DD264971A1 - DEVICE FOR THE INTENSE MIXTURE OF SURFACE-HARDENED RAW COAL WITH DISPOSED DRY FEED AND THE SWIVEL LAYER - Google Patents

Abstract

The invention relates to a device for better mixing of surface moist Schuettguetern in a fluidized bed, especially in steam fluidized bed drying plants with upper entry for the drying of raw fine coal. For the purpose of binding the surface moisture, dust is precipitated from the exhaust steam within the drying plant and this dry dust is fed to the moist crop so that good mixing takes place in the falling section between the entry and the fluidized bed surface. The deposition takes place via impact converters and guide devices. Fig. 1

Description

arranged. By the upward vent 11, a calming chamber 5 is provided, in which the Abdampfstrom is deflected, so that the dust is increased.

At the exhaust pipe 7 is a the exhaust port 11 surrounds around, extending to the container lid 12 widening Prallsichter β arranged for the separation of dust from the exhaust steam 2. Below the impact sifter β is a kragonartig the Discharge pipe 7 enclosing, obliquely inclined to the falling distance of the raw fine coal 1 baffle 9, the z. B. in the manner of a Strömungsleitkegels can be performed (Fig. 2), arranged so that the deposited dust 3 in the fall of the Raw coal is passed. With 8 arranged in dor fall track baffle is called. The operation of the device is the following. The raw fine coal 1 is metered from above through the rotary valve 4 in the container 13 of the Steam fluidized bed drying plant registered. SIo hits on her fall course, from the container lid 12 to the fluidized bed

groove the baffle 8, on which also the separated dry coal dust 3 is directed by the guide plate 9, on. This is followed by intensive mixing of the raw carbon with the dust, so that a large part of the surface moisture is bound. The baffle 8 also causes at the same time a wide distribution of the so mixed entry material on the.

Fluidized bed. In an embodiment of the invention, depending on the size and shape of the drying plant also several baffles

and baffles are placed in the upper part of the fluidized bed tank.

Advantages of the invention:

- No expenses in powered transport and mixing equipment.

- No circulation of already dried material outside the drying plant.

- Less contamination of the cyclone for the dust removal from the exhaust steam, as already a large part of the dust «is deposited within the drying plant.

- Good mixing of the entry material with the fluidized bed and thus continuous drying process.

Claims (1)

Device for the intensive mixing of surface wet raw fine coal with separated dry fines in the fluidized bed of a fluidized bed drying plant in which the wet raw coal is fed from above via an entry member of the fluidized bed, characterized in that in the upper part of the drying plant between fluidized bed (10) u · > ύ container lid ( 12) the exhaust pipe (7) for the exhaust steam (2) with its outlet opening (11) is arranged upwards so that a calming space (5) is formed, wherein the exhaust pipe (7) a the exhaust opening (11) surrounds around, until to the container lid (12) widening impact classifier (6) for separating dust from the exhaust steam is arranged and that below the impact sifter (6) a collar like the exhaust pipe (7) enclosing, obliquely inclined to the falling distance of the raw coal baffle (9) is arranged so that the separated dust is arranged on a Pr in the falling section of the raw coal Pr Allblech (8) with the raw fine coal intensively mixed. H'drzu 1 page drawings Field of application of the invention The invention relates to a device for the intensive mixing of surface wet raw fine coal with separated dry fines and the fluidized bed of a fluidized bed drying plant. Characteristic of the known technical solutions Surface moisture Raw fine coal (lignite) tends to cake when concentrated in fluidized beds. The resulting ball grain is poorly dried in the drying processes and impaired by 6lne poor mixing with the fluidized bed, the maintenance of a uniform fluidized bed in the drying plant. For a better distribution of raw fine coal in a fluidized bed has been proposed ready to arrange a trough chain conveyor in the upper part of the fluidized bed, the bottom of which is provided with a plurality of mutually offset drop holes. Although a broad distribution of the raw fine coal is achieved above the fluidized bed of the drying plant, the surface moisture of the raw fine coal is not degraded. Furthermore, drive energy is required for the relatively expensive trough chain conveyor. From DE OS 2943558 it is known to enter mechanically pre-dewatered sewage sludge in a fluidized bed drying plant to granulate this previously with already dried material. Oabei a part of the dried material from the dryer must be transported in a dry granulate silo and fed from this one M'schgranulator. In the mixing granulator, the dry granulate is loaded with the wet sewage sludge and then fed back to the Wirbelechichttrccknungsanlage. Although the surface moisture of the sewage sludge is bound with this method, it is always necessary to move already dried material through the drying plant again and do so with considerable technical effort and drive energy. ZIaI the invention The aim of the invention is to bind the surface moisture of raw fine coal in an economic way before the task in a fluidized bed. Explanation of the essence of the invention The invention has for its object to provide a device for steam fluidized bed drying systems, which makes it possible to mix surface wet raw carbon without consuming transport and mixing equipment and without additional drive energy with a dry material before the fluidized bed. According to the invention, this object is achieved in that the exhaust pipe for the exhaust steam is arranged with its exhaust opening upwards in the upper part of the drying plant between the fluidized bed and the container lid, so that a calming space is formed, wherein the exhaust pipe surrounding the exhaust opening around, extending to the container lid, Impact sifter is arranged to separate dust from the exhaust steam. Below the impact sifter, a collared like the exhaust pipe enclosing obliquely inclined to the falling distance of the raw coal baffle so engeordnet that dor deposited dust is intensively mixed on a arranged in the falling distance of the raw carbon baffle with the raw fine coal and distributed widely distributed to the fluidized bed. AusfOhrungsbelsplel The invention will be explained in more detail with reference to an embodiment. In the drawing, the upper part of a fluidized bed container 13 is shown schematically. Between the fluidized bed 10 and the container lid 12 is the exhaust pipe 7 with the exhaust opening 11 for the exhaust steam 2 in the direction of the container cover 12th