FR2748552A1 - INCINERATION GRID OF HOUSEHOLD WASTE - Google Patents

Abstract

An incinerator grille consists of a series of alternating and overlapping fixed (9) and moving bars with holes (10A) for an air flow from a blower chamber beneath the grille. The grille is bounded at the sides by at least one vertical edge plate (11) which has one or more recesses (11A) for the edge of a bar. The grille can have two edge plates, each with a series of recesses for the bar edges. Each recess extends from the lower edge (11B) of the plate and has an upper edge (11C) corresponding to the shape of a fixed bar.

Description

INCINERATION GRID OF HOUSEHOLD WASTE.

  The present invention relates to a grid

  incineration of household waste.

  It relates more specifically to a household waste incineration grid consists of a row of fixed bars and movable bars translated on them, these fixed and movable bars being interposed and provided with openings for the passage of air blowing from a blowing chamber arranged under the grid, said row being limited laterally by at least one plate of

substantially vertical bank.

  Such a grid is found in a household waste incineration plant where the waste is introduced via a hopper into a well, is pushed to the bottom of this well by a drawer towards the inclined grate where waste combustion is carried out and that their transfer to the end of the grid where they are evacuated in a ferry

cooling.

  In such a grid, the bars are currently juxtaposed with minimal clearance against the edge plate. This minimum clearance must allow the differential expansion of the bars and the edge plate and the translation of the movable bars. Now by this game, passes the blown air blown into the blowing chamber disposed under the

  grid and escapes vertically along the edge plate.

  Due to its flow, this air contributes very little to the combustion of waste and constitutes a non-hazardous air leak.

  negligible since, in the case of a grid limited laterally by two edge plates, about 50% of the blowing air is thus lost.

  The invention solves this problem and to do this, according to the invention, said edge plate is

  provided with at least one recess in which is fitted a lateral edge of a bar.

  This arrangement has three advantages.

  It is thus obtained a passage baffle air in said game which decreases its flow. It is thus possible to effectively regulate the air flow of

  blowing and reduce emissions of nitrogen oxides.

  At the outlet of the baffle passage, the air flows in a substantially horizontal direction and thus penetrates the mass of waste, thus effectively participating in their combustion. The game in the form of baffle opposes the passage through the grid of fine particles or small metal parts from the mass of waste. On the contrary, the particles tend to accumulate at the horizontal mouth of the baffle passage and to block it, again limiting air leakage. In the current case of a grid limited laterally by two vertical edge plates. each edge plate is provided with a series of recesses each receiving a fixed bar. For reasons of ease of manufacture, preferably, this arrangement relates only to the fixed bars which, by the conventional constitution of such a grid, correspond to about 85% of the length of the side games. Preferably, each recess has the form of a vertical planar rebate, extending to the lower edge of the edge plate and whose upper edge has substantially the profile of the corresponding fixed bar. In this way, the bar is fitted into the rabbet with a minimum vertical clearance relative to the bottom

  of the latter and a minimum horizontal clearance with respect to the upper edge thereof.

  The invention is described below in more detail with the help of figures representing only one embodiment.

  Figure 1 is a partial vertical sectional view of an incineration plant for household waste.

  Figure 2 is a partial sectional view

  longitudinal of an incineration grid.

  Figure 3 is a front view of a side plate forming part of such an incineration grid according to the invention. Figure 4 is a partial cross-sectional view of a fixed bar of such a grid according to the invention. FIG. 1 is intended to locate an incineration grid, object of the invention, in an installation

waste incineration.

  The waste is dumped into a hopper 1 and falls into a well 2 at the bottom of which they are received on a horizontal surface and pushed by a pusher 3 on the grate

incineration 4 inclined.

  Under this grid 4 formed of transverse bars provided with orifices, there is a blowing chamber 5 into which combustion air is blown, which passes through said orifices and burns the mass of waste which is found on the grid 4. Above of the grid 4, the fumes are evacuated in a conduit 8 to a device of

smoke treatment.

  The bars of the grid 4 are alternately fixed or movable, as will be seen more precisely later, and progressively move the mass of burnt waste to an evacuation well 6 o the waste falls into a cooling tank 7 and are recovered. FIG. 2 shows in more detail the incineration grid 4. It consists of a row of fixed bars 9 and movable bars 10 translated on the latter, these fixed and movable bars being interposed and provided with orifices 9A. , 10A of blowing air passage. The support arrangement 13 of the fixed bars 9 and that of translation drive 14 of the movable bars 10 are schematically represented in the figure and generally consist of vertical supports.

  fixed for the first and movable beams for the second.

  The row of bars is laterally limited by a vertical edge plate 11 consisting of several panels juxtaposed and secured. In general, the grid comprises such a rim plate 11 on each of its lateral edges. As can be seen in FIG. 3, the edge plate 11 is provided with a series of recesses 11A in which the lateral edge of each fixed bar 9 is fitted. More precisely, each recess 11A is in the form of a flat bottom rabbet. vertical, extending to the lower edge 11B of the plate 11 and the upper edge 11C has substantially the profile of the fixed bar 9 corresponding. Each fixed bar 9 is fitted into a rabbet 11A as shown in FIG. 4. Between the edge plate 11 supported by a support structure 12 and the fixed bar 9 is made a minimum clearance taking into account the differential expansions. This clearance constitutes a baffled leakage passage of the blowing air located under the bars 9, 10 in the blowing chamber 5. This baffle passage results in a decrease in the leakage rate, a substantially horizontal flow of air at the exit of the passage and therefore an25 penetration of the air into the mass of waste and its contribution to the combustion of it and finally opposes

  the falling of fine solid particles which tend to the contrary to the butcher.

Claims (3)

  1) Incineration grid of household waste consists of a row of fixed bars (9) and movable bars (10) translated on them, these fixed and movable bars being interposed and provided with orifices (9A, 10A) of blowing air passage from a blowing chamber (5) disposed under the grid, said row being laterally limited by at least one substantially vertical edge plate (11), characterized in that said edge plate (11) is provided with at least one recess (11lA) in which is fitted a lateral edge of a bar. 2) grid according to claim 1 laterally limited by two vertical edge plates (11), characterized in that each edge plate is provided   a series of recesses (11A) each receiving a fixed bar (9).   3) Grid according to claim 1 or 2, characterized in that each recess (11A) has the shape of a vertical plane bottom rabbet, extending to the lower edge (liB)   of the plate and whose upper edge (11C) substantially has the profile of the corresponding fixed bar (9).