SU1404532A1 - Method of heating a furnace with injection burners - Google Patents

Abstract

The invention relates to a technique for burning fuel in furnaces, in particular thermal bell-type ones. The goal is to increase the operational safety and efficiency of burning fuel. The method of heating with the use of injection burners turns on the gas supply to the burners in a pulsed mode .. The difference is that the pressure in the furnace is reduced before the start of gas supply to the burners and the pressure in the furnace is increased after the gas supply is cut off. Gas supply to the burners starts within 1.0-2.0 seconds after the start of pressure reduction in the furnace, and pressure increases start within 1-2.5 seconds after cutting off the gas supply to the burner. The pressure in the furnace is controlled by an air ejector or a mechanical gate. The interval from the cutoff of the gas to the beginning of the pressure increase is inversely related to the temperature change in the furnace, and at a temperature of 300-350 ° C this interval is maintained within 2-2.5 s, and at a temperature of 650-700 ° C within 1.0-1.5 s. 2 3.p. f-ly, 1 ill. (L 4 O 1 O1 SlaE

Description

This invention relates to a technique for burning fuel in furnaces, in particular thermal ones.

The purpose of the invention is to increase the reliability and efficiency of the furnace.

The drawing shows an oven with injection burners.

In the furnace 1, the main and pilot burners 2 and 3 are installed. The pilot burners 3, in particular, the injection burners, can be equipped with electric ignition and flame control devices. The main burners 2 receive gas through line 4, equipped with a shut-off valve 5 and a control valve 6, in front of the burners 2 there are shut-off valves 7.

Pilot burners 3 are supplied with gas through line 8, fitted with a shut-off valve 9. In front of pilot burners 3, there are shut-off valves 10, B of the flue-outlet channel 11 of the furnace i there is an air ejector 12, into which active air flows through line 13, equipped with a flap 14 and a control valve 15.

A temperature sensor 16 mounted in the furnace 1 is connected to the regulator.

17 temperature, which is through the relay

18 and 19 signal delays are associated with. the actuator 20 of the control valve 6, as well as with the actuator 21 of the control valve .15. The regulator 17c, using relays 18 and 19, can change the time delay of the gas cutoff relative to the cutoff of the air supply to the ejector 12 and the switching on of the gas supplies relative to the air supply to the ejector 12.

 During operation, with the shut-off valve 9 open, opening the shut-off valve 10, gas is supplied via line 8 to the pilot burners 3, igniting and: controlling the torch with devices (not shown).

Open the shut-off valve 5 and the shut-off valves 7, turn on the temperature controller, which sends a command to the actuator 21 to open the control valve 15 to supply ejecting air through line 13 to the ejector 12 installed in the hole 1

0

five

five

0

50

five

burners 2

in which air duct already occurs, a combustible mixture is formed, which is ignited by the torch of pilot burner 3.

During operation, the temperature sensor 16 measures its true value, which is compared in the controller 17 with the set value. According to their mismatch, the controller 17 issues commands through the relays 18 and 19 to the actuators 20 and 21 to open or close the valves 6 and 15, respectively. venno. Moreover, valve 15 first opens, and then valve 6. Conversely, valve 6 is closed first, and then valve 15.

The valve 14 allows you to set a predetermined air flow to the ejector 12, set the required pressure in the furnace 1. With the help of the temperature controller 17 and the relay 1.9, you can set a different time interval when the burners are turned off. Since the conditions for the after-burning of products of incomplete combustion deteriorate with decreasing temperature in the Furnace, the closing time of the valve 15 relative to the valve 6 should increase, i.e. this time should be inversely related to the temperature in the furnace.

As shown by experiments conducted on a bell furnace, during transients of switching on and off the burners, prior to the beginning of the supply of gaga to the burners, the pressure in the furnace decreases, and after the gas supply is cut off, the pressure in the furnace increases, creating a 1.3- 1.38. The gas supply to the burners should be started after 1.0-2.0 s after the start of pressure reduction in the furnace, and after the gas supply is cut off, the pressure in the furnace should be increased after 1.0-2.5 s.

Claims (3)

1. The method of heating a furnace with injection burners, which includes the supply of gas and air to the burners in a pulsed mode, combustion, and the selection of products. Combustion through the furnace, characterized in that, in order to increase stove mover 1. With a delay of 5 efficiency, during relay 18, the regulator 17 sends a command to the actuator 20 to open the control valve 6. At the same time, the gas enters 4 the processes of switching on and off of the burners, before starting the gas supply to the burners, reduce the pressure in the furnace, and after the gas supply is cut off, the pressure  efficiency, during the the processes of switching on and off of the burners, before starting the gas supply to the burners, reduce the pressure in the furnace, and after the gas supply is cut off, the pressure in the furnace, an excess air ratio in the range 1.3-1.38 is increased in the burners. 2. The method according to claim 1, characterized in that the gas supply to the burners is carried out in 1.0-2.0 seconds after the start of pressure reduction in the firing process in the furnace, n 1.0-2.5 seconds are started. 3. The method according to claim 1, which relates to the fact that the gas cut and the start of firing in the furnace change, depending on the change in the furnace, than chi, and after the cutoff of the gas supply, less pause and vice versa Compiled by G.Nazarova Editor N. Yatsola Tehred L.Oliynyk Order 4341 Circulation 545 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 The treatment in the furnace starts to increase after 1.0-2.5 seconds. 3. The method according to claim 1, which means that the pause between the gas cut-off and the beginning of the pressure increase in the furnace is changed in inverse proportion to the temperature change in the furnace, the higher the temperature, less pause and vice versa Proofreader M. Demchik Subscription