WO2013178012A1

WO2013178012A1 - Method for fluid carriage in deep-seam coal hydraulic mining

Info

Publication number: WO2013178012A1
Application number: PCT/CN2013/075447
Authority: WO
Inventors: 秦勇; 郭竹楠; 李建萍
Original assignee: Qin Yong; Guo Zhunan; Li Jianping
Priority date: 2012-05-29
Filing date: 2013-05-10
Publication date: 2013-12-05
Also published as: CN102777151A; EP2857635A1; US20150337600A1; CN103437764A

Abstract

The present invention relates to a method for fluid carriage in deep-seam coal hydraulic mining, aimed at the mining of coal seams buried underground at depths of 500 metres to below several thousands of metres. By means of methods such as well drilling and tubular columns, hydraulic power is conveyed to the coal seam excavation using tubular columns, to erode and cut coal buried underground, and by circulating fluid at a certain flow rate, cut coal is carried to the surface, achieving unmanned excavation in the shaft. The present method is an integrated coal exploitation technique achieving synchronous mining of coal field gas and solids, and is suitable for coal seams where conventional methods are unable to mine or mining is not economically viable, while also being suitable for establishing gasification channels for underground coal gasification.

Description

Method for carrying deep coal hydraulic enthalpy mining fluid carrier

Technical field

The invention relates to a new process for carrying deep coal hydraulic exploitation fluids, mainly for the exploitation of coal seams buried deep below 500 meters to several kilometers below ground.

Background technique

Through the drilling, pipe column and other processes, the coal buried deep underground is washed and cut, and the cut coal is taken out of the ground by the circulation of the fluid. The use of the pipe string to transfer hydraulic power to the coal seam and use the fluid to transport coal to the ground for unmanned underground mining. Book

It is a coal development technology that realizes the simultaneous extraction of gas and solids in coal fields. It is especially suitable for coal seams that cannot be mined or uneconomically produced by conventional methods, and is also suitable for the establishment of gasification passages for underground coal gasification.

Summary of the invention

In order to overcome the deficiencies of the prior art, the present invention provides a new process for deep coal hydraulic production fluid carrying, especially a hydraulic mining fluid carrying method for a coal seam below a depth of underground kilometers. The method includes:

1. According to the resources of coal resource exploration and the actual situation of geological structure, prepare the overall development plan in the resource area;

2. According to the overall plan, implement single or multiple wells and develop at the same level;

3. In the development of multiple sets of coal seams, it should be based on the development principles from deep to shallow;

4. The pressure coefficient of the coal seam should be greater than 0.9 to ensure the economic implementation of the development plan;

5. Establish drilling wells using drilling technology. Specific: Using drilling technology, drilling to the top of the deepest coal seam, casing cementing, drilling cement plugs, and opening the coal seam;

6. Using a directional drilling process, using a specific hydraulic cutting bit and a specific double column, prepare a a constant performance fluid produced by a surface mud pump;

1) directional drilling technology, using underground TV, locator, and direction meter to ensure the quality of the tunneling;

2) For specific hydraulic cutting bits, hydraulic cutting bits with different parameters should be customized according to the thickness of the coal seam and the inclination of the coal seam. Main parameters: speed, water eye diameter, water eye jet angle;

3) For specific double-column columns, depending on the capacity, use columns of different diameters;

4) Fluid performance should be based on coal seam pressure coefficient and density. Main performance indicators: density, viscosity, shear force; fluid formulation (referred to as coal lye) mainly water, alumina, caustic soda (sodium hydroxide), coal powder and vermiculite Powder

5) The parameters of the mud pump are mainly pressure (generally high pressure, greater than 10 MPa), displacement;

7. Carry a mixture of coal and gas (CH4) to the ground through a fluid at a certain flow rate into the ground treatment system.

1) Mixture of mud, coal and gas, first enter the three-phase separator, and separate the mud, coal and gas simultaneously;

2) Gas (CH4) enters the gas treatment station and is pressurized to the user;

3) The coal blocks enter the coal washing workshop, and the processed fine coal is transferred to the fine coal warehouse for sale. The ash powder and vermiculite in the coal washing workshop enter the vermiculite grinding room and are processed to the powder below 200 mesh for slurry mixing; the waste water in the coal washing room is transferred to the mud mixing room for formulating the mud;

4) The mud flows from the three-phase separator into the sedimentation tank, and the fine coal and fine sand are precipitated. The sediment is transferred to the coal washing room and the mud is recycled to the circulating pool. According to the development plan, multi-well and multi-layer well nets will be set up to implement groundwater power coal mining operations. For mining areas with multiple coal seams, it is best to first mine the bottom coal seam and then, in turn, to the upper layer for mining. The specific advantages are as follows:

1. Realize synchronous mining of gas and solid in coal fields, with high resource utilization rate; coal recovery rate can reach above 8C; gas is fully recycled;

2. Nobody in the underground, hydraulic operation, to avoid gas explosions such as conventional coal mining, landslides and other safety accidents.

3. Environmental protection has more advantages than conventional coal mining, does not damage the surrounding environment, production area /J pollution-free water discharge, no waste, vermiculite, no dust, gas is fully recycled.

4. It can make full use of the stock resources of various places, avoid long-distance transportation of coal and reduce energy consumption.

5. Less construction investment, short cycle and high production efficiency.

6. Vigorously explore and develop deep resources based on coking coal, which can make up for the shortage of resources.

: fii is obvious.

DRAWINGS

Figure 1 is a cross-sectional view showing the process flow of the present invention;

Figure 2 is a plan view of the process flow of the present invention;

1 Transformer and power distribution 6 Natural gas processing station 11 Separated coal

2 7 users 12 coal washing plant

3 Mud circulation pool 8 Sedimentation tank 13 Clean coal pool

4 wellhead 9 sedimentation treatment device

5 three-phase separator 10 separated liquid phase detailed description

The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings.

Referring to Figure 1, the present invention utilizes drilling process technology, including power distribution (1), power distribution cabinet (2), mud circulation pump (3), well winch (4), derrick (5), drilled to the top of the deepest coal seam. , lower the casing (16) for cementing, then drill the cement plug and open the coal seam (17). The coal seam pressure coefficient is required to be greater than 0.9 to ensure the economic implementation of the development plan.

Referring to Figure 1, the present invention utilizes a directional drilling process to deliver a fluid of a certain performance (12) through a ground mud pump (3), using a specific double column, inner column (14), to transfer hydraulic power to the coal seam. Excavation, using a specific hydraulic cutting bit (13) to scouring and cutting coal buried in the ground. The fluid mixture at a certain flow rate is then used to transport the coal mixture to the surface and into the surface treatment system.

Referring to Figure 1, the parameters of the mud pump (3) in the present invention are mainly pressure and displacement, and the pressure requires high pressure, generally greater than 10 MPa.

Referring to Figure 1, the specific double-column, inner (14) and outer (15) tubes of the present invention are to be used with different diameters (14, 15) depending on the production capacity. The performance of the fluid (12) in the present invention is determined according to the pressure coefficient and density of the coal seam, and the main performance indexes are: density, viscosity, and shear force.

Referring to Figure 1, the specific hydraulic cutting bit (13) of the present invention is customized according to the thickness and inclination of the coal seam (17), and the hydraulic cutting bit (13) with different parameters is customized. Main parameters: rotational speed, water eye diameter, water jet angle.

Referring to Figure 1, the formulation of the fluid (12) in the present invention, abbreviated as coal lye, is mainly composed of water, alumina, caustic soda (sodium hydroxide), coal powder and vermiculite powder.

Referring to Figure 2, this figure is a process flow plan, including power distribution (1), pump (2), mud circulation pool (3), wellhead (4). In the present invention, the coal mixture first enters the three-phase separation system (5), and separates the mud (10), the coal (11), and the gas (7), respectively. Referring to Fig. 2, in the present invention, the gas CH4 enters the gas treatment station (6) and is pressurized to the user.

Referring to Figure 2, in the present invention, the coal block (11) enters the coal washing plant (12), and the processed clean coal to the fine coal store (13) is for sale.

Referring to Fig. 2, in the present invention, the slurry (10) is separated and flows into the sedimentation tank (8), and the fine coal and fine sand are precipitated by a sedimentation treatment device (9), and the sediment is transferred to a coal washing plant (12) for treatment, mud. Loop to the loop pool (3) for use.

Claims

claims

1. A new technology for deep coal hydraulic mining fluid transportation, which is characterized by:

(1) Coal development technology that integrates simultaneous mining of gas and solids in coal fields, especially suitable for coal seams that cannot be mined by conventional methods or are uneconomical to mine;

(2) At the same time, the establishment of gasification channels suitable for underground coal gasification;

(3) Utilize directional drilling technology, use specific hydraulic cutting drill bits and specific double-layer pipe strings, prepare fluids with certain properties, use the fluids as carriers, and use the flow rate of the fluids to bring the deep underground coal mixture out of the ground;

(4) Use a three-phase separator system to simultaneously separate the mud, coal, and gas in the mixture;

(5) Coal gas (CH4) enters the gas processing station and is pressurized before being sent to the user; the coal blocks enter the coal washing workshop, and the processed clean coal is transferred to the clean coal warehouse for later sales; the slurry is circulated to the circulation pool for recycling.

2. A new technology for deep coal hydraulic mining fluid transportation as claimed in claim 1, characterized by preparing an overall development plan for the resource area based on the amount of coal resource exploration and the actual situation of the geological structure. According to the overall plan, the simultaneous development of a single well or multiple wells in the same layer will be implemented.

3. A new technology for deep coal hydraulic mining fluid transportation as claimed in claim 1, characterized in that this new technology is also suitable for the establishment of gasification channels for underground coal gasification.

4. A new technology for deep coal hydraulic mining fluid transportation as described in claim 1 or 2, characterized in that in the development of multiple sets of coal seams, the development principle from deep to shallow should be followed. The pressure coefficient of the coal seam is required to be greater than 0.9 to ensure the economic implementation of the development plan.

5. A new technology for deep coal hydraulic mining fluid transportation as claimed in claim 1, characterized by using drilling technology to establish production wells. Using drilling technology, after drilling to the top of the deepest coal seam, the casing is cemented, and then the cement plug is drilled to open the coal seam.

6. A new process for deep coal hydraulic mining fluid transportation as claimed in claim 3 or 4, which utilizes a directional drilling process, uses a specific hydraulic cutting drill bit and a specific double-layer pipe string, and then prepares a certain The fluid is finally produced through surface mud pumps.

7. A new technology for deep coal hydraulic mining fluid transportation as claimed in claim 5, characterized by utilizing directional drilling technology and using underground televisions, locators, and direction meters to ensure the quality of excavation.

8. A new process for carrying fluid in deep coal hydraulic mining as claimed in claim 6, characterized in that a specific hydraulic cutting bit is customized with different parameters based on the thickness and inclination of the coal seam. The main parameters are: rotation speed , water eye diameter, water eye jet angle. As claimed in claim 6, a new technology for deep coal hydraulic mining fluid transportation is characterized in that specific double-layer pipe strings are used, and pipe strings of different diameters are used according to production capacity. The performance of the fluid must be formulated based on the coal seam pressure coefficient and density. The main performance indicators are: density, viscosity, and shear force. The fluid formula (coal lye for short) is mainly prepared from water, clay, caustic soda (sodium hydroxide), coal powder and gangue powder. The parameters of the mud pump are mainly pressure (usually high pressure) and displacement.

9. A new process for deep coal hydraulic mining fluid transportation as claimed in claim 1, characterized in that a mixture of coal and gas (CH4) is carried back to the surface by a fluid with a certain flow rate and enters the surface treatment system.

10. A new process for deep coal hydraulic mining and fluid transportation as claimed in claim 10, characterized in that the fluid mixture first enters the three-phase separation system, and the mud, coal, and gas are separated simultaneously. Coal gas (CH4) enters the gas processing station and is pressurized before being sent to the user; the coal blocks enter the coal washing workshop, and the processed clean coal is transferred to the clean coal warehouse for later sales. The ash powder and gangue from the coal washing workshop enter the gangue grinding room and are processed into materials below 200 mesh for mud preparation; the waste water from the coal washing room is transferred to the mud liquid preparation room for mud preparation. The mud flows from the three-phase separator into the sedimentation tank, where the pulverized coal and fine sand particles are precipitated. The sediment is transferred to the coal washing room for treatment, and the slurry is circulated to the circulation tank for use.