RU2311531C2 - Method for underground coal gasification - Google Patents

Abstract

FIELD: mining, particularly underground gasification of coal pillars left after deep coal seam development technology application.

SUBSTANCE: method involves sinking inclined mine roadways connected with ground surface by upper ends thereof and with each other by lower ends to create combustion face; using coal pillars left after deep coal seam development technology usage for underground gasification, wherein in accordance with said technology pillar separating two chambers is pierced with well having dimensions enough for combustion face forming and the well head is surely sealed. Gas blowing or discharge means is provided in insulation bridge. Coal pillars are combusted in turns.

EFFECT: decreased coal losses in pillars and possibility to use previously excavated chambers from ground surface.

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Description

The invention relates to the mining industry and can be used for underground gasification of the pillars of coal remaining after applying the technology of deep mining of coal seams.

At present, in coal mines of the Russian Federation, the technology of deep development of coal seams is beginning to be applied, which consists in drilling from the surface of the chambers and leaving pillars of coal [1]. However, coal losses in pillars reach 40%. It is possible to reduce these losses with the help of underground coal gasification.

There is a method of underground coal gasification, which includes opening a coal seam with boreholes, igniting coal and mining seams by supplying reagents and removing combustion products [2].

The disadvantages of this method are:

- difficulty in creating reaction channels;

- the difficulty of regulating combustion processes.

A known method of underground gasification, including the formation of two inclined workings in the reservoir, interconnected by a horizontal drift and with the surface of the earth by vertical wells [3] is a prototype.

The main disadvantage of this method is that to burn the next block of coal, it is necessary to conduct inclined workings again, to connect them with a fire drift, as well as to drill other wells from the surface.

The technical task was to reduce coal losses in pillars and the use of previously passed chambers from the surface.

The technical result obtained is a significant reduction in coal losses when using underground coal gasification.

The proposed method is characterized in that for underground gasification using coal pillars, remaining after applying the technology of deep mining of coal seams, for which, when coal is extracted using this technology, an interchamber pillar is drilled at the end of the chamber with a borehole sufficient for the subsequent organization of fire slaughter in it, and after works in the chamber of the mouth, it is reliably sealed, and in the insulating jumper provide a device for blasting or gas extraction, and the subsequent burning of the pillars of coal is carried out alternately.

Introduced into the claims, such an essential feature, as the fact that coal pillars are used for underground gasification, which remain after the exploitation of the field by the technology of deep mining of coal seams, ensures the completeness of coal extraction, significantly reduces coal losses in pillars.

An essential sign that at the end of the chamber an interchamber pillar is drilled with a borehole sufficient for the subsequent organization of fire face in it allows ignition and subsequent combustion of coal.

The next significant sign that the mouth of the chambers is reliably sealed, eliminates the communication of the chambers with the surface, prevents the entry of surface water into them.

An essential sign that devices for blasting or venting are provided in the isolation bridges makes it possible to reliably conduct underground gasification of coal.

An essential sign that the burning of the pillars of coal is carried out alternately allows gasification of all pillars during a one-time ignition of coal.

The method is illustrated by drawings, where Fig. 1 shows a plan of the location of mine workings after mining a section of a formation using deep mining technology, Fig. 2 is a section A-A in Fig. 1.

Symbols adopted in the drawings: 1 - coal seam; 2 - camera; 3 - coal pillar; 4 - well; 5 - insulating jumper; 6 - device for blasting (gas outlet).

The method is as follows.

When excavating the coal seam 1 using the technology of deep mining of coal seams, the chambers 2 are drilled leaving coal pillars between them 3. Drilling is carried out without the presence of people in the chambers 2. When the drilling organ of the unit finishes holding the chamber 2, a well 4 is drilled in the inter-chamber pillar 3 using drilling machine mounted on the drilling organ. Drilling wells 4 are also remotely. After the unit moves to a new place for drilling the next chamber 2, the mouth of the finished chamber 2 is sealed by installing an insulating jumper 5, in which the device for blasting 6 is installed. The same device is also used for gas extraction. After the excavation works are completed, in the block allocated for this purpose, underground gasification of the remaining coal pillars 3 is carried out, the coal reserves of which reach 40%. To do this, reagents are supplied to the borehole 4 of the initial chamber 2 and coal is ignited, creating a fire face. The blasting is carried out through the blasting device in the insulating jumper 5, the initial chamber 2, and the gas outlet is produced through the device 6 of the other jumper 5. In the process of burning the first pillar of coal 3 and creating high temperatures, the next pillar 3 lights up, and the gas outlet is moved to the subsequent jumper 5. Thus Thus, moving the blast and gas outlet, all pillars 3 of this block are burned out.

The advantages of this method:

- Excluded mining;

- Coal losses are reduced to a minimum.

Information sources

1. A.G. Netsvetaev, L.N. Repin, A.V. Sokolovsky, A.V. Yutkin The first Russian experience in the application of deep mining of coal seams: mass stability and coal loss in the bowels, M., “Coal”, No. 12, 2004, pp. 10-12.

2. RF patent No. 2186209, ЕВВ 43/295, 2002

3. V.Zh.Arens Physico-chemical geotechnology. - M .: Publishing house of the Moscow State Mining University, 2001. - S.370-371.

Claims (1)

A method of underground coal gasification, including inclined mine workings along a coal seam connected to the surface in the upper part and to each other in the lower part to create a fire face, characterized in that the coal pillars remaining after the deep seam mining technology are used for underground gasification, why, when coal is mined using this technology, at the end of the chamber, the entire interchamber is drilled with a borehole sufficient for the subsequent organization of fire slaughter in it, and after the work is completed in the chamber, ste it securely sealed, the insulating crosspiece provide a device for blowing or flue gas, and the subsequent burning of coal pillars are alternated.

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