DE923548C - Melting chamber boiler - Google Patents

Description

Melting chamber boiler The invention relates to a melting chamber boiler for finely divided fuel, especially coal dust, whose slag is constantly is withdrawn downwards in the liquid state, from one of cooling tubes formed, movable within the boiler frame, with a slag discharge nozzle equipped funnel, which is carried freely movable by the suspended boiler tubes will.

With such boilers there is the difficulty of the resulting liquid Discharge slag to the outside without the relative displaceability of the Boiler tube system opposite the fixed boiler frame at the point of contact False air penetrates the melting chamber from the outside.

A boiler design is already known in which the penetration of false air in the combustion chamber is avoided by the fact that the movable boiler system is completely enclosed airtight by a fixed masonry, wherein the funnel walls of the movable pipe system at their lower end the corresponding overlap the inclined inner walls of the fixed outlet connection.

This known design has the disadvantage that it is used in boilers Cannot be used with liquid purification, because even with a slight change in load the solidifying slag the relative displaceability at the point of overlap prevented, so that when the boiler tubes are working, destruction of this point is inevitable is.

Another disadvantage of the older version is that that the overlap is provided at a very hot point, so that with one Warping and throwing must be expected. In addition, the point of overlap is heavy accessible. A guide for the movable boiler funnel at the point of overlap is not possible, so that the funnel can tilt.

All of these difficulties and disadvantages are eliminated with the invention eliminated by the fact that a slag hopper surrounding and firmly connected to it, Outer housing formed from heat protection walls, closed at the bottom the fixed heat protection walls of the boiler frame are sealed by overlapping is.

This embodiment according to the invention is because of the almost the same Coefficient of thermal expansion of the thermal barrier wall surrounding the slag funnel Housing and the fixed heat protection wall of the boiler frame provide a good seal achieved between the two overlapping walls, so that through the the slag funnel surrounding housing, the supply of cold air into the funnel is effectively avoided.

Another advantage of the invention is that the in Air trapped in the housing provides additional thermal protection for the slag hopper forms.

The embodiment proposed by the invention also offers the possibility of to use the space below the funnel by installing water pipes.

Finally, the sealing point is located at a point that is easily accessible from the outside and a relatively cold place, far away from the slag outlet, so that they can be observed well and warping, throwing or clogging by freezing Slag is completely excluded. In addition, the point of overlap enables a good guidance of the movable boiler system in the fixed boiler frame, so that tilting is also excluded.

Further features of the invention are contained in the subclaims, which are only valid in connection with the main claim.

The object of the invention is explained in more detail in the drawing using an exemplary embodiment, namely Fig. I shows the combustion chamber of a radiation boiler designed according to the invention in a vertical partial section and Fig. 2 the object of Fig. I in a horizontal section along line AA .

In the drawing, i denotes the boiler frame, which in lined upper part at the level of the combustion chamber 2 with insulating heat barriers 3 is. The combustion chamber 2 is on all sides by closely spaced, vertical Riser pipes 4 are cooled, the lower pipe parts 4a of which correspond to the slope of the funnel walls 5 accordingly inwards and then downwards and backwards .are bent to on it with the pipe parts 4b, 4c and 4d, combined in groups, in the side wall collector 6 to merge. The collectors 6 of each side wall are on vertical downpipes 7 suspended and connected to upper boiler drums, not shown.

According to the invention from the brick funnel walls 5 and the tube parts 4a consisting of a funnel-shaped part of the combustion chamber 2 in one the side walls 8 and the bottom 9 with funnel outlet stubs existing outer Housing 8.9 included, which is relatively displaceable with respect to the boiler frame i forms the lower end of the boiler system and is freely movable from the suspended ones Boiler tubes 4 and 7 is worn.

The side walls 8 of the housing overlap at their upper ends lower ends of the fixed heat barriers 3 of the boiler frame i and allow as a result, these parts slide past each other when expanding or contracting the boiler tubes.

The wall walls 8 of the housing enclose the side wall collector on the housing bottom 9 6. The funnel walls 5 are above the funnel through the vertical side walls 12 extended. Only bare riser pipes are used in the area of the combustion chamber, which form the radiant heating surfaces, while the pipe parts 4a within the funnel are covered with a thin layer of fireclay i i.

The funnel walls 5 surrounding the slag funnel are corresponding bent outwards along the pipe run in the area of the funnel outlet opening and are supported with their ends 2o on the pipe parts 4b leading to the collectors 6 away.

According to the pyramid shape of the funnel, each funnel wall 5 has a trapezoidal shape. The pipe framework of the funnel walls 5 is formed from the closely adjacent, inwardly bent parts 4a of the parallel riser pipes 4, which is made possible by the fact that the parallel pipe parts of each side wall pipe group pipe by pipe only up to the boundary line 13 each two adjacent funnel walls and then after are bent at the bottom (see Fig. 2). As a result, the tube parts 4a forming the funnel walls are each time a little longer from the sides towards the center of the wall, while the middle tube parts, which are passed through to the vicinity of the square funnel passage opening 14, have the same length. As a result of this pipe routing, all riser pipes on each side wall are involved in the funnel and bottom formation, so that there is an even distribution of weight and pipe loading, whereby the pipe suspensions are significantly relieved.

In the manner described above one obtains a symmetrical, Self-contained pipe system consisting of the straight downpipes and the ones below the burner 15 is bent in a funnel shape and at the seams of the funnel walls and at the flow opening of the funnel to the headers directed boiler risers formed and hung on the upper headers of the boiler and a free one Allowed drainage of the molten slag from the combustion chamber. the Coal dust burners 15 are in the lower part of the combustion chamber 2 in the corners of two adjacent side walls arranged one above the other so that the dust flames cross in the middle of the funnel mouth or touch an imaginary circle. Instead of corner firing, any other burner arrangement can also be used.

The funnel outlet stub io is below the housing bottom 9 with an annular channel 16 surrounded by a ring of openings 17 with the interior of the outlet connection io and to the natural or an artificial one Induced draft of the boiler is connected.

A water bath 18 is provided below the funnel outlet nozzle io, into which the drainage nozzle protrudes. The liquid slag falls through the water bath on an inclined conveyor belt i9 and is continuously moved outwards by this transported away.

The invention is not limited to that described above and in the Embodiment shown in the drawing is limited. So could z. B. in place a combustion chamber with a quadrangular or square cross-section, as well as any other Cross-sectional shape of the combustion chamber can be selected without affecting the basic Construction of the boiler would be changed somewhat.

Claims (7)

PATENT CLAIMS: i. Melting chamber boiler for finely divided fuel, in particular coal dust, the slag of which is constantly withdrawn in the liquid state, namely from a funnel formed from cooling tubes, movable within the boiler frame, provided with a slag discharge nozzle, which is freely movably supported by the suspended boiler tubes, characterized that an outer housing, which surrounds the slag funnel (5) and is firmly connected to it, formed from heat protection walls (8, 9) and closed at the bottom, is sealed by overlapping on the fixed heat protection walls (3) of the boiler frame (i). 2. Melting chamber boiler according to claim i, characterized in that the weight of the lower, outer housing (8, 9) including slag funnel (5) and slag discharge nozzle (1o) and the lower one Collectors (6) evenly and in the same way on the individual tube groups (4,7) is distributed on each side wall of the boiler. 3. Melting chamber boiler according to claim i and 2, characterized in that the closely adjacent, vertical Radiant tubes (. 4) on each side of the shaft-like combustion chamber (2) directly are bent and guided below the pulverized coal burner (15) so that in the middle of the lower part of the combustion chamber one from the tube parts (4a) of each side wall formed, by trapezoidal surfaces bounded slag funnel arises. Melting chamber boiler according to claims i to 3, characterized in that the individual elements are parallel to one another lying, obliquely bent down pipe parts (4a) of each side wall pipe group Tube for tube only up to the joint (13) of two adjacent hopper walls (5) carried out and then bent downwards, in such a way that the funnel walls forming pipe parts (4a) from the sides towards the center of the wall each time a small piece become longer so that trapezoidal funnel walls are formed. 5. Melting chamber boiler according to claim r_ to 4., characterized in that the central pipe parts (4a) evenly carried out up to the passage opening (14) of the slag funnel and then turned backwards. 6. melting chamber boiler according to claim i to 5, characterized in that the at the lower end of the funnel walls (5) backwards bent pipe ends (4b to 4d) grouped together to the corresponding Collectors (6) are connected to each side wall. 7. Melting chamber boiler according to claim i to 6, characterized in that the collector (6) is suspended in a manner known per se on the vertically extending downpipes (7) of each side wall and installed directly in the side walls (8) of the housing (8, 9) are. B. Melting chamber boiler according to claims i to 7, characterized in that the outer heat protection walls (5) forming the slag funnel are bent back in accordance with the pipe run in the area of the funnel outlet opening (14) and extend with their lower wall ends (2o) towards the collectors (6 ) support the leading pipe parts (4 b). Cited publications: German Patent Nos. 617 872, 630 395, 673 898, 695 998, 733 967, 743 651, 743 685; . USA. Patent Nos 2,087,801, 56o 2 268, 2330: 240; VDI magazine, 1948, p. 203; Announcements from the Association of Large Boiler Owners, 1943, pp. 2o5 to 211; Feuerungstechnik, 1938, p.311; Archives for heat management and steam boiler beings, 1942, p. 152; Power, March 1949, p. 122, October 1948, p. 28; Power Generation, Jan 1949, p. 103; Combustion, August 1945, p. 32 and 34, October 1945 p. 37/38; Combustion Engineering, 1948, pp. 9, 53; 2J # 68 and 15, 42.