JPS6082779A - Method of sealing sintering machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sealing a Dwight Lloyd type sintering machine.

The sintering method has become widely used as a method for agglomerating fine ore, and
Page) Dwight Lloyd type sintering machines are often used as this mass production equipment. This Dwight Lloyd type sintering machine is the first
As shown in the figure, raw material 2 is supplied to pallets 1 that are connected endlessly, the surface of the raw material is ignited in an ignition furnace 3, and gas is sucked into the pallet 1 toward a group of 4 wind boxes provided at the bottom of the pallet 1. The pallet 1 can be moved from the raw material feed section 5 to the cake discharge section 6 in accordance with the firing speed so that the fuel in the raw material 2 is combusted and sequentially fired from the surface toward the wind box 4. ing. Furthermore, the baked cake 7 discharged from the cake discharge section 6 is crushed by a crusher 8, and then charged into a cooler pallet 9 that moves in the same way as the baked strands, and by suctioning or pushing gas from the cooler 2-wind box IO. The crushed baked cake 11 is cooled. Note 1
2 is an exhaust fan, and 13 is a chimney.

In recent years, from the perspective of energy conservation, some sintering machines have installed a boiler 14 in each exhaust gas line as shown in Figures 2 and 3 to recover heat from the exhaust gas. Another method is to return it to fired strands. In addition, some systems divide the main exhaust gas windbox line into multiple blocks for suction, separate them into a high-temperature gas section and a low-temperature gas section, and install a boiler 14 in the high-temperature gas section for heat recovery. Since the mold sintering machine is of a continuous movement type as described above, productivity is extremely good. However, as the pallet moves, a gap is created between the pallet 1 and the wind box 4. So-called leakage W1, in which air does not enter the wind box 4, but directly enters the wind box 4 from the atmosphere through a gap in the sealer 15, which is vertically movably inserted under the bottom of the pallet 1, as shown in FIG. 4, for example. Alternatively, as shown in FIG. 5, there are air leaks W2 that directly enter the wind box 4 from the front surface of the pallet 1 in the cake discharge section 6, and these account for about 30 to 40 inches of the main sintering air exhaust volume. ing. This leakage not only sucks in unnecessary air and increases the power of the main exhaust fan, but also has the disadvantage of lowering the temperature of the sintering exhaust gas.

This is because the air leakage sucks in the atmosphere, diluting the sintering main exhaust gas, which is also hotter than the atmosphere, and lowering the temperature. Decreasing the amount of heat recovery steam in the boiler 14,
There is a problem in that the low-temperature main exhaust gas containing 80M gas promotes sulfuric acid aggregation and promotes corrosion of equipment.

The present invention solves these conventional problems,
In order to not only reduce the amount of air leakage that enters through the gap between the pallet and the wind box, but also to increase the temperature of the air leak, gas with a temperature of 100℃ or more is sent into the hood, which is a partition wall that covers the gap between the pallet and the wind box. It is something.

The sealing method of the present invention will be explained in detail below with reference to the drawings.

First, as mentioned above, there is a pressure difference between the wind box and the atmosphere, and this pressure difference causes the air to be sucked into the gap between the pallet and the wind box. ), the inventor found out that there is a relationship shown by equation (1) (5th Tei), and found that if the temperature of the sucked gas is high, the amount of air leakage can be reduced, as shown in Figure 6. confirmed.

Q=, Kv City・273/T ・'・−・・(1) However
Q is the amount of air leakage (Nm3) △pH The pressure difference between the wind box and the atmosphere (smI (2
0) T is the leakage gas temperature (°K) K constant This means that if the gas temperature is high, the same mass of gas will expand, and if the ventilation resistance is not high, the amount of air leakage will be reduced. Therefore, for example, sintering main exhaust gas or cooler exhaust gas is used as the high-temperature gas, and by sucking these high-temperature gases through the gap between the pallet and the wind box, the amount of air leakage can be reduced, and the temperature of the air leakage can be lowered to the atmosphere. By increasing the temperature of the exhaust gas, the temperature of the main exhaust gas mixed in the wind box is raised higher than before. This achieves a reduction in air leakage,
Not only can the power of the main exhaust fan be reduced, but also the overall temperature increases in the sintering main exhaust heat recovery (page 6), making it possible to increase the amount of heat recovery.

Of course, the purpose of the hood in the method of the present invention can be achieved as long as it is separated from the atmosphere, so it may cover the entire fired strand. Furthermore, the above object can be achieved by applying the method of the present invention to a product in which a fired strand and a cooler strand are integrated.

Note that the reason for limiting the gas temperature to 100℃ or higher is 1.
This is because the above effects are poor at temperatures below 00°C.

In addition, as the gas to be introduced, we used sintering main exhaust gas and cooler gas, which are readily available and have a temperature of 100°C or higher, but any gas that is safe and non-corrosive and has a temperature of 100°C or higher may be used.

Next, the method of the present invention will be explained using examples.

In the Dwight Lloyd type sintering machine shown in FIG. 7, a partition hood 16 as shown in FIG.
When the cooler exhaust gas from the wind box 10 of the cooler strand is heat-recovered via the boiler 12 and then introduced into the bulkhead hood 16 provided on the firing strand (page 7) to perform the firing operation (A
), and as shown in FIG. 9, the exhaust gas from the cooler strands is guided into a hood 17 which covers the entire upper part of the pallet 1 of fired strands and whose lower end of the side wall is closely fixed to the wind box 4, as shown in FIG. When the operation is carried out (B) and as shown in Fig. 11, the conventional hood 18
A comparison was made between the case where the cooler exhaust gas was recovered into the atmosphere in the same manner as shown in FIGS. 7 and 9, and then released into the atmosphere. The results of the operating specifications at that time are shown in Table 1. By applying the method of the present invention, the air flow rate could be reduced by 13q6 in method A) and 14 factors in method (B).

Table 1 Next, as shown in Fig. 12, the four groups of wind boxes for the fired strand are separated into two groups of wind boxes, the high temperature main exhaust gas near the cake discharge section 6 is collected, and after heat recovery,
A comparison was made between the method of the present invention shown in FIG. 1O and the conventional method when returning the strand to a fired strand. The operating specifications at this time are shown in Table 2.

Table 2 (Page 9) As shown in Table 2, by applying the method of the present invention, the p1 air flow rate can be reduced by approximately 17%, and the amount of heat recovered steam in the main exhaust and cooler can be reduced. We were able to increase approximately 40q6.

As described above, the method of the present invention is extremely effective in reducing the amount of air leakage and increasing the amount of waste heat recovery steam, and has excellent effects.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are schematic diagrams of the conventional Dwight Lloyd sintering machine, Figures 4 and 5 are explanatory diagrams showing the state of air leakage in the conventional sintering machine, and Figure 6 is the same. The relationship curve between the suction gas temperature and the amount of air leakage, FIG. 7 is an explanatory diagram showing one embodiment of the method of the present invention, FIG. 8 is a cross-sectional view of the sealing part, and FIG. 9 is another implementation of the method of the present invention. An explanatory diagram showing an example, FIG. 10 is also the l...wind box of fired strand,
2...Pallet of fired strands, 9...Cooler pallet, IO...Cooler wind box, 1
6... Sealing part (Page 10) Bulkhead hood, 17°・°Sealing part hood voluntary procedure amendment 1. Indication of the case 1982 Patent Application No. 191750 2, Name of invention Seal method for sintering machine 4, Attorney's amendment Patent Application No. 1981-191759 1, F! Book A, page 9, lines 18 to 19 [1...
・Firing... strand), J'I'r
Corrected as ``l・-m-formed Nutland's/metallet, 4...fired strand's wind potsukunu''. Patent applicant: Sumitomo Metal Industries, Ltd. Agent: 1) Good

Claims (2)

[Claims] (1) Sintering in a Dwight Lloyd type sintering machine, characterized in that the seal between the firing strand wind box and the moving pallet is separated from the atmosphere by a hood, and a gas with a temperature of 100° C. or higher is sent to the 7-door Ic. How to seal the machine. (2) The method for sealing a sintering machine according to claim 1, wherein the hood covers the upper part of the pallet and the lower end of the side wall is closely fixed to the wind box. (The method for sealing a sintering machine according to claim 1 or 2, wherein the gas having a temperature of 31,100° C. or higher is sintering main exhaust gas or cooler exhaust gas.