SK277956B6 - Heating method of fluid layer by given of fluid focus into working and fluid combusting device for realization of this method - Google Patents

Abstract

Heating method of fluid layer (6) by given of fluid focus (1) into working and device for realization of this method, by which the hot gases from approaching torch (2) are exhausted through fluid layer (6) in opposite direction as the direction of flowing of combusting air leaded by working of fluid combustion device (11) in to fluid layer (6) and after its transition through fluid layer (6) are an temperature around 250 degrees of Celsius are by mixing with air cooling. Advantageous is to arrange the temperature of hot gases before their transition through fluid layer (6), by suction of cool air on value around 850 degrees of Celsius. Fluid combusting device (11) is equipped with fault fume line (15), which is switching the air chamber (4) located under fluid layer (6) with waste material ventilator (10). Advantageously is fluid focus (1) of fluid combustion device (11) equipped with leading of cool air (18).

Description

Technical field

The present invention relates to a method of heating a fluidized bed in commissioning a fluidized bed by means of a running-in burner installed in the furnace space above the fluidized bed and a fluidized bed combustor for carrying out the method.

BACKGROUND OF THE INVENTION

When starting the fluids into operation from a cold state, the fluidized bed must first be heated to at least the ignition temperature of the operating fuel in order to start fuel metering.

Several methods of heating a fluidized bed are known in the operation of a fluidized bed. In the case of low-power fluidized-beds, the heating of the fluidized bed is carried out by means of charcoal. The disadvantage of this method is the gradual formation of the fluidized bed up to the ignition of the charcoal, and it is practically not possible to use it for the foci of higher outputs.

Another method of heating the fluidized bed is to burn an auxiliary fuel in the burner above the bed, e.g. fuel oil or gas and the radiant effect of the flame directed to the fluidized bed heats the bed particles. The disadvantage of this method is only partially the utilization of the released heat in the combustion of the auxiliary fuel, and hence the long hours required for heating the fluidized bed. The most commonly used method of heating the fluidized bed is to heat the fluidized bed with hot gases from a separate special combustion chamber equipped with an oil or gas burner. The high temperature hot gas is fed into the air chamber under the fluidization grate or through the perforated tubes directly into the fluidized bed. The disadvantage of this method is the necessity to install a special combustion chamber made of expensive refractory materials.

Further, a method of heating a fluidized bed is known, which consists in extracting exhaust gases from the fluidized bed space above the fluidized bed where one or more of the incoming burners are installed, which are led into the air chamber below the fluidizing grate or are discharged through perforated tubes. into the fluidized bed. In this process, the exhausted flue gases led into the fluidized bed first pass through the grate, optionally through perforated tubes, and then through the fluidized bed. They pass through the layer in a direction identical to the direction of flow into the incoming combustion air layer. Their maximum temperature is limited by the design temperature of the grate or the design temperature of the perforated tubes. It is not possible to use a higher exhaust gas temperature to accelerate the heating of the fluidized bed. Another disadvantage is the need to install a recirculation fan.

The described methods of heating the fluidized bed are implemented using a variety of fluidized bed combustion devices. A fluidized bed fluidized bed combustion apparatus is known in which an auxiliary incineration burner is positioned above the fluidized bed. The fluidized bed is deposited on a fluidizing bed, under which an air chamber is placed. The air chamber is equipped with a combustion air inlet with a regulation flap and a recirculation pipe inlet. A recirculation pipe is connected from the fluidized bed space, at a point between the fluidized bed and the auxiliary incoming burner, which is connected to the inlet of the air chamber recirculation pipe. A recirculation fan is located in the recirculation screed.

Another known fluid device consists of a fluidized bed and an auxiliary combustion device located within the fluidized bed. The fluidized bed is equipped with an air box which is attached to the hearth under the fluidization grid. The air chamber is equipped with a combustion air supply with a regulation flap. The main combustion air duct with fan is connected to the combustion air inlet of the air chamber. The main combustion air duct is a duct in which a flap is connected to the auxiliary combustion device. The auxiliary combustion device is connected via an outlet pipe to perforated tubes, which are located in the fluidized bed, in the fluidized bed, above the fluidization grid.

SUMMARY OF THE INVENTION

The above-mentioned drawbacks are eliminated by the method of heating the fluidized bed when the fluidized bed is put into operation, in which the hot gases from the incoming burner are sucked through the fluidized bed and at the same time transfer heat. is the flow direction of the combustion air supplied to the fluidized bed. After passing through the fluidized bed, the hot gases are cooled by stirring with air to a temperature of about 25 ° C.

The process according to the invention allows the fluidized bed to be accelerated. It is possible to use hot gas at a temperature higher than that allowed by the design temperature of the grate, and it is not necessary to install a recirculation fan for heating.

It is advantageous to adjust the temperature of the hot gases before passing through the fluidized bed to a temperature of about 850 ° C by sucking in cold air. This protects the grid from exceeding the design temperature, controls the heating time and adjusts the heating uniformity of the fluidized bed.

In essence, a fluidized bed combustion apparatus connected to a flue gas fan is provided with a flue outlet equipped with a shutter flap comprising a fluidized bed with an approaching burner positioned above the fluidized bed, below which is located an air chamber equipped with combustion air inlet with a control flap. is using a short-circuit flue. The short-circuit flue inlet is connected to the air chamber with a shut-off device and the short-circuit flue outlet is connected to the bottom outlet at the point between the shut-off flap and the exhaust fan.

In order to control the temperature of the hot gases prior to entering the fluidized bed, it is advantageous to provide a fluidized bed at the point between the incoming burner and the fluidized bed with a cold air supply with a control air flap.

BRIEF DESCRIPTION OF THE DRAWINGS

The method of heating the fluidized bed during commissioning of the fluidized bed and the fluidized bed combustion apparatus for carrying out the method are explained in more detail with reference to the figures. is a schematic illustration of a combustion apparatus connected to the exhaust fan via an exhaust outlet.

DETAILED DESCRIPTION OF THE INVENTION

The fluidized bed combustion apparatus 11, comprising a fluidized bed 1, is connected to a flue gas outlet 10 via a flue gas outlet 10. The flue gas outlet 16 is equipped with a shut-off flap 12. The fluidized bed 1 is equipped with an incoming burner 2. 5, under which the air chamber 4 is provided with a combustion air inlet 17 with a regulating flap 14. A shorting flue inlet 15 is connected to the air chamber 4. The shorting flue outlet 15 is connected to the exhaust outlet 16 at a point between the shut-off flap 12 and the exhaust fan 10. In the short-circuit flue 15 there is a shut-off device 9. The fluidized bed 1 is equipped with a cold air inlet 18 between the incoming burner 2 and the fluidized bed 6.

With the shut-off flap 12 closed and the shut-off device 9 open, the hot gases generated by the incoming burner 2 are sucked out of the fluidized bed 1 by the exhaust fan 10. At the same time, air is supplied to the fluidized bed 1 above the bed 6; air. The amount of cold air is adjusted by the regulating air flap 13 so that the temperature of the hot gases above the fluidized bed 6 is maintained at about 850 ° C. The hot gases so treated penetrate the fluidized bed 6 and transfer its heat. After passing through the fluidized bed 6, they penetrated the air chamber 4 into the air chamber 4. In the air chamber 4, their temperature is adjusted to about 25 ° C by sucking in the air supplied to the air chamber 4 through inlet 17 and a quantity of about 250 It is regulated by flap 14. From the air chamber 4, the hot gases are discharged through the short-circuit flue 15 and enter the exhaust outlet 16, and are discharged through the exhaust fan 10 into layer 6 which has been heated by the radiant effect of flame and heat transfer from the hot gases. passing through the fluidized bed 6, with the exhaust fan 10 operating, the shutter 12 is open, the shutter 9 is closed, and the combustion air flows into the fluidized bed 6 in the opposite direction to the flow direction of the hot gases from the incoming burner 2. Into service.

Industrial usability

The described method of heating the fluidized bed and the apparatus for performing it is useful for starting up boilers and fluidized bed furnaces.

Claims (4)

PATENT CLAIMS 1. A method of heating a fluidized bed in a fluidized bed operation, wherein the hot gases from the incoming burner are sucked through a fluidized bed, at the same time transferring heat, characterized in that the hot gases are sucked through the fluidized bed in the opposite direction to is the flow direction of the combustion air supplied to the fluidized bed, and after passing through the fluidized bed, the hot gases are cooled by mixing with air to a temperature of about 250 ° C. The fluidized bed heating method of claim 1, wherein the hot gases are cooled to a temperature of about 850 ° C prior to passing through the fluidized bed by sucking in cold air. A fluidized bed combustion apparatus for carrying out the method according to claim 1, connected to a flue gas fan with a flue outlet equipped with a shutter flap, consisting of a fluidized bed with an approaching burner positioned above the fluidized bed. the female of the air chamber (4) being connected to the short-circuit flue (15) inlet with the shut-off device (9), the short-circuit flue (15) outlet being connected to the exhaust outlet (16) at the point between the shut-off flap (12) and the exhaust fan ( 10). The fluidized bed combustion apparatus according to claim 3, characterized in that the fluidized bed (1) is equipped with a cold air inlet (18) with a control air flap (13) at a point between the incoming burner (2) and the fluidized bed (6). .