JPS587910B2 - Intrusion air prevention device in industrial furnaces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing outside air from entering through an opening in an industrial furnace, such as a heating furnace.

Conventionally, in the heating furnace 1, the heated material 2 is passed through the extractor 4 by opening the extraction door 3, as shown in FIG.
is extracted onto the extraction table by .

As shown in FIG. 2, the heating furnace 1 is normally provided with an extractor insertion port 5, ie, an opening through which an extractor ram can be inserted and removed, in the lower furnace wall 1'.

Normally, when operating a heating furnace, pressure is applied inside the furnace to prevent air from entering, so that the pass line of the material to be heated is 0mm/0mm.
Since the water column is maintained, the pressure inside the furnace becomes negative below the pass line, so if there is an opening, outside air will enter.

On the other hand, above the pass line, the furnace pressure becomes positive and the furnace gas is blown out.

If you try to operate the furnace while maintaining a high pressure inside the furnace to reduce the amount of air that enters below the pass line, the ejection of combustion gas from inside the furnace will increase, which will not only reduce thermal efficiency, but also cause the surrounding equipment to burn out due to the ejected gas. This method naturally has its limitations, as it can cause problems and significantly worsen the working environment.

Problems caused by a large amount of intruding air significantly deteriorate thermal efficiency and increase nitrogen oxides generated during combustion, causing environmental problems.

Therefore, reducing the amount of intruding air becomes an extremely important issue in energy saving and environmental measures.

As mentioned above, controlling the heating furnace pressure alone is not effective in preventing air from entering from the openings below the pass line, so in the present invention, the intrusion of outside air from the openings of the heating furnace is hydrodynamically prevented. The present invention provides a device for preventing the above.

In the present invention, a nozzle pipe is provided in an extractor insertion port provided in an industrial furnace, for example, a heating furnace, and a jet nozzle directed to the outside of the furnace is disposed in the nozzle pipe, and a fluid is jetted from the jet nozzle. so that the fluid is focused on the ram insertion line and the focused fluid moves out of the furnace.

The ejector blows out some combustion gas (inside the furnace), and the suction pressure caused by this blowout effect balances the pressure inside the furnace and prevents outside air from entering.

In this case, even if some combustion gas is blown out of the furnace by the ejector, it can be ignored compared to the thermal effect caused by the intruding air, and furthermore, the blown out can be minimized by controlling the amount of ejector fluid, so the present invention This preventive device is extremely effective.

An embodiment of the present invention will be described below with reference to the drawings.

In the present invention, as shown in FIG. 1, numeral 1 indicates the entire heating furnace.

Reference numeral 1' indicates a lower wall of the heating furnace, 2 indicates a material to be heated, 3 indicates an extraction door of the heating furnace, 4 indicates an extractor, and 5 indicates an extractor insertion port for allowing the extractor 4 to enter and exit.

In the present invention, the extractor search port 5
The nozzle pipe 6 is arranged along the.

Reference numeral 7 denotes an ejection nozzle arranged in the nozzle pipe 6, and the fluid ejected from the ejection nozzle 7, such as air or steam, is ejected and focused in the direction of the arrows in FIGS. 3 and 6.

This jetting effect causes the suction pressure to balance the pressure inside the furnace and prevent outside air from entering.

In this case, in order to minimize the consumption of the ejected fluid, one effective means is to increase the area of the ejecting nozzle 7 toward the lower part of the furnace body.

That is, since the degree of negative pressure in the furnace becomes higher in the lower part of the furnace, it is sufficient to equip the equipment with a fluid ejection distribution commensurate with this.

Also, when the material to be heated is not extracted, the heating furnace opening is closed to the extraction door 3.
At this time, it is advantageous to shut off the ejected fluid in terms of fluid consumption and to prevent fluid from flowing into the furnace.

In this case, as shown in FIG. 5, it is also possible to continue the door opening/closing signal 8 to the cutoff valve 10 of the jetting fluid piping 9 to automatically open and close the fluid jetting.

As described above, the present invention has a remarkable effect of solving various problems caused by intruding air and also greatly helping to prevent the generation of NOx and other pollution.

In the present invention, an effective method is to provide a guide plate 11 downstream of the jet as shown in FIG. 7 to reduce loss due to radiant heat from the inside of the furnace to the outside of the furnace. Of course, the effect of the plate 11 is due to the ejector effect.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view of the entire heating furnace, Fig. 2 is a front view of the heating furnace, Fig. 3 is a BB view in Fig. 2, and Fig. 4 is an A-A in Fig. 3. FIG. 5 is a view taken along line CC in FIG. 2, and FIGS. 6 and 7 are plan sectional views of the present invention. 1... Heating furnace, 2... Heated material, 3... Extraction door, 1'...
Lower furnace wall, 4...Extractor, 5...Extractor insertion port, 6...Nozzle pipe, 7...Ejection nozzle nozzle, 8...Door opening/closing signal, 9...Ejection fluid piping, 10...Shutoff valve , 11...Guide plate.

Claims (1)

[Claims] 1. A nozzle pipe is arranged along the extractor ram insertion port provided in the lower furnace wall of the industrial furnace opening, and the nozzle pipe is directed outside the furnace so that the fluid to be injected is focused on the ram insertion line. An intrusion air prevention device for an industrial furnace, characterized by having a blow-out nozzle arranged therein.