阅读说明：本技术 一种自适应放气杆及浅层气有控放气回收系统及方法 (Self-adaptive air release rod and shallow layer air controlled air release recovery system and method ) 是由 洪义 王立忠 赵爽 朱连根 王强 茅奇辉 于 2019-08-12 设计创作，主要内容包括：本发明公开了自适应放气杆及浅层气有控放气回收系统及方法,自适应放气杆包括第二空心探杆和第一空心探杆；第二空心探杆连接于第一空心探杆下部,且直径大于第一空心探杆；第二空心探杆中部开有沿周向的凹槽,凹槽内设有滑套,滑套下端为楔形；且凹槽上部开有放气孔,滑套与放气孔长度之和小于凹槽长度,且滑套长度大于放气孔长度；在自适应放气杆插入过程中,滑套滑动至凹槽上部,掩盖放气孔；当上拔过程中,滑套滑动至凹槽下部,放气孔暴露,通过放气孔放气。采用基于该放气杆的回收系统和方法解决了传统浅层气释放技术中的淤泥堵杆的问题,一体式的设计,使其探头可回收,降低了浅层气释放的成本,适于工业化应用。(The invention discloses a self-adaptive air release rod and a shallow layer air controlled air release recovery system and a method, wherein the self-adaptive air release rod comprises a second hollow probe rod and a first hollow probe rod; the second hollow probe rod is connected to the lower part of the first hollow probe rod, and the diameter of the second hollow probe rod is larger than that of the first hollow probe rod; a groove along the circumferential direction is formed in the middle of the second hollow probe rod, a sliding sleeve is arranged in the groove, and the lower end of the sliding sleeve is wedge-shaped; the upper part of the groove is provided with an air vent, the sum of the lengths of the sliding sleeve and the air vent is less than the length of the groove, and the length of the sliding sleeve is greater than the length of the air vent; in the insertion process of the self-adaptive air bleed rod, the sliding sleeve slides to the upper part of the groove to cover the air bleed hole; when the sliding sleeve is pulled up, the sliding sleeve slides to the lower part of the groove, the air vent is exposed, and air is released through the air vent. The recovery system and the recovery method based on the air release rod solve the problem that the sludge blocks the rod in the traditional shallow air release technology, and due to the integrated design, the probe can be recovered, so that the cost of shallow air release is reduced, and the recovery system and the recovery method are suitable for industrial application.)

1. An adaptive air release rod comprises a second hollow probe rod (39) and a first hollow probe rod (40); the second hollow probe rod (39) is connected to the lower part of the first hollow probe rod (40), and the diameter of the second hollow probe rod is larger than that of the first hollow probe rod (40); the middle part of the second hollow probe rod (39) is provided with a groove along the circumferential direction, a sliding sleeve (23) is arranged in the groove, and the lower end of the sliding sleeve (23) is wedge-shaped; the upper part of the groove is provided with an air vent (38), the sum of the lengths of the sliding sleeve (23) and the air vent (38) is less than the length of the groove, and the length of the sliding sleeve (23) is greater than the length of the air vent (38); in the insertion process of the self-adaptive deflation rod, the sliding sleeve (23) slides to the upper part of the groove to cover the deflation hole (38); when the sliding sleeve (23) slides to the lower part of the groove in the upward pulling process, the air vent (38) is exposed, and air is released through the air vent.

2. the bleed lever of claim 1, wherein the bleed holes 38 are vertically disposed kidney holes.

3. A shallow air controlled deflation recovery method based on soil mechanics parameter measurement, which is characterized in that the method is realized based on the self-adaptive deflation rod of claim 1, and comprises the following steps:

(1) Inserting the self-adaptive air bleed rod into a shallow-layer-contained gas soil layer, and simultaneously collecting penetration cone tip resistance, side wall frictional resistance and pore water pressure of the soil layer at the insertion position;

(2) Identifying a gas-containing sandy lens body according to the penetration cone tip resistance, the side wall frictional resistance and the pore water pressure collected in the step (1);

(3) further inserting a self-adaptive air release rod, and identifying the air-containing sandy lens body in real time until the depth of a soil layer without the air-containing sandy lens body or the depth of a building foundation;

(4) The self-adaptive air release rod is pulled upwards to release shallow air.

4. A method according to claim 3, characterized in that the deflation rate is also controlled by a gas mass flow controller 18, said gas mass flow controller 18 being in communication with the central bore of the second hollow probe 39, the first hollow probe 40 through a tube.

5. a method according to claim 4, characterized in that the gas-cement mixture emerging from the central bore of the second hollow probe (39), the first hollow probe (40) is subjected to a separation device to remove sludge and water, and the gas is fed to the gas mass flow controller (18).

6. The method according to claim 4, characterized in that it further comprises a recovery of gas, in particular: the gas flowing out of the gas mass flow controller (18) is pressurized by a supercharger and then is input into a gas storage tank.

7. A shallow layer gas controlled deflation recovery system based on soil layer mechanics parameter measurement, which is characterized by comprising the self-adaptive deflation rod of claim 1, a hydraulic loading system for inserting the self-adaptive deflation rod, an in-situ investigation system for acquiring the penetration cone tip resistance, the side wall friction resistance and the pore water pressure of the insertion part of the self-adaptive deflation rod, a gas-water-cement separation system for separating the gas-cement mixture discharged by the self-adaptive deflation rod, a gas flow servo system for controlling the gas release rate of the self-adaptive deflation rod and a gas recovery system for gas recovery.

Technical Field

The invention relates to a self-adaptive air release rod and shallow air controlled air release recovery system and method, which can realize controlled air release and recovery utilization of shallow air and simultaneously obtain in-situ mechanical parameters of soil and measurement of in-situ methane concentration.

Background

a large amount of organic matters exist in the coastal soft soil, and under a long-term closed condition, the microorganisms convert the organic matters in the coastal soft soil into methane gas, and the methane gas is accumulated for a long time and is sealed underground to form shallow gas.

Shallow air is widely distributed in coastal soft soil of five continents in the world, and the shallow air easily causes disasters and seriously threatens the underground construction of coastal cities. Due to 'sea going and sea going back' since the fourth era, a large amount of shallow gas geological disasters occur in coastal soft soil on a coastline in the southeast sea of China. For example, in the construction of the Hangzhou bay bridge, shallow air eruption accidents are encountered for many times; shallow layer gas eruption is also frequently encountered in the construction process of Hangzhou subway No. 1 line.

At present, the most effective method for dealing with the shallow gas is to release the shallow gas in advance in the process of the previous investigation, the shallow gas release adopted in Hangzhou is uncontrolled deflation at present, the deflation technology can cause great disturbance to the stratum, and from the previous ground surface displacement monitoring result, the uncontrolled deflation often causes overlarge ground surface settlement and harms the health of surrounding buildings. The problem of excessive disturbance can be effectively solved by controlled air release.

And the early prediction of the location of the shallow reservoir is the key to early deflation. The existence of shallow gas can often cause the mechanical parameters of the surrounding stratum to change, and the position of the shallow gas reservoir can be judged and obtained by pressing a probe into the soil body in-situ mechanical parameters such as cone tip resistance, side wall frictional resistance, pore water pressure and the like in the stratum. Meanwhile, the methane concentration of the shallow gas is an index for evaluating the shallow gas, but at present, the methane concentration is obtained through indoor tests after the gas is collected on site, and the detection of the methane concentration on site is less. In shallow gas formations, the shallow gas deflation process and the in-situ survey process are separated, which greatly increases the workload of shallow gas deflation and survey. The integrated equipment for controlled deflation of shallow gas and in-situ exploration is yet to be developed.

Disclosure of Invention

The invention aims to provide a self-adaptive air release rod and shallow air controlled air release recovery system and method aiming at the defects of the prior art.

The invention adopts the following technical scheme: a self-adaptive air release rod comprises a second hollow probe rod and a first hollow probe rod; the second hollow probe rod is connected to the lower part of the first hollow probe rod, and the diameter of the second hollow probe rod is larger than that of the first hollow probe rod; a groove along the circumferential direction is formed in the middle of the second hollow probe rod, a sliding sleeve is arranged in the groove, and the lower end of the sliding sleeve is wedge-shaped; the upper part of the groove is provided with an air vent, the sum of the lengths of the sliding sleeve and the air vent is less than the length of the groove, and the length of the sliding sleeve is greater than the length of the air vent; in the insertion process of the self-adaptive air bleed rod, the sliding sleeve slides to the upper part of the groove to cover the air bleed hole; when the sliding sleeve is pulled up, the sliding sleeve slides to the lower part of the groove, the air vent is exposed, and air is released through the air vent.

Further, the air release holes are waist holes which are vertically arranged. The waist hole can increase the deflation area on one hand and can reduce the excessive reduction of the rigidity of the probe rod containing the hollow core on the other hand.

The invention also provides a shallow air controlled deflation recovery method based on soil layer mechanics parameter measurement, which is realized based on the self-adaptive deflation rod and comprises the following steps:

(1) Inserting the self-adaptive air bleed rod into a shallow-layer-contained gas soil layer, and simultaneously collecting penetration cone tip resistance, side wall frictional resistance and pore water pressure of the soil layer at the insertion position;

(2) And (3) identifying the gas-containing sandy lens body according to the penetration cone tip resistance, the side wall frictional resistance and the pore water pressure collected in the step (1).

(3) and further inserting a self-adaptive air release rod, and identifying the air-containing sandy lentis in real time until the depth of the soil layer without the air-containing sandy lentis or the depth of the building foundation.

(4) The self-adaptive air release rod is pulled upwards to release shallow air.

Further, the method controls the air release speed through a gas mass flow controller, and the gas mass flow controller is communicated with the central hole passages of the second hollow probe rod and the first hollow probe rod through pipelines.

Furthermore, after the mud and water in the gas-cement mixture discharged from the central hole channels of the second hollow probe rod and the first hollow probe rod are separated by the separating device, the gas is input into the gas mass flow controller.

Further, the method also comprises the recovery of gas, specifically: the gas flowing out of the gas mass flow controller is pressurized by a supercharger and then is input into a gas storage tank.

The invention also provides a shallow gas controlled deflation recovery system based on soil layer mechanics parameter measurement, which comprises the self-adaptive deflation rod, a hydraulic loading system for inserting the self-adaptive deflation rod, an in-situ investigation system for acquiring the penetration cone tip resistance, the side wall friction resistance and the pore water pressure at the insertion position of the self-adaptive deflation rod, a gas-water-cement separation system for separating the gas-cement mixture discharged by the self-adaptive deflation rod, a gas flow servo system for controlling the gas release rate of the self-adaptive deflation rod and a gas recovery system for gas recovery.

The hydraulic loading system can comprise a reaction anchor, a hydraulic loading head, a fixing hole, a reaction frame and the like, wherein the reaction anchor is buried underground to provide reaction force for the device, the fixing hole is used for ensuring the vertical driving-in of the hollow probe rod, the reaction frame is used for applying vertical pressure to the probe rod to press the probe rod into the stratum, and the whole body is used for ensuring the vertical driving-in of the probe rod.

Furthermore, the in-situ exploration system can comprise a circular cone tip, a deformation column, a friction barrel, a pressure sensor, a pore pressure sensor, a permeable stone, a circuit pipe, a battery pipe, a hollow probe rod and the like, wherein an auxiliary pressure sensor is arranged at the joint of the circular cone tip and the pore probe rod to realize the measurement of the resistance of the cone tip when the probe is pressed into the soil body, a main pressure sensor is arranged above the friction barrel, the side wall friction force in the process of pressing down the probe rod can be obtained through the difference value of the main pressure sensor and the auxiliary pressure sensor in the pressing down process, the permeable stone and the pore pressure sensor are arranged at the cone shoulder, the permeable stone is used for preventing mud and water from blocking the pore pressure sensor, the pore pressure sensor is used for measuring the pore pressure in the pressing down process, the cone shoulder resistance, the side wall friction resistance and the pore pressure can be obtained through the in-situ press-in test, and the in-situ soil body mechanical, the upper part of the device is connected with an in-situ storage system to realize wireless acquisition of in-situ parameters of the soil body, and the upper part of the device is connected with a battery tube for supplying power to a sensor at the lower end and a storage element.

The gas flow servo system can comprise a gas mass flow controller, a mobile power supply, a transformer, a notebook computer and the like, wherein the gas mass flow meter is connected with a gas outlet at the top of the sedimentation tank, the mobile power supply and the transformer supply power to the gas mass flow meter, the gas mass flow meter is connected with the notebook computer, and the notebook computer is used for setting the maximum allowable gas release rate and acquiring the superficial gas release rate in real time.

Gas, water, mud piece-rate system include the sedimentation tank, the barometer, the bottom air inlet, the top gas outlet, arrange the silt mouth, methane concentration detection probe etc. the probe rod passes through the bottom air inlet valve of trachea and sedimentation tank and connects, top gas outlet and gas servo pass through the trachea and connect, the barometer is connected to the sedimentation tank top, barometer and data acquisition appearance are connected, an atmospheric pressure for read in real time and store the atmospheric pressure of shallow gas reservoir, sedimentation tank internally mounted has methane concentration test probe, a methane concentration for real-time supervision and gather in the shallow gas.

The gas recovery system comprises a supercharger and a gas storage tank, wherein the inlet section of the supercharger is connected with the outlet end of the gas mass flow controller, the supercharger is used for increasing the pressure of gas, and the supercharged gas enters the gas storage tank to realize the recycling of methane gas.

The invention has the beneficial effects that:

1. The self-adaptive air release rod is adopted, the problem that the rod is blocked by sludge in the traditional shallow air release technology is solved, and on the other hand, the integrated design is adopted, the problem that a probe of the traditional air release method (probe separation type) cannot be recycled is solved, the cost of shallow air release is reduced, and the self-adaptive air release rod is suitable for industrial application.

2. The ground surface sedimentation can be caused by the too fast release rate of shallow layer gas, and the ground surface sedimentation can be effectively controlled by adopting controlled deflation. The shallow layer gas is recycled, on one hand, the pollution of methane to air is avoided, and on the other hand, the shallow layer gas is effectively recycled as a resource.

drawings

FIG. 1 is a schematic structural diagram (front view) of a shallow air controlled deflation recovery system based on soil mechanics parameter measurement according to the invention;

FIG. 2 is a schematic structural view (front view) of an in-situ survey system;

FIG. 3 is a schematic (front view) of an in-situ controlled bleed system configuration;

FIG. 4 is a schematic illustration of the cement separation system configuration (elevation);

FIG. 5 is a schematic view (sectional view) of the structure of the sedimentation tank;

The system comprises an in-situ exploration system 1, a circuit pipe 2, a battery pipe 3, a self-adaptive air release rod 4, a reaction anchor 5, a tie 6, a fixing hole 7, a reaction frame 8, a control system 9, a three-way valve 10, a valve 11, a sedimentation tank 12, a bottom air inlet 13, a storage battery 14, a transformer 15, a top air outlet 16, a top air outlet 17, a notebook computer 18, a gas mass flow controller 18, a flowmeter air outlet 19, a silt discharge outlet 20, a booster 21, a booster 22, an air storage tank 23, a sliding sleeve 24, a reducing joint 25, a barometer 26, a methane concentration sensor 27, a circular cone tip 28, a permeable stone 29, a pore pressure sensor 30, a friction cylinder 31, a deformation column 32, a pressure sensor 33, a waterproof rubber pad 33, a hot plug joint I35, a hot plug joint II 36, a hot plug joint II, a hot plug joint 36, 37. The device comprises an electric wire, 38 air release holes, 39 a second hollow probe rod, 40 a first hollow probe rod, 41 a data acquisition instrument and 42 an internal thread interface.

Detailed Description

The invention provides a self-adaptive air release rod, which comprises a second hollow probe 39 and a first hollow probe 40 as shown in fig. 3; the second hollow probe 39 is connected to the lower part of the first hollow probe 40, and the diameter of the second hollow probe 39 is larger than that of the first hollow probe 40; a groove along the circumferential direction is formed in the middle of the second hollow probe 39, a sliding sleeve 23 is arranged in the groove, and the lower end of the sliding sleeve 23 is wedge-shaped; the upper part of the groove is provided with an air vent 38, the sum of the lengths of the sliding sleeve 23 and the air vent 38 is less than the length of the groove, and the length of the sliding sleeve 23 is greater than the length of the air vent 38; in the process of inserting the self-adaptive deflation rod, the sliding sleeve 23 slides to the upper part of the groove due to the friction of the side wall, and the deflation hole 38 is covered; during the process of pulling up, the sliding sleeve 23 slides to the lower part of the groove, the air vent 38 is exposed, and air is released through the air vent. The self-adaptive air release rod can prevent sludge from blocking the rod, and can be widely applied to the fields of exploration (in-situ collection of underground water), oil exploitation and the like.

Preferably, the air release holes 38 are waist holes arranged vertically.

based on the self-adaptive air release rod, the invention provides a device capable of simultaneously realizing soil layer mechanical parameter measurement, methane concentration prediction and shallow layer air controlled air release recovery, and referring to fig. 1, the device comprises the self-adaptive air release rod, a hydraulic loading system for inserting the self-adaptive air release rod, an in-situ investigation system for acquiring the penetration cone tip resistance, the side wall friction resistance and the pore water pressure at the insertion position of the self-adaptive air release rod, an air-water-cement separation system for separating air-cement mixtures released by the self-adaptive air release rod, an air flow servo system for controlling the air release rate of the self-adaptive air release rod and an air recovery system for air recovery.

The in-situ investigation system is shown in fig. 2 and comprises a circular cone tip 27, a permeable stone 28, a pore pressure sensor 29, a friction cylinder 30, a deformation column 31, a pressure sensor 32, a rubber pad 33, a first hot plug joint 34, a second hot plug joint 35, a circuit pipe 2, a battery pipe 3, an outer sleeve 36 and the like. The pore pressure sensor 29 is arranged on the inner side of the permeable stone 28 and is arranged at the top of the circular conical tip 27, the deformation column 31 is arranged inside the friction cylinder 30, the rubber pad 33 is arranged on the top end of the friction cylinder 32, the pressure sensor 33 is arranged on the inner side of the rubber pad 33, the circuit pipe 2 and the in-situ exploration probe 1 are connected through a first hot plug connector 34, the circuit pipe 2 and the battery pipe 3 are connected through a second hot plug connector 35, and the top of the battery pipe 3 is welded with threads to be connected with a shallow gas in-situ deflation system through a connector.

The self-adaptive air bleed rod is connected with the in-situ investigation system through a reducing joint 24 at the bottom;

The servo loading system comprises a reaction anchor 5, a sleeper 6, a fixing hole 7, a reaction frame 8, a control system 9, a three-way valve 10 and a valve 11. As shown in fig. 4 and 5, the gas-water-sludge separation system includes a sedimentation tank 12 and a data acquisition instrument 41; the sedimentation tank comprises a bottom air inlet 13, a sludge discharge port 20 and a top air outlet 16. Wherein reaction anchor 5 buries in the underground, for servo provides the counter-force, self-adaptation air release rod 4 passes through fixed orifices 7 to be fixed in preset position, and sleeper 6 is installed and is used for providing the support for servo in the bottom of reaction frame, and control system 9 is used for controlling servo pressure, and three-way valve 10 is installed at the top of first hollow probe rod 40, and valve 11 is connected to the upper end, and the trachea is connected to the right-hand member, and the other end that connects the trachea is connected to bottom air inlet 13 on the sedimentation tank 12. Install methane concentration sensor 29 in the sedimentation tank 12, the barometer 25 is installed at the top, and methane concentration sensor 26 is used for monitoring methane concentration, and barometer 25 and data acquisition instrument 41 are connected for monitoring and save shallow layer gas pressure. When shallow gas is led into a sedimentation tank 12 in the gas-water-sludge separation system through a three-way valve 11 by controllably releasing sprayed gas, water and sludge through a self-adaptive gas release rod, the gas enters an airflow servo system from a top gas outlet 16, and when water and sludge are accumulated to a certain amount, the gas is discharged out of the sedimentation tank 12 through a sludge discharge port 20. When the first hollow probe rod 40 is blocked by sludge, high-pressure air can be blown into the first hollow probe rod by an air compressor through the upper end of the three-way valve 10 to dredge the first hollow probe rod 40, so that the self-adaptive air release rod can recover normal operation.

The gas flow servo system comprises a gas mass flow controller 18, a storage battery 14, a transformer 15, a notebook computer 17 and the like. Wherein, the gas outlet 16 at the top of the sedimentation tank 12 is connected to a gas mass flow meter 18 through a pipeline, and the gas mass flow meter 18 controls the gas discharging speed to realize the controlled gas discharging of the whole device. The accumulator 14 and transformer 15 combine to power a gas mass flow controller 18, with a laptop computer 17 controlling the allowable flow. In order to observe the flow characteristics, the gas quality controller can be replaced by a gas mass flowmeter, and a computer is used for collecting gas flow data in real time.

When the released gas is pure, the gas mass flow controller 18 can be directly communicated with the central pore passages of the second hollow probe 39 and the first hollow probe 40 through pipelines without connecting a gas-cement separation system, so that the gas mass flow controller 18 can control the gas release speed.

in addition, the gas recovery system is composed of a supercharger 21 and a gas storage tank 22, wherein the gas inlet of the supercharger 21 is connected with the gas outlet of the gas mass flow meter 18, the gas outlet is connected with the gas storage tank 22, and the gas released from the hole of the gas mass flow meter 18 is pressed into the gas storage tank 22 for storage after the gas pressure is increased to a certain value through the supercharger 21.

The test procedure using the apparatus of the invention is briefly described below:

Firstly, the self-adaptive air release rod 4 is connected with an in-situ survey system through a reducing joint 24 at the bottom, the in-situ survey system is connected with a computer, and after an instruction is sent, the in-situ survey system starts to acquire penetration cone tip resistance, side wall friction resistance and pore water pressure data and identify a gas-containing sandy lens body; the self-adaptive air bleed rod hydraulic loading system fixes the position of the fixed hole 7.

and secondly, the self-adaptive air release rod 4 of the hydraulic loading system is pressed down, and the air-containing sandy lentis are identified in real time until the depth of the soil layer without the air-containing sandy lentis or the depth of the building foundation. In the embodiment, each probe rod is 1 meter long, so that the probe rod is pressed down for 1 meter each time until the probe rod is pressed into the position with the depth of 35 meters.

And thirdly, starting to pull up the probe rod, observing whether the rod end is sprayed with gas, water and mud, and connecting the three-way valve 11 with the valve 10 to be connected into a sedimentation tank 12 of the gas flow servo system when the spray occurs. The gas pressure value and the methane concentration value are detected by the gas pressure meter 25 and the methane concentration sensor 29 and the gas flow rate is controlled by the gas mass flow meter 18, and the gas is recovered using the gas recovery system.

And fourthly, when the airflow is reduced to 0, the three-way valve is disconnected, the probe rod continues to be pulled upwards, and when shallow air occurs again, the third step is repeated until the probe rod is completely pulled up.

disassembling the equipment and preparing the controlled air release of the next hole.

After the test, each system was isolated and the next set of tests was prepared.