JPS6050269B2 - Jet flow continuous industrial kiln - Google Patents

Description

Detailed Description of the Invention This invention employs a forced circulation method for atmospheric gas in the furnace, and improves hot gas circulation efficiency within the furnace, and [jet type] enables uniform heating or uniform cooling within the furnace. Concerning continuous industrial kiln furnaces.

Conventionally, a suction circulation method for combustion gas has been adopted, in which partition walls with combustion gas inlets and outlets facing each other are provided on both side walls of the preheating zone, firing zone, cooling zone, etc., and a cooling zone is provided outside the side walls. The partial circulation type is equipped with a blow-off duct that uses a blower to push cold air, and a blow-off duct that collects heated air using a suction and blower in the firing zone and preheating zone, and blows out the heated air to each block. There is an industrial kiln (see Special Publication No. 39-329). In order to circulate the gas inside the furnace, this conventional system sucks the gas inside the furnace into each combustion and temperature control chamber, which are divided by partition walls facing each other, and then returns it to the inside of the furnace. The above-mentioned combustion gas is sent, and the combustion gas is circulated in a local loop in each of the blocks facing each other with the center of the furnace as a boundary, so that the direction of the flow of the combustion gas in the combustion chamber is adjusted to the heating or firing rate. The direction of travel is parallel to the direction of travel.

For this reason, the circulation of combustion gas in the furnace is simply that gases at the same level move horizontally and circulate, and there are extremely few opportunities for combustion gases located at the upper and lower parts of the furnace to mix with each other. Uniform stirring in the zone cannot be obtained. Also, the combustion gas is sucked into each combustion and temperature control chamber,
The means for discharging the combustion gas from the chamber into the furnace again is a simple one that simply circulates the combustion gas, but the circulation efficiency is still insufficient, so the combustion gas in the combustion and temperature control chamber is As a result, the number of circulations of the combustion gas decreases. This invention was made in order to eliminate the above-mentioned drawbacks, and its purpose is to increase the temperature of the upper and lower parts at the same position in the furnace in both the pre-heating zone and the cooling zone, or in either one of them. By eliminating the difference by 7), the hot gas in the furnace is strongly stirred, the number of times the hot gas is circulated is increased, and the hot gas circulation efficiency is greatly improved, resulting in a uniform temperature distribution as a whole. An object of the present invention is to generally provide a jet-type continuous industrial kiln that can be obtained. An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show a front sectional view, a side sectional view, and a plan sectional view, respectively, of a preheating zone A in a continuous industrial kiln.

1 represents the left and right side walls of the furnace, 2 represents the ceiling of the furnace, 3 represents the cart, and 4 represents the inside of the furnace.

Reference numeral 5 denotes a closed space armhole provided vertically along both side walls 1, 1, the top part 5a of which is high enough to reach near the ceiling part 2 of the furnace, and the bottom part 5b of which is located at the lower part of the furnace interior 4, that is, the trolley. It is formed to a depth approximately comparable to the upper surface 3a of No.3.

The sleeve chambers 5 installed in the side wall 1 are arranged so that the left and right sides thereof are staggered with respect to each other, as shown in the third figure. In this way, sleeve room 5
We decided to arrange them in a staggered manner on the ceiling 2 of the furnace interior 4.
A suction hole 6, which will be described later, is provided in the upper part of the sleeve chamber 5 to supply high-temperature gas.
The high-temperature hot gas introduced into the sleeve chamber 5 is used directly or stirred with outside air to form a hot gas, and a blow-off hole 7 (described later) is provided at the lower part of the sleeve chamber 5. When the hot gas is forcibly blown out through a forced circulation fan 9 or an injector 8, which will be described later, and the hot gas after blowing out is blown toward the opposing side wall 1, the hot gas hitting the opposing side wall 1 is The hot gas in the furnace 4 that rises along the side wall and reaches the ceiling 2 of the furnace and is sent along the ceiling is again forced into the sleeve chamber 5 through the suction hole 6 in the sleeve chamber. In this way, the gas is strongly swirled in one direction in each arm chamber, and the arm chambers facing the arm chamber in a staggered plane are... The hot gas swirls in completely opposite directions, and throughout the preheating zone, the swirling flows of hot gas alternate in opposite directions in each sleeve chamber, and the gas flows cancel each other out by adjacent swirling gas flows. The hot gas in the upper and lower parts of the furnace is sufficiently stirred in each arm chamber to prevent This is to ensure that Reference numeral 6 denotes suction holes provided in the upper part of the inner side of the sleeve chamber 5, facing right sideways in the oven width direction, and as shown in FIGS. 2 and 3, for example, six holes are provided.

Reference numeral 7 denotes a blow-off hole provided at the inner lower part of the sleeve chamber 5, that is, at a position at or above the top surface of the trolley 3, facing directly across from the furnace width, as shown in FIGS. 1 and 3. For example, two holes are provided.

8 is an injector installed vertically downward at the upper part of the sleeve chamber 5, that is, slightly below the suction hole 6, and the tip of the nozzle 8'' of the injector is located below the suction hole 6. There is.

The cross-sectional shape of the nozzle 8'' of the injector 8 is, as shown in FIG. As shown in FIG. 4b, a diffuser 10 made of refractory brick is attached to the section, and the diffuser 10 not only uses the injection force of the injector 8 but also the suction hole 6 and the inside of the sleeve chamber 5 in the vicinity. The pressure is actively reduced to further increase the suction power.The jet stream passing through the injector 8 passes outside air, exhaust gas in the furnace, or a mixture of both into the injector 8. FIG. 5 shows a case where a heat-resistant forced circulation fan 9 is installed in place of the injector 8.

This forced circulation fan 9 is satisfied by adopting a propeller type axial flow system. Next, FIG. 6 is a front view showing the case where the injector 8 is installed in the sleeve chamber 5 formed on both side walls 1, 1 of the cooling zone B.

The arrangement of the sleeve chambers, the mounting direction of the injector, etc. are not particularly different from those of the preheating zone A, but the blow-off holes 7 formed at the bottom of the sleeve chamber 5 are arranged in several stages in the vertical direction to enhance the cooling effect. It differs in that it is divided into Example The hot gas suction hole to the furnace side sleeve room of the preheating zone was 12CknW x 1.
39W$LH x 6 pieces (area: 0.10008㎡), 120wrmW hot gas blowout hole into the furnace from the sleeve chamber in the furnace side wall
×2757TUnH×2 pieces (area: 0.06600 i)
If the jet air flow from the injector nozzle has a temperature of 300°C, an air flow rate of 107 T1/min (At3OO°C), and a static air pressure in front of the nozzle of 240 TmH20 (At3OO°C), the hot gas temperature at the ceiling in the furnace is 700°C, As a result of measuring the hot gas suction relationship at 900°C and 1100°C, the amount of hot gas suctioned into the ceiling of the furnace, the amount of mixed gas, the speed of blowing mixed gas into the furnace, and the suction rate of the injector all increased. Furthermore, it was found that the number of hot gas circulations also increased.

It was found that as the suction rate of the injector and the number of hot gas circulations increased, the hot gas was forcibly stirred in the upper and lower parts of the furnace, and an atmosphere with a uniform temperature could be quickly obtained. As can be seen from the above description, this invention comprises discontinuously disposing sleeve chambers in a staggered plane on both side walls of the furnace body of both or one of the preheating zone and the cooling zone of a continuous industrial kiln. , each sleeve chamber has a plurality of suction holes formed in its upper part that communicate with the upper part of the furnace in the direction of the furnace width, and a plurality of suction holes that communicate with the lower part of the furnace in the direction of the furnace width in the lower part of each sleeve chamber. Since each of the air outlet holes is formed, and a downward forced circulation fan and/or injector is provided at the upper part of the sleeve chamber, the suction hole and the sleeve chamber near the suction hole are actively depressurized. This reduced pressure state, together with the forced circulation fan in the sleeve chamber and the injection force from the injector, further increases the suction force, and thoroughly stirs the jet stream and the hot suction gas in the sleeve chamber to produce hot gas at a uniform temperature. you can get
This hot gas is strongly blown out from the blow-off hole in the lower part of the sleeve chamber toward the lower part of the furnace in the width direction of the furnace, hits the other side wall, and along the side wall, both the hot gas and the hot gas around the inside of the furnace are blown out. The gas stream rises while being rolled in, reaches the ceiling of the furnace, and the gas flow swirling along the ceiling of the furnace is sucked into the suction hole again, and the above movement is repeated one after another, creating a strong swirl in the same direction in each sleeve chamber. This will result in a flow.

In addition, since the arm chambers are arranged in a staggered plane on both side walls, the swirling gas flow in the arm chambers facing each other in a staggered plane swirls in opposite directions. In either or both cooling zones,
A uniform atmosphere is obtained with no temperature difference between the upper and lower parts of the furnace, and the preheating and cooling effects can be further enhanced. Therefore, it is expected that the hot gas circulation efficiency within the furnace will be greatly improved, and in particular, a system in which the hot point is mounted in the central lower part of the furnace, that is, on a trolley, by utilizing the powerful hot gas jetting force from the circulating hot gas blowout hole. It has a unique effect that has not been seen before in that it can reach the lower center of the incoming product group and raise the heat in the area that is likely to have a low fever.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a front sectional view of the preheating zone, Fig. 2 is a side sectional view thereof, Fig. 3 is a plan sectional view thereof, and Fig. 4a is a sectional view of the injector nozzle. Figure, 4th
Figure b is a sectional view of the diffuser, Figure 5 is a front sectional view when a forced circulation fan is installed, and Figure 6 is a front sectional view of the cooling zone. 1...Side wall, 2...Ceiling, 4...
...Furnace interior, 5...Sleeve chamber, 6...Suction hole, 7...Blowout hole, 8...Injector,
9... Forced circulation fan.

Claims (1)

[Claims] 1. In a continuous industrial kiln, sleeve chambers are arranged discontinuously on both sides of the furnace body of both the pre-heating zone and the cooling zone, or either one of them, so as to form a staggered planar pattern, and each of the sleeve chambers is disposed in the upper part of the furnace body. Forming multiple suction holes that communicate with the upper part of the furnace in the width direction of the furnace,
A plurality of blow-off holes communicating with the lower part of the furnace in the width direction of the furnace are formed in the lower part of each sleeve chamber, and a downward forced circulation fan and/or an injector are provided in the upper part of the sleeve chamber. A jet-type continuous industrial kiln featuring: