JPS6239077Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a gas cutoff valve that shuts off the outflow of crude coke gas from a coke oven in equipment for recovering and reusing the sensible heat of crude coke gas generated in a coke oven. It is something.

Conventionally, high-temperature crude coke gas (hereinafter referred to as crude COG) generated in a coke oven is brushed with water near the outlet of the coke oven, cooled to about 80℃, and then sent to gas purification equipment through a dry main. was. However, in recent years, amidst the trend toward resource and energy conservation, research has been underway to recover and reuse the sensible heat of high-temperature (500°C to 800°C) crude COG, and some studies have already begun to implement it. There is.

FIG. 1 is a system diagram showing an example of sensible heat recovery equipment for explaining the present invention.
Crude COG is taken out through each branch pipe 2, collected in a conduit 3, and then sent to a heat recovery device 4. The heat-recovered crude COG is adjusted to a predetermined temperature, and then sent to a gas purification facility 10 through a return pipe 5. Sent.

In such sensible heat recovery equipment, since the conduit 3 expands and contracts due to the high temperature gas, an expansion joint 6 using a bellows is provided in the conduit to adjust this. In addition, since each coke oven is operated in batch mode, a gas cutoff valve 7 is installed at the crude COG outlet of each coke oven, and
Each gas cutoff valve 7 is opened and closed depending on the generation status of COG, and crude COG is taken out intermittently. Therefore, crude COG from the coke oven with the gas cutoff valve 7 open is constantly flowing through the conduit 3. In addition, 8 is a hot air pipe, 9a is a damper valve, 9b is a dry main,
32 is a hot air generating section.

By the way, crude COG contains large amounts of high-boiling substances such as benzenes and tar, as well as water and other soluble impurities. 6 and the shutoff valve 7, and solidify over time, causing a so-called coking phenomenon. This coking phenomenon becomes more pronounced as the piping conditions change (for example, changes in bending or pipe diameter), the roughness of the gas contact surface, and the temperature difference between the inner and outer surfaces increase. Therefore, a caulking phenomenon may occur inside the expansion joint 6, and the bellows may become unable to expand or contract.

On the other hand, if the conventional water seal damper valve is used as the gas cutoff valve 7, the
The COG is cooled by the seal water and caulking deposits near the water seal, making it difficult to shut off the crude COG. Furthermore, when a normal gate valve or spherical valve is used, caulking adheres to the vicinity of the seal and the valve stem, which not only makes operation difficult, but also makes it impossible to shut off the coarse COG.

In order to remove the coking deposited on the expansion joints 6 and the gas cutoff valves 7, the cutoff valves 7 of each coke oven 1 are closed to interrupt the extraction of crude COG, and the conduits 3 and the cutoff valves 7 are closed. Hot air (500℃) is applied to the valve box.
de-coking, which cleans the interior by burning the caulking material at temperatures up to 1,000°C), but even with this method, the caulking material deposited near the seal between the valve body and valve seat, and the valve It was difficult to completely remove the caulking that had adhered to the rods, and valves were still difficult to open and close, and gas leaks continued to occur. Although most of the coking material adhering to the valve stem can be removed by decoking, crude COG can be extracted intermittently by opening the shutoff valve of a particular coke oven among the many coke ovens operating in batches. Therefore, even if the coking material on the valve stem is removed by de-coking, there is still crude COG from other coke ovens inside the valve box.
is constantly flowing, which causes caulking to adhere to the valve stem again, making it difficult to move the valve stem up and down.

This invention was developed to solve the above-mentioned problems, and in addition to decoking with hot air, the valve itself is operated from the outside to slide the valve seat and valve body together to create a seal. complete,
A further object of the present invention is to provide a crude coke gas cutoff valve for a coke oven that automatically removes coking substances adhering to the valve stem.

In order to achieve the above object, the present invention is equipped with a passage having a valve seat and connected to a coke oven, an inlet for hot air, and an outlet for crude coke gas, and the upper part is closed with a cover plate. It consists of a valve body and a valve stem, which has a valve body attached to its tip to be adhered to the valve seat, and which is attached to a guide attached to the cover plate of the valve body so as to be able to move up and down and rotate. The present invention provides a coarse coke gas cutoff valve for a coke oven, characterized in that the valve body and the sealing portion of the valve seat are slid together by being adhered to the seat and rotated. The present invention will be explained below using the drawings.

FIG. 2 is a longitudinal sectional view of an embodiment of the present invention. In the figure, 10 is a cylindrical valve box, and a valve seat 12 is provided in a passage 11 connected to a branch pipe 2 from a coke oven 1.
It is equipped with an inlet 13 of hot air for decoking and an outlet 14 for crude COG connected to the conduit 3.
The upper part is closed by a cover plate 15. 20 is a valve stem, and 21 is a valve body semi-fixed to the tip of the valve stem 20. Reference numeral 22 denotes a guide for the valve stem 20 that is inserted and fixed into a hole provided in the center of the cover plate 15. The valve stem 20 is inserted through the hole so that it can move and rotate in the vertical direction. A contacting edge portion 24 is formed. Reference numeral 25 designates a rotation mechanism mounting portion, and in this embodiment, a portion of the valve stem 20 is formed into a polygonal shape.
26 is a connecting member, and a bearing 27 is interposed between it and the upper end of the valve stem 20, and this connecting member 2
A driving member 28 that contacts the upper end of the valve stem 20 and the bearing 27 is fixed to the valve 6 . Reference numeral 30 denotes a lever whose one end is pivoted to a fixed part 40, whose center part is pivoted to a drive member 28, and whose other end is provided with a counterweight 31 whose weight can be adjusted.

In the gas cutoff valve configured as described above, in the state shown in the figure, the valve stem 20 is lowered by the counterweight 31 with the weight of the lever 30 adjusted, and the valve body 21 and the valve seat 12 are brought into close contact to form a passage from the coke oven. This prevents crude COG from flowing out. Therefore, in this state, if hot air is sent from the inlet 13, the hot air passes through the inside of the valve box 10 and flows from the outlet 13 to the conduit 3, causing the valve body 10, the valve stem 20, the conduit 3, the expansion joint 6, etc. Clean by burning the caulking deposits. This decoking may be performed for each coke oven, or for multiple coke ovens at the same time.

Next, when the valve (not shown) provided in the return pipe 5 is closed and the counterweight of the lever 30 is pulled up,
Since the valve stem 20 moves upward and the space between the valve body 21 and the valve seat 12 is opened, the crude COG inside the coke oven is
is delivered from the valve body 10 to the conduit 3 via the outlet 14.

By the way, even if decoking is performed using hot air as described above, caulking material still adheres to the valve stem 20 as described above, and the vicinity of the sealing part between the valve body 21 and the valve seat 12 remains. There is caulking deposited on the surface. In the present invention, the valve body 21 on which the caulking material has been deposited is
The seal on the valve seat 12 and the caulking material adhering to the valve stem 20 are removed as follows.

(1) Seal between valve body 21 and valve seat 12 When the valve stem 20 is lowered by the lever 30, the seal portion of the valve body 21 comes into contact with the seal portion of the valve seat 12 and stops. At this time, since caulking has been deposited on the surfaces of the seal portions of the valve body 21 and the valve seat 12, they do not come into direct contact with each other, and the caulking is present between them. Therefore, the exhaust gas inside the coke oven leaks from between the valve body 21 and the valve seat 12, and cannot be completely shut off.

Therefore, the weight of counterweight 31 is 0 to 50.
The contact pressure between the valve body 21 and the valve seat 12 is set to 0.3 to 0.8 Kg/cm ² (contact line length) by adjusting as appropriate within the range of Kg. Next, the rotation mechanism mounting portion 25 provided on the valve stem 20
For example, if a wrench is fitted to rotate the valve stem 20 from side to side, the valve body 21 semi-fixed to the valve stem 20 will also rotate, and the seal portion between the valve body 21 and the valve seat 12 will automatically slide together. This allows for a complete seal between the two. In this case, even if there is a small amount of gas leakage, the gap between the two will be completely sealed due to the self-sealing action of the high boiling point sticky substance such as tar in the crude COG.

(2) Removal of caulking substances adhering to the valve stem 20 When the valve stem 20 is moved up and down by the lever 30, the caulking substances adhering to the valve stem 20 are completely removed by the edge provided at the tip of the guide 22. .

FIG. 3 is a front view showing the main parts of another embodiment of the present invention. In this embodiment, a reversible motor 41 is attached to the cover plate 15, a sprocket 25a is attached to the valve stem 20, and a small sprocket 42 and a chain 43 are driven by the output of the motor 41.
In addition, a hydraulic cylinder 45 is attached to the cover plate 15, and a connection between the operating rod and the driving member 28 is made.
The intermediate portion is connected by a lever 46 that is pivoted to a fixed portion. With this configuration, the vertical movement and rotation of the valve stem 20 can be performed automatically without manual effort. In this case, the valve body 2
The sliding pressure between the seal portion of the valve seat 1 and the valve seat 12 can be arbitrarily adjusted by the position of the operating rod of the hydraulic cylinder 45 or the hydraulic oil pressure. Note that the mechanism for rotating the valve stem 20 by the output of the motor 41 is not limited to the sprocket and chain, and a gear mechanism or other transmission mechanism may be used.
Although a case has been shown in which the lever 46 connected to the lever 46 is driven by the hydraulic cylinder 45, an air cylinder, a motor, etc. may also be used.

Although the configuration and operation of the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, but includes various modifications without departing from the gist thereof.

As is clear from the above explanation, the gas cutoff valve according to the present invention includes (1) an inlet for hot air for decoking provided in the valve box;

(2) To ensure a perfect seal between the valve body and valve seat, the valve body can be rotated to allow the seal parts to slide together.

(3) An edge was provided on the valve stem guide to remove caulking that adhered to the valve stem.

This is characterized by the following remarkable effects.

(1) By introducing hot air from the inlet to de-coak the valve body, valve stem, and other equipment, the sealing performance between the valve seat and the valve body can be greatly improved.

(2) When starting a coke oven plant,
Equipment that COG comes into contact with must be preheated (400 to 600
°C), the deposition of caulking material is significantly reduced. Therefore, hot air for preheating can be introduced from the inlet to preheat various equipment, thereby reducing the deposition of caulking materials.

(3) Even if there is gas leakage due to the seal between the valve body and valve seat not coming into close contact, the seal can be brought together by external operation, so there is no need to stop the operation of related equipment for repairs. .

(4) The contact pressure and sliding pressure between the valve body and valve seat can be adjusted as desired by adjusting the counterweight, hydraulic cylinder, etc.

(5) Caulking material adhering to the valve stem can be removed by external operation using the edge provided on the guide, which not only allows smooth opening and closing of the valve, but also significantly reduces damage to the guide.

(6) The above (2) to (5) enable the de-coking cycle to be extended.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of an example of sensible heat recovery equipment for explaining the present invention, Fig. 2 is a longitudinal sectional view of an embodiment of the present invention, and Fig. 3 is a front view of the main parts of another embodiment of the present invention. It is a diagram. 1: Coke oven, 2: Branch pipe, 3: Conduit, 5: Return pipe, 10: Valve box, 12: Valve seat, 13: Hot air inlet, 14: Crude COG outlet, 15: Cover plate, 2
0: Valve stem, 21: Valve body, 22: Valve stem guide, 2
4: Edge portion, 25: Rotating mechanism mounting portion, 28: Drive member, 30: Lever, 31: Counterweight, 41: Motor, 45: Hydraulic cylinder.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A crude coke gas cutoff valve used in equipment for recovering sensible heat of crude coke gas generated in a coke oven, which has a valve seat and a passage connected to the coke oven. ,
a valve box having a hot air inlet and a crude coke gas outlet, the upper part of which is closed with a lid plate; The valve stem is mounted on a guide so as to be movable up and down and rotatable, and the valve body is adhered to the valve seat and rotated so that the seal portion of the valve body and the valve seat slide together. A crude coke gas cutoff valve for a coke oven, characterized by: (2) The coarse coke gas cutoff valve for a coke oven according to claim 1, wherein a guide attached to the lid plate of the valve box is provided with an edge portion that slides into contact with the circumferential surface of the valve stem. (3) The crude coke gas cutoff valve for a coke oven according to claim 1, wherein the valve stem is moved up and down. (4) The crude coke gas cutoff valve for a coke oven according to claim 1, wherein the valve stem is rotated by the output of a motor.