DE69906120T2 - LINING AND METHOD FOR LINING A WALL OF A DEVICE FOR TERMINAL TREATMENT, MOLDED STONE AND ANCHORING THEREFOR - Google Patents

Abstract

The invention concerns a covering and a method for lining a furnace wall, as well as the corresponding anchoring element (1) and brick (2). The covering comprises prefabricated refractory anchors (1) fixed in the wall, at least two monolithic refractory masses (3) fixed on the wall by means of the anchoring elements and at least a prefabricated refractory brick (2) arranged between at least two anchoring elements and separating two of the refractory masses, said brick being maintained on the wall by the masses which it separates. The invention is applicable to boilers for incinerating domestic and industrial waste.

Description

The present invention relates to a lining and a method for lining a wall of a thermal appliance, as well as a brick and a corresponding anchoring. The thermal appliance concerned can in particular be a furnace, a boiler or a combustion chamber (FR 2 495 284 A).

It is particularly used in the field of boilers whose walls are equipped with tube panels comprising tubes connected to one another by fins, such as incinerators with grates or with fluidized beds.

Such combustion boilers are designed to recover the heat of combustion of household and industrial waste through the fluid circulating in the pipes in order to use this energy either in the form of hot water for heating collective buildings or, with the addition of a turbo-alternator, to produce electricity.

However, in order to protect the tube panels, which are subject to various combined forces: thermal, mechanical and various chemical attacks, they must be protected by a refractory wall, which thus makes it possible to ensure protection of the steel tubes of the boiler. It is also essential to insulate them so that the thermal stress developed by the combustion of the waste is not recovered too quickly by the fluids circulating in the boiler.

The protection of the boiler tube panels is mandatory and is linked in particular to the need to achieve a minimum temperature of 850ºC in the combustion gases for a minimum of two seconds between the last secondary air supply and the unprotected area of the boiler tubes, this time being necessary for the destruction of dioxins which are toxic to humans.

There are linings made of refractory concrete types whose refractory steel anchors are welded directly either to the tubes or to the ribs. These linings use a large number of anchors. The stud-based ones (anchors welded to the tubes), for example, use between 500 and 700 studs per m², while the carp-tail type anchors welded to the ribs use 60 to 80 anchors per m². Replacing the panels for maintenance becomes very difficult due to the presence of these numerous anchors.

On the other hand, lining by pouring refractory concrete is extremely time-consuming because each panel is made in situ, one after the other, in order to perfectly delimit its surface.

Other systems, made only with prefabricated refractory bricks suspended by steel anchors welded to the ribs, are used to protect the boiler walls. However, the precision of the centre distances between these suspensions is such that these centre distances define a clearance between the bricks that must be uniform and that requires very precise assembly, since the overall protection of the boiler walls depends on it. In fact, any irregularity in the clearance risks damaging the seals. and therefore impair the sealing against gases and chemical corrosion.

European patent EP-B2 080444 discloses a furnace with sheet metal wall lining comprising a cast refractory coating secured by steel anchors cast into prefabricated refractory ceramic anchoring elements. These anchoring elements are formed in a refractory monolithic mass and are secured to the wall of the furnace by bolts passing through them. This technique allows old coatings to be easily replaced for maintenance. However, it has the disadvantage of having a limited field of application and is particularly unsuitable for coating tube panels.

The present invention relates to a lining coating of a wall of a thermal device, which allows easy and quick dismantling, including on pipe panels.

The lining coating of the invention thus forms a continuous protection unit for pipes of pipe panels, allowing easy replacement of coating panels covering the walls.

Further possible advantages of the invention are:

- intimate contact between the lining coating and the boiler pipes,

- a smooth and solid surface on the combustion chamber side,

- adaptation to the curves of the wall,

- a good temporal holding of the anchors,

- a coating that is impermeable to gases and chemical corrosion .

The invention also relates to a method of lining a wall of a thermal device, which makes it possible to obtain a lining with the above advantages. The method of the invention can make it possible to carry out, in one go and continuously, the protection of a wall of a thermal device, including a wall made of tubular panels. This method allows for a quick and simple implementation.

The invention also aims at a refractory brick and a refractory anchor specifically adapted to the lining and to the lining method of the invention.

For this purpose, the invention has the object of providing a lining coating for a wall of a thermal device which:

- prefabricated fireproof anchors fixed to the wall,

- a monolithic refractory mass fixed to the wall by means of anchoring means.

The lining includes:

- at least one refractory prefabricated brick placed on the wall between at least two anchors, and

- at least a second monolithic refractory mass, each of the masses being fixed to the wall by at least one of the anchors and being separated from one of the adjacent masses by one of the bricks, the brick being held to the wall by masses adjacent to that brick.

The wall of the thermal device may consist of any surface, such as a flat left surface or the surface of a tube bundle consisting of an alternating sequence of tubes and fins connecting the tubes. The lining coating is preferably inserted between a heat source, such as a combustion firebox, and the wall.

A "monolithic" mass is a mass that is applied in situ to the wall and not pre-formed. This application can be carried out by pouring, spraying or tamping.

The special feature of refractory bricks is that they are held to the wall by the mass itself after hardening. They therefore do not need any means of fastening to the wall. They have the task of delimiting several refractory masses, each of which is held by one or more anchors.

The lining coating of the invention is specified in comparison with the prior art by the combined use of three types of elements: the anchors, the bricks and the monolithic masses. In particular, the coating of the invention introduces, in comparison with patent EP-B2 080 444, the presence of refractory bricks that can take the shapes of the wall, such as the tubular shapes, and perform the task of separating the refractory masses, while the anchors perform the task of fixing these masses.

Since the wall is a surface of a bundle of tubes consisting of an alternation of tubes and ribs connecting the tubes, each of the bricks preferably covers at least partially at least one of the tubes by taking the shape of this tube. This design allows in particular to have a very small clearance between the bricks and the tube bundle, which allows sealing of the system against gases and chemical corrosion.

Each of the anchors is preferably attached to one of the ribs. This makes assembly easier.

In a particular embodiment in which the tube bundle consists of adjacent tube walls, the coating also advantageously consists of coating plates, each plate being covered by at least one of the plates. It is interesting that each of the tube plates is covered by a sequence of adjacent plates. Preferably, these plates are identical and offset from one plate to the adjacent plate.

Advantageously, at least two bricks each have two complementary lateral faces arranged side by side on the wall, thus forming a buffer zone between two unconnected parts of the coating. A free space is usefully provided between these two bricks to allow superficial expansion between the corresponding parts of the coating. This embodiment makes it possible in particular to separate the lining into lining panels of desired lengths.

The lining preferably comprises flexible gaskets placed on the bricks, between the bricks and the adjacent refractory masses. Such gaskets compensate for the expansion of the monolithic masses. They are advantageously pre-glued and elastic at high temperatures and have a thickness that depends on the quality of the adjacent refractory masses.

The bricks preferably have a cross-section that decreases overall the further away from the wall it is. The reduction extends in the width direction, the cross-section may remain constant in one or more parts of the brick. In addition, the space delimited by the contour of the cross-section of the bricks must be taken into account, even if certain parts of the brick are hollow due to the projections of the wall, which are due, for example, to the pipes. In addition, lower parts of the brick may be cut off at the level of such projections of the wall, the overall decreasing characteristic of the cross-section nevertheless remaining.

It is advantageous that the lining comprises a refractory plaster with low mechanical strength, applied to the surface of the wall and the anchors at least in contact zones between the refractory masses. This plaster allows better dismantling of the lining coating during repair. Preferably, the plaster has the same thermal properties as the monolithic refractory masses.

Preferably, the lining coating is obtained by pouring the refractory masses into a formwork comprising an upper surface. This upper surface of the formwork delimits an external surface of the coating, which is opposite to the wall. The formwork, which serves as a mould for the refractory masses, also allows the bricks to be held to the wall by pressure and is removed after the refractory masses have hardened. It allows the surface of the coating to be shaped to be smooth and solid.

The formwork allows in particular the realization of arches. It also allows to obtain an external surface of the lining that follows the profile of the wall. In this case, the formwork is preferably made of flexible materials. The formwork makes It is also possible to introduce curvatures in relation to the wall into the outer surface of the lining.

According to a preferred embodiment based on the use of a formwork, at least one of the anchors serves as a removable support for fixing a formwork for pouring the masses onto the wall. These anchors have a dual function: holding the refractory masses and temporarily fixing the upper surface of the formwork.

At least one of these anchors preferably has a cross-section which increases overall from the wall to an external surface of the anchor, the lining comprising means for removably fixing the formwork to the anchor which pass through or line this external surface.

The "cross-section" of the anchorage means the zone delimited by the contour of the cross-section of the anchorage. The increase is understood here in the width direction, the cross-section being constant in one or more parts of the anchorage. The fastening means "crossing the external surface of the anchorage" are means based on penetration of the anchorage, such as a threaded hole interacting with a screw. The fastening means "bordering the external surface of the anchorage" are fastening means on the lateral walls of the anchorage.

In a particular embodiment using anchors that have a dual function of fixing the refractory masses and the formwork, the anchors have different lengths depending on their position on the wall and the refractory masses have a variable thickness that corresponds to the lengths of the anchors. This embodiment corresponds to the use of a flexible formwork whose upper surface follows the desired contours, which do not follow the contours of the wall.

According to another embodiment of the lining obtained by casting the refractory masses in a formwork, this lining comprises means for fixing shafts to the wall which pass through the refractory masses and allow a removable fixing of a formwork for casting these masses to the wall. Another embodiment combines the use of removable fixing shafts and anchors which serve as supports and/or fixing of the formwork.

It is advantageous that the lining comprises at least one removable fastening part of at least one of the anchors, which is firmly connected to the wall. This means that the anchors can be very easily installed for the production of the coating or removed during dismantling for maintenance.

The anchors are preferably made of steel and/or refractory ceramic.

In a preferred embodiment, at least one of the anchors comprises:

- a metallic part, preferably made of steel, which is fixed to the wall and extends into the refractory mass associated with this anchorage up to a first distance from the wall, and

- a ceramic part held by the metallic part extending into said mass to a second distance of the wall which is greater than the first distance, the ceramic part preferably extends to the outer surface of the mass.

Such anchors make it possible to achieve a compromise between steel and ceramic. Steel anchors have the disadvantage of deteriorating over time, particularly under the action of substances resulting from waste incineration, but they allow good fastening to the wall. In the above anchors, the steel part for fastening to the wall is present, but it can be sufficiently low compared to the external surface of the lining to be protected and thus offer better holding over time.

In a first embodiment of such an anchor, the steel part penetrates into the interior of the ceramic part. In a second embodiment, the ceramic part comprises notches into which ends of the metal part are inserted.

According to an advantageous embodiment, the refractory masses consist of refractory concrete. In an embodiment, which is particularly interesting in the presence of acidic gases or flue gases, the refractory masses consist of refractory plastic masses.

The invention also relates to a prefabricated refractory brick for lining a wall of a thermal appliance. According to the invention, the brick has a shape that allows this brick to be held on the wall by hardening of at least one monolithic refractory mass.

This definition excludes in particular any paralelepiped brick.

Preferably, the brick according to the invention is such that it corresponds to one or more of the embodiments of the coating according to the invention. In particular, the brick preferably has:

- a shape that partially takes the form of a tube and/or

- a cross-section that decreases globally from one surface to the opposite surface of the brick.

The invention also relates to a prefabricated fireproof anchor for lining a wall of a thermal device. According to the invention, the anchor serves as a removable fastening support for a formwork.

Compared to known anchors, the anchor according to the invention has a shape that allows it to serve as a support and is provided with specific fastening means.

Preferably, the anchor according to the invention is suitable for one or more embodiments of the lining according to the invention. In particular, it is advantageous for the anchor to have a cross-section that increases globally from the base intended for attachment to the wall and up to an external surface of these anchors and to be equipped with removable means of fastening a casing to the anchor that pass through or line this external surface.

The invention also relates to a method for lining a wall of a thermal device, in which:

prefabricated fireproof anchors are attached to the wall and

- a fireproof mass is placed on the wall and secured with anchors.

After the invention:

- before applying the refractory mass, at least one prefabricated refractory brick is placed on the wall between at least two anchors, and

- at least a second refractory mass is placed on the wall, each of these masses being fixed to the wall by at least one of the anchors, and two of these masses being poured on one side and the other of this brick and holding this brick to the wall after hardening.

The lining method according to the invention preferably allows the production of a lining coating according to one or more of the embodiments of the invention.

The invention will be more easily understood by means of particular embodiments presented with reference to the accompanying figures, in which:

Fig. 1 shows in section I-I a partial cross-section of a pipe sheet covered with a lining coating according to the invention;

Fig. 2 shows in front view the tube sheet and the lining coating of Fig. 1;

Fig. 3 shows in detail a first embodiment of an anchoring of the coating shown in Figs. 1 and 2 with the attachment of a formwork on the lining;

Fig. 4 shows in detail a second embodiment of an anchoring of the lining shown in Figs. 1 and 2 with attachment of a formwork on the coating;

Fig. 5 shows in detail refractory bricks of the lining of Figs. 1 and 2;

Fig. 6 shows in front view two adjacent tube sheets, each covered with a lining coating according to the invention similar to that shown in Figs. 1 to 5;

Fig. 7 shows a third embodiment of an anchor according to the invention in side view;

Fig. 8 shows a section VIII-VIII of the third embodiment of an anchorage according to Fig. 7;

Fig. 9 shows a fourth embodiment of an anchor according to the invention;

Fig. 10 illustrates another embodiment of a liner coating of a pipe sheet comprising the anchors of the third and fourth embodiment of Figs. 7 to 9 and fastening shafts;

Fig. 11 shows in partial section XI-XI the pipe panel with lining of Fig. 10 covered with a formwork;

Fig. 12 shows in partial section XII-XII a pipe sheet with another embodiment of a lining coating according to the invention

Fig. 13 shows in front view the tube sheet covered with the lining coating of Fig. 12;

Fig. 14 shows in front view two adjacent pipe panels with lining coatings similar to those in Figs. 12 and 13.

In the following, the technical teaching of the figures must be considered as supplementary to the technical teaching of the description.

Identical or similar elements of different embodiments are designated by the same reference numerals. In addition, similar elements are generally specified with the suffixes A to E that complement the reference numerals. The suffixes A to D respectively refer to four embodiments of the anchors and the suffixes A and E refer to two embodiments of the bricks. In addition, in the first embodiment of the bricks, the suffixes A and A' respectively apply to complementary bricks that form pairs.

A tube panel consisting of tubes 14 interconnected by welded ribs 4 forms a wall 16 facing a thermal firebox (Figs. 1 and 2). Fluids such as water circulate inside the tubes 14. A lining coating covering the tube wall comprises prefabricated refractory anchors 1, prefabricated refractory bricks 2 and monolithic refractory masses 3 of refractory concrete cast in situ. The lining coating is distributed in lining panels 20 arranged side by side along the panel at right angles to the direction the pipes 14 are arranged in a sequence of plates 20j-1, 20j and 20j+1 separated from the seals 18. The seals 18 are, for example, 3 mm wide. Each lining plate 20 is rectangular and has, for example, sides with a length of 700 mm.

In a first embodiment of the anchors 1, with the reference 1A and shown in Fig. 3, the anchor 1A comprises a steel part 31A and a ceramic part 32A. The steel part 31A comprises a threaded arm 35A and a connecting part 15A of approximately frustoconical and hollow shape, having a vertex integral with the threaded arm 35A. The connecting part 15A is incorporated in the ceramic part 32A. The latter forms a solid anchor head of approximately frustoconical shape, with a small base 39A at the level of the threaded arm 35A and a large base forming a flat outer surface 36A of the anchor 1A beyond the connecting part 15A. The outer surface 36A is spaced from the connecting part 15A by a distance dA sufficient to protect the metal part 31A from harmful seepage from the outer surface 36A. The threaded arm 35A is fixed to the wall 16 by a fixing part 5 welded to one of the ribs 4. This fixing part 5, for example of the type of a nut, comprises an internal thread for screwing the threaded arm 35A.

Since the anchor rotates approximately about an axis 70A, the ceramic part 32A is provided with a blind hole 37A arranged along the axis 70A of the anchor 1A starting from the external surface 36A. This blind hole 37A is intended to receive a fixing dowel 10A for the insertion of a fixing screw 9A.

In another embodiment of the anchorage 1, shown in Fig. 4 and designated 1B, the same or similar Elements as in the anchor 1A have the same reference numerals with the suffix B in place of A. The anchor 1B differs from the anchor 1A in that the blind hole 37B extends approximately to the top of the connecting part 15B, the fixing plug 10B being intended to contain a threaded shaft 13 which projects from the external surface 36B so as to be able to receive a nut 38.

In the present embodiment, the bricks 2 are provided in pairs, each pair comprising two bricks 2, each with the references 2A and 2A' (Fig. 5). The bricks 2A and 2A' each have first faces 43 and 44 of complementary shape, intended to be arranged side by side transversely to the wall 16. These first faces 43 and 44 are preferably flat and, more precisely, advantageously arranged parallel to a median plane 71 between the two faces 43 and 44, which is at right angles to the wall 16. The bricks 2A and 2A' also comprise second faces 45 and 46, which have a shape that conforms to the contour of two pipes 14, respectively, located adjacent to these faces 45 and 46. They also comprise third faces 47 and 48, respectively, opposite to first faces 43 and 44 and comprising an oblique part 17 which creates a narrowing of the bricks 2A and 2A' as it moves away from the two faces 45 and 46. The third faces 47 and 48 are extended by fourth faces 49 and 50, which are approximately parallel to the first faces 43 and 44. The bricks 2A and 2A' also comprise fifth faces 51 and 52, respectively opposite to second faces 45 and 46 and which are preferably flat. The first faces 43 and 44 and the fifth faces 51 and 52 are cut off at their intersection so as to form sixth faces 53 and 54 in chamfered form.

Preferably, the bricks 2A and 2A' are identical and arranged symmetrically with respect to the plane 71.

Flexible seals 11 are pre-glued onto the fourth surfaces 49 and 50 of the bricks 2A and 2A'. These seals 11 are preferably made of refractory materials that remain elastic at high temperatures and are intended to compensate for expansion of the panels 20.

To produce the lining coating according to a first embodiment as described above, the following procedure is followed. First, the fastening parts 5 are welded onto a part of the ribs 4 of the pipe sheet to be lined. The fastening parts 5 are evenly distributed within each part of the wall 16 to be covered by one of the lining panels 20 (Fig. 2). They preferably form a network of parallel lines at right angles to the pipes 14. At right angles to the pipes 14, they are welded, for example, onto every second rib (Figs. 1 and 2).

Then, using a brush, a refractory plaster with low mechanical strength, preferably having the same thermal properties as the refractory concrete 3 to be applied, is applied to the tubes 14 and the ribs 4. The cement is preferably applied selectively in zones 12 intended to be in contact with the refractory concrete 3.

Then, the prefabricated anchors 1 are mounted by screwing them into the fixing parts 5. Beforehand, the threaded arm 35 of the anchors 1A or 1B is covered with a protective tube 6, such as a cardboard tube, to prevent the fireproof cardboard 3 from blocking the threaded arm 35A (Fig. 3 and 4). Using a brush, apply a thin layer of fireproof plaster to anchorages 1A or 1B in Zones 12 intended to be in contact with refractory concrete 3.

The application of the fire-resistant plaster to the anchor 1 must make it possible to unscrew this anchor 1 during dismantling.

The bricks 2 are also arranged in pairs 2A and 2A' at the level of the joints 18 provided between the lining panels 20 (Figs. 1 and 2). Each of the pairs of bricks 2A and 2A' partially covers two adjacent tubes 14 (Fig. 5), the first faces 43 and 44 of the bricks 2A and 2A' having between them a free space 56 intended to form the seal 18 between the two panels 20 each lined by two bricks 2A and 2A'. The bevels 53 and 54 delimit an upper free triangular space 55 intended to facilitate removal of the panels 20. Furthermore, the second lower surfaces 45 and 46 between the bricks 2A and 2A' and the rib 4 contained between the tubes 14 covered by the bricks 2A and 2A', leave free a lower space 57 in which, according to a particular embodiment, it is of interest to apply the refractory plaster beforehand.

A formwork 7 is then positioned over the anchors 1 and the bricks 2. This formwork 7 rests on an external face 36 of the anchors 1A and 1B and on the fifth faces 51 and 52 of the bricks 2A and 2A'. The formwork 7 is fixed to each of the anchors 1A by placing a pressure plate 8 on the formwork 7 above the anchor 1A concerned and by locking the formwork 7 by a fixing screw 9A which passes through the pressure plate 8 and the formwork 7 by inserting itself into the dowel 10A of the anchors 1A (Fig. 3).

Similarly, the formwork 7 is fixed on each of the anchors 1B with the threaded shaft 13 positioned in the dowel 10B passing through the formwork 7 and a pressure plate 8 by tightening a nut 38 above the pressure plate 8 (Fig. 4).

The pressure plates 8, for example, are washers made of steel.

The formwork 7 is sufficiently strong to hold the masses 3 of refractory concrete to be poured and is preferably made of flexible materials. It is advantageously transparent so that it is possible to visually observe the correct placement of the masses 3 of refractory concrete. In other embodiments, the formwork is made of wood or steel.

The formwork positioned and secured in this way holds the bricks 2 in position.

The masses 3 of refractory concrete are then placed in the formwork 7 by pouring. After hardening, the screws 9A, the nuts 38, the threaded shafts 13, the pressure plates 8 and the formwork 7 are removed and the external surface 26 of the lining coating is obtained, consisting of a smooth, solid surface. The dowels 10, which are not refractory, are designed to disappear under the effect of the temperature of the firebox.

In the presence of several tube sheets next to each other, separated by gaskets 19 which are, for example, 9 mm thick (Figure b), a succession of lining plates 20 and 21 is advantageously carried out for each of the tube sheets. The gaskets 18 between the lining plates of two adjacent sheets are therefore advantageously offset.

According to a third embodiment of the anchors 1, with the reference 1C and shown in Figures 7 and 8, the anchor 1C comprises a steel part 31C having a substantially hollow frustoconical shape with a small base 71 and two internal edges 73 and 74 opposite the small base 71. The anchor 1C also comprises a ceramic part 32C having a substantially solid frustoconical shape provided with two lateral notches 33 and 34. The ceramic part 32C is held on the steel part 31C by inserting the internal edges 73 and 74 into the notches 33 and 34 respectively, the ceramic part 32C having a small base 39C arranged opposite the small base 71 of the steel part 310.

The anchors 1C are fixed to the tube sheet by welding the small base 71 to one of the ribs 4. The anchor 1C retains a supporting function of the formwork 7 via the external flat surface 36C of its ceramic part 32C, but has no fixing function of the formwork 7.

A fourth embodiment of the anchorage 1 with the reference 1D, shown in Fig. 9, concerns only a part made of steel 31D and no ceramic part. The anchorage 1D, which has a roughly shell shape, is welded to one of the ribs 4 by means of a foot 75. The anchorages 1D have such dimensions that after welding they remain away from the formwork 7, i.e. from the upper surface 26 of the lining coating. These anchorages 1D thus serve exclusively to hold the refractory concrete 3 on the tube bundle.

In a particular embodiment of the lining process, in which anchors 1C and 1D are used, anchors 1C and 1D are welded alternately to the ribs 4 parallel to the tubes 14 (Figs. 10 and 11).

In addition, the formwork 7 is secured by means of threaded rods 61 extending transversely to the wall 16 and having a length sufficient to cover the distance between the wall 1b and the formwork 7 for the introduction of the refractory concrete masses 3. The rods 61 cooperate with fastening nuts 60 welded to certain ribs 4 at the level of the joints 19 between the tube panels and intended to receive threaded rods 61, and with tightening nuts 62 intended to tighten the formwork 7 by compression. For example, the fastening nuts 60, the threaded rods 61 and the tightening nuts 62 belong to the type designated by the name M 12.

To carry out the lining process, one begins by welding the fastening nuts 60 and the anchors 1C and 1D, one applies the refractory plaster as in the previous embodiments and one tightens the shafts 61 in the fastening nuts 60. The formwork 7 is then arranged resting on the anchors above the pipe panel to be lined and is fastened with the threaded shafts 61 by arranging pressure plates 8, similar to those described above, on the formwork 7 above the threaded shafts 61 and tightening the formwork 7 against the ceramic parts 32C of the anchors 1C by screwing the nuts 62 on the threaded shafts 61 against the pressure plates 8.

The refractory concrete 3 is then poured into the formwork 7 and, after it has hardened, the clamping nuts 62, the pressure plates 8, the formwork 7 and the threaded shafts 61 are removed. This produces lining panels 22 with an outer surface 26 in the form of a smooth, solid surface.

In another embodiment of the lining coating, shown in Figures 12 and 13, the bricks 2, with the reference numerals 2E, are intended to be placed directly between two masses 3 of refractory concrete, with the reference numerals 3E, and in contact with them, at right angles to the tubes 14.

Each of the bricks 2E has a lower surface 81 which at least partially conforms to the shape of one or more tubes 14, and preferably three tubes 14. The brick 2E also comprises lateral surfaces 82 and 83 which are inclined so as to result in a narrowing of the brick 2E by moving away from the lower surface 81. The lateral inclined surfaces 82 and 83 are extended by lateral surfaces 84 and 85 which are advantageously at right angles to a central plane of the lower surface 81. The lateral surfaces 84 and 85 are covered with flexible seals 11. The brick 2E also comprises an upper surface 86 which is preferably flat and parallel to this central plane. In addition, the brick 2E is preferably parallel with respect to a central plane 72 which is at right angles to this central plane.

To produce a lining coating with the bricks 2E, the procedure is similar to that of the previous embodiments, but by alternating one of the bricks 2E with one or more anchors 1 at right angles to the tubes 14. Advantageously, a single anchor 1 is arranged between two of the bricks 2E at right angles to the direction of the tubes 14.

Since the bricks 2E do not form a separation between the masses 3E of refractory concrete, a single lining plate 23 is thus obtained on the pipe panel to be lined.

In the presence of several pipe panels next to each other, each of them is covered with a lining plate 23 or 24 (Fig. 14), the rows of anchors 1 parallel to the pipes 14 preferably alternating from one lining plate to the other.

The invention covers any combination of the embodiments and applications described above, in particular the combined use of any of the anchors 1 with any of the bricks 2.

The number of anchors 1 is chosen to be sufficiently small in order to reduce the number of welds on the wall 16 to a minimum while still maintaining the correct masses 3 of refractory concrete. In general, the anchors can be relatively far apart at right angles to the direction of the pipes 14, but they must be more numerous and preferably regularly distributed parallel to the direction of the pipes 14.

Claims (21)

1. Unit formed by a lining and a wall of a thermal device, comprising - fireproof prefabricated anchors (1) fixed to the wall (16), and - a refractory monolith mass (3) fixed to the wall (16) by means of anchors (1), characterized in that the lining comprises: - at least one fireproof prefabricated brick (2) which is arranged on the wall (16) between at least two anchors (1), and - at least a second refractory monolith mass, each of the masses (3) being fixed to the wall (16) by at least one of the anchors (1) and separated from the adjacent masses (3) by one of the bricks (2), the brick (2) being held to the wall (16) by the adjacent masses (3) adjacent to the brick (2). 2. Unit according to claim 1, characterized in that the wall (16) is a surface with a tube bundle consisting of alternating tubes (14) and ribs (4) connecting the tubes (14), each of the bricks (3) at least partially covering at least one of the tubes (14) by flush enclosing the shape of the tube (14). 3. Unit according to claim 2, characterized in that each of the anchors (1) is attached to one of the ribs (4). 4. Unit according to one of claims 2 or 3, characterized in that the tube bundle consists of abutting tube panels, the lining consisting of lining plates (20-24), each of the panels being covered by at least one of the plates (20-24). 5. Unit according to one of claims 1 to 4, characterized in that at least two bricks (2A, 2A') each have two complementary side surfaces (43, 44) which are arranged side by side on the wall (16) and thus form a buffer zone (56) between two separate parts (20, 21, 22) of the lining. 6. Unit according to one of claims 1 to 5, characterized in that it comprises flexible seals (11) arranged on the bricks (2), between the bricks (2) and the adjacent refractory masses (3). 7. Unit according to one of claims 1 to b, characterized in that the bricks (2) have a cross-section which gradually becomes smaller the further away from the wall (16). 8. Unit according to one of claims 1 to 7, characterized in that it comprises a refractory plaster applied to the surface of the wall (16) and the anchors (1) at least in the contact zones (12) with the refractory masses (3). 9. Unit according to any one of claims 1 to 8, characterized in that at least one of the anchors (1A, 1B) serves as a removable fastening support for a formwork (7) for pouring the masses (3) on the wall (16). 10. Unit according to claim 9, characterized in that at least one of the anchors (3A, 3B) has a cross-section (3) that increases globally from the wall (16) and up to the external surface (36A, 36B) of the anchor (1A, 1B), and in that the lining comprises removable means for fixing (8-10, 37, 38) the formwork (7) to the anchor (1A, 1B), which pass through the external surface (36A, 36B) or are located at the edge thereof. 11. Unit according to one of claims 9 or 10, characterized in that the anchors (1) have different lengths depending on their position on the wall (16) and in that the refractory masses (3) have a variable thickness corresponding to the lengths of the anchors (1). 12. Unit according to one of claims 1 to 11, characterized in that it comprises means (60) for fixing to the wall (16) shafts (61) which pass through the masses (3) and allow a formwork (7) for pouring the masses (3) to be fixed to the wall (16) in a removable manner. 13. Unit according to one of claims 1 to 12, characterized in that it comprises at least one removable fastening part (5) for at least one of the anchors (1A, 1B) which is firmly connected to the wall (16). 14. Unit according to one of claims 1 to 13, characterized in that at least one of the anchors (1A-1C) comprises: - a metallic part (31), preferably made of steel, which is fixed to the wall (16) and which extends in the refractory mass (3) belonging to the anchors (1A-1C) up to a first distance from the wall (16), and - a ceramic part (32) held on the wall (16) by the metallic part (31) and extending into the mass (3) to a second distance from the wall which is greater than the first distance, the ceramic part (32) preferably extending to the outer surface (36) of the mass (3). 15. Unit according to one of claims 1 to 14, characterized in that the masses (3) consist of refractory concrete. 16. Refractory prefabricated brick (2) for a unit for lining a wall (16) of a thermal installation according to one of claims 1 to 15, the wall (16) comprising pipes (14), characterized in that it has a first surface (43) intended to be arranged at right angles to the wall (16) in the lining, a second surface (45) intended to enclose flush the contour of an adjacent pipe (14) in the lining, a third surface (47) opposite to the first surface (44) and forming an oblique part (17) creating a taper of the brick by moving away from the second surface (45), a fourth surface (49) extending the third surface (47) and approximately parallel to the first surface (43), and a fifth flat surface (51) facing the second surface (45) and is bluntly cut off to form a sixth surface (53) of the chamfer type. 17. Refractory prefabricated brick (2) for the lining unit of a wall (16) of a thermal installation according to one of claims 1 to 15, the wall (16) comprising tubes (14), characterized in that it comprises a lower surface (81) which at least partially encloses the shape of at least one tube (14), but preferably three tubes (14), lateral surfaces (82) and (83) which are inclined so that where they depart from the lower surface (81) they result in a taper of the brick, lateral surfaces (84) and (85), which extend the surfaces (82) and (83) and preferably at right angles to a median plane of the lower surface (81), and an upper surface (86) which is preferably flat and parallel to the median plane of the lower surface (81). 18. Brick (2) according to claim 17, characterized in that it is symmetrical to a central plane (72) which is at right angles to the central plane of the lower surface (81). 19. Refractory prefabricated anchor (1) for the lining unit of a wall (16) of a thermal installation according to one of claims 1 to 15, the wall (16) comprising tubes (14), characterized in that it comprises a steel part (31A, 31B) and a ceramic part (32A, 32B), the steel part (31A, 31B) comprising a threaded arm (35A, 35B) and a connecting part (15A, 15B) of approximately hollow conical shape, embedded in the ceramic part (32A, 32B), with a top integral with the threaded arm (35A, 35B), the ceramic part (32A, 32B) comprising a blind hole (37A, 37B) intended to accommodate a fixing dowel (10A, 10B) to be recorded. 20. A method for lining a wall (16) of a thermal device, in which: - fireproof prefabricated anchors (1) are fixed in the wall (16); and - a fireproof mass (3) is placed on the wall (16), the mass (3) is fixed with the anchors (1), characterized in that: - before applying the mass (3), at least one refractory prefabricated brick (2) is placed on the wall (16) between at least two anchors (1); and - at least a second refractory mass (3) is applied to the wall (16), each of the masses (3) being fixed to the wall (16) with at least one of the anchors (1), one mass (3) being poured on each side of the brick (3) which holds the brick (2) to the wall (16) after hardening. 21. A lining method according to claim 20, characterized in that it allows the manufacture of a unit according to one of claims 1 to 15.