FI85758B - FOERBRAENNINGSANLAEGGNING. - Google Patents

Description

85758

combustion System

The invention relates to an incineration plant as defined in more detail in the preamble of the claim. The combustion plant according to the invention comprises, in order to provide a circulating mass process, a combination of a reactor chamber and at least one particle separator. In the lower part of the reactor chamber are arranged so-called for forming a fluidized bed, a grate structure having means 10 for supplying fuel to the grate structure, means for removing coarse material in the fluidized bed from the top of the grate structure, and means for supplying air to the grate structure. The particle separator can be of the so-called structure. a cyclone separator having two substantially nested sheaths whose central axes are parallel and substantially congruent. The first outer jacket is provided with a solids flue gas inlet arrangement generated in the fluidized bed of the reactor chamber Lei and at least one solids return channel separated in the particle separator in communication with the grate structure of the reactor chamber to return solids to the fluidized bed. The second, inner jacket is arranged ... in connection with the post-combustion process stage '; 25 with substantially solid-free flue gas · ;;; to pass through said jacket to said post-combustion process step. Most commonly, the reactor chamber has a wall structure substantially arranged as a heat transfer surface, wherein the wall structure comprises a tubular structure inside which a heat transfer medium flow is arranged.

. ···. Combustion installations such as those described above and are known for many different types of design applications.

. Most commonly, the particle separator is located outside the reactor chamber, but it is also known to place 2 85758 particle separators inside the reactor chamber. The present invention can be applied to both basic constructions.

5 One of the problems associated with currently used combustion plants is the supply of fuel and the so-called the complexity and susceptibility of structures used to remove coarse material. Accordingly, it is an object of the present invention to provide an combustion apparatus 10 in which, in particular, the above-mentioned important components related to the circulating mass process are arranged in such a way as to provide an improved and highly functional construction.

To achieve these objects, the combustion plant according to the invention is mainly characterized in that the means for supplying fuel to the grate structure and means for removing coarse material from the grate structure are formed into at least one group 20 which passes through the grate structure at substantially the same point. The solution provides a structurally simple structure that enables reliable material transfers.

According to a particularly preferred embodiment; the outlet of the solids return channel from the particle separator is arranged on at least one of the above-mentioned groups. This solution provides a compact structure in which both the fuel supply, the removal of the coarse material 30 and the return of solids can be placed in connection with the grate structure as a single unit.

Other preferred claims further disclose some preferred embodiments of the incinerator according to the invention.

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3 85758

The invention is illustrated in more detail in the following description, in which reference is made to the accompanying drawing, which shows a cross-section of a combustion apparatus according to the invention in terms of a grate structure.

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With regard to the general structure of the combustion plant, the applicant refers to the prior art and in particular to the parallel application "Combustion plant", the main object of which is in particular a special flue gas inlet arrangement for

In the drawing, reference numeral 1 shows a part of the cooled grate structure in the reactor chamber R, in which an opening 2 is formed by means of an annular feed chamber 4 connected to the cooling pipes 3 of the grate structure. The annular supply chamber 4 20 is used to supply the heat transfer medium to the return duct.

· * - · An opening 5 is formed in the opening 2 below the grate structure 1, outside which an air distribution space 6 is formed on the inside of the reactor chamber, from which combustion air passes through the nozzle members passing through the grate structure to the fluidized bed (not shown). A vertical supply pipe 7 is passed through the housing 5 through the bottom of the reactor chamber, terminating 30 at the level of the grate structure 1 in the distribution chamber 8, from which further protrudes from the side surfaces of the distribution chamber in the embodiment shown: four substantially horizontal fuel supply pipes 9 located vertically. above the grate structure 1 and placed at an angle of 90 ° to each other when viewed from above. The lower part of the supply pipe 7 has a separator member 10 4 85758 for providing a fuel supply of suitable composition. Parts 7, 8 and 9 form means for supplying fuel to the grate structure substantially radially with respect to the longitudinal direction of the supply pipe.

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At the supply chamber 4, from the plane of the upper surface 1a of the grate structure 1 coated with ceramic material, a conical coarse material outlet pipe 11 starts at its upper end, the lower end of which also extends into the overpressure chamber 12 inside the housing 5. the countercurrent separation principle returns the fine material among the coarse material back to the Lei layer. At the bottom of the overpressure chamber 12 there is an outlet pipe 13 for coarse material and a blower pipe 14 for blowing the gaseous pressure medium required by the countercurrent separation principle into the overpressure chamber 12. The outlet pipe 11 surrounds the supply pipe 7, leaving the coarse material along the annular channel. The supply pipe 7 is further arranged inside the overpressure-20 chamber 12.

The outlet of the solids return duct 15 is 1: located above the distribution chamber 8 at a distance:. its upper surface or the like, and the drawing *. In the application example according to 25, the return channel 15 is'! formed as a heat transfer surface, wherein the feed chamber; from which the vertical supply pipes 16 (4) exit upwards into an annular distribution chamber 17 at the bottom of the return duct 15, from which further the pipes 18 inside the ceramic protective layer of the wall of the return duct 30 lead the heat transfer medium upwards, e.g. Combustion equipment "is shown. It is preferred that in the above case at least one group formed by the members 7, 8, 9 and 11 · 'is arranged on the center line of a vertical cylindrical reactor chamber R with a circular horizontal cross-section, where t; The center lines of the inlet pipe 7 and the outlet pipe 11 coincide with the center line of said reactor chamber R. This results in a symmetrical fuel supply and a return of coarse material. The solids return channel 5 can then advantageously be a vertical tube, the upper part of which is attached to the lower part of the cyclone separator, whereby its center line also substantially coincides with the center line of the reactor chamber R.

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Claims (10)

A combustion apparatus comprising a circulating mass process for providing: a reactor chamber (R), in the lower part of which a so-called to form a fluidized bed grate structure (1), means for supplying fuel above the grate structure 10 to the fluidized bed, means for removing coarse material in the fluidized bed from the grate structure, and means for supplying air to the fluidized bed; the so-called. a return channel for returning solids, in particular to the fluidized bed, characterized in that the means for supplying fuel to the grate structure (7, 8, 9) and means for removing coarse material contained in the fuel (11) are formed in at least one group passing through the grate structure at substantially the same point. Combustion apparatus according to Claim 1, characterized in that the outlet opening of the return duct (15) or the like is arranged on at least one of the above-mentioned groups. Combustion plant according to claim 1, characterized in that the means for supplying fuel comprise: 35 * \ - preferably a substantially vertical supply pipe (7), and above the grate structure (1), a body connected to the upper part of the supply pipe ♦ # 7 85758 (7) 8, 9) for supplying fuel substantially radially with respect to the longitudinal direction of the supply pipe to the grate structure (1). Combustion apparatus according to claim 3, characterized in that said body (8, 9) comprises a chamber (8) in connection with which a plurality of feed members, preferably tubular members (9), are arranged to project in a radially substantially horizontal direction. Combustion apparatus according to Claims 1 and 3, characterized in that a tubular coarse material outlet pipe (11) or the like is arranged substantially longitudinally around the supply pipe (7) and is connected to said pipe. into the opening of the group (2). Combustion apparatus according to Claim 5, characterized in that the discharge duct (11) is arranged to terminate in a separator chamber (12) in which it is arranged. . a gaseous pressure medium flow for separating the finer material operating on the countercurrent difference principle from the coarse material and returning it along said outlet channel (11) onto the grate structure (1) to the fluidized bed and to the lower part thereof *. *: An outlet pipe (13) is placed on coarse material. 6 85758 Combustion plant according to Claim 5, characterized in that the upper part of the outlet pipe (11) is,. conically expanding and associated with to the edge portion of the group opening (2). Combustion plant according to Claim 1, characterized in that at least one group of members (7, 8, 9 and 11) is arranged in a vertical position on the center line of a reactor chamber (R) with a circular horizontal cross-section. Β 85758 Combustion plant according to Claims 1, 2 and 8, characterized in that the return duct (15) is vertical and arranged so that its center line 5 coincides with the center line of the reactor chamber (R). Combustion apparatus according to claims 1 and 2, characterized in that the opening (2) through which said group passes through the grate structure preferably comprises in its edge part a feed chamber (4) into which the heat transfer medium is arranged to be fed through the grate structure (1). 16) or the like for supplying a heat transfer medium to a return duct, which is preferably formed as a wall-mounted tubular heat transfer surface. li 9 55758