FR2595792A1 - IMPROVEMENTS IN FIXING PROTECTIVE ELEMENTS OF BOILER COMBUSTION CHAMBERS - Google Patents

Abstract

1. A method of protecting and fixing prefabricated refractory components, fixed to the walls of the combustion chambers of boilers, by means of hooking elements held by a refractory product, characterized in that the hooking element (10, 10', 10'') is protected by a layer of refractory material (14) ensuring, in addition, the connecting together by gluing of the refractory component (16) and of the hooking element, and that all the free spaces between the walls (12) of the boiler, the hooking elements (10, 10', 10'') and the refractory components (16) are filled with the bonding material.

Description

2595792 ,.

  The present invention relates to protection against corrosion and erosion of the combustion chambers of boilers. This invention applies more particularly, without being limited to this application, to the protection of the combustion chambers of boilers which equip incineration plants with household and industrial waste. It is known that, in household or industrial waste incineration plants, with heat recovery, it is necessary to protect the walls of the combustion chambers of boilers against corrosion, in the flame development zone, due to gases from the combustion of waste. Generally, such protection is ensured in the following way: a - either by means of a coating of refractory clay, based on silicon carbide, put in place, preferably by projection, on the tubular panels constituting the walls. of the combustion chamber. The disadvantage of this known solution lies in particular in that the lifespan of these rammers is short, which leads to rapid degradation of the coating in the most exposed areas, making necessary major repairs, which must be carried out frequently; b - either using prefabricated refractory parts, or shaped bricks, in particular made of silicon carbide, fixed to the walls of the boiler. The service life of these parts is excellent, especially when they are made of silicon carbide. Unfortunately, this solution requires the use of fragile anchoring or hanging elements, which destroy themselves.

  by corrosion, causing the refractory parts to fall.

  The object of this invention is to provide an improvement in the fixing of these prefabricated refractory parts, in order to avoid their corrosion.

  Consequently, this invention relates to a method of protecting and fixing prefabricated refractory parts, fixed to the walls of the combustion chambers of boilers by means of hooking elements, characterized in that

  that it consists, on the one hand, of protecting the fastening element with a layer of refractory product, and, on the other hand, of ensuring the connection between the refractory part and the corresponding fastening element, using the same refractory product.

  According to a characteristic of this invention, said refractory product

  may be chemically, hydraulically or otherwise, and may or may not contain silicon carbide.

  According to another characteristic of this invention, any form is communicated to the fastening element and to its housing in the refractory piece.

  suitable for improving fixation.

  Other characteristics and advantages of this invention will emerge from the description given below with reference to the appended drawing, which in itself

  polish various embodiments, devoid of any limiting character.

  In the drawing: - Figures 1 to 3 are partial views, in section, illustrating three examples of implementation of the invention; - Figures 4 to 6 illustrate, in section, various embodiments of refractory parts used by the invention; and,

  - Figure 7 is a sectional view of a variant of the invention.

  Referring to the drawings, and more particularly to Figures 1 to 3? it can be seen that, according to the invention, protection is provided for the anchoring elements 10 or hooking elements, such as 10, fixed to the tubular panels 12 constituting the walls of the combustion chamber of the boiler, using of a layer

  of refractory product 14, which may be chemically, hydraulically or otherwise, and which may or may not contain silicon carbide. Furthermore, still according to the invention, the same refractory product is used to ensure the connection between the refractory piece or brick 16 and its attachment element 10.

  In the embodiment of Figure 1, the fastening element 10 and its housing in the refractory piece 16 have walls with parallel or cylindrical faces, the layer of bonding product 14 ensuring the holding

by simple bonding.

  In the variant illustrated in FIG. 2, the hooking element 10 ′ is inclined or has a face inclined upwards, in "coat hangers", of

  so as to improve the resistance by gravity action.

  In the third exemplary embodiment illustrated by FIG. 3, a hooking element 10 "is used which has a larger section at its end than at its base, and which is positioned in a housing of the refractory piece 16 which has a corresponding shape. Thus, the layer 14 of bonding product ensures, after drying, a mechanical keying, which significantly improves the resistance. It is then possible to place refractory pieces on the ceiling. of the invention described above make it possible to replace a brick in the middle of a wall without

touch others.

  According to the invention, all the free spaces between the different rooms

  refractories 16 must be carefully filled with the bonding agent, 35 in order to avoid gas infiltration and pumping effects during temperature variations.

  According to the invention, the hooking elements 10 can be fixed either on the fins 12 (Figure 4), or on the tubes 18 of the tubular panels (Figure 5). Similarly, the refractory pieces 16 can cover a tube 18 (Fi40 gure 5) or several tubes (Fig. 6), the connection points then being either at

3 2595792

  right of the fin 12, or the right of the tube 18.

  According to this invention, the seal between the parts can be improved.

  refractory 16 by creating baffles 20 (Figure 7).

  In known manner, the housing of the refractory piece which receives the fastening element, such as 10, can be blind or through. If it is through, the filling of said housing with the bonding product is facilitated, but the protection of the refractory piece 16 is weak, whereas on the contrary, if it is blind, the filling of the housing is more difficult, but protection

is better.

  Of course, the refractory pieces may include one or more housings to receive the fastening elements. However, it is preferable to provide them with modest dimensions, with a single hooking element, for

avoid breaks.

  It remains to be understood that this invention is not limited to the examples of embodiment or implementation described here, but that it encompasses all of them.

variants.

Claims (5)

  1 - Method of protecting and fixing prefabricated refractory parts, fixed to the walls of boiler combustion chambers using   of hooking elements, characterized in that it consists, on the one hand, in protecting the hooking element (10, 10 ', 10 ") with a layer of fractional re5 product ( 14), and, on the other hand, to ensure the connection between the refractory piece (16) and the corresponding hooking element using the same refractory product.   2 - Method according to claim 1, characterized in that said product   refractory is chemically or hydraulically bonded.   3 - Method according to one of claims 1 or 2, characterized in that   said refractory product contains silicon carbide.   4 - Process according to any one of the preceding claims, characterized in that the attachment element and its housing in the room are given   refractory an appropriate shape improving fixation.   5 - Method according to any one of the preceding claims, characterized in that all the free spaces between the walls (12) of the boiler,   the hooking elements (10, 10 ', 10 ") and the refractory pieces (16) are filled with said bonding product.