FI101323B - Fireplace overheater and reactor with circulating bed with fireplace over heater - Google Patents

Abstract

The present invention relates to a furnace superheater having a number of tube elements arranged relative to each other in such a way that they form a planar surface and in which the tube elements are mechanically arranged. The superheater elements are preferably rectangular of their cross-sectional profile and they are attached to each other by means of a groove or the like and a protrusion or the like which have a substantially similar profile. The present invention also relates to a circulating bed reactor provided with a furnace superheater.

Description

101323

FIREPLACE 8LIGHTER AND ΚΙERTOPETETRACTOR WITH FIREPLACE HEATER

ELDSTAD8ÖVERHETTARE OCH REAKTOR MED CIRKULERANDE BÄDD MED ELD8TAD8ÖVERHETTARE

5

The present invention relates to a furnace superheater in which a plurality of adjacent tubular elements are mechanically attached to each other from their opposite surfaces.

The present invention also relates to a circulating bed reactor equipped with a furnace supercharger, comprising a reaction chamber, a solids separator connected thereto and a return duct connecting the solids separator to the reaction chamber, evaporator surfaces, and a steam superheater furnace 15

In a circulating bed reactor, a solid, such as fuel, inert bed material and / or limestone (combustion or gasification application), is fluidized by gas supplied via gas feeders located at the bottom of the reactor. The fluidization rate in circulating bed reactors is so high under normal conditions that a considerable portion of the solids travels with the gas out of the reactor. It is typical of the name's own circulating bed that the amount of solids carried by the gases is so large that without the recycling (or addition) of solids the operation of the bed cannot be maintained.

Thus, in a circulating bed reactor, considerable amounts of solids are transported with the gases through the top of the reactor out of the reactor. In a certain area of the reactor, both upward and downward flow of bed material takes place. Absolute mass flow.

varies both radially and axially in the reaction chamber. At the outer walls, the downward mass flow is at its maximum. As the particle density increases towards the lower part of the reaction chamber, the layer formed by the particles descending along the outer walls also thickens. Even the slightest change in the flow direction of the particles 2 101323 causes erosion. Thus, a circulating bed reactor is a very abrasive environment for various structures. Due to the abrasive nature of the rotary bed reactor, it has been proposed to use tubular elements in the furnace which, when connected to each other, create a flat outer surface. As a structure of a furnace superheater for power plant boilers based on, among other things, circulating bed technology, this has been proposed in situations where the superheater is placed directly in the furnace of a circulating bed reactor. Such pipe elements are joined to each other by welding. Welding always involves several time-consuming work steps, such as preheating, hef-tapping, pipe welding on two sides, straightening due to stresses, and welding inspection. The superheater panel formed by this method is thus quite irreversibly formed into a single structure. The welding is thus done on both sides, after which both surfaces are machined as evenly as possible. This is recommended because the circulating bed reactor, even at the tops, has such abrasive conditions that otherwise sufficient reliability cannot be guaranteed.

The formation of parallel round tubes as superheater surfaces without welding is disclosed in US 5,012,767.

In it, adjacent pipes are connected to each other by a combination of two sleeves, which sleeves are welded together. The solution is very sensitive to wear, the sleeves also form a wear discontinuity. The publication also discloses separate fastening members to be welded between the pipes. The solution is erosion sensitive and increases the distance between the pipes 30, so that fewer pipes can fit in the same space.

U.S. Pat. No. 2,809,616, SE-B-355 228, DE 2 347 444, FI-080142 and U.S. Pat. No. 5,083,372 disclose various ways of mechanically connecting conventional round tubes to panels by fastening elements. The panels are particularly prone to wear in the case of fasteners.

3 101323

The object of the present invention is to eliminate the need for welding in connection with the manufacture of furnace superheater tubes, whereby the manufacturing time of the panel structure is significantly reduced. At the same time, the work-5 steps associated with welding, such as preheating, hefta- tion, pipe-side welding on two sides, stress-induced straightening, and welding inspection, are eliminated or reduced.

It is also an object of the present invention to provide a circulating bed reactor in which furnace superheaters are formed as planar surfaces corresponding to the prevailing conditions in a very simple manner.

It is also an object of the present invention to provide a circulating bed reactor in which furnace superheaters are formed as wear-resistant structures.

The object of the present invention is therefore to eliminate the drawbacks of the prior art and to provide a completely new solution. The features of the invention, in order to achieve the above-mentioned objects, are precisely defined in the features of claims 1 and 9 below.

More specifically, for a furnace heater according to the invention, in particular in a circulating bed reactor comprising a reaction chamber, a solids separator connected thereto and a return duct connecting the solids separator to the reaction chamber, the evaporator surfaces and the steam superheater are substantially rectangular in cross-section, a groove or the like is provided on one attachment surface of adjacent tubular elements and a protrusion or the like is provided on the other attachment surface, and that the tubular elements connected to each other form a substantially planar surface.

4 101323

According to a first embodiment of the invention, the furnace supercharger, which is particularly suitable as a circulating bed reactor fire-furnace superheater, is formed in such a way that superheater tubes of rectangular cross-section are connected to each other by means of grooves or the like. In this context, the term "rectangular" means a shape comprising at least two substantially parallel sides which at least partially overlap. In this case, the fire-10 housing superheater according to the invention consists of several interconnected individual superheater tubes, which are connected to each other in the superheater tube material by means of connecting grooves or the like arranged on its connecting surface.

According to the invention, the connecting groove or the like can be made by machining or the connecting surfaces can also be formed in connection with rolling. The connecting groove or the like can be implemented in many ways. However, it is preferred that the possibility of movement of the put tongue elements relative to each other be eliminated to an appropriate extent.

According to an embodiment of the invention, the connection consists of an indentation, a groove or the like in the second tubular element and a projection in the second tubular element 25, which, when fitted together, provide a mechanical connection.

The superheater tube elements are substantially rectangular in cross-section and are interconnected by a groove or the like with substantially similar cross-sectional profiles and a protrusion or the like. By protrusion or the like is meant a body 35 which mimics groove shapes 35 fixedly or movably arranged relative to a tubular element adjacent to a grooved tubular element.

5 101323

According to the invention, the tubular element comprises a flow path forming, preferably a circular channel bounded by the pipe material so that the outer surface of the tubular element is spaced from two substantially parallel planar surfaces spaced apart by two substantially planar surfaces. substantially similar in cross-sectional profile with a connecting groove or the like 10 and / or a protrusion or the like.

The connecting groove or the like of the tubular element and the protrusion or the like are preferably shaped in the shape of a substantially parallelepiped, trapezoid, circle, semicircle, triangle or a combination thereof. Even other embodiments of the invention may be practiced if desired. The connecting groove or the like of the pipe element is preferably larger or equal in cross-section than the projection or the like.

20

The invention achieves considerable advantages over the prior art. The invention eliminates the need for welding in the longitudinal direction of the tubes of the firebox superheaters. The manufacturing time of the panel structure is significantly reduced, shortening the throughput time of the product 25. Welding-related work steps such as preheating, hefta- tion, pipe welding on two sides, stress correction and welding inspection are replaced by the solution according to the invention.

The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows by way of example a circulating bed reactor equipped with a furnace superheater according to the invention, Figure 10 shows a preferred embodiment of the furnace superheater of Figure 1, Figure 3 shows another embodiment of the invention. a preferred embodiment of the furnace superheater of Figure 1, Figures 4-6 show different cross-sectional profiles of the furnace superheater according to the invention, and Figure 7 shows another preferred embodiment of the furnace superheater according to the invention for forming the furnace superheater of Figure 1.

Figure 1 shows a circulating bed reactor 2 comprising a combination of a reaction chamber 4, a hot gas separator 6 and a return duct 8 into which fluidizing gas is introduced through one of its bottoms 10 or elsewhere (not shown) to form a circulating bed. A solid, such as a fuel, is introduced through one 12 or more (not shown) together 20. The product gases are removed from the hot gas separator together through 14. A process that produces heat is maintained in the reaction chamber. This heat is recovered e.g. through the walls 16 of the reaction chamber formed of steam-rust tubes to the evaporating boiler water. The water 25 to be evaporated is fed to the evaporator tubes from the cylinder 18 via the connections 20 and the steam / water mixture flows back to the cylinder, for example via one 22. This circuit, presented in this context, contains a great many generalizations and simplifications, in fact the circuit comprises a wide variety of 30 other components. The hot gas separator is also preferably formed of evaporator or other heat transfer surfaces. Equally, the circuit may be natural or forced for the present invention; it is suitable for both solutions. A furnace superheater 24 is arranged in the reaction chamber, here in its upper part 35, to which steam is supplied via means 26. From the superheater, the steam is led through the channel 28 to the turbine engine 30 and from there 7 101323 further back to the cylinder via the channel 32. This circuit is also very much simplified.

The furnace superheater 24 at the top of the reaction chamber 4 is adapted to superheat the steam using the heat given off by the reactor solid-gas suspension. The superheater 24 is arranged in the circulating bed reactor so that it preferably extends beyond the opposite walls of the reaction chamber at both ends. In this way, on the other hand, it can be strongly and reliably supported at its ends in the reaction chamber. On the other hand, the relatively long distance between the reactor walls places certain requirements on the stability of the panel. In use, a poorly supported structure will easily vibrate or bend as a result of possible thermal expansions. In other words, the superheater panel must be sufficiently rigid. This is arranged according to the invention by supporting the pipe elements longitudinally to each other by means of a mechanical connection. Such a mechanical connection is achieved according to the invention by always arranging in the adjacent pipe elements on the connecting surfaces suitable mating, shaped surfaces which sufficiently prevent the movement of the elements relative to each other. Connections 34 are provided at the ends of the superheater to control and / or distribute the flow of steam as desired between the individual tubular elements of the superheater 25. According to the invention, the furnace superheater is formed by mechanically connecting pipe elements to each other, whereby longitudinal welding of the pipes is not required. However, the pipe panel formed by the solution according to the invention is tightly connected to the joints 34 so that the requirements of steam production are met, preferably by welding the pipe panel to these joints.

The circulating bed reactor has very consuming conditions in the furnace: a relatively high temperature (e.g. 600-1200 ° C) combined with solid particles in the gas. Under such conditions, wear of the surfaces is very easy, especially if there are points of discontinuity on the surface. Therefore, the furnace superheater according to the invention is preferably formed of a plurality of superimposed tube panels formed of a plurality of interconnected tube elements 36, the surfaces of which are arranged substantially planar by the method according to the invention for forming a furnace superheater.

Figure 1 shows a circulating bed reactor adapted mainly for fuel combustion, but the firebox-superheater according to the invention can, of course, also be used in other types of fireboxes, if necessary, even for example. dust burning boilers. The best properties of the furnace superheater according to the invention appear precisely under the conditions in which it is surrounded by a solid gas mixture. Thus, the circulating bed reactor can also act as a hot gas cooler, for example in connection with a grate combustion plant, whereby its grate solution differs mainly from that shown. The firebox superheater according to the invention can also be placed in the firebox 20 at different levels, although it is in the upper part of the firebox in Fig. 1.

Figure 2 shows a method of forming a tube panel of a furnace superheater according to the invention. It shows two tubular elements 362, 366 connected to each other by a connecting groove 364 formed by an indentation 368 in the second tubular element 362 and a protrusion 370 in the second tubular element. These, the projection and the indentation, together form a joint which sufficiently binds the 30 elements together tulistuspaneelia. The protrusion or indentation can be arranged in the tubular elements either so that each element comprises an indentation at one end and a protrusion at the other end. Another alternative is that there are two types of tubes: tubes with alternatively either protrusions or indentations, in which case both tube types are required to form substantially the same number of tubes. The first alternative 9 101323 is therefore a more advantageous solution, since only one type of pipe element is required. Such a method is shown in Figure 3. A flow path 372 for the steam to be superheated is arranged inside the pipe element. The tubular tent is formed in accordance with the invention so as to comprise two substantially parallel and planar surfaces 374, 376 the distance between the surfaces of which is selected so as to provide a channel or flow path 372 between the surfaces and in addition sufficient material strength 10 for the channel 372 and the surfaces. to an area 378. The element resembles a rectangular cross-section in which the ends 380, 382 connecting the surfaces are formed as mounting surfaces on which a mounting groove or the like is formed. Surfaces 374 and 376 extend far enough to provide attachment surfaces with indentation or protrusion and sufficient material strength to form flow paths.

Figures 4 to 6 show different ways of forming the joint surface shapes required for the joints of the pipe elements 20. In Fig. 4, the protrusion and the indentation are formed at one end by a perpendicular surface 41 and at the other end by an oblique surface 43. In Fig. 5, on the other hand, the protrusion and the indentation are formed as approximately circular surfaces, while in Fig. 6 they are arranged in triangular form.

The method shown in Figure 7 for connecting the tube elements of the furnace superheater to each other is very advantageous. In it, indentations 72 are arranged on opposite fastening flanges of two adjacent pipe elements 70, which elements, when in parallel, form a space 74 between the pipes. The tubes are secured together by fitting into this space 74 a rod or the like substantially mimicking its shape, which thus corresponds to a protrusion or the like but is not fixedly arranged in the tube elements. This rod or the like does not necessarily have to extend integrally from end to end of the tubes, but the fastening can also be provided by several short pieces which are placed in the space 74 in a certain division. The shape of the rod or the like is preferably chosen so as to substantially prevent the movement of the tubular elements, at least the movement which separates them from each other. With the solution shown in Fig. 7, it is possible to remove, for example, one pipe element from the pipe panel by removing a rod or the like 76 on both sides thereof by means of a suitable tool. This is a very advantageous feature, especially in connection with a circulating bed reactor, whereby possible repair of the furnace superheater by changing the tube can be carried out very simply and quickly.

Figure 1 below shows a circulating bed reactor operating at atmospheric pressure, but the furnace heater according to the invention is also quite advantageous in combustion plants operating at pressures higher than atmospheric pressure, e.g. at a pressure of 2 to 50 bar.

Although several different embodiments have been illustrated in the accompanying figures, it is to be understood that all variations which are obvious to those skilled in the art will fall within the scope of the appended claims.

Claims (15)

Furnace superheater (24), in which a plurality of adjacent tube elements (36, 362, 366) are mechanically fastened to each other from their opposite surfaces, characterized in that the tube elements (36, 362, 366) are substantially rectangular in cross-section, - adjacent tube elements a groove (72, 368) or the like is provided on the mounting surface (382) and a protrusion (76, 370) or the like on the second mounting surface (380) and that - the tubular elements connected to each other form a substantially planar surface (374, 376). 2. An embodiment according to claim 1, which comprises a number of elements (36, 362, 366) in the form of means and means (72, 368) or means (76, 370) or means, according to which you know väsentligen likadana. 20 Furnace superheater according to Claim 1, characterized in that the tubular elements (36, 362, 366) are connected to one another by means of a groove (72, 368) or the like with substantially similar cross-sectional profiles and a projection (76, 370) or the like. 20 3. A method according to the preceding claims, comprising the elements of a genomic channel, a channel-shaped channel (372), which comprises a tubular material (378), which comprises a portion of the invention, headings 25 parä väsentligen parallella, Plana ytor (374, 476) samt av tvä mot dessa parallella Plana ytor väsentligen vinkelräta fästande ytor (380, 382), pä vilka fästande ytor bildats ett spär eller motsvarande och / eller en utlöpare eller mots är väsentligen likadana. Furnace superheater according to claim 1, characterized in that the tubular element comprises a flow path-forming, preferably circular channel (372) delimited by the tubular material (378) so that the outer surface of the tubular element is spaced from two substantially parallel planar surfaces (374). , 376) and two mounting surfaces (380, 382) substantially perpendicular to these parallel planar surfaces, on the mounting surfaces of which a groove or the like having a substantially similar cross-sectional profile and / or a projection or the like is formed. ♦ • t 4. An embodiment according to any one of claims 2 or 3, further comprising elements (382) for the purpose (368) of the application and 35 and more (380) of the application (370) of the application. 16 101323 Furnace superheater according to Claim 2 or 3, characterized in that a groove (368) or the like is arranged on one fastening surface (382) of the tubular element and a fixed projection (370) or the like on the other (380). 12 101323 5. An embodiment according to any one of claims 2 or 3, comprising a number of elements (368) or a cross-section and a cross-section (370) or a cross-section with a parallel pattern of a parallelogram, a trapezoid, a circle av dessa. Furnace superheater according to claim 2 or 3, characterized in that the groove (368) or the like of the tubular element and the projection (370) or the like are shaped in a substantially parallelepiped, trapezoidal, circular, semicircular, triangular or combination thereof. 6. An embodiment according to claim 2 or 3, which comprises a number of elements (72, 368) or a socket account for the purpose of a socket or a socket (76, 370) or socket (76, 370) or socket. Furnace superheater according to Claim 2 or 3, characterized in that the groove (72, 368) or the like of the tubular element has a cross-sectional area greater than or equal to 10 projections (76, 370) or the like. 7. A method according to claim 1, which can be used as soon as possible and with an additional tube element (36) in the form of a panel according to the order of 15 or more in a circulating fluidized bed reactor. Furnace superheater according to Claim 1, characterized in that a substantially planar panel formed of superheater tube elements (36) is arranged at least partially in the furnace (4) of the circulating bed reactor. An embodiment according to claim 1, which comprises a plurality of ligamentous tubular elements (36) on a plurality of alternatives according to the present invention (72), a plurality of ligamentous bridging tubes and utensils (74), respectively. fästs vid varandra genom att i detta utrymme Placera en Stäng (76) eller motsvarande, vars form efterbildar utrymmets form. 25 Furnace superheater according to Claim 1, characterized in that indentations 20 (72) are arranged on opposite fastening sides of adjacent tube elements (36), which elements form a space (74) between the tubes in parallel, the tubes being fastened to one another by a rod substantially mimicking its shape. (76) or equivalent. 9. A reactor with a circulating vessel, preferably a reactor equipped with a reactor chamber (4), in which case an anhydrous chamber (6) is used for the fast material and the feed chamber (8), a vessel for the fast material reactor chamber, the reactor chamber (16) och ängöverhetta-re (24), vilken ängöverhettare (24) har et flertal vid varandra liggande tubelement (36, 362, 366), vilka me isk isk fästs vid varandra medelst sinä fästande ytor, kännetecknad därav, att 35. tubelementen (36, 362, 366) account for the purpose of the right-hand rectifier, 17 101323 - a number of non-subsidiaries (38, 368) or an additional number (72, 368) see (76, 370) or, in the case of Fig. 5, a room with a picture that is soon to be used (374, 476). A circulating bed reactor comprising a reaction chamber (4), * a solids separator (6) connected thereto and a return channel (8) connecting the solids separator to the reaction chamber, evaporator surfaces (16) and a steam superheater (24) fitted with a rotary bed reactor, The plunger (24) has a plurality of adjacent tubular elements (36, 362, 366) which are mechanically fastened to each other from their opposite mounting surfaces, characterized in that - the tubular elements (36, 362, 366) are substantially rectangular in cross-section; a groove (72, 368) or the like is provided on the second mounting surface (382) and a projection (76, 370) or the like on the second mounting surface (380) and that - the tubular elements connected to each other form a substantially planar surface (374, 376). 5 A circulating reactor according to claim 9, which comprises a reactor comprising a series of reactants (36, 362, 366) in the form of alternatives (72, 368) or by means of a solution (76, 37). , lively account you tvärsnittsprofiler är väsentligen likadana. A rotary bed reactor according to claim 9, characterized in that the superheater tube elements (36, 362, 366) of the reactor superheater are connected to each other by a groove (72, 368) 10 or the like with substantially similar cross-sectional profiles and a protrusion (76, 370) or the like. through. A circulating reactor according to claim 9, comprising reacting a tubular element (362, 366) with a genomic channel, a circulating channel (372) having a tubular material (378), said tubing. of the genomic-20 signal channel, bildas av tvä väsentligen parallel-la, Plana ytor (374, 376) samt av tvä mot dessa parallella Plana ytor väsentligen vinkelräta fästande ytor (380, 382), pä vilka fästande ytor bildats ett ) or the total cost of the service (370) or the total cost of 25 years in the event of a significant loss. A circulating bed reactor according to claim 9, characterized in that the reactor superheater tube element (362, 3636) comprises a flow path forming, preferably a circular channel (372) bounded by the tube material so that the outer surface of the tube element is spaced from the flow channel surface by two substantially a parallel planar surface (374, 376) and two mounting surfaces (380, 382) substantially perpendicular to these parallel planar surfaces, the mounting surfaces having a groove (368) or a similar and / or protrusion (370) having substantially similar cross-sectional profiles, or corresponding. 25 11 101323 A circulating reactor according to claim 10 or 11, having a rotating device, comprising a second (382) image and a spout (72) or a spool (30) and a spool (380) and a spool (370) or spur. Rotary bed reactor according to Claim 10 or 11, characterized in that a groove (72) or the like is arranged on one mounting surface (382) of the tubular element and a projection (370) or the like on the other (380). 30 13. A circulating reactor according to claim 10 or 11, comprising a tubular element (72, 35 368) or a crossover and a guide (76, 370) or a crossover according to the invention, in the form of a parallel stream of 18 , cirkel, halvcirkel, Triangel ell en en-bination av dessa. A rotary bed reactor according to claim 10 or 11, characterized in that the groove (72, 368) or the like of the tubular element and the protrusion (76, 370) or the like are shaped substantially parallel to the trapezoid, trapezoid, 35, semicircle, triangle or a combination thereof. 14 101323 14. A circulating reactor according to claim 10 or 11, comprising a tubular element (72, 368) or an alternating means for the first or second stage (76, 370) or alternating. A circulating bed reactor according to claim 10 or 11, characterized in that the groove (72, 368) or the like of the tubular element has a cross-sectional area greater than or equal to the protrusion (76, 370) or the like. 5 Rotary bed reactor according to Claim 9, characterized in that the opposite fastening sides (72) of the adjacent tube elements (36) are provided with indentations which, in parallel, form a space (74) between the tubes, the tubes being fastened to one another (74). a substantially mimicking rod (76) or the like. 15 101323 1. A set of means (24) and a set of flanges and a flute tube element (36, 362, 366) mechanically connected to a key 5 or more than a set of means (36, 362, 366) - if the tubular elements are present (382) anord-nats et spär (72, 368) or within a maximum of 10 (380) or more (76, 370) or more - vid varandra fästa tubelement bildar en huvudsakligen soon yta (374, 376). 15. A circulating reactor according to claim 9, 10 is further adapted to comprise a plurality of ligated tubular elements (36) in a plurality of second-hand tubes (72); tuberna fasts vid varandra genom att i detta utrymme (74) Placera en Stäng (76) 15 eller motsvarande, vars form efterbildar utrymmets form.