RU2604577C2 - Mine ventilation air heating method and device for its implementation - Google Patents

Abstract

FIELD: heating systems.

SUBSTANCE: group of inventions relates to heating systems, namely, to mine ventilation air heating method and device for its implementation. Method includes atmospheric air heating with flue gases, coming from fuel combustion chamber, its supply to mine through ventilation system. In ventilation air flow, directly into mine main ventilation fan suction channel, hot air addition is gradually supplying. In combustion chamber secondary blowing is used. Secondary air is heated in combustion chamber side walls convective jacket. In outlet gas flue cold air blowing is used, which is directed upwards at angle of not less than 45°. Fuel combustion chamber is equipped with secondary blowing fans located from inside and made in side walls by inclined slot nozzles. Fuel combustion chamber side walls outer surface is equipped with convective jacket. In fuel combustion chamber ceiling part gas burners are located. Improves mine air heating, while preventing flue gases ingress into ventilation flow supplied to mine.

EFFECT: enables increased air heating plant efficiency due to complete fuel combustion, reduced metal consumption of air duct.

4 cl, 3 dwg

Description

The invention relates to heating systems for various objects and is intended primarily for use when heating the air supplied to the mine.

There is a known method of regulating heat transfer in a ventilation system and a device for implementing this method (RF patent No. 2277205, IPC F24F 3/147), according to which air is periodically supplied by fans from the room to the street and from the street to the room through a heat storage nozzle with a layer of sorbent from the side ventilation facility.

The disadvantage of this method and device is the lack of functional reliability and the inability to use in mines and tunnels due to the fragility of the heat storage layer and sorbent and the inability to neutralize harmful products.

There is also a known method and device for heating air using an electric heating element and a layer-by-layer reciprocal air supply to it (RF patent No. 2280821, F24H 3/04).

Their disadvantage is the inability to neutralize harmful products of functioning and low efficiency.

The closest in technical essence to the claimed is a method of heating the air supplied to the mine, implemented in the device according to patent No. 2189533, F24D 15/00, adopted as a prototype, which provides for heating, transportation of hot air and its supply to the mine through the ventilation system at using a device for heating mine ventilation air.

The closest in technical essence to the claimed is a device for heating mine ventilation air according to patent No. 2189533, F24D 15/00, containing a fuel combustion chamber with side, front and fender walls and a ceiling part, an air heater, a hot air distribution device, a smoke exhauster and pipelines.

Their common drawbacks are lack of efficiency, the difficulty of creating an isothermal regime throughout the entire volume of the combustion chamber, as a result of which the fuel combustion process is not intensive enough, it works only on solid fuel, and low efficiency of the air heater.

The tasks to be solved by the claimed method and device are heating mine ventilation air by increasing the intensification of the fuel combustion process, improving heating of mine air due to the dosed supply of hot air additive in the mine ventilation stream, increasing the efficiency of an air heating installation due to complete combustion of fuel, elimination of flue gas entering the ventilation stream supplied to the mine, use of solid and gaseous fuels for burning, reducing e metal duct due to the high temperature of the additive of hot air.

The technical result of the claimed invention is expressed in the direct heating of the hot air additive supplied to the mine with flue gases while eliminating the ingress of flue gases into the ventilation stream supplied to the mine, improving the heating of mine air by dosing the hot air additive directly into the mine ventilation stream, heating the mine ventilation air by increasing the intensification of the fuel combustion process, increasing the efficiency of the air heater due to the full th combustion of fuel, use for burning solid and gaseous fuels, reducing the metal consumption of the duct.

The specified technical result is achieved by the fact that in the method of heating mine ventilation air, including heating the atmospheric air with flue gases coming from the fuel combustion chamber through the exhaust gas duct and the fuel combustion chamber, supplying it to the shaft through the ventilation system, according to the invention, the hot air additive is fed into the stream ventilation air is dosed, directly into the suction channel of the main ventilation shaft fan, secondary blasting is used in the combustion chamber, secondary Heated air is heated in the convective jacket of the side walls of the combustion chamber, and cold air is used in the outlet duct, which is directed upward at an angle of at least 45 ° to control the temperature of the flue gases.

The specified technical result is also achieved by the fact that in the combustion chamber of the fuel use combined combustion of fuel.

The specified technical result is also achieved by the fact that in the air heating installation of mine ventilation air containing a fuel combustion chamber with side, front and fender walls and a ceiling part, an air heater, a hot air distribution device, a smoke exhauster and pipelines, according to the invention, the fuel combustion chamber is provided located outside secondary blast fans and inclined slotted nozzles made in the side walls, which are located at a height of 0.8- 1 m from the surface of the furnace grate, so that the axis of the secondary air flow from each slot nozzle, except for the shut-off nozzles, is directed to the center of the fender and front walls of the fuel combustion chamber, and the outer surface of the side walls of the fuel combustion chamber is equipped with a convective jacket, which at the same time it is heat-insulated, in addition, a kind of emergency and working gates are installed in the pipeline, while the open position of the working gate corresponds to the closed position of the working gates o-emergency gate and vice versa.

The indicated technical result is also achieved by the fact that gas burners are located in the ceiling part of the fuel combustion chamber.

The invention is illustrated by drawings, where figure 1 shows a General view of the installation for heating mine air; figure 2 - chamber fuel combustion section aa in figure 1; figure 3 - section bb in figure 2.

A device for heating mine air comprises a combustion chamber 1 (hereinafter referred to as a combustion chamber) connected by means of gas ducts 2 to a smoke exhauster 3. Between the combustion chamber 1 and a smoke exhauster 3, an air heater 4 is installed, consisting of two stages 5 and 6 along the flue gas with the opposite direction and the gas hog 7, connecting the first 5 and second 6 stage, which acts as an inertial dust collector. The mine air heating device has a hot air fan 8 for supplying additive air from the environment to the air heater 4, from which the heated air through the duct 9 is supplied directly to the suction channel 10 of the main ventilation fan (VGP) 11, which supplies air to the mine.

The combustion chamber 1 contains a layer firebox 12 with a furnace web 13, lateral 14, frontal 15, baffle wall 16 and ceiling part 17 made of refractory material. In the side walls 14 of the combustion chamber 1 inclined slotted nozzles 18 are made so as to create a circular (cyclone) movement of the dusty air mixture inside the combustion chamber. The axis of the secondary air flow from each slot nozzle 18, except for the shut-off nozzles 19, is directed to the center of the baffle plate 16 and the front 15 of the walls of the combustion chamber, that is, the inclined slot nozzles 18 located in one side wall are inclined towards the front wall and located in the other side wall - towards the baffle wall. This direction of the inclined slotted nozzles 18 allows you to swirl the flow of dusty air mixture inside the combustion chamber, and, therefore, equalize the temperature inside the combustion chamber throughout its volume, increase the time spent by small particles of fuel in the furnace volume, for their complete burnout and reduce chemical underburning. The shut-off nozzles 19 provide additional circular rotation of the dust-air mixture flow and prevent the rapid discharge of dust particles from the combustion chamber 20 into the afterburner 21.

The outer surface of the side walls 14 of the combustion chamber 1 is equipped with a convective jacket 22, which is also heat insulation, which is made in the form of a metal shield installed from the upper edge of the side wall 14 of the combustion chamber of fuel 1 at a distance of 50-70 mm from its outer surface to the level of the furnace web and hermetically sealed at the ends. Convective shirt 22 can reduce heat loss to the environment. The fuel combustion chamber 1 is equipped with external secondary blast fans 23. The secondary blast fan 23 is supplied with air under pressure into a convective jacket 22, from which, through the inclined slotted nozzles 18 located in the side walls 14 of the combustion chamber 1, heated secondary air at a speed of 40 -50 m / s is fed into the combustion chamber 1. This speed allows you to swirl the flow of dusty air mixture inside the combustion chamber.

If the reserves and concentration of mine methane in the mine degassing system allow for the continued use of methane, then combined combustion of fuel - gas and solid fuel - is used. To supply gas to the fuel combustion chamber, gas burners 24 are installed in its ceiling part.

The inventive device operates as follows.

Solid or combined fuel is fed into combustion chamber 1 and ignited. After the fuel has been ignited, that is, the temperature in the combustion chamber has reached 400-500 degrees, the secondary blast fans 23 are turned on (initially with a small capacity) 23. With a further increase in the temperature of the flue gases in the combustion chamber 1, the secondary blast flow is increased until the combustion process exits in the operating mode, in which the amount and temperature of flue gases and hot air reach the calculated values. Hot flue gases, which are formed during the combustion of fuel in the combustion chamber, are exhausted from the combustion chamber 1 through the air ducts 2 through the exhaust fan 4 through the air heater 4 and emitted through the chimney into the atmosphere. The hot air fan 8 supplies additive air from the environment to the air heater 4, where it is heated to a predetermined temperature (for example, up to 300 °). While the air is being heated to a predetermined temperature, the emergency-fire gate 25 is opened. (The emergency-fire gate 25 is also opened during an emergency on the main ventilation fan 11). As soon as the air reaches a predetermined temperature, the emergency-fire gate 25 is closed and the working gate 26 is opened. The emergency-fire 25 and the working gate 26 are controlled, for example, by one common drive, operating so that the open position of the working gate 26 corresponds to the “closed” position »Emergency-shutter gate 25 and vice versa. Additive air heated to a predetermined temperature is fed directly to the suction channel 10 of the main ventilation shaft fan (AHF) 11, which ensures high-grade heat exchange th additives and main air flow in the flow part of AIV and eliminates movement of the main flow of hot and cold layers in the discharge channel mine ventilation.

In the exhaust duct 27 of the combustion chamber 1, to regulate the temperature of the exhaust gases, cold air blowing is used using an axial fan 28. In this case, the flow of charge air is carried out upward at an angle of at least 45 ° in order to prevent this air from entering the afterburner 21.

The inventive method is as follows. The fuel is burned in the fuel combustion chamber 1. To intensify the process of fuel combustion in the combustion chamber, secondary blasting is used, which ensures isothermal operation throughout its volume. Secondary air is additionally heated in a convective jacket 22 of the side walls 14 of the combustion chamber to a temperature of 250-300 °. In this case, the convective shirt 22 of the combustion chamber 1 simultaneously performs the role of thermal insulation. The combustion products of the fuel (flue gas) through the duct 2 is fed into the heating circuit of the heat exchanger 4. And in the heated circuit of the heat exchanger 4 serves atmospheric air. The resulting hot atmospheric air is dosed (that is, depending on the required heat output, the amount of additive that is necessary to create the desired temperature in the mine is supplied) through the duct 9 as a hot additive directly into the suction channel 10 of the mine fan of the main ventilation 11 of the underground mine workings .

An advantage of the proposed device and method is the possibility of a dosed supply of hot air additives directly into the mine ventilation flow without the installation of heat exchangers (heaters, heat exchangers) directly on the mine air intake.

The inventive method and device allow:

- to improve the heating of mine air due to the dosed additive of hot air into the mine ventilation flow and supplying it directly to the suction channel of the main ventilation mine fan;

- to intensify the process of burning fuel, through the use of secondary blasting;

- increase the efficiency of the air heater due to more complete combustion of the fuel, which is achieved by the organization of the secondary blast and feeding it through inclined slotted nozzles into the combustion chamber;

- use both solid and combined (gas plus solid fuel) fuel for combustion, due to gas burners installed in the ceiling of the combustion chamber, and, therefore, utilize methane and save solid fuel;

- reduce heat loss to the environment due to the fact that the combustion chamber is equipped with a convective jacket.

Claims (4)

1. A method of heating mine ventilation air, comprising heating atmospheric air with flue gases coming from a fuel combustion chamber through an exhaust gas duct and a fuel combustion chamber, supplying it to a mine through a ventilation system, characterized in that it enters the ventilation air stream directly into the mine’s suction channel main ventilation fan, a dosed additive of hot air is dosed, secondary blasting is used in the combustion chamber, secondary air is heated in a convective jacket on the side x the walls of the combustion chamber, and in the exhaust duct use blowing of cold air, which is directed upward at an angle of at least 45 °. 2. The method according to claim 1, characterized in that the combined combustion of fuel is used in the fuel combustion chamber. 3. A device for heating mine ventilation air, comprising a fuel combustion chamber with side, front and baffle walls and a ceiling part, an air heater, a hot air distribution device, a hot air fan, a smoke exhaust, gas ducts and an air duct, characterized in that the fuel combustion chamber is provided with disposed outside by secondary blast fans and inclined slotted nozzles made in the side walls, which are located at a height of 0.8-1 m from the surface of the furnace floor so that the axis of the secondary air flow coming from each slot nozzle, except the shut-off nozzles, is directed to the center of the fender and front walls of the fuel combustion chamber, and the outer surface of the side walls of the fuel combustion chamber is equipped with a convective jacket, which is also a heat insulation made in the form of a shield installed from the upper edge of the side wall of the combustion chamber at a distance of 50-70 mm from its outer surface to the level of the furnace web and hermetically closed at the ends, in addition, in the outlet g a fan is located in the inlet, and a fire-emergency and working gates are installed in the duct, while the “open” position of the working gate corresponds to the “closed” position of the fire-emergency gates and vice versa. 4. The device according to claim 3, characterized in that the fuel combustion chamber is equipped with gas burners, which are located in its ceiling part.

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