JPS59161482A - Pretreatment of coal for coke furnace and unit therefor - Google Patents

Abstract

PURPOSE:The high-temperature coke furnace gas is brought into direct contact with the starting coal to effect preheating for drying and condensation of tar components on the surface of the coal, then the coal is compacted, whereby the treatment of starting coal for coke furnaces is conducted economically with high safety. CONSTITUTION:The high-temperature coke furnace gas from the coke furnace 1 is introduced into the by-pass line 7, sent into the drier I to come into direct contact with the starting coal, as they are allowed to flow in parallel. During the direct contact of the coke furnace gas with the coal, the wet starting coal is preheated for drying and simultaneously the tar is made to deposited on the coal surface, then the resulting coal is compacted in the compaction unit.

Description

[Detailed Description of the Invention] In history, coking coal (wet coal) is pre-dry-smoked using gas in a cooperating oven to precipitate tar onto the surface of the raw coal (j≦1), and this tar deposits. Coke oven coking coal processing method for consolidating coking coal and -! This relates to A16.

Conventionally, the treatment of coking coal to be charged into a coke oven has been limited to drying of coking coal to be charged to a coke oven to a moisture content of around 6% without the generation of dust, etc. , ■Preheated coal charging methods such as precarbon method and coal tick method.

However, in the method of ■, IiI11 until after the moisture content is 6%
Since it is limited to humidity, there is still room for improvement in various effects such as increasing bulk density and shortening carbonization time. In particular, the cause of the increase in bulk density is the fine powder of 100 mesh or less, There is a drawback that in order to separate this, it is necessary to dry it to less than 6%.

Method (2), which is currently being implemented in some areas, uses coke oven gas as a heat source. In addition, tar addition equipment is installed separately in the preheated coal recovery process, and it is necessary to keep the tar warm, which not only makes the equipment expensive, but also requires a coke oven] The drawback is that the energy saving effect for the entire field is small.

Furthermore, conventionally, the technology of recovering the retained heat of coke oven gas and using it for coal wetting has been known (Japanese Patent Laid-Open No. 57-10
No. 0184, No. 57-100185). However, with this technology, the recovery of heat from coke oven gas is limited to a degree where tar does not condense, so approximately 50% of the heat retained in coke oven gas is not recovered and used. The energy saving effect is small and there is room for further improvement. In addition, heat transfer is indirect in the process of heat recovery and heat utilization for drying, and there is also heat loss in the circulation system of the heat medium, which inevitably reduces heat recovery efficiency. A mold dryer has the disadvantage that it is difficult to uniformly dry the raw coal in a way that corresponds to the particle size of the coking coal.

The present invention improves the recovery efficiency of heat retained in coke oven scum to the temperature range where tar condenses, and J! In addition to being used for drying and preheating of RJ coal, it is also used to strengthen the drying of raw material l# when using a hand cylinder, as dust-proofing and explosion-proofing measures during charging, carryover measures during coal carbonization, as well as compaction and compaction cake during molding. The strength of the charcoal is improved by adding tar as a caking agent, and furthermore, this tar addition is made possible by drying and preheating one culm as described above, thereby solving the drawbacks of the conventional method and adding tar. The coking coal is compacted, shaped into a cake, and charged into a coke oven.It simultaneously recovers the retained heat of the high-temperature coke oven gas discharged from the coke oven, preheats the coking coal for drying, and adds tar. The process of coking coal is known as consolidation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the structure of the embodiment, where l is a coke oven;
2 is the upper Y1 pipe, 3 is the dry main, 4 is the damper, 5 is the ammonium water spray nozzle, 371 is the carbonization ((and the carbonization chamber 37
The coke oven scum that has passed through the riser pipe 2 is transferred to the dry main 3.
The spray tension of the ammonium water spray nozzle 5 is adjusted to maintain the coke oven gas at a predetermined temperature.

This 1) installation 01B uses the existing installation (6Fi).

The characteristics of the present invention are as follows. A bypass line 7 is connected to the suction main 6 leading to the plant, and the bypass line 7 is provided with a dryer 1 that dries the coking coal using the heat retained in the coke oven dregs as a heat source. A gas-liquid shunting device 8 using an ammonium water spray nozzle 5 is installed as the main part to cool the coke oven scum leaving the dryer 1, and capture residual tar and powder in the gas in the ammonium water for gas-liquid separation. To the history, dry ml
The compacting device 1 is provided between the coke oven 1 and the coke oven 1.

The dryer 1 is installed in the bypass line 7 because the dryer 1 is installed in the bypass line 7.
This is for rubbing without interfering with the coke oven ψ operation when the 411+ is shut down. 9 and 10 are valves. The coke oven scum byproduct processing equipment can employ one existing 9-valent unit. However, when the coke oven scum passes through the dryer 1,
It is necessary to increase the capacity (wind pressure) of the JF departure.

Next, in the present invention, the dryer 411 is installed and used as described above.
The structure shown in FIG. 3 is used. That is, first, a parallel flow method is suitable for the method of contacting the coke oven gas and the coking coal. Methods of contact between coke oven gas and coking coal include a countercurrent method, a cross method method, and a cocurrent method.In the countercurrent method, the raw material is Tar adheres to the coal, but the target is not achieved because the tar evaporates from the surface of the coking coal due to countercurrent contact with the high temperature coke oven gas at the dryer outlet side. Tar adheres to the surface of the coking coal (on the side where the gas temperature is low), but since the movement of the coking coal intersects with the cooling of the gas, the coking coal of the gas worker c1flll (on the fil+ side with a high gas temperature) has tar condensation. It is not f good because υ is given out without clothes. In this respect, in the parallel flow equation,
This is preferable because tar uniformly adheres to the stored coal that comes into contact with the coke oven gas and is discharged from the JJF at the exit side of the gas and coking coal (where the degree of scum deviation is low).

In particular, the type of dryer 1 is as follows: (a) Coking coal contains a large amount of moisture around the fine grains (particularly less than 100 mesh) to form pseudo particles.

Therefore, in order to uniformly dry particles regardless of particle size, a cooling bed or an airflow bed that can disperse particles in an airflow is more effective than a packed bed or a moving bed.

(b) Drying by passing gas through a packed bed or moving bed made up of fine coking coal containing moisture is not a good idea as it has high ventilation resistance and tends to cause uneven gas flow, and tar can adhere to the coking coal. There are further problems in this case. Therefore, if the raw coal is not to be fluidized, it is preferable to aerate the surface of the raw coal while stirring and mixing.

In consideration of the above, in the present invention, as the most suitable dryers, a direct heating multi-stage disk type dryer shown in FIG. 2 and a flash drying type shown in FIG. 3 are adopted.

The a-heated multi-stage disk type dryer 1 shown in FIG. Circles #13 and #14 are installed in multiple stages. The disks 14 have holes in the center that serve as gas passages, and are arranged alternately with the disks 13. Furthermore, a fixed rake (not shown) extends from the casing 11 above each disc 13, 14 for stirring the coking coal.

Reference numeral 38 denotes a cone-shaped partition fixed to the casing 11, and a sealing device (not shown) is provided at the portion in contact with the disk 14. The disk 13 is rotated by rotating the rotating shaft 12.
．． 14 is rotated to supply the coking coal in one coking coal supply hopper 15 via the rotary valve 16 to the disc of the silent stage], and also to allow coke oven gas to flow in from the coke oven scum supply duct 17. 11. Do not bring the coking coal chamber into direct contact with the coke oven gas and stir the coking coal.
By inverting the coal and dropping it onto the disk of the F-stage, the coal is dried uniformly, tar is evenly attached to the raw coal, and the raw coal is discharged from the raw coal jJF outlet passage 18. on the other hand,
The gas used for drying the coking coal is transferred from jJF output tact 19 to H.
It is designed to make E come out.

In addition, the smoke-type dryer 1 shown in FIG. 16! coking coal is fed into the flash drying tower 20 from the rotary valve 24, and coke oven scum is blown into the flash drying tower 20 from the coke oven gas supply duct 22. The coking coal and coke oven gas flow upward in parallel, drying the coking coal and uniformly depositing condensed tar on each piece of coal. The raw coal is separated into waste and raw coal, and the raw coal is taken out from the rotary tr27.

In the above-mentioned dryer, in the figure, solid arrows indicate the flow of coke oven dregs, and white arrows indicate the flow of coking coal.

Since the -J apparatus of the present invention has the above-mentioned configuration, the high temperature coke oven gas discharged from the coke oven l or e>J# is guided to the vice line 7, flows into the dryer W411+, and is supplied to the dryer 4j11. Co-current flow is carried out while directly contacting the coking coal. In this case, the coke oven gas introduced into the dryer 1 is at a high temperature of about 800"C, the coking coal is KA coal with a -3 ratio of about 85% and a moisture content of about 9.5%, and the coke oven gas is dried. While the coke oven dregs are brought into direct contact with iμ and transported through the dryer 1, the heat retained in the coke oven dregs is recovered to dry and preheat the wet coal, and condensed tar is attached to the surface of the coking coal. This prevents the generation of dust in the subsequent process, and furthermore, it is used effectively as a caking agent (the pitch contained in tar is particularly effective). Remaining tar and powder are removed by spraying with ammonium water.

The relationship between the water content (%) in the coking coal (wet coal) and the coke oven gas cooling temperature caused by the contact between the coking coal (wet coal) and the coke oven gas in the dryer is shown in FIG. Figure 4 shows the dryer temperature of coke oven scum at 800″C1
When the coking coal at the dryer entrance is 9.5%, coke oven scum and 1! ;-tl coal analytical relationship 0.32 ”
”/), g coa l (dry) and 1 l. Figure 5 shows the cooling rate of coke oven gas at the dryer outlet (11.l! degrees and tar). ii5 shows the relationship of reduction ratio (cumulative).

As is clear from Figures 4 and 5 of 1:8 pi, tar 3~
According to a trial calculation when coking coal containing 4% is used, if the coke oven scum cooling temperature is increased from 400"C to 370°C, the tar/J3 that shrinks 4 during the drying process will decrease from 1% to 10%.
However, most of the tar condenses between 350°C and 400°C, so drying of the wet coal does not progress much, and the moisture content remains at around 4%.

However, in reality, the amount of tar that adheres to the coking coal is a part of the amount of tar that has condensed to that temperature (the rest adheres to the wall or is discharged outside the machine). In order to condense the important amount of tar, it is necessary to further lower the cooling temperature of the coke oven gas and increase the amount of tar condensed. Adhesion of tar to coking coal) V varies depending on the purpose. For example (f), in order to prevent dust generation from dry coal, the tar adhesion rate should be around 1%, 11 When using fLJ as a binding material binder, it is necessary to increase the amount of adhesion to about 6 to 10%.On the other hand, when it adheres to liquid tar or coking coal, its retained heat causes it to bind in the wet coal. evaporates.Therefore, the moisture content of the coking coal is actually much lower than 4%, which can fully achieve the purpose of dehumidification.Therefore, the characteristics of the dryer can be emphasized and the required tar coagulation can be achieved. By adjusting the cooling temperature of coke oven gas at the outlet of the dryer so as to obtain a
It is possible to expand the use of low-rank coal as coking coal for coal.

The drying of coking coal has been described above, and the present invention is characterized in that 1KF coal on which tar has adhered through the drying process described above is subsequently subjected to consolidation treatment to increase its added value (llj). That is, a coking coal compaction device 0 is installed after the dryer 1 (see Fig. 1), and after the necessary tar has adhered to the coking coal surface, it is compacted by the compaction device. Fig. 6 shows an example of the above-mentioned compaction device U, and K
A hopper 29 is installed in the downward direction j of the coal bunker 28, and a stamping box 3o is installed in the F side of the hopper 29, with a shield plate erected on a frame 31 and shield plates 32 and 33 after +n+ made movable. A stand 34 movable in the 117114 direction is provided above the stamp pink box 30, and the stamper 35 is attached to the pack 1i34.
The stamper 35 stamps (consolidates) the raw coal dropped into the stamping box 30 while moving, and when it is consolidated in the stamping box 30, the shield plate 32 of 691 is moved. After that, the rear shield plate 33 is moved forward together with the movable bottom plate 36, and the 11° dense cake-shaped raw coal on the movable bottom plate 36 is inserted into the coking chamber 37 of the coke oven. In the case of molded coal, a double roll molding machine may be used.

Since the present invention has the structural functions as described below, it can produce the following excellent effects.

(1) Recovery of retained heat of coke oven gas and + of coking coal
22 Since drying preheating and tar addition can be carried out almost simultaneously in the 1st step, equipment costs are reduced.

(j) Since the heat retained in the coke oven gas can be recovered up to the temperature range where the tar content condenses, the energy saving effect is large and the average fuel consumption can be reduced.

OiD Tar adheres to the surface of the coking coal, which serves as a dustproof and explosion-proof measure during handling and charging of the coking coal, and as a carryover countermeasure during coal carbonization. ) can be achieved.

(ivl YA'tH tar added to coking coal is essentially only circulated between the dryer and coke oven, and the tar is not consumed, but the tar inherent in coking coal becomes a by-product as before. will be collected as.

(V) The device of the present invention does not require major equipment modification when installed in an existing indoor coke oven.

(ui) The raw coal for consolidation and molding can be dried and preheated, and tar can be added as a caking agent, so the strength of the 11-rich cake and molded coal can be increased (if the moisture content is 8% or more, the cold hardening of the compacted cake) [Caking agent is required because the strength becomes weak and it becomes impossible to insert the cake into the coke oven] and the use of inexpensive substitute coal can be expanded by increasing coke strength by improving softening and melting properties. Therefore, raw material costs can be reduced, and a separate tar addition device can be used, so the installation af.
can also be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, FIG. 2 and FIG.
The figure is an explanatory diagram of the pre-dryer in the apparatus of the present invention, Figure 4 is a diagram showing the relationship between coke oven gas cooling temperature and coking coal moisture, and Figure 5 is a diagram showing the relationship between coke oven gas cooling degree and tar condensation. FIG. 6, which is a diagram showing the relationship with the ratio, is an example of a compaction device employed in the present invention. 1... Drying machine, 1... Coke oven, 6... Suction main, 7... Bypass line, 11... Casing, 13.14... Disc, 2o... Flash drying tower. #8 Permission Application Person 1 Kawashima Torima Seki Kogyo Co., Ltd.'4. V-revised applicant's agent Figure 3 Figure 6

Claims (2)

[Claims] (1) The high-temperature coke oven gas discharged from the coke oven is brought into direct contact with the coking coal, during which time the coking coal is dried and preheated using the heat retained in the coke oven dregs, and the tar is adhered to the surface of the coking coal. , a method for processing coke oven coking coal, characterized by consolidating the coking coal. (2) A dryer is connected to the high-temperature coke oven gas recovery line coming out of the coke oven, which brings the coke oven gas and coking coal into direct contact and dries the coking coal using the heat retained in the coke oven gas as a heat source. , and further jJl from the dryer.
A coke oven coking coal processing apparatus characterized in that a compaction device for compacting discharged coking coal is provided after a dryer.