Steam boiler. RU patent 2507444.

FIELD: power engineering.

SUBSTANCE: steam boiler comprises a bottom and a roof, and also walls stretching vertically between the bottom and the roof, thus creating a reaction chamber of a steam boiler, walls of the reaction chamber include a structure comprising steam boiler pipes, besides, the steam boiler comprises in its lower part at least one section of the wall narrowing towards the bottom. The first group of steam pipes in the specified narrowing section of the wall is arranged as capable of stretching from the plane (Y-Z) of the wall into the reaction chamber and stretching from the plane (Y-Z) of the wall to the bottom of the steam boiler at the side of the reaction chamber, creating a wall in the reaction chamber, and the second group of steam pipes is made as capable of stretching towards the bottom along the plane (Y-Z) of the wall.

EFFECT: quite even heat exchange with each steam pipe in a zone of a reaction chamber.

12 cl, 2 dwg

The present invention relates to the steam boiler in accordance with the restrictive part 1.

Reaction chamber once through steam boiler circulating fluidised bed usually contains an internal part that has a rectangular horizontal cross section and is formed by four side walls, bottoms and a roof, which material inner parts, containing solid particles and, for example, fuel at the expense of gas for fluidization, usually at the expense of the supplied through the bottom of the oxygen-containing primary gas needed in the exothermic reactions occurring in the reaction chamber. The inner part, i.e. the reaction chamber, usually called the furnace chamber and boiler is called a fluidized-bed boiler, when the burning process is uniflow steam boiler fluidized bed. Usually the side walls of the furnace chamber also contain pipes, at least, fuel and secondary air.

The side walls of the furnace chamber is usually performed in such a way that they contained a panel consisting of the pipes and plates between them, resulting in the energy released by chemical reactions fuel, is used to evaporate the water running in the pipes. Surface overheating often used uniflow steam boiler with a circulating fluidized-bed for an additional increase in energy content, the pair.

When the goal is to manufacture high-power boiler, for example, the boiler with thermal capacity of several hundred megawatts, requires a large amount of the reaction mixture and much evaporation and surface overheating. From the prior art known to the location of the heat transfer areas on the side walls of the boiler, passing into the combustion chamber to increase the evaporation zone and overheating. For example, in the US 4442796 disclosed such surfaces which are located in the furnace. Also in EP 0653588 B1 disclosed wall heat transfer, arranged jointly with the side walls of the boiler and the passing into the combustion chamber.

Panel heat transfer, passing the walls of the combustion chamber burner, known from US 2009/0084293 A1, and the panel contains a couple of walls, where the two walls contain evaporative tube, facing each other. Here only one side of each wall directly subjected to the action of the furnace chamber.

Base area of the boiler is determined on the basis of the required amount and speed of gas for fluidization directly proportional to the capacity of the boiler. Usually cross section of the reaction chamber is rectangular. Its lower part is made with the possibility of narrowing to a lattice, so that one set of side walls of the reaction chamber is tilted, and a different set of lateral walls of a direct and passes to the grid. Here the straight side walls, passing to a lattice, also called end-walls in this context, narrowed like a wedge to a lattice, so that their edges meet with plots inclined lateral walls. It is used in the reaction chambers with a rectangular cross-section. Reaction chambers in the boiler with the forms of the cross-section other than rectangular forms, also known from the prior art, and such reactionary camera really often, however, have such a flat wall, the lower part of which taper to a lattice.

The location of boiler tubes on the plane of the wall on the tapered section of the wall is probably a problem if the narrowing is big enough. It is important for reliable operation once through steam boiler circulating fluidised bed to heat transfer taking place on the surfaces of boiler tubes, was sufficiently uniform in different parts of the walls of the combustion chamber. This actually means that once through steam boiler adversely, if the heat transfer surface in different parts of the furnace chamber subjected to the influence of different layer and heat respectively, depending on the structure at the bottom of the grille and furnace chamber and process control. Usually in the known solutions of the pipe length in the converging section, or, at least, the pipe sections that remain inside the furnace chamber, may differ in various parts of the walls.

In the US 7516719 B2 disclosed to the design of the bottom section of the end walls of uniflow steam boiler, and the purpose of this construction is to reduce the changing of heat exchange tubes of a steam boiler in the narrowing of the lower section and, thus, ensure as far as possible the uniform and comparable heat transfer in each of parallel pipes. This document proposes a reduction of the diameter of the pipe and plate between the pipes in the converging section instead of changing the length of the pipe. In addition, in accordance with the document, various pipes are made with the same sufficient length that aligns heat exchange to which they are exposed.

This method changes the size of the pipe and the width of the plate in the field of wall requires a lot of welding works, which increases the number of stages of work and risk of leakage.

One object of the present invention thus the creation of a steam boiler, construction of the lower part of which makes possible the creation of a high-power boiler and a large size, which is better than the previous.

The specific objective of this invention is to create the steam boiler circulating fluidised bed, construction of the lower part of which makes possible the creation of a high-power boiler and a large size, which is better than the previous.

The task of the present invention achieved by means of a steam boiler containing the floor and the roof and ceiling and walls, going vertically between the bottom and roof, thus forming a reaction chamber of a steam boiler; wall reaction chamber include construction, comprising pipes of the steam generator and steam generator contains in its lower part at least one section of the wall, narrowing to the bottom. Mostly the present invention differs in that the first group of steam pipes in the mentioned tapered section of the wall is made with the possibility of passing from the plane of the wall to the reaction chamber and the passage from the plane of the wall to the bottom of the steam boiler on the side of the reaction chamber, forming a wall in the reaction chamber, and the second group of steam pipes made with the possibility of passing to the bottom along the plane of the wall.

By this method, the solution provided with a steam boiler, the design of the end walls of which, containing steam pipes, narrowed to the bottom, and the design is predominant in terms of the production of steam. In particular, by this method, the solution provided once-through steam boiler, the design of the end walls of which, containing steam pipes, narrowed to the bottom, thus, providing a fairly uniform heat exchange with each steam pipe in the design, and the design is predominant in terms of direct-flow boiler.

The mentioned section of the wall contains, according to one embodiment of the present invention partition wall, that narrows symmetrically to the bottom relative to the Central axis of the section of the wall, in this section of the wall of the first group of steam pipes contains steam pipes on both sides of the middle axis.

In accordance with one preferred embodiment of the present invention of the steam pipes are referred to the first group are in two different subgroups at a distance from each other, so they essentially are facing each other on the same side. Therefore, one party referred to the first group of steam pipes, contained in the wall, is, essentially, free of thermal flow of the reaction chamber, so their status corresponds, in essence, as the second group of steam pipes. This is particularly advantageous in respect of the direct-flow boiler.

According to one embodiment, referred to different subgroups of the first group of steam pipes are in the wall in different planes, which are located at a distance from each other, to the bottom of the boiler. In addition, another advantage is that the distance between the first subgroup and the second subgroup is such that between them formed space, and the space is also observed in isolation from the reaction chamber.

In accordance with one variant of implementation of the elements of supply are located in the above-mentioned space to supply the reaction chamber through space, and/or referred to the space contains one or more sensors to determine the conditions existing in the reaction chamber. Elements of filing preferably located to serve gas.

Preferably steam pipes, and the first group second group are to take essentially the same thermal stream from the reaction chamber. In addition, the steam boiler is preferably once-through steam boiler.

In accordance with one variant of implementation of the steam pipe of the first group and the second group have, accordingly, is of the same length, making the size of the wall from the plane of the end wall preferably defined number of pipes in the first group.

In accordance with one's preferred option of the implementation of the first group of steam pipes passes from the plane of the end of the wall to the bottom of the steam boiler on one side of the reaction chamber held, at least part of the distance, angle, rejected from the right angle relative to the plane, and a wall upper surface is tilted in the reaction chamber.

In accordance with one variant of implementation of the first and the second groups of steam pipes are connected to a common switchgear substances, which must evaporate.

Steam boiler in accordance with the present invention is preferably once-through steam boiler with a circulating fluidized bed, made with the possibility of an exothermic reaction in circulating fluidized bed, supported by his reaction chamber. Wall reaction chamber once through steam boiler circulating fluidised bed contain steam pipes.

In addition, at least, the wall of the lower part of the reaction chamber and particularly referred to at least one section of the wall, the lower part of which is narrowed to the bottom and wall formed in it, preferably covered with fire resistant material on their side facing the reaction chamber.

Other additional distinctive features of the present invention disclosed in the accompanying claims and the following description of options for the implementation shown on the drawings.

Below will be explained to the present invention, and its work with reference to the attached schematic drawings, in which

1 schematically shows one way of implementing once through steam boiler circulating fluidised bed in accordance with the present invention, and

figure 2 depicts the construction of the pipe in the lower section of the end walls of once through steam boiler circulating fluidised bed in figure 1.

1 schematically represents one way of implementing the steam boiler 10 in accordance with the present invention; type of this boiler is the once-through steam boiler with circulating fluidized bed. Steam boiler 10 contains bottom 12 and the roof of 16 and 14 wall, passing between them. In addition, it is clear that once-through steam boiler with circulating fluidized bed contains a number of such parts and elements, which are not shown here for clarity. The bottom of the roof and the walls of 14 form a reaction chamber 20, which in the case of a boiler is burner. Bottom 12 also includes a lattice 25, through which, for example, gas for fluidization is fed into the reaction chamber. In addition, the reaction chamber with a fluidized bed contains separator 18 solids, which is typically the cyclone separator. Separator 18 of solid particles is connected with the reaction of the camera in the upper part, in the surroundings of the roof sections by means of a connecting channel 22, through which can be a mixture of chemically active gas and solid particles in the separator 18 solids. In particulate solids are separated from the gas and returned to the reaction chamber 20, i.e. in the combustion chamber after the optional processing such as cooling. For this purpose separator solid particles is connected with the bottom part of the reaction chamber 20 using channel 24 return. Gas, which were separated solids excreted from the system for further processing through the hole 26 for release of gas.

Two opposing side walls 14.1 and 14.2 of the reaction chamber 20 are to be inclined at the bottom of the direct-flow of steam boiler circulating fluidised bed, so that the side walls are approaching each other when passing closer to the bottom of the 12. Here reaction chamber 20 has a rectangular cross-section, resulting in the side walls of the established limit walls, of which only one 14.3 shown in this document. The lower section 14.31 end walls narrowed at the approach to the bottom of the 12. Leaf walls contain pipe 30 steam boiler, preferably located so that thermal load of the reaction chamber, where they all are exposed to, is, essentially, the same accordingly. Figure 2 schematically shows the lower section 14.31 end wall, with regard to the design boiler tubes. It should be noted that the pipes are drawing to simplify depicted using lines and plates, which actually connect pipes, are denoted by the distance between lines.

The lower section 14.31 end walls contain narrowing section 14.33, which is connected to an inclined section of the side walls. Steam pipes are the first group 30.1 (figure 2) in the converging section 14.31 walls are to pass from the converging section of the wall to the reaction chamber 20 and the passage from the Y-Z plane of the wall (figure 2) to the bottom of the 12 steam boiler on the side of the reaction chamber 20, forming a wall of 11 in the reaction chamber 20, and steam pipes are the second group 30.2 are to go to the bottom along the Y-Z plane of the wall (figure 2). Thus, in essence, all tubes of steam boiler tapered section 14.33 subject of the reaction in the reaction chamber 20. Thus, for example, education tapered section requires neither reduce the size of the pipe, no significant reduction of the distance between the pipes.

Figure 1 tapering section 14.41 wall symmetrically narrowed relative to the average Y-axis to the bottom of the 12. In addition, wall 11 is established, essentially, in the middle of the end wall.

Each of these pipes 30.1 steam boiler first group forms preferably, essentially, a flow channel of the same length, and pipe 30.2 steam boiler of the second group. In this connection it should be borne in mind that a minor change can be also valid uniflow steam boiler. This affects the temperature of each parallel pipes/each pipe, located in the same vertical plane, and, thus, the stresses in the wall of the pipe. Actually possible difference of lengths determined during the design stage in accordance with the calculated temperature difference (for example, the temperature of a certain pipe, which differs from the average temperature) between the pipes and the temperature difference between the defined specific maximum value. The maximum value depends on permissible stresses in the wall construction.

Wall 11 preferably contains steam pipes 30.1 who are bent on both sides of the longitudinal axis Y wall. In addition, the steam pipes 30.1 bent on both sides, i.e. the first group of steam pipes 30.1, are in two different subgroups 30.1', 30.1” (figure 2) on distance X'-X” from each other. Pipes both subgroups and the wall formed by them, are in connection with the reactionary camera 20 on one side, and there is no connection on the other side. Preferably the first group and the second group of steam pipes facing each other on the same side. In fact, the first group and the second group of steam pipes form a gas-tight wall or panel. Consequently, also the first group of steam pipes 30.1 passing through the wall of 11, is exposed to the impact of such a heat flow, and the second group of steam pipes 30.2, which runs in the Y-Z plane end wall of the reaction chamber. Preferably steam boiler in accordance with the present invention is a once-through steam boiler with a circulating fluidized bed, resulting in the work of the direct-flow boiler circulating fluidised bed due to the above characteristic better than before.

Distance X-X” between the pipes of the first group 30.1' and pipes of the second group 30.1 preferred is such that the space of 32, separated from the reaction chamber 20, is located between them. Space offers the possibility to arrange elements of 36 submission of environment, in cooperation with the wall 11, resulting in the submission of the environment through space in the reaction chamber can end up closer to the center of the reaction chamber 20. Distance X'-X” can be changed within certain limits. If in one embodiment, especially distance X'-X” is more than diameter of two steam pipes and width of the plate between them, roof space 32 formed from at least one of the steam pipes in the first group. When choosing a distance that should still be longer, the roof can be formed by more than one parallel steam pipe.

In addition, one or more sensors 38 can be located in the space of 32 to measure the conditions existing in the reaction chamber. Thus, the measured values were obtained closer to the center of the reaction chamber 20, that often gives a more realistic picture of the process.

Preferably steam pipes 30.1 first group form in the wall of the two parallel flat construction in different planes Y-X'Y X” (figure 2). The wall is preferable to vertical in the plane Y-X, resulting in the abrasive action of the flow of solid particles in the reaction chamber with a circulating fluidized bed reduced.

The pipes in the wall together preferably with the assistance of lamellar structure. In addition, wall 11 preferably covered with fire resistant material on the surface directed to the reaction chamber 20 manner known, in fact.

Wall 11 preferably perpendicular with respect to the plane Y-Z end wall 14.3 and parallel to the longitudinal axis Y end wall.

Figure 2 additionally shows that the pipe on the top surface of the wall tilted. Preferably also valid upper surface 11.1 covered with wall is leaning. Oblique top surface reduces, for example, abrasive action of solid particles moving in the reaction chamber 20 at the time of its operation (once through steam boiler circulating fluidised bed). Oblique top surface contains material for coating. In the wall of the 11 steam pipes are the first group 30.1 pass from the Y-Z plane of a wall in the reaction chamber 20 and further to the bottom of the 12 steam boiler, passing, at least part of the distance, angle, rejected from the right angle relative to the Y-Z plane, forming a wall of 11, the upper surface of 11.1 inclined in the reaction chamber 20.

Steam connection can be established, for instance, so that the first group of 30.1 and second 30.2 steam pipes are connected to a common switchgear 34 for the evaporation of a substance.

It should be noted that only a few of the most preferred options for the implementation of the present invention described above. For example, the shape of the cross section of the boiler could also be another unlike rectangular. Thus, it is clear that the present invention is not limited by the above variants of implementation and can be used in many ways. Signs described together with the different variants of implementation can be used for other implementation options, and/or various combinations of the described characteristics can be performed in the framework of the main ideas of the present invention, optional, and if it is technically possible.

1. Steam boiler (10), containing the bottom (12) and the roof (16), as well as wall (14), held vertically between the bottom and roof, thus forming a reaction chamber (20) a steam boiler, wall (14) of the reaction chamber include construction, comprising tubes (30) steam boiler, steam boiler (10) contains in its lower part at least one narrowing section 14.31) wall narrowing to the bottom (12), wherein the first group (30.1) of steam pipes in the mentioned tapered section (14.31) walls made extends from the plane (Y-Z) wall of the reaction chamber (20) and extends from the plane (Y-Z) wall to the bottom (12) a steam boiler on the side of the reaction chamber (20), forming a wall (11) the reaction chamber (20), and the second group (30.2) steam pipes made passing along the bottom of the plane (Y-Z) wall.

2. Steam boiler according to claim 1, characterized in that the narrowing section (14.31) wall contains a section of the wall, which symmetrically narrows towards the bottom, on its Central axis (Y), and the first group of steam pipes contains steam pipes on both sides of the middle axis.

3. Steam boiler according to claim 1 or 2, wherein the steam pipes (30.1) of the first group are in two different subgroups (30.1'; 30.1") at a distance from each other, so they essentially are facing each other on the same side.

4. Steam boiler of claim 3, wherein the steam pipes (30.1) of the first group are in different planes (Y-X'Y-X") at a distance from each other to the bottom (12) a steam boiler.

5. Steam boiler of claim 3, wherein the distance between the first subgroup (30.1') and the second subgroup (30.1) is such that the space (32), separated from the reaction chamber (20), are located between them.

6. Steam boiler according to claim 1, wherein the steam pipe of the first group (30.1) and the second group (30.2) are to receive is essentially the same heat flux, respectively, from the reaction chamber (20).

7. Steam boiler of claim 6, wherein, respectively, steam pipes of the first group (30.1) and the second group (30.2) have essentially the same length.

8. Steam boiler of claim 5, wherein the elements (36) the filing of the environment are in the above-mentioned space (32) to supply the reaction chamber through space.

9. Steam boiler of claim 5, wherein the one or more sensors (38) are located in the above-mentioned space (32) to measure the conditions existing in the reaction chamber.

10. Steam boiler according to claim 1, wherein the first group (30.1) and the second group (30.2) steam pipes are connected to a common switchgear (34) for the evaporation of a substance.

11. Steam boiler according to claim 1, wherein the first group (30.1) steam pipe runs from the plane (Y-Z) wall to the bottom (12) a steam boiler on the side of the reaction chamber (20), passing, at least part of the distance, angle, rejected from the right angle relative to the plane (Y-Z), forming a wall (11), the upper surface (11.1) inclined, in the reaction chamber (20).

12. Steam boiler according to claim 1, wherein the steam boiler is a once-through steam boiler with circulating fluidized bed.