A device and method for separating flue gas in a grate-fired boiler

Abstract

The present application relates to the technical field of flue gas separation, and particularly discloses a flue gas separation device and method for a layer combustion boiler, which comprises a capture separation unit and a bag separation unit. The capture separation unit uses a capturing element to perform dynamic ash capture on flue gas entering a capture separation bin, thereby removing sticky large particles in advance and avoiding direct contact of the bag separation unit with easily adhering impurities, effectively preventing blockage and wear of the bag separation element. The capturing element continuously moves and periodically scrapes impurities, thereby achieving self-cleaning and automatic collection of impurities. The bag separation element is periodically back-flushed by a back-flushing element, thereby causing adhered dust to automatically fall off, so that multi-stage separation of impurities of different particle sizes in flue gas is achieved, flue gas dust content is effectively reduced, and ash deposition and corrosion of the convection flue are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flue gas separation, in particular to a flue gas separation device and method for a grate-fired boiler. BACKGROUND

[0002] At present, a bag filter is usually used to separate flue gas at the outlet of a furnace and a convection flue of a grate-fired boiler, however, the flue gas of the boiler contains sticky and large-particle ash, which is easy to directly block the pores of the bag filter, resulting in blocked flue gas flow, and the single filtering mechanism cannot effectively remove different particle sizes, especially sticky impurities, and it is difficult to completely remove the adhesion on the filter bag, and the sticky particles lack pretreatment, which not only increases the burden of the subsequent fine filtering unit, but also causes serious ash deposition and corrosion in the convection flue. SUMMARY

[0003] In order to overcome the above technical problems, the present application provides a flue gas separation device and method for a grate-fired boiler.

[0004] The purpose of the present application can be achieved by the following technical solutions:

[0005] A flue gas separation device for a grate-fired boiler, comprising:

[0006] A capture separation unit, comprising a first separation bin and a first ash bin connected to each other, the first separation bin is connected with an air inlet pipe on one side, and the top of the first separation bin is connected with an exhaust bin, the first separation bin is provided with a capture separation bin communicated with the exhaust bin, the capture separation bin is movably installed with a capture piece, and the bottom of the capture separation bin is connected with an ash discharge channel matched with the capture piece;

[0007] A bag separation unit, comprising a second separation bin and a second ash bin connected to each other, the second separation bin is provided with a transition pipe communicated with the exhaust bin on one side, the top of the second separation bin is provided with an air outlet pipe, the second separation bin is provided with a bag separation piece, and the second separation bin is provided with a blowback piece matched with the bag separation piece at the connection position of the second separation bin and the air outlet pipe.

[0008] As a further scheme of the present application: the capture separation bin comprises a bin body embedded in the first separation bin, the bin body is eccentrically provided with a capture cavity, the upper end of the capture cavity is provided with an air inlet communicated with the first separation bin, the side of the bin body away from the capture cavity is provided with a purification chamber, the upper end of the purification chamber is communicated with the exhaust bin, and the side wall of the capture cavity is provided with a side air duct communicated with the purification chamber.

[0009] As a further scheme of the present application: the exhaust bin comprises a wind cavity arranged above the first separation bin, one side of the wind cavity being communicated with the transition pipe; a connecting air duct communicated with the purification chamber is arranged at the bottom of the wind cavity, and a cover plate is arranged at the bottom of the connecting air duct close to the air inlet side.

[0010] As a further scheme of the present application: the trapping member comprises a rotating disc eccentrically arranged in the trapping cavity, a plurality of radial sliding cavities are arranged on the rotating disc in a circumferential direction, and a trapping plate is slidably arranged in the sliding cavity.

[0011] As a further scheme of the present application: the trapping and separating unit further comprises a driving member connected with the trapping member, the driving member comprises a driving motor fixedly arranged at the top of the wind cavity, a rotating shaft penetrating through the connecting air duct is connected with the output end of the driving motor, the lower end of the rotating shaft is fixedly connected with the rotating disc in a coaxial manner, and a fan blade arranged in the wind cavity and a spiral filter arranged in the connecting air duct are further arranged on the rotating shaft.

[0012] As a further scheme of the present application: the bag separation member comprises a support framework fixedly arranged in the second separation bin, a filter bag is arranged outside the support framework, an opening communicated with the air outlet pipe is arranged at the upper end of the filter bag, and the back blowing member is arranged at the opening.

[0013] As a further scheme of the present application: the back blowing member comprises an annular fixed plate fixedly arranged at the opening at the upper end of the filter bag, an annular air cavity is arranged in the inner side of the annular fixed plate, and a plurality of air injection ports facing the interior of the filter bag are arranged on the annular air cavity in a circumferential direction.

[0014] As a further scheme of the present application: the back blowing member further comprises an annular air bin arranged on the inner wall of the second separation bin, a movable annular frame is movably arranged between the annular fixed plate and the annular air bin, turbine blades extending into the air outlet pipe are arranged at the center of the movable annular frame, arc-shaped flow guides extending into the filter bag are arranged on the inner side of the movable annular frame, a plurality of notches are arranged on the outer side of the annular air cavity in a circumferential direction, a plurality of communication air ducts communicated with the annular air bin and the notches are arranged on the inner side of the movable annular frame in a circumferential direction, and a back blowing air pipe communicated with the annular air bin is arranged on the outer side of the second separation bin.

[0015] As a further scheme of the present application: the transition pipe is further provided with an intercepting member at the connection position with the second separation bin, the intercepting member comprises an intercepting plate fixedly arranged in the second separation bin, and a plurality of filter holes are arranged at the lower end of the intercepting plate.

[0016] The application further discloses a method for using the in-furnace flue gas separation device of the layer combustion boiler.

[0017] Step one: the flue gas enters the trapping and separating bin, and the impurities are dynamically intercepted and trapped by the trapping member;

[0018] Step two, the impurities attached to the trapping piece are automatically scraped off and fall into the first ash bucket through the ash discharge channel;

[0019] Step three, the preliminarily purified flue gas enters the bag separation unit, is finely filtered by the bag separation piece and intercepts dust;

[0020] Step four, the back flushing piece periodically pulses back to the bag separation piece, shakes off the dust on the surface and falls into the second ash bucket;

[0021] Step five, the purified clean flue gas is discharged from the gas outlet pipe.

[0022] The beneficial effects of the present application are as follows:

[0023] The present application adopts a two-stage separation structure, the trapping separation unit effectively traps viscous large-particle dust and ash in the flue gas by the movable trapping piece, and the bag separation unit finely filters small-particle ash, thereby realizing multi-stage separation of impurities of different particle sizes in the flue gas and effectively reducing the dust content of the flue gas;

[0024] The trapping separation unit uses the trapping piece to dynamically trap ash in the flue gas entering the trapping separation chamber, first removes viscous large particles, avoids direct contact of the bag separation unit with easily adhering impurities, effectively prevents blockage and wear of the bag separation piece, the trapping piece realizes self-cleaning and automatic collection of impurities by continuous movement and periodic scraping of impurities, the bag separation piece automatically falls off the adhered dust by periodic back flushing of the back flushing piece, effectively reduces the ash deposition and corrosion of the convection flue, and improves the heat exchange efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0025] The present application will be further described below with reference to the accompanying drawings.

[0026] Figure 1 It is a perspective view of a flue gas separation device for a layer combustion boiler according to the present application;

[0027] Figure 2 It is a perspective view of a flue gas separation device for a layer combustion boiler according to the present application from another angle;

[0028] Figure 3 It is a sectional view of a trapping separation unit in a flue gas separation device for a layer combustion boiler according to the present application;

[0029] Figure 4 It is a sectional view of an exhaust chamber and a trapping separation chamber in a flue gas separation device for a layer combustion boiler according to the present application;

[0030] Figure 5 It is a transverse sectional view of a trapping separation chamber and a trapping piece in a flue gas separation device for a layer combustion boiler according to the present application;

[0031] Figure 6 Figure 1 is a schematic diagram of a smoke flow direction in a capturing and separating unit of a furnace smoke separating device for a layer combustion boiler according to the present application;

[0032] Figure 7 Figure 2 is a sectional view of a bag type separating unit of a furnace smoke separating device for a layer combustion boiler according to the present application;

[0033] Figure 8 Figure 3 is a sectional view of the bag type separating unit from another perspective according to the present application; Figure 7 Figure 4 is an enlarged view of position A in Figure 3;

[0034] Figure 9 Figure 5 is an enlarged view of position B in Figure 3;

[0035] Figure 10 Figure 6 is an enlarged view of position C in Figure 3; Figure 9

[0036] Figure 7 is a schematic diagram of a capturing and separating unit according to the present application;

[0037] 100, capturing and separating unit; 110, first separating bin; 120, first ash hopper; 130, air inlet pipe; 140, air outlet bin; 141, air cavity; 142, connecting air duct; 143, cover plate; 150, capturing and separating bin; 151, bin body; 152, capturing cavity; 153, purifying chamber; 154, side air duct; 155, air inlet; 160, ash discharge channel; 170, capturing member; 171, rotating disc; 172, sliding cavity; 173, capturing plate; 180, driving member; 181, driving motor; 182, rotating shaft; 183, fan blade; 184, spiral filter piece;

[0038] 200, bag type separating unit; 210, second separating bin; 220, second ash hopper; 230, transition pipe; 240, air outlet pipe; 250, bag type separating member; 251, support framework; 252, filter bag; 260, back flushing member; 261, annular fixing plate; 262, annular air cavity; 263, air injection port; 264, annular air bin; 265, movable annular frame; 266, turbine blade; 267, communicating air passage; 268, notch; 269, arc-shaped flow guide cover; 2610, back flushing air pipe; 270, intercepting member; 271, intercepting plate; 272, filter hole. DETAILED DESCRIPTION

[0039] The subject matter described herein will now be discussed with reference to example implementations. It should be understood that the discussion of these implementations is merely meant to provide a better understanding of the subject matter described herein and can be changed in function and arrangement without departing from the scope of the present description. Various processes or components can be omitted, substituted, or added according to desired implementations. Additionally, features described with respect to some examples can be combined in other examples.​

[0040] Referring to Figure 1 and Figure 2 The application discloses a flue gas separation device for a layer combustion boiler, which comprises a capture separation unit 100 and a bag separation unit 200.

[0041] Referring to Figure 3 The capture separation unit 100 comprises a first separation bin 110 and a first ash bin 120 which are connected to each other, the first separation bin 110 is connected with an air inlet pipe 130 on one side, the first separation bin 110 is connected with an exhaust bin 140 on the top, the first separation bin 110 is provided with a capture separation bin 150 which is communicated with the exhaust bin 140, the capture separation bin 150 is movably provided with a capture piece 170, and the capture separation bin 150 is connected with an ash discharge channel 160 which is matched with the capture piece 170 on the bottom.

[0042] Referring to Figure 7 The bag separation unit 200 comprises a second separation bin 210 and a second ash bin 220 which are connected to each other, the second separation bin 210 is provided with a transition pipe 230 which is communicated with the exhaust bin 140 on one side, the second separation bin 210 is provided with an air outlet pipe 240 on the top, the second separation bin 210 is provided with a bag separation piece 250, and the second separation bin 210 is provided with a blowback piece 260 which is matched with the bag separation piece 250 at the joint with the air outlet pipe 240.

[0043] Specifically, the device is arranged between the hearth outlet of the layer combustion boiler and the convection flue inlet, the air inlet pipe 130 is connected with the hearth outlet, the air outlet pipe 240 is connected with the convection flue inlet, the flue gas in the hearth enters the first separation bin 110 through the air inlet pipe 130, the capture piece 170 continuously moves to capture the viscous large-particle dust and ash and other impurities in the flue gas during the process of passing through the capture separation bin 150, the flue gas after filtering the impurities flows upwards into the exhaust bin 140, and the impurities captured on the capture piece 170 are periodically scraped off, separated and fall into the first ash bin 120 through the ash discharge channel 160.

[0044] The flue gas after the first separation treatment of the capture separation unit 100 is discharged from the exhaust bin 140 and enters the second separation bin 210 through the transition pipe 230, the bag separation piece 250 in the second separation bin 210 is used to filter and intercept the small-particle ash and other impurities in the flue gas, the blowback piece 260 is used to periodically blow air into the bag separation piece 250 to make the dust intercepted outside the bag separation piece 250 periodically fall off and drop into the second ash bin 220 below, and the flue gas after the second purification passes through the bag separation piece 250 and flows upwards and finally flows into the convection flue inlet through the air outlet pipe 240.

[0045] It should be noted that the present application adopts a two-stage separation structure, the capturing and separating unit 100 effectively captures viscous large-particle dust and ash in flue gas through the movable capturing member 170, and the bag-type separating unit 200 finely filters small-particle ash, so that multi-stage separation of impurities of different particle sizes in flue gas is realized, and the dust content in flue gas is effectively reduced.

[0046] The capturing and separating unit 100 removes viscous large particles first, avoiding the direct contact of the bag-type separating unit 200 with the easily adhering impurities, effectively preventing the blocking and wear of the bag-type separating member 250; the capturing member 170 realizes self-cleaning and automatic collection of impurities through continuous movement and periodic removal of impurities; the bag-type separating member 250 makes the adhered dust automatically fall off through the periodic back blowing of the back blowing member 260, effectively reducing the ash deposition and corrosion of the convection flue, and improving the heat exchange efficiency.

[0047] In an embodiment, referring to Figure 4 and Figure 5 , the capturing and separating chamber 150 includes a chamber body 151 embedded in the first separating chamber 110, the chamber body 151 is eccentrically provided with a capturing cavity 152, the capturing cavity 152 is provided with an air inlet 155 at the upper end and in communication with the first separating chamber 110, the chamber body 151 is provided with a purification chamber 153 at the side away from the capturing cavity 152, the purification chamber 153 is in communication with the exhaust chamber 140 at the upper end, and the side wall of the capturing cavity 152 is provided with a side air duct 154 in communication with the purification chamber 153;

[0048] Specifically, referring to Figure 6 , the dust-containing flue gas entering the first separating chamber 110 from the air inlet pipe 130 flows downward into the capturing cavity 152 through the air inlet 155, the capturing member 170 in the capturing cavity 152 continuously captures the particulate impurities in the dust-containing flue gas, then the flue gas separated from the impurities enters the purification chamber 153 through the side air duct 154, and finally the flue gas in the purification chamber 153 flows upward into the exhaust chamber 140, while the impurities on the capturing member 170 fall into the first ash bucket 120 through the ash discharge channel 160.

[0049] It should be noted that by eccentrically arranging the capturing cavity 152 and designing it as a flue gas downward path, the large-particle viscous impurities in the flue gas are continuously captured by the capturing member 170 in the process, realizing the pre-enrichment and preliminary separation of the impurities; after the flue gas completes the impurity capturing in the capturing cavity 152, the clean gas flow enters the purification chamber 153 through the side air duct 154, and finally is discharged upward, physically separating the dirty capturing area from the clean exhaust area, effectively preventing the settled or captured dust from being carried away again due to direct flow scouring, and at the same time ensuring the cleanliness of the flue gas after primary separation.

[0050] Further, referring to Figure 4 andFigure 6 The exhaust bin 140 includes a wind cavity 141 arranged above the first separation bin 110, one side of the wind cavity 141 being communicated with the transition pipe 230; the bottom of the wind cavity 141 is provided with a connecting air duct 142 communicated with the purification chamber 153, and the bottom of the connecting air duct 142 is provided with a cover plate 143 near one side of the air inlet 155;

[0051] Specifically, the primary separated flue gas flows into the connecting air duct 142 upward, and then reaches the wind cavity 141, and part of the impurities continue to settle into the purification chamber 153 during the rising of the flue gas through the connecting air duct 142.

[0052] It is worth noting that by arranging the connecting air duct 142, a vertical rising path is provided for the flue gas from the purification chamber 153, during which the flow rate of the flue gas changes, providing a secondary settling opportunity for the small amount of residual particulate matter carried therein, so that it falls back to the bottom of the purification chamber 153 under the action of gravity, further reducing the dust load entering the subsequent bag separation unit 200;

[0053] The wind cavity 141 serves as a gas collection and buffering space, which can balance and stabilize the airflow from the connecting air duct 142, and then stably deliver it to the transition pipe 230, effectively avoiding the direct impact of the airflow or the formation of uneven distribution between different channels, ensuring the stability of the airflow dynamics of the entire system;

[0054] The cover plate 143 is arranged at the bottom of the connecting air duct 142 near one side of the air inlet 155, which isolates the inlet area of the dirty trapping chamber 152 from the connecting air duct 142, thereby preventing the untreated dust-containing flue gas from directly entering the connecting air duct 142, ensuring that all flue gas passes through a complete trapping and separation process, thereby ensuring the reliability of the primary separation effect.

[0055] Further, referring to Figure 5 The trapping member 170 includes a rotating disc 171 eccentrically arranged in the trapping chamber 152, a plurality of radial sliding cavities 172 are arranged on the rotating disc 171 in the circumferential direction, and a trapping plate 173 is slidably arranged in the sliding cavity 172;

[0056] Specifically, during the flue gas flowing through the capture cavity 152, the rotating disc 171 continuously rotates, and when the sliding cavity 172 opening of the rotating disc 171 rotates to the side away from the purification chamber 153, the interval between the rotating disc 171 sidewall and the inner wall of the capture cavity 152 gradually increases at this time, so that the capture plate 173 in the sliding cavity 172 is thrown out until the capture plate 173 extension end abuts against the inner wall of the capture cavity 152, and the captured plate 173 is used to intercept the dust-containing flue gas flowing through the capture cavity 152, thereby capturing the sticky ash in the flue gas, and then the flue gas enters the purification chamber 153 from the side air duct 154; with the continuous rotation of the rotating disc 171, the capture plate 173 carrying the ash gradually retracts into the corresponding sliding cavity 172 under the restriction of the capture cavity 152, and at this time the capture plate 173 is just rotated to above the ash discharge passage 160, and the capture plate 173 automatically scrapes off the captured ash during the process of gradually retracting into the sliding cavity 172, and then the ash falls into the ash discharge passage 160 and is discharged into the first ash bucket 120.

[0057] It should be noted that the continuous rotation of the rotating disc 171 and the radial sliding of the capture plate 173 are combined, and when the capture plate 173 is thrown out and abuts against the inner wall of the capture cavity 152, a continuously moving filter barrier is formed, thereby actively intercepting the sticky ash in the flue gas, and the capture plate 173 automatically retracts into the sliding cavity 172 under the constraint of the wall surface of the capture cavity 152 when it rotates to above the ash discharge passage 160, and synchronously accurately scrapes off the ash adhered thereto; the capture and ash removal are orderly carried out in two different spatial positions without interference, which not only ensures the continuous purification capacity, but also avoids the secondary pollution of the capture process by the ash removal, greatly optimizing the efficiency and reliability of the separation process.

[0058] In addition, please refer to Figure 2 and Figure 3 , the capture separation unit 100 further comprises a driving member 180 connected with the capture member 170, the driving member 180 comprises a driving motor 181 fixedly installed on the top of the air cavity 141, the output end of the driving motor 181 is connected with a rotating shaft 182 penetrating through the connecting air duct 142, the lower end of the rotating shaft 182 is fixedly connected with the rotating disc 171 in a same axis, and the rotating shaft 182 is further provided with fan blades 183 located in the air cavity 141 and spiral filter pieces 184 located in the connecting air duct 142;

[0059] Specifically, by driving the motor 181 to continuously rotate the rotating shaft 182, the capturing member 170 can be continuously moved to continuously capture the ash and impurities in the flue gas in the capturing cavity 152; during rotation, the rotating shaft 182 can also drive the fan blades 183 in the air cavity 141 to rotate, thereby increasing the flow rate of the rising flue gas and promoting the circulation of the flue gas; in addition, the rotating shaft 182 can also drive the spiral filter piece 184 in the connecting air duct 142 to rotate circumferentially, and the spiral filter piece 184 in spiral motion can further intercept the rising flue gas in the connecting air duct 142, and the spiral filter piece 184 can effectively increase the contact area with the flue gas, thereby improving the dynamic separation effect of the flue gas.

[0060] It is worth noting that the fan blades 183 arranged in the air cavity 141 form an internal induced draft fan when the rotating shaft 182 rotates, which can actively increase the flow rate of the rising flue gas, effectively overcome the system flow resistance, and ensure smooth circulation of the flue gas in the entire device, preventing airflow stagnation or blockage that may occur in complex flow channels.

[0061] The spiral filter piece 184 is arranged in the connecting air duct 142, and when it rotates, it forms a dynamic centrifugal filter field. When the residual particulate matter in the rising flue gas hits the rotating spiral blades, the flue gas purification path and the contact area are increased, thereby further reducing the dust concentration entering the bag-type separation member 250.

[0062] In yet another embodiment, please refer to Figure 7 and Figure 8 The bag-type separation member 250 includes a support framework 251 fixed in the second separation chamber 210, and a filter bag 252 is sleeved outside the support framework 251, the upper end of the filter bag 252 is provided with an opening connected with the gas outlet pipe 240, and the blowback member 260 is arranged at the opening.

[0063] Specifically, the flue gas entering the second separation chamber 210 through the transition pipe 230 passes through the filter bag 252 from the outside and enters the inside of the filter bag 252, and the dust particles in the flue gas are filtered and intercepted by the filter bag 252, and then the purified flue gas rises along the filter bag 252 and enters the gas outlet pipe 240 through the opening; the blowback member 260 periodically inflates and blows back from the opening into the filter bag 252, so that the filter bag 252 intermittently expands and oscillates outward, and the dust adhered to the outside of the filter bag 252 falls into the second ash bucket 220 below.

[0064] It should be noted that the flow channel design of entering from the outside and exiting from the inside makes the flue gas pass through the filter bag 252 from the outside, and the filter bag 252 with a small pore size is used to perform secondary fine filtration on the flue gas after the pre-treatment, effectively intercepting submicron small particle dust and ensuring the cleanliness of the discharged flue gas.

[0065] The back-blowing part 260 is directly integrated at the opening of the upper end of the filter bag 252. High-pressure gas is instantaneously injected into the inside of the filter bag 252 from the opening, so that the filter bag 252 generates high-frequency oscillation and expands outward, which can completely and uniformly shake off the dust layer adhered to the outer surface of the filter bag 252, and effectively restore the air permeability and filtering performance of the filter bag 252.

[0066] The support framework 251 provides a stable support frame for the soft filter bag 252, prevents the filter bag 252 from being sucked under the action of negative pressure, and ensures the effective filtering area. At the same time, the combination of the rigid framework and the flexible filter bag 252 makes the oscillation of the filter bag 252 more violent and sufficient during back-blowing, which greatly improves the thoroughness of dust removal.

[0067] Further, referring to Figure 8 and Figure 10 , the back-blowing part 260 includes a ring-shaped fixed plate 261 fixed at the opening of the upper end of the filter bag 252. A ring-shaped air cavity 262 is formed in the inner side of the ring-shaped fixed plate 261. A plurality of air injection ports 263 facing the inside of the filter bag 252 are formed in the circumferential direction of the ring-shaped air cavity 262.

[0068] Specifically, the ring-shaped air cavity 262 is periodically inflated by an external air source, so that high-pressure gas is periodically filled into the filter bag 252 through the air injection ports 263, so that the air pressure in the filter bag 252 is instantaneously increased, thereby realizing the air inflation backflushing of the filter bag 252.

[0069] Further, referring to Figure 8 , Figure 9 and Figure 10 , the back-blowing part 260 further includes a ring-shaped air chamber 264 arranged on the inner wall of the second separation bin 210. The ring-shaped air chamber 264 and the ring-shaped fixed plate 261 are rotatably embedded with a movable ring-shaped frame 265. The movable ring-shaped frame 265 is provided with a turbine blade 266 extending into the air outlet pipe 240 at the center. The inner side of the movable ring-shaped frame 265 is provided with an arc-shaped flow guide cover 269 extending into the filter bag 252. A plurality of notches 268 are formed in the circumferential direction of the outer side of the ring-shaped air cavity 262. A plurality of communication air channels 267 are formed in the circumferential direction of the inner side of the movable ring-shaped frame 265, which are in communication with the ring-shaped air chamber 264 and the notches 268. The outer side of the second separation bin 210 is provided with a back-blowing air pipe 2610 in communication with the ring-shaped air chamber 264.

[0070] Specifically, by continuously blowing the external gas source into the annular air chamber 264 through the blowback pipe 2610, when the flue gas flows upward through the air outlet pipe 240, the turbine blades 266 and the movable annular frame 265 can be continuously rotated, so that the communication air duct 267 in the movable annular frame 265 is intermittently communicated with the slot 268. When the communication air duct 267 is communicated with the slot 268, the high-pressure gas flow in the annular air chamber 264 can enter the annular air cavity 262 through the communication air duct 267 and the slot 268 in sequence, and finally the high-pressure gas flow is sprayed out from the air jet 263. The high-pressure gas flow is guided by the arc-shaped flow guide 269, so that the high-pressure gas flow is quickly filled into the filter bag 252.

[0071] It should be noted that the system itself uses the flowing flue gas as a power source, and the rising purified flue gas drives the turbine blades 266 to rotate, thereby driving the entire movable annular frame 265 to rotate;

[0072] Through the continuous rotation of the movable annular frame 265, the communication air duct 267 on it is periodically aligned with the slot 268 on the annular fixed plate 261, so that the continuous gas pressure in the annular air chamber 264 is converted into intermittent pulse gas supply to the annular air cavity 262. The pulse gas flow is sprayed out through the air jet 263, which can produce an instantaneous strong impact on the filter bag 252;

[0073] The arc-shaped flow guide 269 arranged on the inner side of the movable annular frame 265 and extending into the filter bag can guide the radial high-speed gas flow into a downward directional jet, so that the high-pressure gas is more deeply filled into the bottom of the filter bag 252, ensuring that the entire filter bag length range can be uniformly and powerfully cleaned, effectively improving the uniformity and efficiency of cleaning. Since the pulse blowback is completed instantaneously, it will not have a great impact on the normal operation of the system, ensuring the continuity and stability of the flue gas purification process.

[0074] In addition, please refer to Figure 7 and Figure 9 , the transition pipe 230 is connected with the second separation chamber 210, and the transition pipe 230 is connected with the second separation chamber 210. The intercepting piece 270 is further provided at the connection position of the second separation chamber 210, the intercepting piece 270 comprises an intercepting plate 271 fixed in the second separation chamber 210, and a plurality of filtering holes 272 are formed in the lower end of the intercepting plate 271.

[0075] Specifically, when the flue gas passes through the transition pipe 230 and enters the second separation chamber 210, the flue gas will be intercepted by the intercepting plate 271, so that the flue gas spreads around. At the same time, when the flue gas passes through the filtering holes 272 at the lower end of the intercepting plate 271, part of the dust in the flue gas can be pre-intercepted and fall into the second hopper 220 below.

[0076] Notably, the intercepting plate 271 directly blocks the main flow of flue gas, forcing the flue gas flow to suddenly drop and change direction, and some larger particles in the flue gas that fail to timely turn due to inertia will directly impact the intercepting plate 271 and settle, effectively reducing the dust handling load of the subsequent bag separation element 250;

[0077] The intercepting plate 271 forces the flue gas to spread around, dispersing the originally possible concentrated jet flow, so that the flue gas is more evenly distributed to the entire surface of the filter bag 252, avoiding the blockage caused by excessive local airflow, thereby improving the overall filtration efficiency of the bag separation unit 200.

[0078] The present application also discloses a method for using the in-furnace flue gas separation device for a layer combustion boiler, comprising the following steps:

[0079] Step one, the flue gas enters the capture separation bin 150 and is dynamically intercepted and captured by the capturing element 170;

[0080] Step two, the impurities attached to the capturing element 170 are automatically scraped off and fall into the first hopper 120 for collection through the ash discharge channel 160;

[0081] Step three, the preliminarily purified flue gas enters the bag separation unit 200 and is finely filtered and intercepted by the bag separation element 250;

[0082] Step four, the back-blowing element 260 periodically pulses back-blowing into the bag separation element 250, shaking off the dust on the surface and falling into the second hopper 220;

[0083] Step five, the purified clean flue gas is discharged from the gas outlet pipe 240.

[0084] The specific embodiments of the present application are described above, but the present application is not limited to the above specific embodiments, and the above specific embodiments are only illustrative and not limiting, and those skilled in the art can make many forms under the inspiration of the present application, which all belong to the protection of the present application.

Claims

1. A device for separating flue gas in a grate-fired boiler, characterized in that The utility model relates to a dust catcher and bag separation unit for dust removal, which comprises a first separation bin (110) and a first dust hopper (120) connected with each other, a gas inlet pipe (130) connected to one side of the first separation bin (110), a gas exhaust bin (140) connected to the top of the first separation bin (110), a dust catcher separation bin (150) arranged in the first separation bin (110) and communicated with the gas exhaust bin (140), a dust catcher (170) movably arranged in the dust catcher separation bin (150), and a dust discharge channel (160) connected to the bottom of the dust catcher separation bin (150) and matched with the dust catcher (170). The utility model relates to a dust catcher and bag separation unit for dust removal, which comprises a second separation bin (210) and a second dust hopper (220) connected with each other, a transition pipe (230) arranged on one side of the second separation bin (210) and communicated with the gas exhaust bin (140), a gas outlet pipe (240) arranged on the top of the second separation bin (210), a bag separation piece (250) arranged in the second separation bin (210), and a back flushing piece (260) arranged at the joint of the second separation bin (210) and the gas outlet pipe (240) and matched with the bag separation piece (250). The dust catcher (170) comprises a rotating disc (171) eccentrically arranged in the dust catcher separation bin (150), a plurality of radial sliding cavities (172) are formed in the rotating disc (171), and a dust catcher plate (173) is slidably arranged in the sliding cavity (172). The dust catcher separation bin (150) comprises a bin body (151) arranged in the first separation bin (110), a dust catcher cavity (152) eccentrically arranged in the bin body (151), an air inlet (155) formed in the upper end of the dust catcher cavity (152) and communicated with the first separation bin (110), a purification chamber (153) formed on the side of the bin body (151) away from the dust catcher cavity (152), the upper end of the purification chamber (153) communicated with the gas exhaust bin (140), and a side air duct (154) formed in the side wall of the dust catcher cavity (152) and communicated with the purification chamber (153). The gas exhaust bin (140) comprises an air cavity (141) arranged above the first separation bin (110), the air cavity (141) communicated with the transition pipe (230) on one side, and a connecting air duct (142) arranged at the bottom of the air cavity (141) and communicated with the purification chamber (153), wherein a cover plate (143) is arranged on the side of the connecting air duct (142) close to the air inlet (155). The dust catcher separation unit (100) further comprises a driving piece (180) connected with the dust catcher (170), the driving piece (180) comprises a driving motor (181) fixedly arranged at the top of the air cavity (141), a rotating shaft (182) penetrating through the connecting air duct (142) and connected with the output end of the driving motor (181), the lower end of the rotating shaft (182) coaxially fixedly connected with the dust catcher (170), and a fan blade (183) arranged in the air cavity (141) and a spiral filter piece (184) arranged in the connecting air duct (142) are further arranged on the rotating shaft (182).

2. A device for separating flue gases in a grate-fired boiler according to claim 1, characterized in that ​ 3. A device for separating flue gases in a grate-fired boiler according to claim 1, characterized in that The bag type separation piece (250) comprises a supporting framework (251) fixed in the second separation bin (210), and a filter bag (252) is sleeved outside the supporting framework (251), and an opening is arranged at the upper end of the filter bag (252) and connected with the air outlet pipe (240), and the back blowing piece (260) is arranged at the opening.

4. A device for separating flue gases in a grate-fired boiler according to claim 3, characterized in that The back blowing piece (260) comprises a ring-shaped fixed plate (261) fixed at the opening of the upper end of the filter bag (252), a ring-shaped air cavity (262) is formed in the inner side of the ring-shaped fixed plate (261), and a plurality of air injection ports (263) are formed in the circumferential direction of the ring-shaped air cavity (262) and face the inside of the filter bag (252).

5. A device for separating flue gases in a grate-fired boiler according to claim 4, characterized in that The back blowing piece (260) further comprises a ring-shaped air bin (264) arranged on the inner wall of the second separation bin (210), a movable ring-shaped frame (265) is rotatably arranged between the ring-shaped air bin (264) and the ring-shaped fixed plate (261), a turbine blade (266) is arranged at the center of the movable ring-shaped frame (265) and extends into the air outlet pipe (240), an arc-shaped flow guide cover (269) is arranged on the inner side of the movable ring-shaped frame (265) and extends into the filter bag (252), a plurality of notches (268) are formed in the outer side of the ring-shaped air cavity (262) in the circumferential direction, a plurality of communication air channels (267) are formed in the inner side of the movable ring-shaped frame (265) in the circumferential direction and communicate the ring-shaped air bin (264) and the notches (268), and a back blowing air pipe (2610) is arranged on the outer side of the second separation bin (210) and communicates with the ring-shaped air bin (264).

6. A device for separating flue gases in a grate-fired boiler according to claim 3, characterized in that The transition pipe (230) is further provided with an intercepting piece (270) at the connection position with the second separation bin (210), the intercepting piece (270) comprises an intercepting plate (271) fixed in the second separation bin (210), and a plurality of filter holes (272) are formed in the lower end of the intercepting plate (271).

7. A method of using the flue gas separating device for a grate-fired boiler according to any one of claims 1 - 6, characterized in that, The method comprises the following steps: Step one, the flue gas enters the trapping separation bin (150), and the impurities are dynamically intercepted and trapped by the trapping piece (170); Step two, the impurities attached to the trapping piece (170) are automatically scraped off and fall into the first ash bucket (120) for collection through the ash discharge channel (160); Step three, the preliminarily purified flue gas enters the bag type separation unit (200), and the bag type separation piece (250) is used for fine filtering and intercepting dust; Step four, the back blowing piece (260) periodically performs pulse back blowing to the inside of the bag type separation piece (250), shakes off the dust on the surface of the bag type separation piece (250) and falls into the second ash bucket (220); Step five, the purified clean flue gas is discharged from the air outlet pipe (240).

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