CN220186800U

CN220186800U - Vortex built-in separator for circulating fluidized bed boiler

Info

Publication number: CN220186800U
Application number: CN202321025253.5U
Authority: CN
Inventors: 方向勇; 晏平; 蒲小刚; 史效武; 孙青兰; 黄彩云
Original assignee: Turpan Kaineng Environmental Protection Energy Co ltd; Yangjiang Kaineng Environmental Protection Energy Co ltd; Guangdong Dongshi Kaineng Energy Co ltd
Current assignee: Turpan Kaineng Environmental Protection Energy Co ltd; Yangjiang Kaineng Environmental Protection Energy Co ltd; Guangdong Dongshi Kaineng Energy Co ltd
Priority date: 2023-04-28
Filing date: 2023-04-28
Publication date: 2023-12-15
Anticipated expiration: 2033-04-28

Abstract

The utility model relates to the technical field of boilers, and particularly discloses a vortex built-in separator for a circulating fluidized bed boiler. It comprises the following steps: the device comprises a left membrane type water wall, a right membrane type water wall and a lower membrane type water wall which form a separation chamber for air flow vortex movement, wherein a gap is reserved between the upper end of the left membrane type water wall and the right membrane type water wall to form an air flow inlet, a gap is reserved between the lower end of the right membrane type water wall and the upper end of the lower membrane type water wall to form an air flow outlet, a return channel communicated with the separation chamber is formed between the lower part of the left membrane type water wall and the lower part of the lower membrane type water wall, an inlet of the return channel is positioned at the downwind position of the air flow outlet and below the tangential direction of the separation chamber, and the bottom of the return channel is communicated with a boiler hearth. According to the scheme, the inertia force of the movement of the particulate matters along the inner wall of the separation chamber is effectively increased, so that the separation efficiency of materials is greatly improved, the circulation rate of the materials is increased, the combustion of the boiler is improved, and the efficiency of the boiler is improved.

Description

Vortex built-in separator for circulating fluidized bed boiler

Technical Field

The utility model relates to the technical field of boilers, and particularly discloses a vortex built-in separator for a circulating fluidized bed boiler.

Background

The separator is one of main matching equipment of the circulating fluidized bed boiler, and can be divided into a cyclone separator, an inertial separator, a combined separator and the like according to the structural form of the separator.

The vortex separator of the circulating fluidized bed boiler utilizes the rotational motion of gas-solid two-phase fluid to separate solid particles from air flow under the action of inertia force. When dust-containing air flow enters the separator from the outlet of the hearth, the air flow is changed from linear operation to vortex motion due to the constraint of the separator, the rotating air flow moves in a vortex shape along the inner wall of the separator, the dust-containing air generates inertial force in the rotating process, unburnt particles with the gravity larger than that of the air are thrown to the tangential position of the inner wall of the separator, move downwards along the membrane wall of the separator arranged at the lower part of the outlet of the separator, and finally return to the hearth to be burnt again, so that the aim of gas-solid separation is fulfilled.

The existing vortex type separator is generally composed of a left membrane type water-cooled wall, a middle membrane type water-cooled wall and a right membrane type water-cooled wall which are made into special vortex type lines, such as a smoke dust separation guiding device for a circulating fluidized bed boiler disclosed in patent number 201020552106.X, and the smoke dust separation guiding device comprises a smoke dust separator composed of a left membrane type water-cooled wall, a middle membrane type water-cooled wall and a right membrane type water-cooled wall, wherein the joint of the upper end of the middle membrane type water-cooled wall and the left membrane type water-cooled wall and the right membrane type water-cooled wall forms an inlet of the smoke dust separator, a smoke flue is arranged in the middle of a rear wall of the circulating fluidized bed boiler, the smoke flue is used as an outlet of the separator, and smoke gas entering from the separator flows out from the smoke flue after being separated.

Because the airflow inlet of the vortex type separator is positioned at the outer side of the separation chamber, and the airflow outlet is positioned at the middle part of the separation chamber, the vortex flow radius of airflow can be gradually reduced after the airflow enters from the inlet and finally flows out from the outlet at the middle part of the separation chamber, so that most of solids in the flue gas are thrown onto the water-cooled membrane wall in the earlier stage of entering the separator, and smaller particle solids in the flue gas are difficult to contact the water-cooled membrane wall along with the reduction of the vortex flow radius of the flue gas in the later stage, the solid-gas separation effect of the separator is finally poor, and the operation requirement of the circulating fluidized bed boiler is difficult to meet.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provides a vortex built-in separator for a circulating fluidized bed boiler.

The utility model discloses a vortex built-in separator for a circulating fluidized bed boiler, which adopts the following technical scheme:

a vortex built-in separator for a circulating fluidized bed boiler, comprising: the separator is installed in boiler furnace, the separator includes: left diaphragm-type water-cooling wall, right diaphragm-type water-cooling wall and lower diaphragm-type water-cooling wall, left diaphragm-type water-cooling wall, right diaphragm-type water-cooling wall and lower diaphragm-type water-cooling wall are around forming the separation chamber that supplies air current vortex-like motion, leave the clearance and form the air current entry between the upper end of left diaphragm-type water-cooling wall and the right diaphragm-type water-cooling wall, leave the clearance and form the air current export between the lower extreme of right diaphragm-type water-cooling wall and the upper end of lower diaphragm-type water-cooling wall, constitute the returning charge passageway with the separation chamber intercommunication between the lower part of left diaphragm-type water-cooling wall and the lower part of lower diaphragm-type water-cooling wall, the entry of returning charge passageway is located the downwind position of air current export and is in the below of separation chamber tangential direction, the bottom of returning charge passageway with boiler furnace intercommunication.

Preferably, the flue gas speed of the air flow outlet is 15-18 m/s, and the interval between the air flow outlets is 50-80 cm.

Preferably, the separation chamber has an inner wall diameter length from the gas flow outlet of 3: (0.5-0.8), wherein the ratio of the air flow outlet spacing to the air flow inlet spacing is 1:1.

Preferably, the upper end of the left membrane water wall is provided with an inlet header, the lower end of the right membrane water wall is provided with an upper header, the upper end of the lower membrane water wall is provided with a lower header, a gap is reserved between the inlet header and the right membrane water wall, an air flow inlet is formed, a gap is reserved between the upper header and the lower header, an air flow outlet is formed, and the inlet header, the upper header and the lower header are connected through a communicating pipe.

Preferably, a rear wall of the boiler furnace is provided with a rear wall water-cooling membrane wall, the rear wall water-cooling membrane wall and the lower part of the left membrane water-cooling wall form a self-sealing channel, the self-sealing channel is communicated with the lower part of the return channel, and a blanking port is arranged at the bottom of the self-sealing channel and is communicated with the boiler furnace.

Further preferably, the bottom of the self-sealing channel is a porous structure to form a blanking port.

Preferably, the width of the material returning channel gradually increases from top to bottom.

Preferably, the left membrane water wall forming the return channel is 45+/-2 degrees with the vertical direction.

Preferably, the airflow outlet is provided with a slag condensing pipe and a groove-type separator along the flowing direction of the flue gas.

Further preferably, the trough separators are arranged in a vertically spaced apart relationship and in a staggered array.

Compared with the prior art, the utility model at least comprises the following beneficial effects:

according to the scheme, through modifying the structure of the separation chamber, the flue gas entering the separation chamber tangentially can continuously form vortex-like motion along the left membrane type water-cooled wall and the right membrane type water-cooled wall of the separation chamber, so that the inertia force of the movement of particles along the inner wall of the separation chamber is increased, the probability of collision of fuel particles in the separation chamber is effectively increased, and compared with an outlet positioned in the center of the vortex, the circulation rate of materials is greatly increased, so that the solid-gas separation efficiency of the flue gas is improved, the combustion of a boiler is improved, and the efficiency of the boiler is improved.

Drawings

Fig. 1 is a schematic view showing the overall structure of a circulating fluidized bed boiler according to the present embodiment;

fig. 2 is a schematic view showing the structure of a vortex built-in separator for a circulating fluidized bed boiler according to the present embodiment;

FIG. 3 is a cross-sectional view of A-A/B-B of FIG. 1;

FIG. 4 is a cross-sectional view of C-C/D-D of FIG. 1.

Reference numerals illustrate:

1. a boiler furnace; 2. a separation chamber; 3. a left membrane water wall; 31. an inlet header; 4. a right membrane water wall; 41. an upper header; 5. a lower membrane water wall; 51. a lower header; 6. a rear wall water-cooled membrane wall; 7. an air flow inlet; 8. an air flow outlet; 9. a return channel; 10. self-sealing the channel; 11. a blanking port; 12. a slag condensing pipe; 13. a trough separator; 14. a soot blower.

Detailed Description

In order that the above-recited objects, features and advantages of the present utility model will become more readily apparent, a more particular description of the utility model will be rendered by reference to the appended drawings and appended detailed description.

A vortex built-in separator for a circulating fluidized bed boiler, with reference to fig. 1-4, which separator is mounted in a boiler furnace 1, which separator comprises: left membrane water wall 3, right membrane water wall 4, and lower membrane water wall 5, left membrane water wall 3, right membrane water wall 4, and lower membrane water wall 5 surround separation chamber 1 configured for swirling motion of flue gas.

The upper end of the left membrane water wall 3 is provided with an inlet header 31, the lower end of the right membrane water wall 4 is provided with an upper header 41, the upper end of the lower membrane water wall 5 is provided with a lower header 51, and the inlet header 31, the upper header 41 and the lower header 51 are connected through communicating pipes. A gap is reserved between the inlet header 31 and the right membrane water wall 4, and the gap is positioned at the upper part of the separation chamber and is used as an air flow inlet 7 of the separation chamber 1; a gap is left between the upper header 41 and the lower header 51, and is positioned at the lower part of the separation chamber 1 as an air flow outlet 8 of the separation chamber; a return channel 9 communicated with the separation chamber 1 is formed between the lower part of the left membrane water wall 3 and the lower part of the lower membrane water wall 5, the inlet of the return channel 9 is positioned at the downwind position of the airflow outlet 8 and below the tangential direction of the separation chamber 1, and the bottom of the return channel 9 is communicated with the boiler furnace 1. The flue gas enters the separation chamber 1 from the air inlet 7 to perform vortex-like movement, unburned fuel particles are separated out under the action of inertia force at the air outlet 8 and move downwards along a return channel 9 arranged below the air outlet 8, the return channel 8 is communicated with the boiler hearth 1 to continuously burn the fuel particles, and the flue gas after separating the materials overflows from the separator outlet and moves to the back flue.

According to the scheme, the gas outlet 8 of the separation chamber 1 is adjusted, so that the gas inlet 7 and the gas outlet 8 are respectively arranged at the two side edges of the separation chamber 1, and the flue gas entering the separation chamber 1 tangentially can continuously form vortex-like motion along the inner wall of the separation chamber 1, so that the probability of collision of fuel particles in the separation chamber 1 is effectively increased. In addition, the flue gas in the earlier stage of the vortex flow entering the separation chamber 1 can continue the vortex flow due to the fact that the flue gas in the later stage newly enters the separation chamber 1 is crowded, the inertia force of the movement of particles along the inner wall of the separation chamber 1 is increased, smaller fuel particles which are not separated in the initial stage of the vortex flow can continue to run along the water cooling wall of the separation chamber 1, the fuel particles in part of the flue gas can overflow from the air flow outlet 8 until the content of the fuel particles in the flue gas is reduced to a certain value, and therefore the effect of greatly improving the solid-gas separation efficiency is achieved.

Analyzing the reasons of low separation efficiency in the prior art, when the distance between air flow outlets is large, the flow speed of the flue gas is reduced, and the flue gas vortex effect is poor at the moment, so that part of fuel particles are easy to escape along with the flue gas, and the separation efficiency is reduced; when the interval of the airflow outlet is small, the flue gas flow speed is improved, the flue gas vortex effect is obvious at the moment, but the particle rebound is aggravated, the separated fuel particles can be reeled into the cyclone flow by high-speed flue gas to be taken away, the separation efficiency is affected instead, and the flue gas is scoured, so that the abrasion of a heating surface is aggravated, and the boiler efficiency is adversely affected.

The scheme can achieve the effect of reducing the escape of the particulate matters and has good separation efficiency.

On one hand, the interval between the air outlets 8 is set to be 50-80 cm, the flue gas speed of the air outlets 8 is controlled to be 15-18 m/s, the movement momentum of the particles is obtained according to the particle size and specific gravity, the upper and lower heights or intervals of the air outlets 8 are calculated, the vectors of the particles are ensured to be larger than the vectors of the particles escaping from the upper and lower intervals of the outlets, and the successful separation of the particles is ensured, so that the escape phenomenon of the particles from the air outlets 8 is reduced to the greatest extent.

On the other hand, referring specifically to fig. 2, the separation chamber 2 has an inner wall diameter length L1 and a distance L2 from the air flow outlet 8 of 3: (0.5-0.8), the ratio of the space between the air flow outlets 8 and the space between the air flow inlets 7 is 1:1, and by designing the length of the gap between the inlet and the outlet to be smaller than that of the whole separation chamber 1, the flowing smoke formed by the smaller inlet and outlet can have longer relative vortex paths in the separation chamber, so that the special size design of the scheme enhances the vortex effect of the separation chamber 1, compensates the reduction of the vortex effect caused by low speed of the smoke and better reduces the escape condition of particles; meanwhile, the longer relative vortex path can enable particles not to rebound easily under high-speed smoke to be taken away by the smoke, the defect that the speed of the smoke is limited to be improved is overcome, and finally good separation efficiency can be achieved.

Therefore, the special design transformation is carried out on the separation chamber 1, so that the separation chamber is organically combined with the speed control of the flue gas, the difficult problem that fuel particles are easy to escape from the air flow outlet 8 is solved, the problem that the speed of the flue gas affects the separation efficiency is solved, and the efficiency of the boiler is finally improved.

In addition, most of the traditional separators are formed by water wall pipes into multi-gap airflow inlets and outlets, and as the water wall pipes are arranged at the gap type outlets and inlets, after the gas-solid two-phase flow collides with the inlet water wall of the separator, fuel can be adhered to the water wall pipes due to the characteristic influence, and even the problems of blockage of the outlets and inlets of the separator are caused. The inlet header 31, the upper header 41 and the lower header 51 are designed, as shown in fig. 3, so that the air flow inlet 7 and the air flow outlet 8 of the scheme are not blocked by water cooling wall pipes, and therefore, the flue gas is ensured to enter the separation chamber 1 from the air flow inlet 7 at a certain flow rate to perform vortex motion, and the separated air can be discharged from the air flow outlet 8 without obstruction. Therefore, the problem that potential safety hazards are brought to the operation of the boiler due to blockage of the outlet and the inlet in the prior art is solved, the operation safety of the boiler is guaranteed, the operation period of the boiler is prolonged, and the operation period of the boiler is prolonged to at least 90 days from the original operation period of about 30 days.

In order to further improve the returning condition of returning particles and the running stability of the boiler, the width of the returning channel 9 is gradually increased from top to bottom, and the left membrane water wall 3 (namely the lower part of the left membrane water wall 3) forming the returning channel 9 forms 45+/-2 degrees with the vertical direction, so that the fuel particles roll down and accelerate, and the fuel particles quickly return to the bottom of the boiler hearth 1. In addition, the back wall of the boiler furnace 1 is provided with a back wall water-cooling membrane wall 6, the back wall water-cooling membrane wall 6 and the lower part of the left membrane water-cooling wall 3 form a self-sealing channel 10, referring to fig. 4, the self-sealing channel 10 is communicated with the lower part of a return channel 9 through a transverse interval opening, the bottom of the self-sealing channel 10 is provided with a blanking opening 11 to be communicated with the boiler furnace 1, and return particles fall into the self-sealing channel 10 from the return channel 9 through the transverse interval opening and are discharged from the blanking opening 11 of the self-sealing channel 10 successively. By arranging the self-sealing channel 10, the accumulation of the return materials at the bottom of the channel and the pressure of the hearth form self-sealing and self-balancing operation, thereby preventing the short circuit of smoke and realizing the safe operation of the boiler. Specifically, the bottom of the self-sealing channel 10 is a porous structure to form the blanking port 11, which is helpful for the channel to form a self-sealing effect, and the fuel particles can flow smoothly.

As a preferred scheme, referring to fig. 1, the airflow outlet 8 is provided with a slag condensing pipe 12 and a trough type separator 13 along the flow direction of the flue gas, and ash particles in the flue gas are solidified by utilizing the part of the rear wall water-cooled membrane wall 6 pipe arranged in the flue; meanwhile, the heat-conducting material is also used as a part of a radiation heating surface to generate partial steam; in addition, the flow equalization is carried out on the flue gas, and the residual rotational kinetic energy of the flue gas is reduced. The groove-shaped separators 13 are vertically arranged at intervals and are arranged in a plurality of rows in staggered mode, and the groove-shaped separators 13 of the embodiment are vertically arranged in three rows in staggered mode and are used for further separating particles in the flue gas, and the separated particles slide into the return channel 9 along the flue with a certain inclination. The soot blower 14 is also arranged at the position of the groove-shaped separator 13, and the soot blower 14 is a steam soot blower, so that the accumulated particulate matters at the bottom of the flue can be periodically purged to reduce the accumulation at the position.

The foregoing has outlined rather broadly the more detailed description of the utility model in order that the detailed description of the utility model that follows may be better understood, and in order that the present principles and embodiments may be better understood; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present utility model, the present description should not be construed as limiting the present utility model in view of the above.

Claims

1. A vortex built-in separator for a circulating fluidized bed boiler, wherein the separator is mounted in a boiler furnace, the separator comprising: left diaphragm-type water-cooling wall, right diaphragm-type water-cooling wall and lower diaphragm-type water-cooling wall, left diaphragm-type water-cooling wall, right diaphragm-type water-cooling wall and lower diaphragm-type water-cooling wall are around forming the separation chamber that supplies air current vortex-like motion, leave the clearance and form the air current entry between the upper end of left diaphragm-type water-cooling wall and the right diaphragm-type water-cooling wall, leave the clearance and form the air current export between the lower extreme of right diaphragm-type water-cooling wall and the upper end of lower diaphragm-type water-cooling wall, constitute the returning charge passageway with the separation chamber intercommunication between the lower part of left diaphragm-type water-cooling wall and the lower part of lower diaphragm-type water-cooling wall, the entry of returning charge passageway is located the downwind position of air current export and is in the below of separation chamber tangential direction, the bottom of returning charge passageway with boiler furnace intercommunication.

2. A cyclone built-in separator for a circulating fluidized bed boiler according to claim 1, wherein the flue gas velocity of the gas flow outlet is 15-18 m/s, and the interval of the gas flow outlet is 50-80 cm.

3. A vortex built-in separator for a circulating fluidized bed boiler according to claim 1 or 2, characterized in that the separation chamber has an inner wall diameter length with a distance from the gas flow outlet of 3: (0.5-0.8), wherein the ratio of the air flow outlet spacing to the air flow inlet spacing is 1:1.

4. The cyclone separator for a circulating fluidized bed boiler of claim 1, wherein an inlet header is provided at an upper end of the left membrane wall, an upper header is provided at a lower end of the right membrane wall, a lower header is provided at an upper end of the lower membrane wall, a gap is provided between the inlet header and the right membrane wall and an air flow inlet is formed, a gap is provided between the upper header and the lower header and an air flow outlet is formed, and the inlet header, the upper header and the lower header are connected through a communication pipe.

5. The cyclone built-in separator for a circulating fluidized bed boiler according to claim 1, wherein a back wall of the boiler furnace is provided with a back wall water-cooled membrane wall, the back wall water-cooled membrane wall and the lower part of the left membrane water-cooled wall form a self-sealing channel, the self-sealing channel is communicated with the lower part of the return channel, and a blanking port is arranged at the bottom of the self-sealing channel and is communicated with the boiler furnace.

6. The cyclone separator for a circulating fluidized bed boiler of claim 5, wherein the bottom of the self-sealing passage is a porous structure to form a blanking port.

7. A cyclone built-in separator for a circulating fluidized bed boiler according to claim 1, wherein the width of the return channel gradually increases from top to bottom.

8. A cyclone built-in separator for a circulating fluidized bed boiler according to claim 1, wherein the left membrane water wall constituting a return channel is 45±2° to the vertical direction.

9. The cyclone built-in separator for a circulating fluidized bed boiler of claim 1, wherein the gas flow outlet is provided with a slag condensing pipe and a trough type separator along a flow direction of the flue gas.

10. A vortex built-in separator for a circulating fluidized bed boiler in accordance with claim 9, wherein the trough separators are vertically spaced apart and in a staggered array.