CN104100293B - Integrated device and method for gas drainage borehole leak detection and plugging - Google Patents

Abstract

The invention discloses a gas extraction drilling leak detection and leak stoppage integrated device, which comprises a hole sealing pipe, a quick-connection tee joint, a detection pipe, a gas analyzer, an extraction pipe, a compressed air injection pump and an injection pipe, wherein the detection pipe and the injection pipe are arranged in the quick-connection tee joint; also discloses a method for utilizing the device, which mainly comprises the steps of gas extraction, borehole leak detection and borehole leak stopping; the device simple structure, installation and testing process are convenient, detect the precision height, and safe and reliable has effectually improved the operating efficiency.

Description

Integrated device and method for gas drainage borehole leak detection and plugging

technical field

The invention belongs to the field of coal gas drainage, and in particular relates to an integrated device and method for leak detection and plugging of gas drainage boreholes.

Background technique

Coal occupies an absolutely dominant position in my country's primary energy structure. It is estimated that by 2015, my country's coal demand will reach 3.8 billion tons. However, under the new situation, the development of my country's coal industry is facing severe challenges. The frequent occurrence of serious and extraordinarily serious gas disasters has become the most serious restrictive factor for the safe production of coal mines. The occurrence conditions of coal seams in my country are complex, high gas and coal and gas outburst mines account for about 1/3, and the prevention and control of coal mine gas disasters has become the top priority of safe production. In addition, gas (coal bed methane) is a clean and efficient energy source. Under the environment of high international oil prices and unprecedented pressure to reduce emissions, it is urgent to increase the development and utilization of gas as a means of optimizing my country's energy structure. important resource. Gas drainage is not only a regional measure to effectively prevent and control coal mine gas disasters and realize safe and essential production, but also the main technical means to implement coalbed methane development in coal mining areas in my country. The extraction and utilization of coal mine gas is not only conducive to improving the safety level of coal mines, but also conducive to increasing energy supply, optimizing energy structure, improving energy utilization efficiency, promoting energy conservation and emission reduction, and protecting the ecological environment.

Therefore, coal mine methane extraction safety, energy and environmental protection benefits in one, serve multiple purposes, have multiple economic and social benefits, and have great practical significance for my country's economic and social development. Due to the complex geological conditions of coal seam gas in my country and the influence of the current technical level, the sealing quality of underground drainage boreholes is poor, resulting in generally low gas concentration in coal seam borehole drainage. This not only poses a threat to the safety of the underground gas transportation system in coal mines, but also increases the utilization cost of gas drainage, which seriously hinders the rapid and good development of my country's coalbed methane development industry. Aiming at the problem of drainage drilling sealing method, Chinese scholars and field technicians have put into a lot of practice, successively formed the grouting sealing technology, polyurethane polymer material sealing technology, fly ash secondary sealing Technology, etc. The application of this kind of technology has achieved certain application effects in different mining areas. However, due to the existence of the "pressure relief circle" formed by the tunneling of coal mine underground roadway and the creep behavior of coal rock itself, the drilling After the initial sealing is completed, with the implementation of the drainage operation, it will lead to the development of secondary fractures, which will lead to air intake into the borehole and reduce the concentration of the gas extracted in the borehole.

Contents of the invention

In view of this, the object of the present invention is to provide an integrated device and method that has a simple structure and can complete gas drainage, drilling leak detection and plugging without replacing operating equipment.

In order to achieve the above purpose, the present invention provides the following technical solutions: an integrated device for leak detection and plugging of gas drainage boreholes, including a sealing tube, a quick-connect tee, a detection tube, a gas analyzer and a gas extraction tube, and It includes a compressed air injection pump and an injection pipe. The detection pipe and the injection pipe are built in the quick-connect tee, the first port of the quick-connect tee is set outside the injection pipe, and the second port is connected to the extraction pipe, the third port is connected with the sealing pipe, the outlet end of the injection pipe extends into the extraction borehole, the inlet end is connected with the compressed air injection pump, and the first port of the quick-connect tee The opening and closing valve I for controlling the opening and closing of the injection pipe and the opening and closing valve II for controlling the opening and closing of the extraction pipe are correspondingly arranged at the first port and the second port.

Further, there are four injection pipes built into the quick-connect tee, the angle between two adjacent injection pipes is 90°, and the outlet ends of each injection pipe are curved arcs.

Further, the detection pipe is arranged among the four injection pipes, and the detection end of the detection pipe protrudes from the outlet end of the injection pipe.

Further, the third port of the quick-connect tee is a ferrule structure, and the ferrule structure is provided with a tapered washer fitted outside the injection pipe.

The present invention also provides a method for utilizing a gas drainage borehole leak detection and plugging integrated device, which mainly includes the following steps:

(1) Gas extraction: close the on-off valve I, open the on-off valve II, and connect the sealing pipe and the extraction pipe for gas extraction;

(2) Borehole leak detection: When the gas concentration in the borehole is found to be low, open the on-off valve II and the valve on the detection pipe to detect the concentration of oxygen or nitrogen gas at different depths in the borehole to determine the location of the gas leak;

(3) Drilling plugging: close the on-off valve II and the valve on the detection pipe, open the on-off valve I and the compressed air injection pump, so that the plugging material is sprayed from the injection pipe to the inner wall of the drilled hole at the location of the air leakage superior.

The beneficial effects of the present invention are: (1) under the state of gas extraction, the oxygen or nitrogen concentration measurement at different depths in the extraction borehole can be carried out synchronously, and the gas concentration can be detected in real time during the extraction process, so as to detect the leakage in time; Plugging and sealing the gas, effectively increasing the concentration of gas extraction; (2) If there is a gas leakage problem, it will cause the concentration of oxygen or nitrogen to increase, causing potential safety hazards. Through timely leak detection and plugging, it can be effectively Guarantee the safety of the drainage borehole; (3) Simple structure, easy to use, high detection accuracy, safe and reliable, can complete the leak detection and plugging operation of gas drainage and drainage borehole without changing the operation equipment, effective Improved work efficiency.

Description of drawings

In order to make the purpose, technical scheme and beneficial effect of the present invention clearer, the present invention provides the following drawings for illustration:

Fig. 1 is a structural representation of the present invention;

Fig. 2 is an enlarged view of part A of Fig. 1 .

detailed description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in the figure, the gas drainage borehole leak detection and plugging integrated device according to the present invention includes a sealing pipe 1, a quick connection tee 2, a detection pipe 3, a gas analyzer 4 and a drainage pipe 5, It also includes a compressed air injection pump 6 and an injection pipe 7. The detection pipe 3 and the injection pipe 7 are built into the quick-connect tee 2, and the first port 21 of the quick-connect tee 2 is arranged on the injection pipe. 7, the second port 22 is connected to the extraction pipe 5, the third port 23 is connected to the sealing pipe 1, the discharge port end of the injection pipe 7 extends into the extraction borehole 8, and the feed port end is connected to the extraction borehole 8. The compressed air injection pump 6 is connected, and the first port 21 and the second port 22 of the quick-connect tee 2 are correspondingly provided with an opening and closing valve I24 for controlling the opening and closing of the injection pipe 7 and a valve for controlling the opening and closing of the extraction pipe 5. On-off valve II 25.

In this embodiment, the three ports of the quick-connect tee 2 are respectively sealed and connected with the injection pipe 7, the extraction pipe 5 and the sealing pipe 1, and the opening and closing valve I24 and the opening and closing valve II25 control the injection pipe and the extraction pipe. The opening and closing of the pipe, the opening and closing of the detection pipe 3 is independently controlled by the valve 9 set on the detection pipe 3 (connected with the gas analyzer), by selectively opening or closing the flow of the extraction pipe 5 and the injection pipe 7 path, realize gas drainage and drilling plugging, and then control the opening and closing of the detection pipe 3 to realize drilling leak detection; the overall device structure is simple, easy to install, and can meet different operation requirements.

As a further improvement of the above scheme, four injection pipes 7 are built in the quick-connect tee 2, and the angle between two adjacent injection pipes 7 is 90°. The mouth and ends are all curved arcs; the leaking position is blocked in a dispersed manner, which ensures the reliability of the plugging, and the design of the curved discharge port is more conducive to the contact between the plugging material and the inner wall of the borehole; component of epoxy resin.

In this embodiment, the detection tube 3 is arranged in the middle of the four injection tubes 7, and the detection end of the detection tube 3 protrudes from the outlet end of the injection tube 7, so that the detection tube 3 can be stabilized by the injection tube 7 At the same time, it can also avoid the detection accuracy of the detection pipe 3 being affected by the spraying of the injection pipe 7; the third port 23 of the quick-connect tee 2 is a ferrule structure, and the ferrule structure is provided with a The outer tapered gasket 26; the connection and sealing of the third port 23 on the quick-connect tee 2 can be realized by tightening the ferrule structure, the operation is simple and fast, and the sealing is reliable.

The present invention also provides a method for gas drainage, drilling leak detection and plugging using the above-mentioned integrated device, which mainly includes the following steps:

(1) Insert the integrated device into the extraction borehole 8, and connect each connection end of the device with the extraction pipe 5, the compressed air injection pump 6, the gas analyzer 4 and the sealing pipe 1 to ensure that each The connection end is tight and reliable. At this time, the opening and closing valve I24, the opening and closing valve II25 on the quick-connect tee 2 and the valve 9 on the detection pipe 3 are all closed; In the closed state, open the on-off valve II 25 to connect the sealing pipe 1 and the drainage pipe 5 to realize gas drainage.

(2) When the inspection operation finds that the gas concentration of the borehole drainage is low, it is necessary to carry out leak detection on the drainage borehole 8. The hole pipe 1 is connected with the extraction pipe 5, the valve 9 on the detection pipe 3 is opened, the gas concentration values at different hole depths are measured by the gas analyzer 4, the oxygen or nitrogen gas concentration values at different depths in the borehole are detected, and the leakage is judged. The gas position; the valve 9 on the detection pipe 3 can also be kept in a normally open state, which is convenient for real-time monitoring of gas concentrations at different depths during the gas extraction process.

(3) After the air leakage location is found, plug the air leakage location. At this time, the on-off valve II22 and the valve 9 on the detection pipe 3 should be closed, the on-off valve I21 and the compressed air injection pump 6 should be opened, and the downhole compression Air, through the compressed air injection pump 6 and the injection pipe 7, the plugging material is injected into the air leakage position on the inner wall of the borehole, thereby realizing the plugging of the borehole.

Its working principle is: under the condition that the sealing quality of the borehole is good and there is no air leakage around the borehole, the distribution of the concentration of oxygen or nitrogen in the extraction borehole 8 along the depth of the borehole should be basically stable and consistent (that is, within a small range Fluctuation); if the sealing quality of the borehole is poor or there is an air leakage problem at a certain position inside the borehole, under the action of negative pressure in the extraction, the concentration of oxygen or nitrogen in the extraction borehole 8 will have a sudden change along the distribution of the hole depth. The location is the location of the air leakage, so the location of the air leakage can be determined according to the change of the measured value of the concentration of oxygen or nitrogen; gas position, so as to implement the integration of leak detection and plugging of drainage boreholes.

Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that it can be described in terms of form and Various changes may be made in the details without departing from the scope of the invention defined by the claims.

Claims (5)

1. An integrated device for gas drainage borehole leak detection and plugging, including a sealing pipe, a quick-connect tee, a detection pipe, a gas analyzer and a gas extraction pipe, characterized in that it also includes a compressed air injection pump And the injection pipe, the detection pipe and the injection pipe are built in the quick-connect tee, the first port of the quick-connect tee is set outside the injection pipe, the second port is connected with the extraction pipe, and the third port Connected with the sealing pipe, the outlet end of the injection pipe extends into the extraction borehole, the inlet end is connected with the compressed air injection pump, the first port and the second port of the quick-connect tee Correspondingly, there are on-off valve I for controlling the opening and closing of the injection pipe and an on-off valve II for controlling the opening and closing of the extraction pipe. 2. The integrated device for gas drainage drilling leak detection and plugging according to claim 1, characterized in that: there are four injection pipes built in the quick-connect tee, and there is a gap between two adjacent injection pipes. The included angle is 90°, and the outlet ends of each of the injection pipes are curved arcs. 3. The integrated device for gas drainage drilling leak detection and plugging according to claim 2, characterized in that: the detection pipe is arranged in the middle of the four injection pipes, and the detection end of the detection pipe extends out of the injection pipe outlet end of the tube. 4. The integrated device for gas drainage drilling leak detection and plugging according to claim 3, characterized in that: the third port of the quick-connect tee is a ferrule structure, and the ferrule structure is equipped with a sleeve Tapered gasket outside the injection tube. 5. A leak detection and plugging method utilizing the integrated device according to any one of claims 1-4, characterized in that it mainly comprises the following steps: (1) Gas extraction: close the on-off valve I, open the on-off valve II, and connect the sealing pipe and the extraction pipe to extract gas; (2) Borehole leak detection: When the gas concentration in the borehole is found to be low, open the on-off valve II and the valve on the detection pipe to detect the concentration of oxygen or nitrogen gas at different depths in the borehole to determine the location of the gas leak; (3) Drilling plugging: close the on-off valve II and the valve on the detection pipe, open the on-off valve I and the compressed air injection pump, so that the plugging material is sprayed from the injection pipe to the inner wall of the drilled hole at the location of the air leakage superior.