MXPA99011297A - Fluidized circulating bed reactor with internal primary particle separator with p - Google Patents

Abstract

The present invention relates to: An improved circulating fluidized bed (CFB) reactor or combustor arrangement having impact type particle separators for separating solid particles from a flue gas stream / solids flowing through an enclosure of CFB reactor, comprising: a reactor enclosure having an outlet opening, a group of at least two rows of graduated impact type particle separators, located upstream of the exit opening with respect to the gas flow of combustion / solids, a second group of at least two rows of graduated impact type particle separators, located in a passageway below the outlet opening, the combustion / solids gas flows through the passageway; floor of the passage to return particles collected from the flow of combustion gas / solids, the floor located below the second of particle separators

Description

CIRCULATING BED REACTOR WITH INTERNAL PRIMARY PARTICLE SEPARATOR WITH FLOOR FIELD OF THE INVENTION The present invention is generally concerned with circulating fluidized bed (CFB) reactors or combustors having impact type particle separators and more particularly with a reactor of circulating fluidized bed (CFB) or combustor that has an improved impact type primary particle separator. Instead of providing cavity or hopper means with discharge orifices below the collector elements that make up the impact-type primary particle separator, a simple floor provides the internal return of all primary collected solids to a lower portion of the reactor or combustor for its subsequent recirculation.

BACKGROUND OF THE INVENTION? - In circulating fluidized bed (CFB) reactors or combustors, solids that react and do not react are entrained within a reactor envelope by a rising gas flow that transports the solids to an outlet that is in an upper portion of the reactor. the reactor envelope. There, solids are commonly collected by a primary impact type particle separator and returned to a lower portion of the reactor envelope either directly or by means of one or more conduits. The primary particle separator type impact at the outlet of the reactor envelope collects 90% to 97% of circulating solids. If required by the process, an additional solids collector may be installed downstream of the primary particle-type particle separator to collect additional solids for eventual return to the reactor enclosure or enclosure. As described in U.S. Patent No. 5,343,830 issued to Alexander et al., The use of impact type particle separators in circulating fluidized bed (CFB) reactors or combustors is well known. To the extent necessary to describe the general operation of the circulating fluidized bed (CFB) reactors and combustors, the reader is referred to U.S. Patent No. 5,343,830 issued to Alexander et al., The text of which is incorporated herein. by reference in its entirety. In one of the first circulating fluidized bed (CFB) designs, an external impact-type primary particle separator having a plurality of shock elements arranged in stepped rows was used in combination with a non-mechanical L-valve and a secondary particle separator. (multiclon). The rows of stepped impact elements discharged all of their collected solids to a storage hopper located below them and these collected solids were returned to the lower portion of the reactor enclosure via the L valve. The subsequent CFB designs employed additional rows of stepped shock elements that were positioned upstream (with respect to a flow direction of the combustion gas and solids through the apparatus) of the shock elements associated with the storage hopper and its valve L. As described in the patent No. 4,992,085 issued to Belin et al., the text of which is hereby incorporated by reference in its entirety, a plurality of such shock elements are used within an upper portion of the reactor enclosure arranged in at least two tiered rows. The shock elements hang and extend vertically across a width of the reactor outlet, the collected solids fall in an unobstructed manner and not channeled under these collection shock elements along a wall of the rear reactor enclosure of circulating fluidized bed (CFB) or combustor. An important element in these collection shock elements "in the furnace" or "U-beams in the furnace" as they are generally referred to, is a baffle plate near a lower end of these shock elements which improves their efficiency of harvest.

As mentioned in the above-mentioned patent 830 of Alexander, circulating fluidized bed (CFB) reactors or combustors are known in which the two or more rows of shock elements located within the furnace or reactor enclosure are followed by a second arrangement of staggered shock elements that further separate the particles from the gas stream and return them via cavity means and particle return means without external and internal recycle conduits. It is evident that a circulating fluidized bed (CFB) reactor or combustor comprising an even simpler construction would be less expensive and would be welcome in the industry.

FIELD OF THE INVENTION The present invention is generally concerned with the field of circulating fluidized bed reactors or co-circulators (CFB) and provides a simpler, lower cost primary particle separator. In particular, instead of providing cavity means or hopper with discharge orifices below the collector elements that compose the primary particle type impact separator, a simple floor provides the internal return of all the primary collected solids to an interior portion of the reactor or combustor for subsequent recirculation. In its simplest form, the present invention comprises two or more rows of staggered impact type particle separators whose lower ends extend to or close to a single, substantially flat floor The floor can be tilted towards the reactor enclosure, towards a downstream direction with respect to a flow of combustion gas / solids through the CFB, in both directions or even horizontally The impact type particle separators operate in a known manner, collecting solids from the combustion gas / solids flowing to Through a passageway or combustion gases that contain the impact type particle separators and lead them to their lower ends, then these collected solids are separated by the gravity of the combustion gas by one of the following modes: If the floor is inclined to some angle with respect to the horizontal in such a way that the floor is inclined towards a CFB reactor enclosure, the separated solid particles will slide along the floor and into the reactor enclosure along a wall of the rear enclosure thereof. If the floor is tilted so that it is tilted downward in a downstream direction relative to a flow of combustion gas / solids through the combustion passage or gases, the separated solid particles will slide down the floor in the direction of the combustion gases / solids flow where they can be collected in a downstream cavity, hopper or separation channel for collection and inevitable return or return to a lower portion of the reactor enclosure. In some cases, the floor may be provided with a spout to facilitate the solid particles slipping into the reactor enclosure and downstream. In any case, the floor inclination angle, a, will generally be selected such that it is equal to or greater than the rest angle aR for such separate solids. However, the concept of the present invention is also applicable even if the floor is horizontal. The separated solids collected by the particle separators will begin to accumulate to a pile on such a horizontal floor until a slope of the pile reaches the angle of repose R for such separate solids, at which point the Bolides will begin to slide through the pile. either towards the reactor enclosure or in the direction of the flow of combustion gas / solids The particles that slide down the floor back to the reactor enclosure are returned directly for subsequent recirculation, while the particles that slide down the floor in the direction of the flow of combustion gas / solids will be collected in a cavity, hopper or separation channel for its collection and eventual return to a lower portion of the reactor enclosure. ~~ - In cases where the collected solid particles flow into the reactor enclosure, flue gas deflectors / solids means can be used to increase the fraction of collected solid particles that slide down the floor and the reactor enclosure along the wall of the back room. In cases where the collected solid particles flow in the flow direction of the combustion gas / solids, baffle means may or may not be used to improve the flow of solid particles separated along the floor to the downstream cavity, hopper or separation channel. The primary floor-type internal impact particle separator according to the present invention can be used with or without the U-beams inside the upstream furnace. Thus, one aspect of the present invention is concerned with a circulating fluidized bed (CFB) reactor arrangement or improved combustor having impact type particle separators for separating solid particles from a flue gas stream / solids flowing through a reactor enclosure of the circulating fluidized bed reactor (CFB) comprising: a reactor enclosure or enclosure having an exit opening; a group of at least two rows of staged impact type particle separators located upstream of the outlet opening with respect to the flow of the flue gas / solids; a second group of at least two rows of staggered impact-type particle separators located downstream of the exit opening and a floor located below the second group of particle separators. Another aspect of the present invention is concerned with a circulating fluidized bed (CFB) reactor arrangement or improved combustor having impact type particle separators for separating solid particles from a flue gas / solids stream flowing through an envelope or circulating fluidized bed reactor (CFB) enclosure comprising: a reactor enclosure or enclosure having an exit opening or orifice; a group of at least two rows of staged impact type particle separators located downstream from the outlet opening with respect to the flue gas / solids flow and a floor located below the group of particle separators. Yet another aspect of the present invention is concerned with an improved CFB reactor or combustor arrangement that has separators of impact type particles to "separate solid particles from a flue gas stream / solids flowing through a reactor enclosure. of the CFB reactor comprising: a reactor enclosure or enclosure having an exit orifice, at least two rows of staggered impact-type particle separators, at least one row located upstream of the exit opening and orifice, and at least one row located downstream of the outlet orifice with respect to the flow of combustion gas / solids and a floor located below at least one row of particle separators located downstream of the outlet orifice. The various characteristics of novelty characterizing the invention are indicated with particularity in the appended claims a and e are part of this description. For a better understanding of the invention, its operating advantages and specific benefits obtained through its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: Figure 1 is a schematic sectional side elevational view of a portion of a circulating fluidized bed reactor or combustor (CFB) according to a first embodiment of the invention; Figure 2 is a schematic sectional plan view of Figure 1 seen in the direction of the arrows 2-2; Figure 3 is a schematic sectional side elevational view of a portion of a CFB reactor or combustor according to a second embodiment of the invention; Figure 4 is a schematic sectional side elevational view of a portion of a CFB reactor or combustor according to a third embodiment of the invention; Figure 5 is a schematic sectional side elevational view of a portion of a circulating fluidized bed (CFB) reactor or combustor according to a fourth embodiment of the invention; Figure 5A is a schematic sectional side elevational view of a portion of a circulating fluidized bed (CFB) reactor or combustor according to a fifth embodiment of the invention; Figure 6 is a side view in schematic sectional side elevation of a first mode of gas / solids baffle means that can be used in the circulating fluidized bed (CFB) reactor or combustor at a lower end of the particle-type separator elements stepped impact; Figure 7 is a schematic sectional plan view of Figure 6 taken in the direction of arrows 7-7, U-beams 140 are omitted for clarity; Fig. 8 is a schematic sectional side view of a second mode of gas / solids baffle means that can be used at a lower end of the staggered impact type particle separator elements and Fig. 9 is a schematic sectional plan view of Figure 8 taken in the direction of arrows 9-9.

DESCRIPTION OF THE PREFERRED MODALITIES As used herein, the term CFB combustor refers to a type of circulating fluidized bed (CFB) reactor in which a combustion process is carried out. While the present invention is concerned in particular with steam boilers or generators employing circulating fluidized bed combustors (CFB) as the means by which heat is produced, it will be understood that the present invention can be easily employed in a class different from circulating fluidized bed reactor (CFB). For example, the invention could be applied in a reactor that is used for different chemical reactions to a combustion process or where a gas / solids mixture of a combustion process that occurs in any part is provided for the reactor for processing or where the reactor only provides an enclosure in which the particles or solids are entrained in a gas that is not necessarily a by-product or secondary product of a combustion process. With reference generally to the drawings, wherein the like reference numbers represent the same elements or functionally similar elements in all the various lists and in Figures 1 and 2 in particular, a circulating fluidized bed (CFB) reactor or combustor is shown. , generally designated 10, which comprises a reactor enclosure 20 having an upper portion 30 an outlet orifice 40 and a convection passage 50. The front part of the CFB reactor enclosure is defined as the left side of Figures 1 and 2; the back consists of the right sides of these figures and the width of the envelope 20 of the circulating fluidized bed reactor (CFB) is perpendicular to the plane of Figure 1. The reactor enclosure 20 is commonly rectangular in cross section and is defined through the walls 100 of the enclosure. The "walls 100 of the enclosure are usually fluid cooled, which commonly consist of of tubes transporting water and / or steam separated from each other by a steel membrane to obtain a shell 20 of the gas-tight reactor. A combustion gas / solids mixture 110 produced by the circulating fluidized bed (CFB) combustion process that occurs in a lower portion of the reactor shell 20 flows upwardly through the upper portion 30 and inevitably outwardly. the outlet orifice 40 and the convection passage 50. As the combustion gas / solids mixture 110 travels along this path, passes through several stages of removal of solid particles and heat as will be described herein, before being passed into the atmosphere. Located in the upper portion 30 of the reactor shell 20, in the direction of the flow of combustion gas / solids 110 and upstream of the outlet orifice 40 is a first group 130 (one or more rows, preferably two rows) of staggered impact type particle separators 140. The particle separators 140 are non-flat; they may be U-shaped, E-shaped, W-shaped or any other shape having a cup or concave surface configuration to the flow of combustion gases / incoming solids 110. As described above, since the first group 130 of impact type particle separators are upstream of the outlet orifice 40, this first group 130 can also be referred to as the U-beams 130 in the furnace. For convenience, reference will be made later to dispersed particle-type separators 140 such as U-beams 140. U-beams 140 are staggered in such a manner that the flow of combustion gas / solids 110 passes through. of them to allow entrained solid particles to collide with them and be collected in their cup or concave portion and cause the collected particles (referred to in general as 150, regardless of which separator elements 140 to collect them), by the first group 130 falling freely internally and directly along the U-beams towards a lower portion of the reactor enclosure 20. The U-beams 140 also extend fully through the exit orifice 40. U-beams are commonly made of stainless steel due to the high temperature environment. Positioned downstream of the outlet orifice 40 is a second group 160 of impact type particle separators or U-beams 140 (also referred to as spacers 160 of primary impact type particles). The U-beams 140 in this second group 160 of at least two rows of impact-type particle separators (preferably 4 beams), located downstream of the outlet orifice 40, also collect particles 150 from the gas flow of combustion / solids 110. However, in contrast to the known arrangements where the lower ends 170 of such U-beams 140 that make up the second group 160 extend into a cavity below them that is temporarily used to collect and return to the solid particles collected back into the reactor enclosure 20, the CFB reactor 10 according to the present invention is provided only with a floor 180 having no openings or holes therein for the particles to fall through. As illustrated in FIG. 3, the interior impact-type primary particle separator 160 with floor according to the present invention can be used without the U-130 beam upstream group in the oven, but it is preferred that it be used to improve the collection efficiency of solid particles 150. Similarly, while at least two rows of graduated impact-type particle separators or U-beams 140 are required, the at least two rows may be located downstream of the opening or orifice outlet stream or at least one spinneret may be located upstream of the outlet orifice 40 and at least one spinneret may be located downstream of the outlet orifice 40. The floor 180 can and is preferably inclined in such a way that the collected solid particles 150 slide along the floor 180 towards the reactor enclosure 20. However, the floor 180 may be substantially horizontal as illustrated in Figure 4 or may be inclined in such a manner that the collected solid particles 150 are slid along the floor 180 in the direction of flow of the combustion gases / solids 110 where they can be collected in a downstream cavity, hopper or channel 190 as illustrated in Figure 5 for collection and unavoidable return to a lower portion of the reactor enclosure or enclosure. If desired, the floor 180 can still be provided with a peak at 182 such that it not only has a first portion 184 inclined such that the collected solid particles 150 are slid along the floor 180 toward the enclosure 20 of the reactor but also a second portion 186 inclined in such a way that the collected solid particles 150 are slid along the floor 180 in the direction of combustion gas / solids flow where they can be collected in the downstream cavity., hopper or channel 190 as illustrated in Figure 5A for collection and unavoidable return to a lower portion of the reactor enclosure. In any case, where the floor 180 is inclined, the angle of inclination a of the floor will be generally selected in such a way that it is greater than or equal to the angle of repose a R for such separate solids. The floor 180 is preferably substantially planar in construction but if it is inclined it can be provided with a series of channels or slits therein along which the collected solid particles 150 can flow or slide. The floor impact type particle separator concept of the present invention is also applicable even if the floor 180 is horizontal or substantially horizontal (Figure 4). The separated solids 150 collected by the second group of particle separators 160 will begin to accumulate to a stack on such horizontal floor 180 until a slope of the stack reaches the angle of repose aR for such separate solids 150, at which point the solids 150 will begin to slide through the stack, either the reactor enclosure 20 or in the flow direction of the combustion gas / solids 110. The particles 150 that slide 180 through the floor 180 toward the reactor enclosure 20 are returned directly for their subsequent recirculation, while the particles 150 that slide down the floor 180 in the direction of the flow of combustion gas / solids 180 will be collected in the downstream cavity, hopper or removal channel 190 for collection and unavoidable to a lower portion of the reactor enclosure 20. In cases where harvested solid particles 150 flow through the floor 180 into the reactor enclosure 20, flue gas baffle / solids means can be used to increase the fraction of collected solid particles that slide on the floor 180 and the 20 of the reactor along the wall 200 of the rear enclosure. In cases where the collected solid particles 150 flow in the direction of combustion gas flow / solids 110, baffle means may or may not be used to improve the flow of the solid particles 180 separated along the floor 180 to the cavity downstream, chute or "removal" channel 190. With reference to Figures 6 and 7, one embodiment of the combustion gas / solids baffle means referred to generally as 250, comprises a plate 260 having a flange 270 at an upper portion thereof, a substantially horizontal baffle 280 extending from the plate 260- and support means 290 for securing the plate 260 to the rear wall 200 of the reactor enclosure 20. Preferably, the means of flue gas deflector / solids are positioned at a site near an intersection of floor 180 and wall 200 of the rear enclosure.

With reference to Figures 8 and 9, another embodiment of the combustion gas / solid baffle means employs only a plate arrangement 300, 310 secured such as by welding to the lower ends of the U-beams 140 in the furnace and the U-beams 140 comprising the second group of particle separators 160. As illustrated, a continuous plate 300 could be placed on the front of the first U-beams 140 in the furnace, while separate plates 310 could be employed on the back of the successive U-beams 140. The U-beams 140 that make up the second group 160 are preferably of the same design as those comprising the first group 130 and preferably extending to the floor 180, but should be give consideration to the fact that U-beams 140 could expand "grow" downwards as the operating temperature in the CFB reactor increases. The provision of spacing between the lower ends 170 of the U-beams 140 comprising the second group 160 and the floor 180 is a way to prevent contact during operation. However, if such a procedure is desirable or acceptable, a balance must be struck between the provision of proper separation and too much separation because the harvested solid particles 150 could deviate from the lower ends 170 of the beams at ü 140, the which results in not being returned to the reactor enclosure 20 for subsequent recirculation. Alternatively, cooling of such U-beams 140 could be provided to minimize or control such thermal expansion during operation, such as but not limited to the use of indirect cooling as described in U.S. Patent No. 5,809,940 issued to James et al., or by the provision of cooled U-beam structures 140 such as but not limited to those described in U.S. Patent Nos. 5,378,253 and 5,435,820 issued to Daum et al. Still further, a floor 180 or roof structure 210 that is fixed to one end of the U-beam 140 and allows a "sliding fit" in the other or allowing movement at both ends or if it is determined that the contact is relatively non-objectionable, one could employ a floor structure 180 where the U-beams 140 are touching and / or are actually recessed or embedded in the floor 180. Some of the tubes 100 of the reactor shell that form a rear wall 200 of the reactor shell 20 extends upward towards a ceiling 210 of the convection passage 50 to form what is referred to in the art as a "screen" in the outlet orifice 40. The fluid-cooled tubes forming this mesh are generally laterally separated from each other, forming gas conduits (ho shown) through which the combustion gas / solids 110 flows. The floor 180 is commonly cooled and can be formed by some of the tubes 100 of the fluid-cooled envelope or by other fluid-cooled tubes. Referring again to FIGS. 1 and 2 and proceeding through the convection passage 50 in the direction of the flow of combustion gas / solids 110, tube banks can be provided comprising heating surfaces such as superheater, reheater, kettle (water / steam) or even economizer surface, shown schematically in Figures 1 and 2 as 220 and 230 .. The combustion gas / solids 110 that pass through these banks of tubes 220, 230 yields a portion of the contained heat therein to the working fluid within the tubes comprising these tube banks 220, 230 to obtain the thermodynamic work required by any steam turbine or other process- (not shown) associated with the CFB 10 reactor or combustor. to pass through these tube banks 220, 230, the flow of combustion gas / solids 110 can be provided to additional downstream heating surfaces (not shown) and to devices collection of additional particles (not shown).

The present invention minimizes or eliminates the inefficiencies caused by the re-entrainment induced by the deviation of the solids gas through a discharge hopper or cavity located below the separators 160 of primary impact type particles. This means that additional rows of U-140 beams can be added in this group 160, beyond the 4 or 5 rows commonly used to increase the efficiency of particle collection. In addition, the configurations of Figures 4, 5 and 5A can be used where it is desirable to separate the collected solids 150 from the process or to funnel the collected solids back into the reactor enclosure 20 via an external conduit (not shown) or possibly to external devices such as a fluidized bed heat exchanger external (also not shown). While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention can be implemented in another manner without deviating from such principles. present invention can be applied to a new construction involving CFB reactors or combustors or to the repair, replacement or modification of existing CFB reactors or combustors In some embodiments of the invention, certain features or aspects of the invention can be used to Thus, "all of such modalities of changes that fall appropriately into the scope and equivalents of the following claims.

Claims (20)

1. Claims 1. An improved circulating fluid bed (CFB) reactor or combustor arrangement having impact type particle separators for separating solid particles from a flow of combustion gas / solids flowing through a reactor reactor enclosure of circulating fluidized bed (CFB), characterized in that it comprises: an enclosure or envelope of the reactor having an exit opening; a group of at least two rows of staged impact-type particle separators located upstream of the outlet orifice with respect to the flow of combustion gas / solids; a second group of at least two rows of staggered impact-type particle separators located downstream of the outlet orifice and a floor located under the second group of particle separators.
2. 2. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the floor is inclined at an angle with respect to the horizontal in such a manner that the floor is inclined towards the reactor enclosure to cause that the solid particles collected by the second group of particle separators slide down the floor into the reactor enclosure.
3. 3. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the floor is inclined at an angle with respect to the horizontal such that the floor is inclined toward a downstream direction with respect to to the flow of combustion gas / solids through the reactor enclosure to cause the solid particles collected by the second group of particle separators to slide down the floor in the downstream direction.
4. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 3, characterized in that it further comprises means for receiving the collected solid particles that slide down the floor in the downstream direction.
5. 5. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the means for receiving the collected solid particles comprises one of: a cavity, hopper and separation channel.
6. 6. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the floor is substantially horizontal.
7. 7. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the floor is substantially flat.
8. 8. The improved circulating fluidized bed (CFB) reactor or combustor of claim 1, characterized in that the floor is inclined at an angle a with respect to the horizontal.
9. The improved circulating fluidized bed (CFB) reactor or combustor of claim 8, characterized in that the angle of inclination of the floor is greater than or equal to the angle of repose aR of the solid particles collected.
10. 10. The improved circulating fluidized bed (CFB) reactor or combustor of claim 7, characterized in that the floor is provided with one of a series of channels and slits along which the collected solid particles can flow or slide.
11. 11. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that it further comprises a convection passage and heat transfer surface located therein.
12. 12. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 11, characterized in that the heat transfer surface comprises at least one superheater surface, reheater surfaces, boiler surface and economizer surface.
13. 13. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the impact-type particle separators comprise U-beams.
14. 14. The improved circulating fluidized-bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the impact-type particle separators comprise non-planar elements that are U-shaped, E-shaped, shaped or any other shape having a cup or concave surface configuration to the gas / solid stream of combustion.
15. 15. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 8, characterized in that it further comprises gas / solids baffle means associated with the particle separators to reduce the rearrangement of collected solid particles.
16. 16. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 15, characterized in that the combustion gas deflector / solids means comprises a plate having a flange at an upper portion thereof, a baffle substantially horizontal extending from the plate and separation means to secure the plate to a rear wall of the reactor shell at a site near an intersection of the floor and the wall of the back shell.
17. 17. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 15, characterized in that the combustion gas deflector / solids means comprises a plate arrangement secured to the lower ends of the impact type particle separators. .
18. 18. The improved circulating fluidized bed (CFB) reactor or combustor arrangement of claim 1, characterized in that the floor is provided with a peak such that it is provided with a first portion inclined at an angle with respect to the horizontal Such a way that the floor is inclined towards the reactor shell to cause the solid particles to be collected by the second group of particle separators to slide down the first floor portion towards the reactor shell and a second portion inclined at an angle to the reactor shell. with respect to the horizontal in such a manner that the floor is tilted downstream with respect to the flow of combustion gas / solids through the reactor shell to cause the solid particles collected by the second group of particle separators to be slide down the second portion of the floor in the downstream direction.
19. 19. An improved circulating fluid bed (CFB) reactor or combustor arrangement having impact type particle separators for separating solid particles from a combustion gas / solids stream flowing through an enclosure or reactor shell of the fluidized bed reactor circulating (CFB), characterized in that it comprises: a reactor enclosure or enclosure having an exit opening or orifice; a group of at least two rows of staged impact-type particle separators located downstream of the outlet orifice with respect to the flow of combustion gas / solids; a floor located below the group of particle separators. _
20. 20. An improved circulating fluidized bed (CFB) reactor or combustor arrangement having impact type particle separators for separating solid particles from a flue gas stream / solids flowing through an enclosure or shell of the bed reactor fluidized fluid (CFB), characterized in that it comprises: a reactor enclosure or having an opening or exit orifice; at least two rows of staggered impact-type particle separators, at least one row located upstream of the exit orifice and at least one row located downstream of the outlet orifice with respect to the gas flow of combustion / solids; and a floor located below at least one row of particle separators located downstream of the exit orifice.