DE2341331A1 - Rotary drum dryer lime powder - has flue gases from burner passed through rotary pipe and back via surrounding double jacket - Google Patents

Abstract

Drum dryer and heater for lime powder or other fine-milled solids has a conveyor screw surrounding a rotary pipe and surrounded by a double jacket, with a feeder and a discharger, a burner and combustion chamber and a chimney; the rotary pipe and jacket are for flow of flue gas. The rotary pipe is also a combustion chamber and the burner opens into one end of it, in the region where the feeder adjoins the pipe, and the chimney adjoins the double jacket. The other end of the pipe is connected to a deflection channel opening into the jacket, so that flue gases are conducted in co-current flow in the pipe and countercurrently in the jacket, w.r.t. the material. High thermal efficiency is combined with compact arrangement.

Description

Andrejewski, Honke & Gesthuysen patent attorneys

Physicist

Dr. Walter Andrejewski

Graduate engineer

Dr.-lng. Manfred Honk

ho oat / w graduate engineer

Legal file: ^ ^ / H. Hans Dieter Gesthuysen

P at e nt note

Dipl.-Ing. Abder-Rahim Khudruj

53 Bonn-Lengsdorf

In Hohnderfeld 7

4300 Essen, August 14, 1973 Thaatarplatz 3

Drum dryer

Drum dryers are known in various embodiments and are used to dry and heat lime flour or the like. Finely ground pest substances. In particular are such known that from a rotary tube with this surrounding screw conveyor and the screw conveyor surrounding double jacket as well consist of a loading and unloading device, a burner with an associated combustion chamber and a chimney, with a rotary tube and double jacket are set up for flue gas guidance. In a known drum dryer of such an embodiment the burner and combustion chamber are arranged separately from the rotary tube and double jacket. The combustion chamber, however, is on the same Pipe end connected to both the rotating pipe and the double jacket, while the feed device and chimney are assigned to the other pipe end or double jacket end. In this way

509808/0668

Andreiewski, Honke & Gesthuysen, patent attorneys, 4300 Essen 1, Theaterplatz

The flue gases flow through the rotary tube and the double jacket in the same direction and against the direction of movement of the conveyed material, so that practically a countercurrent principle is realized both in the rotary tube and in the Donpelmatel, - In another known embodiment, in which the rotary tube itself is not set up to carry pauch gases, but only the screw conveyor surrounding double jacket, which also opens separately from_ Rotary tube and double jacket arranged combustion chamber with burner in the double jacket. Located in the mouth area furthermore the chimney, while the feed device e'en is assigned to the other end of the rotary tube. Nevertheless, this drum dryer also works practically on the countercurrent principle, namely against the direction of movement of the conveyed material.

The drum dryers described above are satisfactory on the one hand not in terms of their thermal efficiency, on the other hand, their construction is due to the separate Space-consuming arrangement of burner and combustion chamber. The invention aims to cut these disadvantages.

The invention is based on the object of creating a drum dryer which is characterized by an extremely high thermal efficiency and, at the same time, a compact design.

509808/0666

Andrejewski, Honke & Gesthuysen, patent attorneys, 4300 Essen 1, Theaterplcite

The invention relates to a drum dryer for drying and heating lime flour o ,. like finely ground solids, consisting of a rotary tube with a screw conveyor surrounding it and a double jacket surrounding the screw conveyor as well as a loading and unloading device, a burner with an assigned combustion chamber and a chimney, with rotating tube and double jacket set up for flue gas guidance sind.- The invention consists in the fact that the rotary tube is designed as a combustion chamber and the Burner opens into one end of the pipe, and that in the area of the burner tube end, the feed device to the rotary tube and the chimney to the double jacket and the other The pipe end of the rotary tube is connected to a deflecting duct opening into the double jacket and thereby the flue gases in the Rotary tube are guided in cocurrent and in the double jacket in countercurrent with the movement of the material to be conveyed, - According to the teaching of the invention The rotary tube also serves as a combustion chamber, with the burner flame burning inside the rotary tube. The heat transfer to the lime flour is indirect, but very intense, because it is practically a combination of convection and radiation drying is realized. The biggest Part of the heat given off by the flue gases is transferred through the rotary tube wall and the screw conveyor in the same direction moved Kalkraehl transferred. The residual heat is used by the Transferring smoke gases flowing through the double jacket through the inner jacket to the lime powder moving in the opposite direction. The flue gases finally leave the double jacket ■ and are led to the chimney. Both tube ends of the rotary tube are sealed by means of stuffing boxes to prevent leakage

Andrejewski, Honke & Gesthuysen, patent attorneys, 4300 Essen 1, Theaterplatz

to prevent the smoke gases from entering the atmosphere. The stuffing boxes allow easy, the heat expansion of the rotary tube in the axial and radial direction. In order to eliminate the risk of clogging, the invention also provides that the pitch of the screw conveyor in the feed area is lower than in the conveying area. In addition, the double jacket ' have internal longitudinal ribs to achieve an enlargement of the heat transfer surfaces, but also for improved Management of the flue gases.

The advantages achieved by the invention are essentially to be seen in the fact that a drum dryer for Drying and heating of veal meal or the like finely ground Solids is realized, which is characterized by optimal thermal efficiency, in addition by a particularly compact, space-saving design because there is no separate arrangement of burner and combustion chamber. In fact, the inventive Drum ^ dryer the drying and heating of calf meal or the like. fine ground substances in a particularly economical way, which results in a high increase in performance.

In the following the invention is explained in more detail with reference to a drawing showing only one embodiment. The single figure shows a drum dryer according to the invention in a visual representation.

Andrejewski, Honk »& Gesthuysen, patent attorneys, 4300Essen !, Theaterplatz

In the figure is a drum dryer for drying and heating of lime flour or similar finely ground solids shown, the basic structure of a rotary tube 1 with this surrounding screw conveyor 2 and the Conveyor screw surrounding double jacket 3 and from a loading and unloading device 4, 5, a burner 6 with associated combustion chamber 7 and a chimney 8, with rotating tube 1 and double jacket 3 set up for flue gas guidance are. The rotary tube 1 has a conventional running ring bearing 9 and can be equipped with a toothed ring or chain ring for drive by an electric motor 11. The double jacket. 3 also has the usual supports 12 Rotary tube 1 is also designed as a combustion chamber. For this purpose, the burner 6 opens directly into one end of the pipe Rotary tube 1. It is also provided that in the area of the burner tube end, the feed device 4 to the other The tube end of the rotary tube opens into the double jacket 3 Connected deflection channel 13 and thereby the flue gases in the rotary tube 1 in cocurrent and in the double jacket 3 in countercurrent with the movement of the conveyed goods. the Flue gas routing is indicated by arrows. The pipe ends of the rotary tube are sealed by means of stuffing boxes 14. The incline of the screw conveyor 2 is chosen to be lower in the task area than in the conveyable area. The double coat 3 has internal longitudinal ribs 13, which is only is indicated. In addition, the usual vents are 16 provided for the rotary tube 1, the escape allow the moisture from the lime powder or conveyed material. The entire drum dryer is also designed to avoid this Surrounding heat losses with an insulating jacket 17.

509 8 08/0666.

Claims (4)

Andrejewski, Honke & Gesthuysen, patent attorneys, 4300 Essen 1, Theaterplatz 3 Patent claims f lj drum dryer for drying and heating lime powder or the like. finely ground solids, consisting of a rotary tube with a conveyor screw surrounding it and a double jacket surrounding the conveyor screw, as well as a feed and removal device, a burner with an associated combustion chamber and a chimney, the rotary tube and double jacket being set up for flue gas guidance, characterized in that the rotary tube (1) at the same time designed as a combustion chamber and for this purpose the burner (6) opens into one tube end, and that in the area of the burner tube end the feed device (4) to the rotary tube (1) and the chimney (8) to the double jacket (3 ) and to the other pipe end of the rotary tube (1) a deflection duct (13) opening into the double jacket (3) is connected and the flue gases in the rotary tube (IJ in cocurrent and in the double jacket (3) in countercurrent with the direction of movement of the conveyed goods are guided. 2. Drum dryer according to claim 1, characterized in that that the tube ends of the rotating tube β (1) by means of stuffing boxes (14) are sealed. 3. Drum dryer according to claims 1 or 2, characterized in that the pitch of the screw conveyor (2) is selected to be lower in the feed area than in the conveying area. 4. Drum dryer according to one of claims 1 to 3, characterized characterized in that the double jacket (3) has internal longitudinal ribs (15). 509808/0666