JPH05237418A - Water-cooled cyclone separator - Google Patents

Abstract

PURPOSE: To attempt the extension of heat transfer tubes, disuse of an intermediate ring header and an increase in heat recovery by providing a cylindrical section, a roof section and a hopper section and forming these sections with a plurality of parallel extended water cooled heat transfer tubes. CONSTITUTION: A cyclone separator 2 has a roof section 4 connected to an inner cylinder (inner cylinder) 13, a cylinder section (outer cylinder) 6 provided with an inlet 6a and a conically shaped hopper section 8. A lower part ring header 10 and an upper part ring header 12 are arranged at a lower end of the hopper section 8 and at an upper end of the roof section 4 respectively. The cylinder section 6 and the hopper section 8 are formed by a plurality of parallel water cooling tubes 14 and each tube 14 is separated from each other by a plurality of fins 16. A circulating apparatus has a steam drum 22 of natural circulation which is connected to an upper part ring header 12 through a piping 24 and each branched piping 26 and 28. A pump 36 circulates liquid through each pipe 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cyclone separator, and more particularly to a cyclone separator having an extended heat exchange portion in its hopper area.

[0002]

Fluidized bed reactors, combustors, or gas systems have been known for some time. In these devices, air is directed through a bed of particulate material containing fossil fuels such as coal and a sorbent for sulfur generated by the combustion of coal, and fluidizes the bed, while at a relatively low temperature. Promote the combustion of fuel in. When converting the water to steam using the heat generated by the fluidized bed, as in the case of a steam generator, the fluidized bed apparatus releases high heat, high sorption of sulfur,
It provides a preferred combination of low emissions of nitrogen oxides and fuel variability.

The most typical fluidized bed combustors are commonly referred to as bubbling fluidized beds. In this fluidized bed, a bed of particulate material is supported by an air distribution plate into which combustion support air is introduced through its plurality of perforations to expand the particulate material and cause it to expand into a suspended or fluidized state. State. When the reactor is in the form of a steam generator, the walls of the reactor are formed by a plurality of water cooled heat transfer tubes. The heat generated by the combustion in the fluidized bed is transferred to a heat exchange medium such as water, steam or a combination that is circulated through the tubes. These pipes are usually connected to a natural water circulation circuit, including a steam drum, to separate the water from the steam produced, which steam is supplied to a turbine for power generation or a user of the steam. The tubes eliminate the need for expensive duct systems and expansion joints with high temperature resistant linings.

This type of fluidized bed combustor includes a cyclone separator normally positioned to receive the gaseous effluent from the bubbling fluidized bed. The particulate material introduced into the separator contains gas accompanied by solid fuel particles. The separator utilizes centrifugal force to separate the solid particles from the gas.

A cyclone separator for separating solid fuel particles discharged from a combustion device or the like and a gas is usually provided with a hopper section at a lower portion thereof for collecting the solid fuel particles. U.S. Pat. No. 4,994,250 discloses an improved cyclone separator with walls made of water cooled heat transfer tubes. The addition of tubing minimizes the need for expensive duct systems and expansion joints with high thermal refractory linings between the reactor and the cyclone separator and between the cyclone separator and the heat recovery section. The walls of the separator are formed by tubes of constant diameter connected together by fins. Each fin extends from one tube and is welded to an adjacent tube to form an airtight wall. According to this configuration, the hopper area of the separator is conical and the circumference and diameter of the hopper area are
It decreases from the top to the bottom. Therefore, the circumference of the hopper area is reduced, but the diameter of the tube in the wall is constant. The size of the fins that connect the wall tubes is
Gradually decrease from top to bottom to counteract the decrease in circumference. A problem arises when the size of the fins connecting the tubes can no longer be reduced because the tubes are in contact with each other and there is no space for the fins. This problem occurs somewhere above the bottom of the hopper area, so the tube cannot extend the full length of the hopper area.

One solution to this problem is to provide an intermediate ring header, thereby reducing the number of tubes extending between this intermediate ring header and the lower ring header, thereby reducing the number of tubes in the hopper area. To allow the tube to extend over its entire length. However, the addition of the intermediate ring header increases the fluidized bed combustor cost.

[0007]

SUMMARY OF THE INVENTION Accordingly, one object of the present invention is to provide a cyclone separator of the above type in which a water cooled heat transfer tube extends over the entire length of the hopper section. Especially.

Another object of the invention is to provide a cyclone separator of the type mentioned at the outset in which the need for an intermediate ring header is eliminated.

A further object of the invention is to provide a cyclone separator of the type mentioned at the outset, which has an increased heat recovery.

[0010]

In order to achieve these objects, a separator according to the present invention comprises a cylindrical portion, a roof portion, and
A hopper section, each of which is formed by a plurality of water cooled heat transfer tubes extending in parallel relationship. One ring header is provided at the top and one at the bottom of the separator to allow cooling water, steam, or a mixture thereof to pass through the tubes. An inner cylinder is provided in combination with the cylindrical portion of the separator to define an annular chamber for separating the mixture of gas and solid particles from the gas by centrifugal force. Accept to. With this separation, the solid particles fall into the hopper area of the separator for disposal or recycling, and the gas passes upward through the inner tube of the separator towards the external heat recovery device. Flowing. According to a main feature of the invention, extending the wall of the water cooled tube over the entire length of the hopper section is
Achieved by reducing the size of the tubes or by reducing the number of tubes, in neither case the need for intermediate ring headers. Therefore, either embodiment can be incorporated into a natural circulation system or a pump system.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, reference numeral 2 generally designates a cyclone separator according to the invention which comprises a roof part 4, a cylindrical part 6 with an inlet 6a and a conical hopper section 8. Shows. The lower ring header 10 is located in the hopper area 8
And the upper ring header 12 is disposed on the upper end of the roof portion 4, respectively. The roof portion 4 is connected to the inner cylinder 13 by a known means such as welding. The connection between the inner cylinder 13 and the roof portion 4 is airtight. The inner cylinder 13 is aligned with the cylindrical portion 6 in a concentric relationship. The lower part of the inner cylinder 13 extends into the cylindrical portion 6. The upper portion of the inner cylinder 13 extends above the cyclone separator 2.

As better shown in FIG. 2, the cylindrical portion 6 and the hopper section 8 are formed by a series of parallel spaced apart tubes 14 of the same diameter. The tube 14 is connected at the lower end to the lower ring header 10 and runs the length of the separator. Although the upper portion of the cylindrical portion 6 is not shown in FIG. 2, the remaining portion of the cylindrical portion 6 and the roof portion 4 are also formed by the same group of pipes 14. A portion of the tube 14 is bent away from the plane of the cylinder 6 to form the inlet 6a (Fig. 1). This inlet allows the gas containing the solid particles to be introduced tangentially into the annular chamber.

The tubes 14 are separated from each other by a plurality of fins 16, which extend from the diametrically opposed portions of each tube over the entire length of the tube and are known in the art. The separator 2 is made airtight by being connected to the tube in a manner such as by welding. The width of each fin 16 is constant in the cylindrical portion 6 except for the inlet 6a, and as will be described later, the roof portion 4 and the hopper area 8 are provided.
However, it is fluctuating.

As shown in FIG. 1, the tube 14 extends generally horizontally inwardly from the upper ring header 12 and then
Bent vertically downward. The pipe 14 is then bent outwards in a substantially horizontal direction, completing the roof part 4 and then bent vertically downwards to form the cylindrical part 6. The tube 14 is bent inwardly at a slight angle at the lower end of the cylindrical part 6 to form a conical hopper section 8.

The inlet 6a, the roof 4 and the cylinder 6 are all described in the Applicant's US Pat. No. 4,746,337, which is hereby incorporated by reference.

As shown in FIG. 2, the width of the fins 16 inevitably decreases from the top to the bottom of the conical hopper portion 8 and eventually the tubes 14 contact each other, negating the need for fins. .. The tube 14 is divided into two sets 14a, 14b to compensate for the reduction in circumference and diameter of the hopper section 8. After extending the length of the hopper section 8, the tubes forming the set 14a are bent radially outward and then downwardly into the lower ring header 10. The tubes forming the set 14b extend a downward distance along the hopper section 8 before being ejected or bent radially outward and then bent downward toward the lower ring header 10. ing. The lengths of the sets 14a and 14b are substantially equal from the upper ring header 12 to the lower ring header 10.

As shown in FIG. 3, the lower portion of the hopper section 8 is formed solely by the tubes of set 14a in combination with the fins 16. The tubes of set 14a are bent radially outward at the bottom of hopper section 8 and extend downward into lower ring header 10. The tubes 14 of the set 14b drawn to the top of this figure extend vertically into the lower ring header 10.

FIG. 1 illustrates a circulation system utilized with the separator 2 of the present invention. The circulation device includes a natural circulation steam drum 22, which is connected to the upper ring header 12 via a pipe 24 and branch pipes 26 and 28. The downcomer pipe 30 and the branch pipe 32 connect the steam drum 22 to the lower ring header 10. The steam circulates with water from the steam drum 22 and is selected by gravity in the lower ring header 10 by the downcomer 30 and moves upward from the lower ring header 10 through the pipe 14 by natural convection as described below. To do.

The separator 2 of the present invention is a part of a boiler apparatus including a fluidized bed reactor and the like (not shown) arranged in the vicinity thereof.

In operation, the inlet 6a receives from the reactor a hot gaseous mixture containing gas from the fluidized bed and associated fine solid fuel particles. The inlet 6a is arranged to introduce the hot gaseous mixture tangentially into the cylindrical part 6. Therefore, the entrained solid particles collide with the inner wall of the cylindrical portion 6 due to the centrifugal force, and the solid particles are collected there and fall downward into the hopper zone 8 by the action of gravity. The solid particles collected at the bottom of the hopper area can be reused by external means (not shown) by means known in the art.
Be led to. The relatively clean gas remaining in the chamber cannot flow upward due to the roof 4 and the inner cylinder 13 connected thereto, so that this gas is forced into the inner cylinder 13 via its lower end. Inflow. Before being discharged from the upper end of the inner cylinder 13, the gas migrates along the length of the inner cylinder 13 and is directed to an external device (not shown) for reuse. Water, steam or a mixture thereof moves from the steam drum 22 to the lower ring header 10 via the pipes 30 and 32,
Natural convection causes upward flow through the tube 14 of the hopper section 8, the cylindrical section 6, the inlet 6a and the roof section 4. The heated water, steam or mixture thereof is then transferred from the roof 4 to the upper ring header 12 and to the pipes 24, 26, 28.
And then flow into the steam drum 22. Therefore, the separator 2 is kept at a relatively low temperature by the circulating fluid.

The device of the present invention offers several advantages. For example, heat loss is reduced, the heat recovery area of the hopper area is increased, and the need for internal refractory materials is minimized.

Various modifications may be made within the scope of the invention. As an example, the inner cylinder 13 is, like the separator 2,
It may be formed by a water-cooled pipe, or the inner cylinder 13 may be connected to a fluid circuit including the steam drum 22. A forced circulation device may be used instead of the natural circulation system described above. In this case, a pump 36 for receiving the fluid from the steam drum 22 and pumping the fluid through the branch pipe 32 and the pipe 14 is arranged in the downcomer pipe 30.

A variation of the separator of the present invention is indicated generally by the numeral 40 in FIG. Separator 40
Comprises a cylindrical portion 42 and a conical lower hopper section 44. The entire separator 40, including the hopper section 44,
It is formed by a series of spaced parallel tubes 46 of constant diameter. The tube 46 is separated by a plurality of fins 48, which fins
It extends from the diametrically opposite part of each tube over the entire length of the tube and is connected to the tube by any known method, for example welding. The width of the fins 48 is necessarily reduced from the top to the bottom in the conical hopper section 44 until the adjacent tubes directly contact each other, negating the need for fins. Each tube accommodates a reduction in the circumference and diameter of the hopper section 44 and extends to or above the area designated by 50 to extend the hopper section 44 below the area where the adjacent tubes first contact. Is being swaged in. The small diameter portion of the tube 46 extends over the remaining length of the hopper section 44 and is bent radially outward at the bottom of the hopper section and then bent downwardly into the lower ring header 52. There is.

The modified embodiment shown in FIG. 4 has all the devices and functions of the first embodiment of the invention shown in FIG. 1 and includes all modifications.

The swaging feature of this embodiment provides several advantages. As an example, heat loss is reduced, the heat recovery area of the hopper area is increased, and the need for internal refractory materials is minimized. These advantages are reached without the extra cost of the intermediate ring header.

The above-described embodiments can be modified in many ways, including withdrawing or swaging the tube at many points to increase the flexibility of the design parameters.

Although the present invention has been described above with respect to specific embodiments thereof, the specific configurations described above are merely illustrative and are not intended to limit the invention.

[Brief description of drawings]

FIG. 1 is a schematic side view of a cyclone separator according to the present invention including a water circulation system.

FIG. 2 is an enlarged perspective view of a part of the cyclone separator of the present invention.

3 is a cross-sectional view taken along line 3-3 of FIG.

FIG. 4 is an enlarged perspective view similar to FIG. 2, showing a modified example of the cyclone separator of the present invention.

[Explanation of Codes] 2 Cyclone Separator 6 Cylindrical Part (External Cylinder) 8 Hopper Area 13 Inner Cylinder (Internal Cylinder) 14 Tube 36 Pump (Circulating Means)

Claims (3)

[Claims] 1. An inner cylinder and an outer cylinder extending concentrically around the inner cylinder to extend vertically in a parallel relationship to form an annular chamber between the inner cylinder and the outer cylinder. A plurality of tubes including compartments, the other compartments of these tubes being bent inwardly to form a conical hopper section extending downwardly of the outer cylinder and at least a portion of said tubes. The morphology is designed to allow the diameter of the hopper zone at the lower end of the tubes to be reduced as compared to the diameters of these tubes in other configurations, and further to allow fluid flow through the tubes. And a circulating means for circulating and a means for guiding a gas containing solid particles through the annular chamber in order to separate the solid particles from the gas by centrifugal force, and the separated gas is discharged from the inner cylinder. And the separated solids are A cyclone separator characterized by being dropped onto the bottom of the hopper area for disposal or recycling. 2. An inner cylinder and an outer cylinder extending concentrically around the inner cylinder to extend vertically in a parallel relationship to form an annular chamber between the inner cylinder and the outer cylinder. A plurality of tubes including compartments, the other compartments of these tubes being bent inwardly to form a conical hopper section extending downwardly of the outer cylinder, a portion of the tubes being , In at least one position, withdrawing from the wall of the hopper section so that the rest of the tubes can extend the hopper area beyond that position, each position of the tubes being in the absence of withdrawal. At a position where it should have been in contact with an adjacent tube, a means for circulating a fluid through the tube, and a gas containing solid particles for separating the solid particles from the gas by centrifugal force are passed through the annular chamber. And means for guiding, The cyclone separator characterized in that the separated gas is discharged from the inner cylinder, and the separated solid matter is dropped on the bottom of the hopper section for disposal or recycling. 3. An inner cylinder and an outer cylinder extending concentrically around the inner cylinder to extend vertically in a parallel relationship to form an annular chamber between the inner cylinder and the outer cylinder. A plurality of tubes including compartments, the other compartments of these tubes being bent inwardly to form a conical hopper section extending downwardly of the outer cylinder to form the hopper section. At least a portion of the tube is swaged at at least one location to reduce the diameter of the tube and extend the length of the hopper section forward from the position, the position of the tube A location where it should come into contact with an adjacent tube when not swaged, and further includes means for circulating a fluid through the tube and solid particles for separating the solid particles from the gas by centrifugal force. Gas through the annular chamber A cyclone, characterized in that the separated gas is discharged from the inner cylinder and the separated solids are dropped onto the bottom of the hopper zone for disposal or recycling. Separator.