EP0250420B1 - Apparatus for the cooling of coke - Google Patents

Abstract

PCT No. PCT/EP86/00147 Sec. 371 Date Dec. 17, 1986 Sec. 102(e) Date Dec. 17, 1986 PCT Filed Mar. 15, 1986 PCT Pub. No. WO86/05507 PCT Pub. Date Sep. 25, 1986.A coke quenching car comprises an open coke receptacle having a sloping bottom wall inclined toward one side, closely spaced vertical internal walls, a vertical side wall opposite the one side and end walls. All of the walls are formed with cooling fluid passages. The vertical side wall includes a coke discharge opening closed by a swingable L-shaped flap having a leg portion with a cooling fluid passage and a foot portion underhanging the bottom wall in a closed position. The foot portion is provided with aperatures for draining quench water from the receptacle when the flap is swung into a drain position. A fluid cooled slidable cover for the receptacle is provided.

Description

The invention relates to a movable coke receptacle for the indirect and direct cooling of coke with cooling walls for indirect heat exchange and a coke discharge flap arranged on the side.

So far, two fundamentally different processes have been used to cool the red-hot coke: wet quenching and coke-dry cooling:

In coke dry cooling, of which various process proposals are known from Glückauf 114 (1978), pages 611/619, the sensible heat of the coke is dissipated by direct or indirect heat exchange and largely recovered. In such plants, the coke is usually discharged at a temperature between 150 ° C and 250 ° C. The direct heat exchange is carried out by circulating gas, from which its energy is usefully extracted by renewed heat exchange.

With indirect cooling only, long dwell times are required, so that large usable volumes are necessary to ensure sufficient cooling capacity.

Capital and operating costs for dry coke cooling plants are comparatively high.

Although these process proposals do not produce any remarkable gaseous emissions, considerable problems which have not yet been solved have been found in practical operation to the extent that the handling of the dry-cooled coke produces a great deal of dust.

In wet quenching according to the general state of the art, the coke is cooled by the evaporation of sprayed water. As a result of the thermal buoyancy, particulate emissions arise, which in modern extinguishing towers are in the order of 50 g / t coke, as well as gaseous emissions in the form of e.g. B. hydrogen sulfide and carbon oxide by chemical reactions between the hot coke and water. Such reactions lead to considerable pollutant emissions in the temperature range above 800 ° C.

DE-AS 12 53 669 discloses a device for cooling coke, in which the coke is pre-cooled in a first stage by indirect heat exchangers and further cooled in a second stage by spraying with water. This device is very expensive in terms of equipment. Furthermore, it cannot be integrated into an existing coking plant without changing the peripheral equipment.

GB-A-20 36 674 describes a movable coke cooling device which is open at the top and in which the walls are designed as indirect water coolers. This measure reduces the corrosion caused by fire water.

GB-A-363 366 proposes a movable, closed device for dry coke cooling in which all walls are designed as indirect water coolers. Wet extinguishing of the coke in this device is not provided. The heat of the coke is mainly dissipated by dry coke cooling.

The object of the present invention is to overcome these disadvantages of the known coke cooling processes. In the device for cooling coke according to the invention, they are reliably avoided by the combination of features set out in the claim.

The dust problems that occur in coke-drying cooling systems do not occur in the procedure according to the invention, since the coke pre-cooled in the first stage is moistened uniformly when sprayed with water in the second stage, and dust formation during handling of the coke is thus prevented. At the same time, the coke temperature before wet quenching is reduced to such an extent that the reactions which occur more rapidly at higher temperatures are largely suppressed in the process according to the invention. In addition, the thermal buoyancy in the wet quenching stage is reduced, so that the particulate emissions are also considerably reduced.

The effort required is lower compared to coke dry cooling. As with coke dry cooling, however, part of the sensible heat of the coke can be recovered, the use of which further increases the economy.

• In Fig. 1 ist ein Verfahrensgrundschema abgebildet.
• Fig. 2 zeigt ein Ausführungsbeispiel des Koksaufnahmebehälters in Draufsicht,
• Fig. 3 den Gegenstand der Fig. 2 im Querschnitt,
• Fig. 4 eine Abwandlung des in Fig. 1 dargestellten Verfahrensschemas.

The device according to the invention is described in more detail using the example below.

• 1 shows a basic process diagram.
• 2 shows an embodiment of the coke receptacle in plan view,
• 3 shows the object of FIG. 2 in cross section,
• Fig. 4 shows a modification of the process scheme shown in Fig. 1.

In the embodiment shown in FIGS. 1 to 3, the coke is at a temperature of z. B. 1100 ^o e pressed out of the chamber 2 into one of the two coke receptacles 3, 3a. The coke receptacles 3, 3a are moved parallel to the axis of the battery 1 so that the total amount of coke from the chamber 2 is distributed as evenly as possible over the surface of the coke receptacle 3. The coke receptacle can be successively closed with a lid 15, 15a.

The sloping bottom surface 14 (FIG. 3) of the coke receptacle 3 is occupied in the example with cooling walls 4 which are perpendicular to the axis of the battery 1 and which are at a distance of z. B. have 40 cm. Cooling walls 4, floor surface 14, outer walls 10 (Fig. 2) and Lid 15 (Fig. 3) of the coke receptacle 3 are formed in the example as a hollow body and act as a steam generator.

The feed water is e.g. B. the coke receptacle 3 is fed via a permanently connected, windable, flexible line 11. The steam produced (z. B. 5 bar) is via a flexible line 12 also permanently connected to an expansion tank 8 and from there z. B. the ancillary plant 9 fed.

The coke remains in the container 3 until a second, similar container 3a, which is assigned to the same drive element 20, is charged with coke and closed with a lid 15a described above.

During the dwell time of the coke in the container 3 or 3a in front of the battery 1 of z. B. 10 minutes the temperature of the coke on z. B. lowered 800 ° C, producing about 130 kg of steam / t of coke. Then the lid 15 of the container 3 is removed while driving under the extinguishing tower 5 and the coke is cooled to ambient temperature by spraying with water. The water and coke discharge 16, which has a bottom bar 22 which is bent at right angles and is provided with water outlet holes 21, is brought into position 16a in which the indicated water outlet holes are exposed.

The coke is transferred to the coke ramp 6 in a known manner, the water and coke discharge 16 being brought into the discharge position 16b.

A modification of the exemplary embodiment shown in FIGS. 1 to 3 is that, according to FIG. 2, the pollutant-free steam generated is not used, but is released into the atmosphere via a chimney 13 without pressure.

In the modification of the device shown in FIG. 4, the cooling walls 4, the outer walls 10, the bottom surface 14 and the cover 15 are designed as water coolers.

The cooling water is removed from a cooling water channel 17 with the aid of a pump 19. The heated return cooling water is fed to the cooling tower 7 via a channel 18.

Another option is z. B. in that in the case of steam generation a feed water tank carried on the drive member 20 and periodically filled.

Claims (1)

1. A transportable coke-receiving container for the direct and indirect cooling of coke, having cooling walls for indirect heat exchange and a laterally arranged closable coke discharge flap, characterized in that the container (3) is provided with a closable cooling cover (15) and the coke discharge flap (16) comprises a floor ledge (22) bent at a right angle and provided with water discharge holes (21), and a plurality of cooling walls (4) disposed vertically and parallel to the end faces are arranged in the container (3).

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