of the prefabricated vertical shaft, and the outer wall wrapped by the impermeable protective membrane is provided with a leakage monitoring electrode; The differential pressure sensor is installed at the inlet and outlet of the leachate drainage blind pipe. The differential pressure sensor is electrically connected to the central monitoring system, and the central monitoring system is electrically connected to the high-pressure pump. The infrared methane sensor is installed at the outlet of the landfill gas collection pipe, which is connected to the negative pressure extraction device via a pipeline. The methane gas extracted by the negative pressure extraction device is transported to the gas generator set via a pipeline. The infrared methane sensor, the negative pressure extraction device, and the central monitoring system are electrically connected.

[0009] Furthermore, each prefabricated unit of the prefabricated shaft is 2m long and 1.2m in diameter.

[0010] Furthermore, the flexible connector is a combination of a rubber sealing ring and a bellows compensator.

[0011] Furthermore, the geomembrane is a double-layer HDPE geomembrane with a thickness of 2mm and a welding strength ≥25N / mm.

[0012] Furthermore, a water collection tank is provided at the bottom of the leachate drainage blind pipe, which collects the leachate by gravity and guides it to the water collection well at the bottom of the vertical shaft, and then pumps it to the treatment facility by a submersible pump.

[0013] Furthermore, the outlet of the high-pressure pump is connected to the leachate drainage blind pipe via a pipeline.

[0014] Furthermore, the leachate drainage blind pipe has a diameter of 200 mm, and the landfill gas collection pipe is a stainless steel corrugated pipe with a diameter of 100 mm.

[0015] Integrated construction method for vertical shaft leachate drainage and gas collection: S1. Factory prefabrication: The vertical shaft unit is prefabricated using fiberglass or high-strength concrete, with embedded blind pipes and gas collection pipes, and reserved flange connection interfaces; S2. On-site assembly: Use hoisting equipment to lower the shaft unit section by section, fill the flanges with rubber gaskets and tighten the bolts; S3. Geomembrane welding: Use a double-track hot melt welding machine at a temperature of 200-250℃ to weld the HDPE membrane, and conduct a weld airtightness test at an air pressure of 0.2MPa for 5 minutes with no leakage. S4. Monitoring electrode deployment: Leakage detection electrodes are deployed every 1m along the outer wall of the shaft and connected to the central monitoring system for real-time alarm; S5. System integration: Start the leachate drainage and gas extraction system, and calibrate the threshold values ​​of the differential pressure sensor and the infrared methane sensor; S6. Intelligent Operation and Maintenance: Remotely monitor the efficiency of drainage, gas concentration and equipment status through the Internet of Things platform, and automatically generate maintenance reports on flushing frequency and energy consumption statistics.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: In this invention, by arranging the leachate drainage blind pipe and the landfill gas collection pipe in the same well, construction conflicts of the traditional split structure are reduced, material costs are lowered, and flexible connectors are used to compensate for settlement deformation, thereby improving the anti-settlement capability.

[0017] In this invention, a double-layer HDPE geomembrane combined with deployed leakage electrodes is used to achieve immediate alarm for damage to the geomembrane, reduce the risk of leakage, and improve safety.

[0018] In this invention, differential pressure sensors are installed at the inlet and outlet of the drainage blind pipe. When the differential pressure is greater than 10 kPa, it is determined to be a blockage, which will trigger a high-pressure pump to perform pulse flushing on the blind pipe. Meanwhile, an infrared methane sensor installed at the outlet of the landfill gas collection pipe can activate a negative pressure pumping device when the concentration is greater than 1% LEL. The natural negative pressure generated by the flow of leachate works in conjunction with the electric pumping device to reduce external energy consumption. By using the dual parameters of differential pressure and methane concentration feedback, dynamic regulation is achieved, thereby improving energy utilization efficiency. Attached Figure Description

[0019] Figure 1 This is a flowchart of the construction method of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: Reference Figure 1 The integrated vertical shaft leachate drainage and gas collection device and its construction method include a prefabricated vertical shaft, a leachate drainage blind pipe, a landfill gas collection pipe, an impermeable protective membrane, a leakage monitoring electrode, a differential pressure sensor, a central monitoring system, a high-pressure pump, an infrared methane sensor, a negative pressure extraction device, and a gas generator set. The prefabricated vertical shaft is divided into multiple prefabricated units, which are connected by flange bolts. The leachate drainage blind pipe and the landfill gas collection pipe are installed inside the prefabricated vertical shaft and are connected by flexible connectors. The prefabricated shaft adapts to the settlement deformation of the landfill. Each prefabricated unit is 2m long and 1.2m in diameter. The flexible connector is a combination of a rubber sealing ring and a corrugated pipe compensator. The leachate drainage blind pipe is 200mm in diameter, and the landfill gas collection pipe is a stainless steel corrugated pipe with a diameter of 100mm. Specifically, by arranging the leachate drainage blind pipe and the landfill gas collection pipe in the same well, the construction conflicts of the traditional split structure are reduced, the material cost is reduced, and the flexible connector is used to compensate for settlement deformation, thereby improving the anti-settlement capability.

[0022] Reference Figure 1 The geomembrane is wrapped around the outer wall of the precast shaft, and leakage monitoring electrodes are installed on the outer wall wrapped by the geomembrane. The geomembrane is a double-layer HDPE geomembrane with a thickness of 2mm and a welding strength of ≥25N / mm. Specifically, by using the double-layer HDPE geomembrane in combination with the deployed leakage electrodes, an immediate alarm is triggered for damage to the geomembrane layer, reducing the risk of leakage and improving safety.

[0023] Reference Figure 1 Differential pressure sensors are installed at the inlet and outlet of the leachate drainage blind pipe, and are electrically connected to the central monitoring system, which in turn is electrically connected to the high-pressure pump. An infrared methane sensor is installed at the outlet of the landfill gas collection pipe, which is connected to a negative pressure extraction device via a pipeline. The methane gas extracted by the negative pressure extraction device is transported to the gas generator set through a pipeline. The infrared methane sensor, the negative pressure extraction device, and the central monitoring system are all electrically connected. A water collection tank is installed at the bottom of the leachate drainage blind pipe to collect leachate by gravity and drain it to the water collection well at the bottom of the vertical shaft. The leachate is then pumped to the treatment facility by a submersible pump. The outlet of the high-pressure pump is connected to the leachate drainage blind pipe via a pipeline. Specifically, differential pressure sensors are installed at the inlet and outlet of the drainage blind pipe. When the differential pressure is greater than 10 kPa, it is determined to be blocked, which will trigger the high-pressure pump to perform pulse flushing on the blind pipe. The infrared methane sensor installed at the outlet of the landfill gas collection pipe can start the negative pressure pumping device when the concentration is greater than 1% LEL. The natural negative pressure generated by the flow of leachate works in conjunction with the electric pumping pump to reduce external energy consumption. Dynamic control is achieved by using the dual parameters of differential pressure and methane concentration to improve energy utilization.

[0024] Example 2: Reference Figure 1The construction method integrates vertical shaft leachate drainage and gas collection. Prefabricated units are constructed in the factory using fiberglass or high-strength concrete, with embedded drainage blind pipes and gas collection pipes, and pre-installed flange connection interfaces. On-site assembly involves lowering the shaft units section by section using hoisting equipment, filling the flanges with rubber gaskets and tightening bolts. Geomembrane welding is performed using a double-rail hot-melt welding machine at 200-250℃ to weld the HDPE membrane, followed by a weld airtightness test at 0.2MPa pressure for 5 minutes with no leakage. Leakage detection electrodes are installed every 1m along the outer wall of the shaft, connected to a central monitoring system for real-time alarms. System commissioning involves activating the leachate drainage and gas extraction system. The system calibrates the threshold values ​​of differential pressure sensors and infrared methane sensors; it implements intelligent operation and maintenance by remotely monitoring drainage efficiency, gas concentration, and equipment status through an IoT platform, automatically generating flushing frequency and energy consumption statistics reports; specifically, the shaft unit is prefabricated using fiberglass or high-strength concrete, with embedded drainage blind pipes and gas collection pipes, achieving simultaneous pre-embedding of gas and liquid dual channels, resulting in high structural integration and avoiding sealing risks caused by on-site openings; simultaneously, the hoisting equipment lowers the unit section by section, filling the flanges with rubber gaskets and tightening bolts to reduce shaft verticality errors. Through the triple innovation of structural integration, intelligent monitoring, and IoT operation and maintenance, it alleviates problems such as seepage failure, response lag, and rough operation and maintenance during shaft construction.

[0025] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0026] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vertical shaft-type integrated leachate drainage and gas collection device, comprising a prefabricated vertical shaft, a leachate drainage blind pipe, a landfill gas collection pipe, an impermeable protective membrane, a leakage monitoring electrode, a differential pressure sensor, a central monitoring system, a high-pressure pump, an infrared methane sensor, a negative pressure extraction device, and a gas generator set, characterized in that: The prefabricated shaft is divided into multiple prefabricated units and connected by flange bolts. The leachate drainage blind pipe and the landfill gas collection pipe are installed inside the prefabricated shaft. The leachate drainage blind pipe and the landfill gas collection pipe are connected by flexible connectors to adapt to the settlement and deformation of the landfill. The anti-seepage protective membrane is wrapped around the outer wall of the prefabricated shaft, and the outer wall wrapped by the anti-seepage protective membrane is equipped with leakage monitoring electrodes. The differential pressure sensor is installed at the inlet and outlet of the leachate drainage blind pipe. The differential pressure sensor is electrically connected to the central monitoring system, and the central monitoring system is electrically connected to the high-pressure pump. The infrared methane sensor is installed at the outlet of the landfill gas collection pipe, which is connected to the negative pressure extraction device via a pipeline. The methane gas extracted by the negative pressure extraction device is transported to the gas generator set via a pipeline. The infrared methane sensor, the negative pressure extraction device, and the central monitoring system are electrically connected.

2. The vertical shaft-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: Each prefabricated unit of the prefabricated shaft is 2m long and 1.2m in diameter.

3. The vertical shaft-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: The flexible connector is a combination of a rubber sealing ring and a bellows compensator.

4. The vertical well-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: The geomembrane is a double-layer HDPE geomembrane with a thickness of 2mm and a welding strength of ≥25N / mm.

5. The vertical shaft-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: The bottom of the leachate drainage blind pipe is equipped with a water collection tank, which collects leachate by gravity and drains it to the water collection well at the bottom of the vertical shaft, and then pumps it to the treatment facility by a submersible pump.

6. The vertical shaft-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: The outlet of the high-pressure pump is connected to the leachate drainage blind pipe via a pipeline.

7. The vertical shaft-type integrated leachate drainage and gas collection device as described in claim 1, characterized in that: The leachate drainage blind pipe has a diameter of 200 mm, and the landfill gas collection pipe is a stainless steel corrugated pipe with a diameter of 100 mm.

8. A construction method for integrated vertical well leachate drainage and gas collection, characterized in that... The apparatus of any one of claims 1 to 7 is used: S1. Factory prefabrication: The vertical shaft unit is prefabricated using fiberglass or high-strength concrete, with embedded blind pipes and gas collection pipes, and reserved flange connection interfaces; S2. On-site assembly: Use hoisting equipment to lower the shaft unit section by section, fill the flanges with rubber gaskets and tighten the bolts; S3. Geomembrane welding: Use a double-track hot melt welding machine at a temperature of 200-250℃ to weld the HDPE membrane, and conduct a weld airtightness test at an air pressure of 0.2MPa for 5 minutes with no leakage. S4. Monitoring electrode deployment: Leakage detection electrodes are deployed every 1m along the outer wall of the shaft and connected to the central monitoring system for real-time alarm; S5. System integration: Start the leachate drainage and gas extraction system, and calibrate the threshold values ​​of the differential pressure sensor and the infrared methane sensor; S6. Intelligent Operation and Maintenance: Remotely monitor the efficiency of drainage, gas concentration and equipment status through the Internet of Things platform, and automatically generate maintenance reports on flushing frequency and energy consumption statistics.

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