WO2022052289A1 - 松软煤层内全长筛管护孔并具有带压封孔的装置及方法 - Google Patents

松软煤层内全长筛管护孔并具有带压封孔的装置及方法 Download PDF

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Publication number
WO2022052289A1
WO2022052289A1 PCT/CN2020/127434 CN2020127434W WO2022052289A1 WO 2022052289 A1 WO2022052289 A1 WO 2022052289A1 CN 2020127434 W CN2020127434 W CN 2020127434W WO 2022052289 A1 WO2022052289 A1 WO 2022052289A1
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Prior art keywords
hole
pipe
grouting
fixed
sealing
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PCT/CN2020/127434
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English (en)
French (fr)
Inventor
倪冠华
董凯
程卫民
谢景娜
王刚
刘义鑫
黄启铭
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山东科技大学
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Priority to US17/596,840 priority Critical patent/US11396810B2/en
Publication of WO2022052289A1 publication Critical patent/WO2022052289A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00—Materials not provided for elsewhere
    • C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • C04B24/24—Macromolecular compounds
    • C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B24/2641—Polyacrylates; Polymethacrylates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C04B28/04—Portland cements
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/24—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing alkyl, ammonium or metal silicates; containing silica sols
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/24—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing alkyl, ammonium or metal silicates; containing silica sols
    • C04B28/26—Silicates of the alkali metals
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/12—Packers; Plugs
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/006—Production of coal-bed methane
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/02—Subsoil filtering
    • E21B43/08—Screens or liners
    • E21B43/082—Screens comprising porous materials, e.g. prepacked screens
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/02—Subsoil filtering
    • E21B43/08—Screens or liners
    • E21B43/086—Screens with preformed openings, e.g. slotted liners
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F7/00—Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00008—Obtaining or using nanotechnology related materials
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00034—Physico-chemical characteristics of the mixtures
    • C04B2111/00137—Injection moldable mixtures
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00663—Uses not provided for elsewhere in C04B2111/00 as filling material for cavities or the like
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00724—Uses not provided for elsewhere in C04B2111/00 in mining operations, e.g. for backfilling; in making tunnels or galleries
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00—Materials not provided for elsewhere
    • C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2003/1034—Materials or components characterised by specific properties
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00—Materials not provided for elsewhere
    • C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2003/1087—Materials or components characterised by specific uses

Definitions

  • the invention relates to the technical field of gas extraction, in particular to a device and method for protecting a hole with a full-length screen tube in a soft coal seam and having a pressure-sealed hole.
  • coal mining due to the complex and changeable coal seam occurrence conditions, coal disasters are frequent, and gas accidents are serious.
  • Coalbed methane is an associated mineral resource of coal. It is an unconventional natural gas. It is also a clean and high-quality energy and chemical raw material.
  • the rational use of mine gas is of great significance to reducing mine gas accidents and protecting the environment.
  • Gas drainage is a simple and efficient method to solve gas outburst, among which drilling drainage is the most widely used.
  • the large mining depth, high stress release, transfer and strong load cause the coal and rock mass to be broken, and the large-scale mining has repeatedly disturbed the coal and rock mass, so that the coal and rock mass has experienced many times.
  • the hole wall structure of the drilled hole is unstable due to shear damage and tensile damage, and the gas drainage hole is easy to collapse, especially In front of the working face, the two stress concentration sections of the roadway and the local structural stress concentration section are easy to collapse and block in a short period of time, which greatly reduces the effective drainage time of the drilling gas drainage hole and seriously affects the drilling gas drainage. Therefore, it is necessary to further improve the existing gas extraction device and extraction method.
  • the present invention provides a full-length screen pipe protecting hole in a soft coal seam with belt pressure
  • the device and method for sealing holes, the specific technical scheme is as follows.
  • a device for protecting a hole with a full-length screen pipe in a soft coal seam and having a pressure-sealed hole comprising a extraction pipe, a sealing plug, a grouting pressure pump, a grouting pipe and a grouting pipe, and a plurality of fixed-hole screen pipes and a plurality of metal baffles;
  • the fixed-hole screen pipes are fixed to the hole wall of the gas drainage borehole through the metal baffles, and the plurality of fixed-hole screen pipes are connected and fixed in sequence;
  • the sealing plugs are arranged on the gas drainage boreholes The orifice section of the grouting, a sealed space is formed between the two sealing plugs;
  • the grouting pressure pump is connected with the grouting pipe, the grouting pipe extends into the sealed space, and the grouting pipe is communicated with the sealed space;
  • the extraction pipe Pass through sealed spaces as well as solid hole screens and metal baffles.
  • one end of the fixed-hole screen tube is provided with a bayonet, and the other end is provided with a buckle; the bayonet and the buckle cooperate with each other.
  • a plurality of ventilation holes are evenly arranged on the metal baffle and the fixed-hole screen; the center of the metal baffle and the center of the sealing plug are provided with a extraction port, and the diameter of the extraction pipe is equal to the extraction port aperture.
  • both ends of the fixed-hole screen are provided with sealing rings.
  • the sealed space is filled with a pressurized sealing material
  • the composition of the pressurized sealing material is Portland cement, nano-silica, sodium silicate, styrene-acrylic emulsion and water.
  • a gas extraction method with a full-length screen tube protecting holes and having pressure-sealing holes in a soft coal seam using the above-mentioned device for protecting a full-length screen tube holes and having pressure-sealing holes in a soft coal seam, the steps include:
  • a sealing plug is connected to the inner side of the orifice section of the gas drainage hole, and the sealing plug and the metal baffle are closely attached;
  • a sealing plug is set at the orifice of the gas drainage borehole, and a sealing space is formed between the two sealing plugs;
  • the grouting pressure pump injects the pressurized sealing material into the sealed space through the grouting pipe; when the grouting pipe is out of the grouting, the grouting is stopped;
  • the nozzle of the grouting pipe extends into the inside of the sealed space, and the nozzle of the grouting pipe extends to the outside of the sealed space.
  • the mass ratio of water and Portland cement in the pressurized sealing material is 0.4, the amount of nano-silica added is 4% of the mass of Portland cement, and the amount of sodium silicate added is Portland cement. 0.5% of the mass, the addition of styrene-acrylic emulsion is 2% of the mass of Portland cement.
  • nano-silicon dioxide, sodium silicate, and styrene-acrylic emulsion are mixed with water, and after stirring for 3 minutes, Portland cement is added, and the stirring is continued until the materials are evenly mixed.
  • the invention provides a device and method for protecting holes with a full-length screen tube in a soft coal seam and having a pressure-sealed hole.
  • the beneficial effects of the device are that the device supports the space in the drilling hole through the fixed-hole screen tube and the metal baffle, so as to ensure the extraction.
  • the sealing plug is used to form a sealed space in the orifice section of the drilling hole, and the sealing material with pressure is filled to improve the sealing effect of the drilling hole;
  • the method of using the device to complete the drilling arrangement for gas drainage has the advantages of convenient construction. ,
  • the hole protection effect is good, and the extraction efficiency is high.
  • Fig. 1 is a schematic diagram of the structure of a device with a full-length screen tube protecting holes in a soft coal seam and having a pressure-sealed hole;
  • Fig. 2 is a schematic view of the structure of a solid-hole screen
  • Figure 3 is a schematic structural diagram of a metal baffle
  • the utility model relates to a device for protecting a hole with a full-length screen tube in a soft coal seam and having a pressure-sealed hole.
  • the device includes a grouting system, a drainage system and a hole-fixing system.
  • the grouting system injects the pressure-bearing sealing material into the hole through a pressure pump.
  • the extraction pipe of the extraction system draws gas between the vent holes on the metal baffle and the fixed-hole screen, which enhances the gas circulation;
  • the fixed-hole system is positioned in the borehole and passes through the metal
  • the baffle is fixed, and the fixed-hole screen pipes are connected and fixed by bayonet and buckle; the device is installed and fixed in the gas extraction borehole, and after the hole is sealed, the extraction pipe is connected to the extraction pump for gas extraction.
  • Its structure specifically includes a drawing pipe 1 , a sealing plug 2 , a grouting pressure pump 3 , a grouting pipe 4 and a grouting pipe 5 , as well as a plurality of fixed-hole screen pipes 6 and a plurality of metal baffles 7 .
  • the grouting pressure pump 3 is arranged outside the hole of the gas drainage hole 12
  • the sealing plug 2 cooperates with the grouting pipe 4 and the grouting pipe 5 to plug the hole
  • the drainage pipe 1 passes through the solid hole screen pipe 6
  • the metal baffle 7 is fixed in the gas drainage borehole for gas drainage.
  • the fixed-hole screen pipe 6 is fixed to the hole wall of the gas drainage borehole 12 through a metal baffle, and a plurality of fixed-hole screen pipes 6 are connected and fixed end to end in sequence. Slightly smaller than the hole diameter of the gas drainage hole; the metal baffles 7 are arranged at the joints and ends of a plurality of fixed hole screens.
  • the sealing plug 2 is arranged at the orifice section of the gas drainage borehole, a sealing space 13 is formed between the two sealing plugs 2, and the sealing space 3 is filled with a sealing material under pressure to complete the sealing.
  • the grouting pressure pump 3 is connected to the grouting pipe, the grouting pipe 4 extends into the sealed space, and the grouting pipe 5 is communicated with the sealed space; the grouting pipe 4 is used to inject the sealing material under pressure into the sealed space, and the grouting pipe 5 is used for It is used to judge whether the pressurized sealing material fills the sealing space.
  • the extraction pipe 1 passes through the sealed space, the fixed-hole screen pipe and the metal baffle, and the extraction pipe 1 can be fixed along the axis of the grouting hole, so as to facilitate gas extraction.
  • One end of the hole-fixing screen tube 6 is provided with a bayonet, and the other end is provided with a buckle, and the bayonet and the buckle cooperate with each other, thereby facilitating the connection of the hole-fixing screen.
  • a plurality of ventilation holes 11 are evenly arranged on the metal baffle 7 and the solid-hole screen tube 6 to facilitate gas circulation, thereby improving the gas extraction efficiency.
  • the center of the metal baffle 7 and the center of the sealing plug are provided with extraction ports 14.
  • the diameter of the extraction pipe 1 is equal to the aperture of the extraction opening 14, so that the extraction pipe can be easily fixed.
  • Both ends of the fixed-hole screen tube 6 are provided with rubber sealing rings, so as to ensure the sealing performance of the connection position.
  • the sealed space 13 is filled with a pressure-bearing sealing material
  • the pressure-bearing sealing material is composed of Portland cement, nano-silica, sodium silicate, styrene-acrylic emulsion and water.
  • the sealing material should have good fluidity, compactness, cohesion and mechanical strength, so as to block the borehole cracks during the extraction process, eliminate or weaken the stress from around the borehole, and avoid self-deformation and breakage.
  • a gas extraction method with a full-length screen tube protecting holes and having pressure-sealing holes in a soft coal seam using the above-mentioned device for protecting a full-length screen tube holes and having pressure-sealing holes in a soft coal seam, the steps include:
  • the length of the gas drainage pipe is determined according to the length of the gas drainage hole, and the diameter of the gas drainage pipe is generally smaller than the hole diameter of the gas drainage hole.
  • the length of the fixed-hole screen is also determined according to the length of the gas drainage hole. Generally, the length of each fixed-hole screen is 1-3m.
  • the uniformly arranged ventilation holes on the fixed-hole screen can enhance the gas drainage in the gas drainage hole. circulation within.
  • a sealing plug is connected to the inner side of the orifice section of the gas drainage hole, and the sealing plug and the metal baffle are closely attached.
  • the sealing plug installed first is in close contact with the metal baffle plate on the outermost side of the hole, so as to ensure the stability of the structure in the hole.
  • the position of the hole of the hole is the outer direction, and the position from the hole to the bottom of the hole is the hole inward direction.
  • a sealing plug is set at the orifice position of the gas drainage hole, and a sealed space is formed between the two sealing plugs. Sealed structure.
  • the nozzle of the grouting pipe extends into the inside of the sealed space, so that the slurry can preferably reach the inside of the borehole, and the nozzle of the grouting pipe extends to the outside of the sealed space to ensure timely judgment of whether it is full.
  • the grouting pressure pump injects the pressurized sealing material into the sealed space through the grouting pipe; when the grouting pipe is out of the grouting, the grouting is stopped.
  • the mass ratio of water and Portland cement in the sealing material under pressure is 0.4
  • the amount of nano-silica added is 4% of the mass of Portland cement
  • the amount of sodium silicate added is 0.5% of the mass of Portland cement
  • the addition of styrene-acrylic emulsion is 2% of the quality of Portland cement.
  • the pressure sealing material When making the sealing material under pressure, first mix nano-silica, sodium silicate, styrene-acrylic emulsion with water, add Portland cement after stirring for 3 minutes, and continue stirring until the materials are evenly mixed.
  • cement-based materials such as compression resistance, shear resistance and high strength
  • the pressure sealing material solves the problems of water loss shrinkage, abundant cracks and poor sealing effect.
  • the synergistic effect of styrene-acrylic emulsion, silica and sodium silicate can significantly improve the density and strength of the material, and reduce the cracks and pores in the material.
  • the styrene-acrylic emulsion improves the elastic modulus of the material and enhances the ability of the material to resist external negative factors.
  • the method not only solves the problem of borehole collapse caused by factors such as coal quality, mining depth and stress, but also improves gas extraction efficiency and reduces the probability of gas accidents.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Ceramic Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Structural Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Sealing Material Composition (AREA)
  • Working Measures On Existing Buildindgs (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
  • Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)

Abstract

一种松软煤层内全长筛管护孔并具有带压封孔的装置及方法，涉及瓦斯抽采技术领域，解决了钻孔（12）坍塌导致堵塞的问题。该装置包括注浆系统、抽采系统和固孔系统，注浆系统通过注浆压力泵（3）将带压密封材料注入钻孔（12），提高钻孔（12）的密封效果；抽采系统的抽采管（1）在金属挡板（7）和固孔筛管（6）上的通气孔（11）中间抽采瓦斯，通气孔（11）增强了气体的流通性；固孔系统在钻孔（12）内定位并通过金属挡板（7）固定，固孔筛管（6）之间通过卡口（9）和卡扣（10）连接固定；将该装置安装固定在瓦斯抽采钻孔内，封孔后抽采管连接抽采泵，进行瓦斯抽采。该瓦斯抽采装置及施工方法能够防止煤质、开采深度及高应力引起的钻孔（12）坍塌，还可以提升瓦斯抽采效率，保证瓦斯抽采过程的安全性。

Description

松软煤层内全长筛管护孔并具有带压封孔的装置及方法 技术领域
本发明涉及瓦斯抽采技术领域，尤其是一种松软煤层内全长筛管护孔并具有带压封孔的装置及方法。
 背景技术
在煤矿开采中，由于煤层赋存条件复杂多变，煤炭灾害频繁，瓦斯事故严重。煤层气是煤的伴生矿产资源，属非常规天然气，更是洁净、优质能源和化工原料，合理的利用矿井瓦斯，对降低矿井瓦斯事故，保护环境有着重要的意义。瓦斯抽采是解决瓦斯突出简单高效的方法，其中钻孔抽采应用最为广泛。但由于部分煤矿突出煤层和构造煤较软，开采深度大，高应力释放、转移及强载荷作用引起煤岩体破碎，以及大范围开采对煤岩体形成反复扰动，使煤岩体经历多次变形和破坏，在掘进巷道围岩应力场、瓦斯压力和煤体原生裂隙的影响下，钻孔的孔壁结构受到剪切破坏和张性破坏失稳，瓦斯抽放钻孔易塌孔，尤其是在工作面前方、巷道两帮应力集中段和局部构造应力集中段钻孔易在短时间垮塌堵死，导致钻孔瓦斯抽采钻孔的有效抽放时间大大减少，严重影响钻孔瓦斯抽采效率，为此需要对现有的瓦斯抽采装置及抽采方法做进一步的改进。
 技术解决方案
为了防止煤质松软、开采深度及高应力引起的钻孔坍塌，提升瓦斯抽采效率，保证瓦斯抽采的安全性，本发明提供了一种松软煤层内全长筛管护孔并具有带压封孔的装置及方法，具体技术方案如下。
一种松软煤层内全长筛管护孔并具有带压封孔的装置，包括抽采管、密封堵头、注浆压力泵、注浆管和出浆管，以及多个固孔筛管和多个金属挡板；所述固孔筛管通过金属挡板与瓦斯抽采钻孔的孔壁固定，多个固孔筛管依次首尾连接固定；所述密封堵头设置在瓦斯抽采钻孔的孔口段，两个密封堵头之间形成密封空间；所述注浆压力泵和注浆管相连，注浆管伸入密封空间内，出浆管和密封空间相通；所述抽采管穿过密封空间以及固孔筛管和金属挡板。
优选的是，固孔筛管的一端设置有卡口，另一端设置有卡扣；所述卡口与卡扣相互配合。
优选的是，金属挡板和固孔筛管上均匀的布置有多个通气孔；金属挡板的中央和密封堵头的中央均设置有抽采口，抽采管的管径等于抽采口的孔径。
优选的是，固孔筛管的两端设置有密封圈。
优选的是，密封空间内充填有带压密封材料，带压密封材料的组成为：硅酸盐水泥，纳米二氧化硅，硅酸钠，苯丙乳液和水。
一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，利用上述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，步骤包括：
A.连接固定抽采管和金属挡板，置于瓦斯抽采钻孔内；
B.将固孔筛管沿抽采管放入瓦斯抽采钻孔，金属挡板与固孔筛管配合固定；
C.依次连接金属挡板和固孔筛管；
D.固孔筛管安装完成后，在瓦斯抽采钻孔的孔口段内侧接入密封堵头，密封堵头和金属挡板贴紧；
E.在瓦斯抽采钻孔的孔口位置设置密封堵头，两个密封堵头之间形成密封空间；
F.连接注浆管和注浆压力泵，注浆压力泵通过注浆管将带压密封材料注入密封空间内；当出浆管出浆后停止注浆；
G.完成封孔，连接抽采管和瓦斯抽采系统，进行瓦斯抽采作业。
还优选的是，注浆管的管口伸入密封空间内侧，出浆管的管口伸至密封空间的外侧。
进一步优选的是，带压密封材料中水和硅酸盐水泥的质量比为0.4，纳米二氧化硅的添加量是硅酸盐水泥质量的4%，硅酸钠的添加量是硅酸盐水泥质量的0.5%，苯丙乳液的添加量是硅酸盐水泥质量的2%。
进一步优选的是，带压密封材料在制作时，先将纳米二氧化硅、硅酸钠、苯丙乳液与水混合，搅拌3分钟后加入硅酸盐水泥，继续搅拌直到材料混合均匀。
 有益效果
本发明提供一种松软煤层内全长筛管护孔并具有带压封孔的装置及方法有益效果是，该装置通过固孔筛管和金属挡板支撑钻孔内的空间，从而保证抽采管内气体的流动性，利用密封堵头在钻孔孔口段形成密封空间，充入带压密封材料从而提高钻孔的密封效果；利用该装置完成瓦斯抽采钻孔布置的方法具有，施工方便，护孔效果好，抽采效率高等优点。
 附图说明
图1是松软煤层内全长筛管护孔并具有带压封孔的装置结构示意图；
图2是固孔筛管结构示意图；
图3是金属挡板的结构示意图；
图中：1-抽采管，2-密封堵头，3-注浆压力泵，4-注浆管，5-出浆管，6-固孔筛管，7-金属挡板，8-密封圈，9-卡口，10-卡扣，11-通气孔，12-瓦斯抽采钻孔，13-密封空间；14-抽采口。
 本发明的实施方式
结合图1至图3所示，对本发明提供的一种松软煤层内全长筛管护孔并具有带压封孔的装置及方法具体实施方式进行说明。
一种松软煤层内全长筛管护孔并具有带压封孔的装置，该装置包括注浆系统、抽采系统和固孔系统，注浆系统通过压力泵将带压密封材料注入钻孔，提高钻孔的密封效果；抽采系统的抽采管在金属挡板和固孔筛管上的通气孔中间抽采瓦斯，增强了气体的流通性；固孔系统在钻孔内定位并通过金属挡板固定，固孔筛管之间通过卡口和卡扣连接固定；将该装置安装固定在瓦斯抽采钻孔内，封孔后抽采管连接抽采泵，进行瓦斯抽采。
其结构具体包括抽采管1、密封堵头2、注浆压力泵3、注浆管4和出浆管5，以及多个固孔筛管6和多个金属挡板7。其中注浆压力泵3布置在瓦斯抽采钻孔12的孔外，密封堵头2与注浆管4和出浆管5配合注浆封堵钻孔，抽采管1通过固孔筛管6和金属挡板7固定在瓦斯抽采钻孔内进行瓦斯抽采。
固孔筛管6通过金属挡板与瓦斯抽采钻孔12的孔壁固定，多个固孔筛管6依次首尾连接固定，固孔筛管6和瓦斯抽采钻孔12的孔径相近，并且略小于瓦斯抽采钻孔的孔径；金属挡板7设置在多个固孔筛管的连接处和端部。密封堵头2设置在瓦斯抽采钻孔的孔口段，两个密封堵头2之间形成密封空间13，密封空间3内充填带压密封材料，完成封孔。注浆压力泵3和注浆管相连，注浆管4伸入密封空间内，出浆管5和密封空间相通；通过注浆管4向密封空间内注入带压密封材料，出浆管5用于判断带压密封材料是否充满密封空间。抽采管1穿过密封空间以及固孔筛管和金属挡板，抽采管1可以沿注浆钻孔的轴线位置固定，从而更加方便瓦斯的抽采。
固孔筛管6的一端设置有卡口，另一端设置有卡扣，卡口与卡扣相互配合，从而方便固孔筛管的连接。金属挡板7和固孔筛管6上均匀的布置有多个通气孔11，方便气体流通，从而提升瓦斯抽采效率，金属挡板7的中央和密封堵头的中央均设置有抽采口14，抽采管1的管径等于抽采口14的孔径，从而方便固定抽采管。固孔筛管6的两端设置有橡胶密封圈，从而保证连接位置的密封性能。
其中密封空间13内充填有带压密封材料，带压密封材料的组成为：硅酸盐水泥，纳米二氧化硅，硅酸钠，苯丙乳液和水。密封材料应具有良好的流动性、致密性、粘结性以及力学强度，以便于在抽采过程中堵塞钻孔裂隙，消除或者减弱来自钻孔周围的应力，避免自身发生变形，产生破碎。
一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，利用上述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，步骤包括：
A.连接固定抽采管和金属挡板，置于瓦斯抽采钻孔内。其中抽采管的长度根据瓦斯抽采钻孔的长度确定，瓦斯抽采管的管径一般小于瓦斯抽采钻孔的孔径。
B.将固孔筛管沿抽采管放入瓦斯抽采钻孔，金属挡板与固孔筛管配合固定。固孔筛管的长度也根据瓦斯抽采钻孔的长度确定，一般每个固定孔筛管长度为1-3m，固孔筛管上均匀布置的通气孔，能够增强气体在瓦斯抽采钻孔内的流通。
C.依次连接金属挡板和固孔筛管，直至布置全部的固孔筛管，每个固孔筛管之间都通过金属挡板连接固定。
D.固孔筛管安装完成后，在瓦斯抽采钻孔的孔口段内侧接入密封堵头，密封堵头和金属挡板贴紧。其中先安装的密封堵头和钻孔最外侧的金属挡板贴紧，从而保证钻孔内结构的稳定性，钻孔的孔口位置为外侧方向，由孔口向孔底的位置为钻孔的内侧方向。
E.在瓦斯抽采钻孔的孔口位置设置密封堵头，两个密封堵头之间形成密封空间，通过设置两个密封堵头限制带压密封材料的流动，形成瓦斯抽采钻孔的封孔结构。其中注浆管的管口伸入密封空间内侧，从而方便浆液优选到达钻孔内侧，出浆管的管口伸至密封空间的外侧，保证及时判断是否注满。
F.连接注浆管和注浆压力泵，注浆压力泵通过注浆管将带压密封材料注入密封空间内；当出浆管出浆后停止注浆。其中带压密封材料中水和硅酸盐水泥的质量比为0.4，纳米二氧化硅的添加量是硅酸盐水泥质量的4%，硅酸钠的添加量是硅酸盐水泥质量的0.5%，苯丙乳液的添加量是硅酸盐水泥质量的2%。带压密封材料在制作时，先将纳米二氧化硅、硅酸钠、苯丙乳液与水混合，搅拌3分钟后加入硅酸盐水泥，继续搅拌直到材料混合均匀。带压密封材料在保留水泥基材料抗压、抗剪、强度大等优点的基础上，解决其失水收缩、裂隙丰富、密封效果差的问题。苯丙乳液、二氧化硅、硅酸钠协同作用能显著提高材料致密性与强度，减少材料中的裂隙与孔隙，苯丙乳液提高了材料弹性模量，增强了材料抵抗外界负面因素的能力。
G.完成封孔，连接抽采管和瓦斯抽采系统，进行瓦斯抽采作业。
该方法不仅解决了因煤质、开采深度以及应力作用等因素影响造成钻孔塌陷问题，还提高了瓦斯抽采效率，降低了瓦斯事故发生概率。
当然，上述说明并非是对本发明的限制，本发明也并不仅限于上述举例，本技术领域的技术人员在本发明的实质范围内所做出的变化、改型、添加或替换，也应属于本发明的保护范围。

Claims (9)

  1. 一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，包括抽采管、密封堵头、注浆压力泵、注浆管和出浆管，以及多个固孔筛管和多个金属挡板；所述固孔筛管通过金属挡板与瓦斯抽采钻孔的孔壁固定，多个固孔筛管依次首尾连接固定；所述密封堵头设置在瓦斯抽采钻孔的孔口段，两个密封堵头之间形成密封空间；所述注浆压力泵和注浆管相连，注浆管伸入密封空间内，出浆管和密封空间相通；所述抽采管穿过密封空间以及固孔筛管和金属挡板。
  2. 根据权利要求1所述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，所述固孔筛管的一端设置有卡口，另一端设置有卡扣；所述卡口与卡扣相互配合。
  3. 根据权利要求1所述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，所述金属挡板和固孔筛管上均匀的布置有多个通气孔；金属挡板的中央和密封堵头的中央均设置有抽采口，抽采管的管径等于抽采口的孔径。
  4. 根据权利要求1所述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，所述固孔筛管的两端设置有密封圈。
  5. 根据权利要求1所述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，所述密封空间内充填有带压密封材料，带压密封材料的组成为：硅酸盐水泥，纳米二氧化硅，硅酸钠，苯丙乳液和水。
  6. 一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，利用权利要求1至5任一项所述的一种松软煤层内全长筛管护孔并具有带压封孔的装置，其特征在于，步骤包括：
    A.连接固定抽采管和金属挡板，置于瓦斯抽采钻孔内；
    B.将固孔筛管沿抽采管放入瓦斯抽采钻孔，金属挡板与固孔筛管配合固定；
    C.依次连接金属挡板和固孔筛管；
    D.固孔筛管安装完成后，在瓦斯抽采钻孔的孔口段内侧接入密封堵头，密封堵头和金属挡板贴紧；
    E.在瓦斯抽采钻孔的孔口位置设置密封堵头，两个密封堵头之间形成密封空间；
    F.连接注浆管和注浆压力泵，注浆压力泵通过注浆管将带压密封材料注入密封空间内；当出浆管出浆后停止注浆；
    G.完成封孔，连接抽采管和瓦斯抽采系统，进行瓦斯抽采作业。
  7. 根据权利要求6所述的一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，其特征在于，所述注浆管的管口伸入密封空间内侧，出浆管的管口伸至密封空间的外侧。
  8. 根据权利要求6所述的一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，其特征在于，所述带压密封材料中水和硅酸盐水泥的质量比为0.4，纳米二氧化硅的添加量是硅酸盐水泥质量的4%，硅酸钠的添加量是硅酸盐水泥质量的0.5%，苯丙乳液的添加量是硅酸盐水泥质量的2%。
  9. 根据权利要求8所述的一种松软煤层内全长筛管护孔并具有带压封孔的瓦斯抽采方法，其特征在于，所述带压密封材料在制作时，先将纳米二氧化硅、硅酸钠、苯丙乳液与水混合，搅拌3分钟后加入硅酸盐水泥，继续搅拌直到材料混合均匀。
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