JPS5945032B2 - Sensible heat recovery equipment for coke oven gas - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for recovering sensible heat contained in gas generated in a coke oven.

Conventionally, the gas generated in a coke oven was cooled by blowing cooling water into it, and then the gas was used as a fuel or a chemical raw material.

Therefore, a large amount of sensible heat contained in this gas is not recovered and is discarded together with the cooling water.

This is because coke oven gas contains a large amount of tar, and when a heat exchanger is inserted into the gas flow path to recover the sensible heat, tar adheres to the surface of the heat exchanger. The reason why sensible heat has not been recovered in conventional systems is that this can lead to breakdowns or deteriorate heat exchange efficiency, making it unprofitable.

FIG. 1 shows an example of the conventional device. In FIG. 1, 2 is a cooling chamber, and coke oven gas having a temperature of T is introduced into the cooling chamber 2 through a pipe 1, and a cooling water pipe 6 The tar is removed from the gas by the cooling water jetted out from the gas, and the tar is discharged from the discharge lower to the outside of the cooling chamber 2 together with water.

The gas, which has been cooled to a temperature of T2 and from which tar has been removed, is sent from the pipe 3 to the storage tank 4, and is used via the pipe 5.

As described above, in the conventional example, the sensible heat of the coke oven gas was not recovered, but was discharged together with the cooling water.

This is regrettable from the point of view of energy conservation.

The object of the present invention is to provide an apparatus that effectively recovers the sensible heat of coke oven gas that was wastefully discharged in the conventional example. Before being sent to the cooling chamber, the gas is sent to a heat recovery device that has a heat transfer tube for heat recovery, where the sensible heat of the gas is recovered and the heat transfer tubes of this heat recovery device are treated to prevent tar from adhering to the gas. In order to prevent this, a device is further provided to remove tar from the coke oven gas, and when tar adheres to the heat exchanger tubes, a means is provided to remove it by dissolving it with a solvent. It is characterized by the following points.

Next, the present invention will be explained in detail with reference to the drawings from FIG. 2 onwards.

In this embodiment, the members indicated by reference numerals 1 to 7 are the same as those in FIG. 1, so a detailed explanation thereof will be omitted.

Reference numeral 32 designates a cylindrical main body of the tar removal device which is constituted by a double pipe consisting of an inner surface 32'' and an outer surface 32', and water to be heated (supplied water) is supplied to the space 32'' between the inner and outer surfaces.

Reference numeral 31 denotes a coke oven gas guide (inlet) provided at the lower end of the main body 32, gas is supplied into the main body 32 from the komata, and the lower end of the shaft 39 is pivotally attached to a support fitting 38 provided at the komata. There is.

A gear 15 is fixed to the upper end of the shaft 39.
5 meshes with a pinion 17 driven by a motor 16.

A knife 12 that is in sliding contact with the inner surface of the main body 32 is mounted on the shaft 39 with a plurality of connecting fittings 13, and a plurality of rotating blades 1 are mounted on the shaft 39.
0 is attached.

An annular tar reservoir 33 made of a heat insulating material is attached to the inside of the lower end of the main body 32, and a tar extraction pipe 36 is connected to the annular tar reservoir 33 made of a heat insulating material.
is installed.

A heat recovery device 18 is attached to the upper surface of the main body 32, and a heat exchanger tube 19 is inserted inside the heat recovery device 18.

20 is a header of the heat exchanger tube 19. An upper shut-off device 22 and a lower shut-off device 21 are provided at the upper and lower sides of the heat recovery device 18, respectively, and a cleaning liquid supply pipe 24 and a cleaning liquid discharge pipe 23 are opened between the two devices. do.

26 is a cleaning liquid tank, and 25 is a pump.

While supplying water into the space 32'' of the main body 32,
Coke oven gas is supplied from the lower guide 2, and the shaft 39 is further rotated.

The gas supplied into the main body 32 rises within the main body 32 while being swirled by the swirl vanes 10 .

As a result of this swirling, the tar contained in the gas is separated by centrifugal force and scattered onto the inner surface 32'' of the main body 32, where it is cooled and attached.

If this tar is liquid, it flows down along the inner surface 32'' and accumulates in the tar reservoir 33 as molten tar 35.

If it is solid, it is scraped off by the knife 12 sliding along the inner surface 32'', falls into the molten tar 35 in the tar sump 33, is melted by the molten tar 35, becomes liquid, and is transferred to the tar extraction tube. 36 to the outside.

If this tar is in a gaseous (vapor) state, it cools and liquefies when it comes into contact with the main body 32 and flows down.

On the other hand, as the coke oven gas rises while swirling inside the main body 32, it imparts heat to the water supply in the main body 32 and is cooled.

The gas then flows into the heat recovery device 18 provided at the upper end of the main body 32 and is further cooled by contacting the heat transfer tube 19 provided there, but at this time most of the tar content has been removed from the gas. Therefore, not much tar adheres to the heat exchanger tubes 19.

Therefore, the heat transfer efficiency of the heat exchanger tubes 19 is extremely good and efficient (the sensible heat of the gas is recovered by the fluid inside the heat exchanger tubes 19).

When tar adheres to the surface of the heat transfer tube 19, the inside of the heat recovery device 18 is sealed by the upper and lower shut-off devices 22 and 21 (the shut-off devices 22 and 21 are left open during normal operation). ) In this closed space, pump 2
5, the cleaning liquid 21 is circulated and supplied from the tank 26, and the tar on the surface of the heat exchanger tube 19 is dissolved in the cleaning liquid.
90 Freshen the surface.

Note that it is also possible to clean the inside of the main body 32 with the cleaning liquid.

In this way, the gas from which most of the tar has been removed and which has released sensible heat is further subjected to the final tar removal and cooling by the cooling water 6 in the cooling chamber 2, and is stored in the tank 4.

As described above, the sensible heat of the gas is recovered by heating the water supply in the internal space of the main body 32 and the water supply in the heat transfer tubes 19 to turn them into steam.

In particular, inside the main body 32, the inner surface 32'' of the main body 32 is heated by strong convection due to gas swirling and radiation due to high temperature, and a large amount of heat is imparted to the water supply of the main body 32.

Note that since the swirl vanes 10, shaft 39, and support device 38 do not directly cool the gas, they have the same temperature as the gas, and almost no tar adheres to them.

In this device, the knife 12 may be supported at the tip of the swirling vane 10, and the connecting fitting 13 may be shaped like a swirling vane.

Thus, according to the present invention, the sensible heat of the coke oven gas is recovered by the heat recovery device, but most of the tar contained in the gas is removed before the gas is introduced into the heat recovery device. Since the tar is removed, almost no tar adheres to the heat exchanger tubes of the heat recovery device.

Further, even if it adheres, it will be dissolved by the cleaning solution, leaving the heat transfer tube fresh and improving its heat transfer efficiency.

On the other hand, the water supply for sensible heat recovery is also supplied to the main body constituting the tar removal device, and in order to recover the sensible heat of the gas even in this case, in accordance with the present invention, the coke oven gas Sensible heat is very effectively recovered and used in the form of steam, so the sensible heat of the gas is effectively used, which is very desirable from the point of view of energy saving.

Note that it is clear that the main body 32 may be constructed by tightly winding a pipe as shown in FIG. 4.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional example, FIG. 2 is an explanatory diagram of an embodiment of the present invention, FIG. 3 is an enlarged view of the main part, and FIG. 4 is another embodiment of the same main body. 1.--- Gas supply pipe, 2... Cooling chamber, 4.
... Tank, 6 ... Cooling water pipe, 7 ...
...Discharge pipe, 10...Swirl vane, 12...
・Knife, 13...Connecting fittings, 15...
・Gear, 16... Motor, 17... Pinion, 18... Heat recovery device, 19...
・Heat transfer tube, 21° 22... Closing device, 23.
...Washing liquid supply pipe, 24...Same discharge pipe,
25...Pump, 26...Tank, 3
1...Guide, 32...Main body of the tar removal device, 33...Tar reservoir.

Claims (1)

[Claims] 1 The main body of the tar removal device is constituted by a cylindrical double inner and outer surface, water is supplied to the space between the two surfaces of the main body, and a shaft driven by a motor is mounted inside the main body, A swirl vane and a knife that slides along the inner wall of the main body are fixed to the shaft, a tar reservoir made of a heat insulating material is provided at the lower end of the inner surface of the main body, and a heat recovery device is installed at the upper end of the main body. A heat transfer tube is inserted into the heat recovery device, a shutoff device is provided at both the upper and lower positions of the heat transfer tube, and the cleaning liquid from a separate cleaning liquid tank is poured into the space divided by both shutoff devices. A coke oven gas sensible heat recovery device equipped with a pump and piping for circulation.