JPH0629431B2 - Dry coke cooling method and dry coke chiller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dry coke cooling method as described in the preamble of claim 1 and an apparatus for carrying out the method as claimed in claim 3.

The dry coke cooling method has been a known method for decades,
Accordingly, the burning coke extruded from the coke oven is filled in the cooling cylinder, and the coke is cooled by the ascending inert gas in the cooling cylinder. Thus, such a tubular cooling device operates according to the principle of a movable fixed bed associated with the direct heat exchange of solids and gases in the countercurrent type. Until recently, an inert gas was exclusively used as the cooling gas. The hot inert gas leaving the coke cooler was usually used in a flue boiler to generate steam.

Until more recently, dry coke cooling and drying and preheating of coking coal was not done by direct heat exchange of coke and coking coal with the same circuit medium. This is because the steam generated by the dryer and the preheater during coke cooling causes an undesirably high burnout due to the aqueous reaction. A further disadvantage of all dry coke cooling methods is the high construction cost and / or poor heat transfer to the heat consumer side.

The problem of making it possible to transfer the sensible heat of the cooling gas directly to the heat consuming machine without burning out the coke to be cooled more significantly than in the case of the known dry coke cooling method is mentioned at the outset. It has been solved by a method according to the general idea of the above type and a suitable device (German Patent Publication No. 3203732). In this known cooling method, coke cooling takes place in both cooling stages of a cooling gas circuit which are separated from one another in countercurrent fashion with respect to the coke, in which case only the cooling gas of the second cooling stage contains steam. In contrast, an inert cooling gas was used as the cooling gas for the first cooling stage. This limited coke burnout to less than 1 weight percent. The cooling gas containing steam in the second cooling stage is used for preheat treatment of the coking coal performed by direct contact between the coking coal and the cooling gas, and is used as the cooling gas containing steam for coking. The steam produced during the preheating of the charcoal was used. In any case, this known cooling method presents the problem of separating the two cooling gas circuits, which then necessitates the incorporation of a coke sluice gate in the cooling vessel between the two cooling stages. In particular, it must be ensured that the inert cooling gas of the first cooling stage does not contain water vapor. Furthermore, the inert cooling gas of the first cooling stage must be cooled again after leaving the cooling vessel itself. This is only done by indirect heat exchange processes with a corresponding reduction in efficiency.

In another dry coke cooling method known from DE 2952065, a nearly complete recovery of the sensible heat of the caustic coke is achieved by countercurrent flow of an inert cooling gas in a single-stage cooling vessel. This is done by being guided over the entire height of the coke ballast and additionally by using a water-cooled jacket surface and built-in components in the cooling vessel.
This likewise successfully avoids coke burnout and reduces the dust components entrained in the circuit gas,
The disadvantage is that the heat of the inert gas cooling gas cannot be fully utilized. In other words, this known cooling method always works with inert gas and is in any case single-stage. The division of the heat transfer method into the direct transfer method and the indirect transfer method is determined by the structure of the cooling cylinder. The inert gas contains water vapor to prevent coke burnout by oxygen and / or water gas due to the circulating gas flowing through the top (most heated) layer (zone) of the coke ballast. Not at all. Due to this mandatory limitation, this known cooling method is not suitable for direct connection with a preheating device for coke coal. This is because the heated circulating gas is not used, for example, in a flotation machine, but is re-supplied to the dry coke cooler with the coke water taken in after the heat has been released.

The object of the present invention is to make it possible to directly connect the heat treatment step producing steam with the coke cooling gas circuit without significantly burning out the coke to be cooled than in the case of the known dry coke cooling method. At the same time, a particularly effective dry coke cooling can be performed with a particularly high efficiency without separating the cooling gas circuit.

As a technical solution to the problem, the invention proposes a method and device of the type mentioned at the outset having the features of claims 1 and 3.

According to the invention, the coke cooling is carried out in the first cooling stage largely by the heat radiation between the coke and the heat exchanger wall and slightly by the heat transfer between the coke and the heat exchanger wall. That is, in the first cooling stage, the coke cooling is only indirectly carried out, so that there is no direct cooling by means of the cooling gas introduced through the coke ballast in direct contact. This only requires a single cooling gas circuit, complex back cooling (heat utilization)
Can be dispensed with and a particularly effective steam generation can be obtained on the secondary side by means of the heat exchanger walls. In this case overall a nearly complete recovery of the sensible heat of the cauterizing coke is obtained.

An advantageous embodiment of the invention ensuring particularly effective cooling and back cooling of the circuit cooling gas in the second cooling stage is:
It is described in another claim.

The aforementioned method steps or components used according to the invention are not subject to special exceptions in terms of process procedure and size, shape, material selection and technical construction, and are therefore well known in the respective field of use. The selection criteria can be used without restriction.

Further advantages, features and details of the invention are apparent from the following description of exemplary embodiments based on the associated drawings. The drawings show a preferred embodiment of a dry coke cooling device and schematically show a dry coke cooling device according to the invention.

The invention will now be described with reference to the illustrated embodiment.

The cauterizing coke is charged into a cooling container (cooling cylinder) 1 having a preliminary chamber 10 placed in front at a temperature of approximately 1050 ° C to 1100 ° C. After leaving the prechamber 10 which causes only a slight temperature loss, the coke is the first of the cooling vessel 1.
Reaches the inside of the cooling zone (cooling stage) 1a of the coke, and in this cooling zone, the coke is 800 due to only heat radiation and heat conduction.
It is cooled to a temperature of 850C to 850C. For this purpose, a jacket cooling surface 8 and an internal built-in cooling surface 9 are used, which are loaded on the secondary side by the feed water which again leaves the first cooling stage as steam. A conical mounting member (shown in phantom in the drawing) with an upper pointed tip that is selectively provided under the hopper.
After passing through the coke sluice gate or the contraction section 7, the coke flows into the second cooling zone (cooling stage 1b) of the cooling container 1. In this second cooling zone, the coke is cooled as much as possible, preferably to a temperature of approximately 200 ° C.

The second cooling zone is preferably operated countercurrently with a hot gas containing steam at approximately 150 ° C. with a steam content of approximately 50 to 90% by volume from a known coking coal dryer and preheater. To be done.

This cooling gas flows into the cooling stage 1b immediately above the coke removing device 3 via the cooling gas supply device 5 on the lower side. The cooling gas flows out from the cooling stage 1b at a temperature of approximately 600 ° C. via the cooling gas discharge device 6 in the contraction area or at the center of the contraction height. This cooling gas flow is indicated by an arrow in the drawing. 850 out of the total temperature difference given
K to 900K are used, of which almost 200K
~ 250K, ie about 25% is first due to steam generation
And the remaining 75% is transferred to the cooling gas and is used for drying and preheating the coking coal.

1 kg of coke brings about 1674 kilojuules of enthalpy in the chill. 1423 Kg is technically used. 376 kilometers is almost
Used to generate 0.16 kg of steam (approximately 20 bar). 1047 Kg is used for the preheating and drying of coking coal, which then requires 544 Kg to 837 Kg / kg of coke and correspondingly 724 Kg to 837 Kg / kg of coke. Accordingly, a heat balance, which is compensated for losses, is obtained in the combined operation of dry coke cooling / two cooling zones and coke drying / coke preheating.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Rohde, Wolffgang, Federal Republic of Germany D-4300 Etssen 14 Echsten Kemperwajk 5 (56) References JP-A-58-145781 (JP, A) JP-A-56-98281 (JP) , A) Japanese Patent Publication No. Sho 48-33601 (JP, B1)

Claims (4)

[Claims] 1. A dry coke cooling method using a cooling gas, comprising: (a) guiding coke and cooling gas in countercurrent through a two-stage cooling container, and (b) a first cooling. C) in the stage where the coke is cooled to a temperature of approximately 800 ° C. and c) the cooling gas guided through the second cooling stage contains water vapor, d) coke in the first cooling stage Cooling is performed only by indirect heat exchange between the cooling medium and coke through the heat exchanger wall that is in direct contact with, and (e) Cooling is performed only by the cooling gas containing steam in the second cooling stage. A dry coke cooling method using a cooling gas. 2. A cooling system comprising a cooling gas discharged from a cooling vessel for preheating the coking coal by direct contact between the coking coal and the cooling gas and containing steam for a second cooling stage. The coke cooling method according to claim 1, wherein water vapor generated when the coking coal is preheated is used as the gas. 3. A) guiding coke and cooling gas in counterflow through a two-stage cooling vessel, and (b) cooling the coke to a temperature of approximately 800 ° C. in the first cooling stage, and C) the cooling gas guided through the second cooling stage contains water vapor, and d) the cooling in the first cooling stage with the cooling medium via the heat exchanger wall in direct contact with the coke. In a device for carrying out a dry coke cooling method using a cooling gas, which is carried out only by indirect heat exchange with coke, and (e) cooling in the second cooling stage is carried out only by a cooling gas containing steam. , The device having an upper coke supply device (2), a lower coke removal device (3), a lower cooling gas supply device (5), and a central cooling gas discharge device (6) 2 Cooling consists of a tiered cooling vessel (1) The gas discharge device (6) is arranged at the upper end of the second cooling stage of the cooling container (1) and the wall of the first cooling stage of the cooling container (1) above the cooling gas discharge device (6) is Device for carrying out a dry coke cooling process with cooling gas according to claim 1, characterized in that it is designed as a fluid-cooled heat exchanger wall in direct contact with the coke. 4. The device according to claim 3, wherein a coke sluice gate (7) is arranged in the cooling vessel (1) between the first cooling stage and the second cooling stage.