JPH10169942A - Water cooled structure of tuyere in waste melting furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a quick exchange of the body of a tuyere under hot condition simultaneously while reducing the flow rate of a cooling water in a water cooled structure of a tuyere of a waste melting furnace. SOLUTION: In a tuyere structure where a circulation passage of cooling water is formed independently inside each of a large ring 2 and the body 3 of a tuyere, an inlet of a circulation passage of the large ring 2 is connected to a supply source of the cooling water while an outlet of a circulation passage of the tuyere body 3 is connected to a recovery source of the cooling water. An outlet of the circulation passage of the large ring 2 and an inlet of the circulation passage of the tuyere body 3 are connected by the passage of a closed loop while a branch passage in which cooling water runs toward the recovery source side is provided in the course of the passage. The passage of the closed loop and a branch part of the branch passage are provided with a three-way directional control valve 5 with a port connected to each of these passages.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water cooling structure of a tuyere for feeding a gas such as air or oxygen for combustion into a waste melting furnace.

[0002]

2. Description of the Related Art A waste melting furnace is provided with a tuyere for blowing, for example, combustion air into a furnace bottom side. The tuyere is composed of a large circle which is inserted into and fixed to a mounting opening penetrating the furnace wall, and a tuyere main body which is inserted into the large circle and arranged so that the tip thereof faces the furnace. is there.

[0003] These Daimaru and tuyere main bodies are exposed to the heat in the furnace and become high temperature, so that it is necessary to circulate cooling water from the outside and cool down the water. FIG. 4 schematically shows such a water cooling structure. Conventionally, a cooling water circulation channel is formed inside each of the tuyere main body 51 and the Daimaru 52, and the tuyere main body 51 and the Daimaru In general, a cooling water circulation path 51a, 52a dedicated to 52 is connected.

[0004]

During the operation of the melting furnace,
The furnace temperature at the bottom of the furnace where the pyrolysis residues and the like are deposited is quite high, and the thermal load on the tuyeres arranged for blowing air or oxygen to promote the combustion of the pyrolysis residues is large. For this reason, it is necessary to increase the circulation flow rate of the cooling water necessary for the cooling, and a large proportion of the cooling water for tuyere cooling in the entire cooling water in one melting furnace equipment is high. The facilities of the water system are very large. Also,
Not only the equipment of the water cooling system for tuyere cooling becomes complicated, but also the control and the operation become complicated.

In order to promote the cooling of the tuyere main body 51 and the Daimaru 52, it is effective to increase the flow rate of the cooling water passing therethrough to enhance the heat transfer. With such an operation, the temperature rise of the cooling water between the entrance side and the exit side of the tuyere main body 51 and the Daimaru 52 becomes relatively small. Therefore, even if the tuyere main body 51 and the Daimaru 52 are arranged in series in the circulation path of the cooling water instead of being cooled in separate systems, the cooling capacity for these will not decrease so much. Reduction is also possible.

On the other hand, since the tuyere main body 51 faces the inside of the furnace, the heat load is much larger than that of the Daimaru 52, so that the tuyere body 51 is exchanged more frequently than the Daimaru 52. Such replacement of the tuyere main body 51 is preferably performed when the melting furnace is stopped, but the frequency of hot replacement during operation is high.

However, if the tuyere main body 51 and the Daimaru 52 are arranged in series in the circulation path of the cooling water as described above, the supply of the cooling water to the tuyere main body 51 is stopped and the cooling of the Daimaru 52 at the same time. Will also stop. For this reason, the large circle 52 remains uncooled until the tuyere main body 51 is replaced, and a situation such as melting is caused.

[0008] As described above, in the cooling of the tuyere in the conventional waste melting furnace, if the tuyere main body and the Daimaru are individually cooled, it is necessary to secure the flow rate of the cooling water. If it is arranged in series with the tuyere, there is a problem in that the tuyere main body is exchanged hot.

The problem to be solved in the present invention is to make it possible to reduce the flow rate of the cooling water in the water cooling structure of the tuyere of the waste melting furnace and at the same time to quickly exchange the tuyere body hot. It is in.

[0010]

According to the present invention, there is provided a large circle which is disposed through a furnace body of a waste melting furnace from outside, and a tuyere which is inserted into the large circle and blows air or the like into the furnace from outside. And a tuyere water cooling structure in which a cooling water circulation flow path is independently formed inside each of the Daimaru and the tuyere main body. At the same time, the outlet of the circulation channel of the tuyere body is connected to the cooling water recovery source, and a closed loop channel between the outlet of the Daimaru circulation channel and the inlet of the circulation channel of the tuyere body is used. In the middle of this flow path, a branch flow path is provided toward the cooling water recovery source side, and a port is connected to each of these flow paths at the branch of the closed loop flow path and the branch flow path. A switching valve is provided.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION If a cooling water flow path is formed in one direction in each of the Daimaru and the tuyere body, cooling is performed by connecting a cooling water supply pipe and a reflux pipe to respective inlets and outlets. A water circulation channel can be configured. Then, the two ports of the three-way switching valve are connected in the middle of the loop-shaped flow path provided between the Daimaru outlet and the tuyere main body inlet, and the remaining ports are connected to the branch flow path toward the cooling water recovery side. By connecting the three-way switching valve, it is possible to switch the system from Daimaru to the collection side via the tuyere main body and the system from Daimaru to the collection side directly.

[0012]

1 is a longitudinal sectional view showing a main part of a melting furnace having a tuyere water cooling structure according to the present invention, and FIG. 2 is a plan view showing a main part of FIG.

In the figure, a mounting port 1 penetrating a furnace body 1 is shown.
A large circle 2 is inserted into and fixed to a, and a tuyere main body 3 is coaxially detachably incorporated in the large circle 2.

The large circle 2 has a concave cross section fixed with its peripheral wall fitted to the mounting opening 1a, and has a cooling water circulation passage formed therein. A cooling water supply pipe 2a and a reflux pipe 2b are connected to this circulation flow path, and the cooling water from the supply pipe 2a is discharged from the reflux pipe 2b after circulating through the circulation flow path in the Daimaru 2.

As shown in FIG. 1, the tuyere main body 3 has a shape whose tip projects from the large circle 2 to the inside of the furnace body 1, and has an air supply pipe 4 connected to the base end thereof. A cooling water circulation channel is formed inside the tuyere main body 3 in the same manner as the Daimaru 2, and a cooling water supply pipe 3 a and a reflux pipe 3 b are connected to this circulation channel, respectively.

FIG. 3 is a schematic diagram showing a cooling water supply / circulation system for the Daimaru 2 and the tuyere main body 3.

The above-mentioned supply pipe 2a is one in which the water supply source is directly connected to the inlet of the circulation flow path of the Daimaru 2, and the return pipe 2b connected to the outlet of the circulation flow path is three-way without going to the drain side. It is connected to one port 5b of the switching valve 5. on the other hand,
The supply pipe 3a connected to the inlet of the circulation flow path of the tuyere main body 3 has its base end connected to another port 5a of the three-way switching valve 5, and the reflux pipe 3b from the outlet of the circulation flow path is reversed halfway. The stop valve 6 is arranged and directly connected to the drain side. A branch pipe 7 is connected to the reflux pipe 3b downstream of the check valve 6 and connected to the remaining port 5c of the three-way switching valve 5.

In such a cooling water circulation system, Daimaru 2
When cooling both the tuyere body 3 and the tuyere main body 3, the ports 5a and 5b of the three-way switching valve 5 communicate with each other, and the port 5c
Operate the side to close. Thereby, the cooling water from the supply pipe 2a connected to the water supply source first goes around the inside of the Daimaru 2 and then goes from the reflux pipe 2b to the three-way switching valve 5 side,
After passing through the ports 5b, 5a, it is supplied to the tuyere main body 3 from the supply pipe 3a. Then, the cooling water that has flowed out of the circulation flow path of the tuyere main body 3 is sent out from the return pipe 3b to the drainage side.

As described above, the cooling water from the supply pipe 2a is also used for cooling the tuyere main body 3 after cooling the Daimaru 2, so that the cooling water from the common water supply source and the Daimaru 3 are cooled. The mouth body 3 can be arranged in series. Therefore, only one cooling water supply circulation system can be provided, and the cooling equipment can be simplified. If the speed of the cooling water is set higher, the temperature rise of the cooling water can be suppressed even after the Daimaru 2 is cooled.
There is no hindrance to cooling the refrigeration system.

When the tuyere main body 3 is replaced, the three-way switching valve 5 is operated so that the ports 5b and 5c communicate with each other to cut off the flow path to the supply pipe 3a connected to the tuyere main body 3. Thereby, even if the supply of the cooling water from the water supply source is continued, the cooling water flowing from the Daimaru 2 to the reflux pipe 3a is sent out from the three-way switching valve 5 to the drain side via the branch pipe 7. The flow of the cooling water sent from the branch pipe 7 to the reflux pipe 2 b is blocked by the check valve 6 toward the tuyere main body 3.

By operating the three-way switching valve 5, only the large circle 2 can be continuously cooled, and the tuyere body 2 can be replaced hot, which affects the operating rate of the melting furnace. Will not be exerted.

[0022]

According to the present invention, it is possible to circulate the cooling water in order from the Daimaru to the tuyere main body only by operating the three-way switching valve, and a cooling system is provided for each of the Daimaru and the tuyere main body as before. As compared with the case where the cooling water is provided, the cooling equipment is simplified, and the amount of cooling water can be significantly reduced, so that the equipment can be further simplified.

Further, even when the tuyere main body is replaced, the cooling water can be continuously circulated through the Daimaru, so that the hot tuyere main body can be exchanged hot and the operating efficiency of the waste melting furnace can be improved. Does not affect

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a waste melting furnace having a tuyere water cooling structure according to the present invention.

FIG. 2 is a plan view showing a main part of FIG. 2;

FIG. 3 is a schematic diagram showing a cooling water supply / circulation system for the Daimaru and the tuyere body.

FIG. 4 is a schematic diagram of a conventional cooling water supply system for tuyeres.

[Explanation of symbols]

 1: Furnace body 1a: Mounting port 2: Daimaru 2a: Supply pipe 2b: Reflux pipe 3: Tuyere body 3a: Supply pipe 3b: Reflux pipe 4: Air supply 5: Three-way switching valve 6: Check valve 7: Branch pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shunji Yamauchi 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu Nippon Steel Plant Design Co., Ltd. Nippon Steel Plant Design Co., Ltd.

Claims (1)

[Claims] 1. A daimaru which is disposed through a furnace body of a waste melting furnace from the outside and a tuyere body which is inserted into the daimaru and blows air or the like into the furnace from the outside. A tuyere water cooling structure in which cooling water circulation passages are independently formed inside each of the mouth main bodies. The inlet of the Daimaru circulation passage is connected to a cooling water supply source and the tuyere main body circulation is performed. The outlet of the flow path is connected to the cooling water recovery source, and the outlet of the circulating flow path of the Daimaru and the inlet of the circulation flow path of the tuyere body are connected by a closed loop flow path, and in the middle of this flow path Is provided with a branch flow path toward a cooling water recovery source side, and a closed loop flow path and a branch portion of the branch flow path, and a three-way switching valve having a port connected to each of these flow paths at a branch. Water cooling structure of tuyere in melting furnace.