阅读说明：本技术 天然气井井筒井漏三维堵漏方法及其试验装置 (Three-dimensional leakage stoppage method for natural gas well shaft leakage and test device thereof ) 是由 黄有为 于 2019-10-23 设计创作，主要内容包括：本发明提供天然气井井筒井漏三维堵漏方法及其试验装置,堵漏方法PPS聚合物凝胶、T&TS液体、柔弹性、高滤失水泥浆堵漏材料及超低渗透、微泡等技术材料的开发与应用,解决了许多井漏技术难题。试验装置包括岩心夹持器,所述岩心夹持器的前端通过中间容器连接有恒流/压泵,所述岩心夹持器的后端依次通过流量计、回压阀与气瓶连接,所述中间容器、岩心夹持器设置在加热系统内部,所述岩心夹持器连接有围压系统,所述岩心夹持器的前端设置有压力传感器一,所述岩心夹持器的后端设置有压力传感器二,所述压力传感器一、压力传感器二与数据采集系统连接,所述岩心夹持器的前端和后端通过设置有手动阀一的旁路管道连接,可以直观的看到及证明NZ浆的封堵效果。(The invention provides a natural gas well shaft leakage three-dimensional plugging method and a test device thereof, and the plugging method is the development and application of PPS polymer gel, T & TS liquid, flexible and elastic high-filtration cement slurry plugging materials, ultra-low permeability, micro bubbles and other technical materials, thereby solving a plurality of technical problems of leakage. The testing device comprises a rock core holder, the front end of the rock core holder is connected with a constant-current/pressure pump through an intermediate container, the rear end of the rock core holder is connected with a gas cylinder through a flowmeter and a back-pressure valve in sequence, the intermediate container and the rock core holder are arranged inside a heating system, the rock core holder is connected with a confining pressure system, the front end of the rock core holder is provided with a first pressure sensor, the rear end of the rock core holder is provided with a second pressure sensor, the first pressure sensor and the second pressure sensor are connected with a data acquisition system, the front end and the rear end of the rock core holder are connected through a bypass pipeline provided with a first manual valve, and the plugging effect of NZ slurry can be visually seen and proved.)

1. A three-dimensional leakage stopping method for natural gas well shaft leakage is provided, when the leakage speed is less than or equal to 5m³When the plugging is carried out for the time of the drilling, the drilling is carried out by adopting a row-descending drilling mode, a deep small borehole is adopted, the density is reduced, the viscosity is reduced, and the plugging is carried out in a mode of along-drilling;when the lost circulation velocity is 5-15m³When the plugging is carried out for the time of the drilling, a row-lowering drilling mode is adopted, a deep small borehole is adopted, the density is reduced, the viscosity is reduced, the cutting is reduced, and the plugging is carried out in a plugging mode while drilling and through a high-water-loss plugging agent or bridging slurry; when the lost circulation velocity is 15-30m³When the plugging agent is used for plugging the well, a deep small well is adopted, the discharge capacity, the density and the viscosity are reduced, and the plugging is performed in a plugging mode while drilling and through a high-water-loss plugging agent or bridging slurry; when the lost circulation velocity is 30-60m³In the hour of the construction process, bridge slurry plugging and cement slurry plugging are adopted; when the lost circulation speed is more than or equal to 60m³And in the hour, adopting cement paste plugging or bridge slurry plugging, or adopting bridge slurry plugging and cement paste composite plugging.

2. The three-dimensional leakage stoppage test device for the natural gas well shaft leakage is characterized by comprising a core holder, wherein the front end of the core holder is connected with a constant-current/pressure pump through an intermediate container, the rear end of the core holder is connected with a gas cylinder through a flowmeter and a back-pressure valve in sequence, the intermediate container and the core holder are arranged inside a heating system, the core holder is connected with a confining pressure system, the front end of the core holder is provided with a first pressure sensor, the rear end of the core holder is provided with a second pressure sensor, the first pressure sensor and the second pressure sensor are connected with a data acquisition system, and the front end and the rear end of the core holder are connected through a bypass pipeline provided with a first manual valve.

3. The natural gas well shaft leakage three-dimensional leakage stoppage test device as recited in claim 2, wherein a second manual valve is arranged between the constant flow/pressure pump and the intermediate container.

4. The natural gas well wellbore lost circulation three-dimensional leaking stoppage test device as recited in claim 2, wherein a third manual valve is arranged between the bypass pipeline and the first pressure sensor.

5. The natural gas well wellbore lost circulation three-dimensional leakage stoppage test device as recited in claim 2, wherein the confining pressure system comprises an air source pump, the air source pump is communicated with the core holder through a fourth manual valve, a pressure gauge is arranged between the fourth manual valve and the core holder, the fourth manual valve is connected with an external discharge pipeline, and a fifth manual valve is arranged on the external discharge pipeline.

6. The natural gas well wellbore lost circulation three-dimensional leaking stoppage test device as recited in claim 2, wherein 2% brine, NZ slurry and 2% brine are sequentially filled in the intermediate container according to a test sequence.

Technical Field

The invention particularly relates to a natural gas well shaft leakage three-dimensional plugging method and a test device thereof.

Background

When natural gas well pit shaft was adopted the natural gas, can meet the lost circulation phenomenon usually, and the lost circulation phenomenon mostly is that the fracture of stratum caused, only need when carrying out the leaking stoppage usually plug up the fracture just can, but current fracture plugging agent effect is not too good, can not audio-visually see the leaking stoppage effect moreover, also lacks such testing arrangement.

Disclosure of Invention

In order to solve the problems, the invention provides a natural gas well shaft leakage three-dimensional leakage stoppage method and a test device thereof.

The technical scheme is as follows:

a three-dimensional leakage stopping method for natural gas well shaft leakage is provided, when the leakage speed is less than or equal to 5m³When the plugging is carried out for the time of the drilling, the drilling is carried out by adopting a row-descending drilling mode, a deep small borehole is adopted, the density is reduced, the viscosity is reduced, and the plugging is carried out in a mode of along-drilling; when the lost circulation velocity is 5-15m³When the plugging is carried out for the time of the drilling, a row-lowering drilling mode is adopted, a deep small borehole is adopted, the density is reduced, the viscosity is reduced, the cutting is reduced, and the plugging is carried out in a plugging mode while drilling and through a high-water-loss plugging agent or bridging slurry; when the lost circulation velocity is 15-30m³When the plugging agent is used for plugging the well, a deep small well is adopted, the discharge capacity, the density and the viscosity are reduced, and the plugging is performed in a plugging mode while drilling and through a high-water-loss plugging agent or bridging slurry; when the lost circulation velocity is 30-60m³In the hour of the construction process, bridge slurry plugging and cement slurry plugging are adopted; when the lost circulation speed is more than or equal to 60m³And in the hour, adopting cement paste plugging or bridge slurry plugging, or adopting bridge slurry plugging and cement paste composite plugging.

The utility model provides a three-dimensional leaking stoppage test device of natural gas well pit shaft lost circulation, includes the rock core holder, the front end of rock core holder is connected with constant current/pressure pump through middle container, the rear end of rock core holder loops through flowmeter, back pressure valve and is connected with the gas cylinder, middle container, rock core holder set up inside heating system, the rock core holder is connected with the confining pressure system, the front end of rock core holder is provided with pressure sensor one, the rear end of rock core holder is provided with pressure sensor two, pressure sensor one, pressure sensor two are connected with data acquisition system, the front end and the rear end of rock core holder are through being provided with the bypass pipe connection of manual valve one.

Furthermore, a manual valve II is arranged between the constant-flow/pressure pump and the intermediate container, so that the constant-flow/pressure pump can be better controlled to pump liquid into the intermediate container.

Furthermore, a manual valve III is arranged between the bypass pipeline and the pressure sensor I, so that liquid can be better controlled to enter the core holder.

Furthermore, the confining pressure system comprises an air source pump, the air source pump is communicated with the core holder through a fourth manual valve, a pressure gauge is arranged between the fourth manual valve and the core holder, the fourth manual valve is connected with an external discharge pipeline, and a fifth manual valve is arranged on the external discharge pipeline, so that the internal pressure of the stratum can be better simulated.

Furthermore, 2% saline water, NZ slurry and 2% saline water are sequentially contained in the intermediate container according to a test sequence, the channel in the pipe is filled with the 2% saline water, the permeability of the saline water is measured, then the NZ slurry is injected to displace the saline water in the simulated rock, the temperature is kept constant for more than 12 hours at the simulated temperature, when NZ is fully crosslinked, the saline water is used for displacing, the pressure and the flow are recorded, and the blocking effect of the NZ slurry can be easily seen through a data acquisition system.

The invention has the following beneficial effects:

the plugging method has good rheological property, solves the problem of matching of the rigidity and the size fraction of the solid-phase particles of the traditional plugging material, and greatly improves the bearing capacity of the leakage stratum. The plugging material adopts inert substances, does not react with water and acid gas in the stratum, and has small damage degree to the stratum. The plugging method has strong high-temperature resistance, simple field construction operation and strong economic applicability

The experimental device has a simple structure, can visually see and prove the plugging effect of the NZ slurry, the core holder clamps the simulated core, the simulated core simulates a sandstone stratum, the core is simulated by filling quartz sand in a sand filling pipe, a channel in the pipe is filled with 2% saline water, the permeability of the saline water is measured, then the NZ slurry is injected to displace the saline water in the simulated rock, the temperature is kept at the simulated temperature for more than 12 hours, the NZ is fully crosslinked, the saline water is used for displacing, the pressure and the flow are recorded, the plugging effect of the NZ slurry can be easily seen through the data acquisition system, and the heating system and the confining pressure system can better ensure that the temperature and the pressure of the simulated core can be simulated during the test.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

As shown in fig. 1, the natural gas well shaft leakage three-dimensional leakage stoppage test device comprises a core holder 1, wherein the front end of the core holder 1 is connected with a constant-flow/pressure pump 3 through an intermediate container 2, the rear end of the core holder 1 is connected with a gas cylinder 103 through a flowmeter 101 and a back-pressure valve 102 in sequence, the intermediate container 2 and the core holder 1 are arranged inside a heating system 4, the core holder 1 is connected with a confining pressure system 5, the front end of the core holder 1 is provided with a pressure sensor I6, the rear end of the core holder 1 is provided with a pressure sensor II 7, the pressure sensor I6 and the pressure sensor II 7 are connected with a data acquisition system 8, and the front end and the rear end of the core holder are connected through a bypass pipeline 10 provided with a manual valve I9. And a manual valve II 11 is arranged between the constant-flow/pressure pump 3 and the intermediate container 2, so that the constant-flow/pressure pump can be better controlled to pump liquid into the intermediate container. And a manual valve III 12 is arranged between the bypass pipeline 10 and the pressure sensor I6, so that the liquid can be better controlled to enter the core holder. The confining pressure system 5 comprises an air source pump 501, the air source pump is communicated with the core holder through a manual valve IV 502, and the manual valve isA pressure gauge 503 is arranged between the fourth valve 502 and the rock core holder, the fourth manual valve is connected with an external discharge pipeline, and a fifth manual valve is arranged on the external discharge pipeline, so that the pressure inside the stratum can be better simulated. The middle container is filled with 2% saline, NZ slurry and 2% saline in sequence according to a test sequence, a channel in the pipe is filled with the 2% saline firstly, the permeability of the saline is measured, then the NZ slurry is injected to displace the saline in a simulated rock, the temperature is kept constant for more than 12 hours at a simulation temperature, when NZ crosslinking is sufficient, the saline is displaced, the pressure and the flow are recorded, the plugging effect of the NZ slurry can be easily seen through a data acquisition system, the saline adopts 2% KCL solution, the test condition is 60 ℃, a 40-60-mesh quartz sand bed is adopted to simulate sandstone, and the test result is as follows: the initial permeability of the 2% KCL solution is 8.4D, and the permeability of the 2% KCL solution after plugging is 0.113X10^-3。

This embodiment simple structure, can audio-visually see and prove the shutoff effect of NZ thick liquid, the core of core holder centre gripping simulation, the simulated core simulates the sandstone stratum, adopt the built-in quartz sand of sand pack pipe to simulate the core, earlier with 2% salt solution full of intraductal passageway, survey the salt solution permeability, then pour into the NZ thick liquid and displace salt solution in the simulation rock, constant temperature more than 12 hours under the analog temperature, treat that the NZ cross-linking is abundant, displace with salt solution, record pressure and flow, the shutoff effect of NZ thick liquid can very easily be seen through data acquisition system, the temperature and the pressure of core can be simulated when assurance test that heating system and confined pressure system can be better.

The present invention is illustrated by way of example and not by way of limitation. It will be apparent to those skilled in the art that other variations and modifications may be made in the foregoing disclosure without departing from the spirit or essential characteristics of all embodiments, and that all changes and modifications apparent from the above teachings are within the scope of the invention.