CN1062330C - propelling air supply type coal underground gasification furnace - Google Patents

Abstract

The push-air supply type underground coal gasification furnace is particularly suitable for direct underground coal gasification. Inlet and outlet holes are constructed on the ground, and a certain number of auxiliary air supply holes are constructed between the inlet and outlet holes and connected to the air supply system. A push-type auxiliary air duct is arranged in the gasification channel, and several constant temperature fusible baffles are installed in the auxiliary air duct in sections, thereby increasing the diffusion coefficient of gas molecules in the gasification channel. When the gasification channel is blocked, the auxiliary air duct can directly deliver the gasification agent to the gasification working face; when the coal seam gasification height is relatively high, the auxiliary air supply holes will play a role, so that the underground coal gasification can proceed smoothly, and it has a very broad application prospect.

Description

Promoting air supply underground coal gasifier

The invention relates to a propulsion air supply underground coal gasification furnace, especially suitable for direct underground coal gasification.

Underground coal gasification furnace is composed of air intake hole, exhaust hole and gasification channel. The underground gasification furnace used in the past has only one fixed air supply point, that is, the bottom of the air intake hole. However, as the gasification working surface is far away from the air intake hole, it is difficult for the fixed-point air supply to send the gasification agent directly to the combustion working surface, thus destroying the temperature conditions required for the gasification reaction, resulting in a decrease in the calorific value of the gas . What's more, the consumption of gasification agent in the combustion face is very small, while a large amount of gasification agent (O ² ) forms a bypass flow and mixes with the gas on the exhaust side, resulting in secondary combustion, which greatly reduces the calorific value of the gas. In addition, fixed-point air supply makes it difficult to control the gasification speed, and when the coal seam falls in a large area, the gasification agent cannot reach the combustion face, resulting in the interruption of the gasification process.

The object of the present invention is to provide a push air supply underground coal gasifier capable of controlling the supply area of the gasification agent, so as to realize the stability and continuity of the gasification process.

The present invention promotes the air-supply type underground coal gasifier, selects a suitable coal seam in the mine, constructs the intake and exhaust holes on the ground, matches with the intake and exhaust facilities, excavates the coal lane underground, and connects the intake and exhaust holes to form a The gasification channel is provided with a propulsion auxiliary air channel in the middle of the gasification channel, and a constant temperature fusible partition is arranged in the auxiliary air channel to divide the auxiliary air channel into several sections; The air hole channel pipe is connected with the air intake hole, and there is a certain distance between the air intake hole and each auxiliary air supply hole. Road connected.

The air-supply type underground coal gasification furnace of the present invention, the gasification channel is located in the middle of the coal seam, and the section is the construction section of a general coal roadway. The length and support form depend on the occurrence conditions of the coal seam. The air duct is made of ordinary kiln bricks, with a rectangular or dome-shaped cross-section. The ratio of the cross-sectional area to the cross-sectional area of the gasification channel is 1:50 to 1:80. channel lengths are equal. The temperature-fixed fusible partitions arranged in the push-type auxiliary air duct shall be installed every 10D, where D is the equivalent diameter of the gasification channel. The diameter of the auxiliary air supply hole is smaller than the diameter of the intake and exhaust holes, and the sum of its cross-sectional area is equal to the section of the air intake hole. The auxiliary air supply hole drills along the coal seam to the top of the gasification channel, and the distance from the air intake hole and between them is 30D, D is the equivalent diameter of the gasification channel.

The air-supply type underground coal gasifier of the present invention is constructed with intake and exhaust holes on the ground, and a certain number of auxiliary air-supply holes are constructed between the intake and exhaust holes, and are connected with the air-supply system. The propulsive auxiliary air duct is arranged, and a constant temperature fusible partition is installed in the auxiliary air duct, so that the air flow is divided into several fine streams by the auxiliary air duct and blown vertically to the gasification working face, which improves the diffusion coefficient of gas molecules in the gasification channel. When the gasification channel is blocked, the auxiliary air duct can directly send the gasification agent to the working face of the gasification port to form a vertical upward seepage gasification; Underground coal gasification has been carried out smoothly, and it has achieved good results through field semi-industrial tests, and has a very wide application prospect.

Description of drawings:

Accompanying drawing is the structural diagram of the air-supply type underground coal gasifier of the present invention.

1-air intake hole, 2-air supply pipe, 3-auxiliary air supply hole, 4-propelled auxiliary air duct, 5-gasification channel, 6-gasification coal seam, 7-exhaust hole.

An embodiment of the present invention will be further described below in conjunction with accompanying drawing:

The present invention promotes the air-supply type coal underground gasifier, selects a suitable coal seam in the mine, constructs the inlet and outlet holes 1 and 7 from the ground, and constructs a certain number of auxiliary air supply holes between the inlet and outlet holes 1 and 7 3. Connect the air inlet 1 and the auxiliary air supply hole 3 with a pipe 2 of equivalent diameter, and connect with the air supply system. In the underground coal roadway excavation, the inlet and outlet holes 1 and 7 are connected to form a gasification channel 5, and the auxiliary air channel 4 of the advancing air supply type is arranged in the gasification channel 5, thus forming the advancing air supply type coal underground gasifier. The inlet and outlet holes 1 and 7 of the gasifier are constructed by ordinary drilling technology, and the whole drilling depth needs to be placed with a casing, and its diameter depends on the gas output. The inlet and outlet holes are generally located on the coal seam floor or on the inclined hole and drilled along the coal seam. When drilling along the coal seam, the sleeve pipe in the gasification coal seam 6 is a flower pipe, that is, several holes are drilled on the sleeve pipe. The diameter of the auxiliary air supply hole 3 is about a quarter of the diameter of the inlet and outlet holes 1 and 7, drilled along the coal seam to the top of the gasification channel 5, and the distance from the air inlet 1 and each other is 30D, D is the equivalent diameter of the gasification channel 5 . The gasification channel 5 is located in the middle of the coal seam, and the section is the general coal roadway construction section. The length and support form depend on the occurrence conditions of the coal seam. In the middle of the gasification channel 5, the auxiliary air duct 4 is arranged. Made of bricks, the cross-section is rectangular, the ratio of the cross-sectional area to the cross-section of the gasification channel is 1:60, there are flower walls on both sides, and there are certain pores on the covering surface, whose length is equal to the length of the gasification channel 5 . The bottom of the air intake hole 1 is connected with the auxiliary air duct 4 . In the propulsive auxiliary air duct 4, a constant temperature fusible partition is installed every 10D to divide the propulsion air duct 4 into several sections.

When the gasification furnace is ignited, the air is supplied from the air inlet 1, and part of the air flow directly enters the gasification channel 5 from the flower tube, and the main air flow will enter the auxiliary air channel 4. The pores on both sides and the top surface of the auxiliary channel 4 are divided into several thin streams and blown vertically to the gasification working face, which improves the diffusion coefficient of gas molecules in the gasification channel 5 . When the combustion working surface moves to the first partition, the first partition automatically melts, so that the air supply area reaches the second partition, and moves forward with the combustion working surface. When the coal seam in the combustion zone falls, the fire zone will be covered on the auxiliary air channel 4, and the air flow in the auxiliary air channel 4 will form a vertical upward seepage gasification to maintain the continuous gasification process. When the gasification channel 5 is blocked , the auxiliary air duct 4 can still directly send the gasification agent to the combustion zone; when the gasification coal seam 6 has a high combustion height, the auxiliary air supply hole 3 and the auxiliary air duct 4 are used in combination to form a propulsion air supply system.

Claims (4)

1. Promoting the air-supply underground coal gasifier, selecting a suitable coal seam in the mine, constructing air intake holes (1) and exhaust holes (7) on the ground, matching them with air intake and exhaust facilities, and digging coal lanes underground , exhaust holes (1), (7) are connected to form a gasification passage (5), which is characterized in that: a propulsion auxiliary air duct (4) is set in the middle of the gasification passage (5), and in the auxiliary air duct (4) A fixed temperature fusible partition is arranged to divide the auxiliary air duct into several sections; several auxiliary air supply holes (3) are arranged on the top of the gasification channel (5), and the auxiliary air supply holes (3) pass through the pipe (2) and The air intake hole (1) is connected, and there is a certain distance between the air intake hole (1) and each auxiliary air supply hole and between each other. The air intake and exhaust holes (1), (7) are in the coal seam The casing pipe is a flower pipe, and the bottom of the air inlet (1) is connected with the auxiliary air duct (4). 2. The propulsion air supply underground coal gasifier according to claim 1, characterized in that: the propulsion auxiliary channel (4) is made of ordinary kiln bricks, the cross-section is rectangular or dome-shaped, and the cross-sectional area is equal to the cross-sectional area of the gasification passage. The ratio is 1:50-1:80, the two sides are flower walls, and there are pores on the upper covering surface, the length of which is equal to the length of the gasification channel (5). 3. According to claim 1 or 2, the propulsion air supply underground coal gasifier is characterized in that: the constant temperature fusible partitions arranged in the propulsion auxiliary air duct (4) are arranged every 10D, and the D is the equivalent diameter of the gasification channel (5). 4. The propulsion air supply underground coal gasifier according to claim 1 or 2, characterized in that: the diameter of the auxiliary air supply hole (3) is smaller than the diameter of the inlet and exhaust holes (1), (7), and its cross-sectional area The sum is equal to the sectional area of the air intake hole, and the auxiliary air supply hole (3) is drilled along the coal seam to the top of the gasification channel, and the distance from the air intake hole (1) and between them is 30D, and the D is the gasification Equivalent diameter of channel (5).