CN109289374B

CN109289374B - Ceramic filter tube

Info

Publication number: CN109289374B
Application number: CN201811214418.7A
Authority: CN
Inventors: 张建飞; 元西方; 鲁喜平; 赵峰燕
Original assignee: Bestter Group Co ltd
Current assignee: Bestter Group Co ltd
Priority date: 2018-10-18
Filing date: 2018-10-18
Publication date: 2021-04-13
Anticipated expiration: 2038-10-18
Also published as: CN109289374A

Abstract

The invention relates to a ceramic filter tube, which comprises a tube body of ceramic fibers for filtering, wherein the inside of the tube body and the outside of the tube body realize bidirectional air communication through a plurality of air holes on the tube wall of the tube body; in the filtering state, the filtering airflow flows in from the pipe wall and flows out from the opening end; when in the backwashing state, backwashing air flows in from the opening end and flows out from the pipe wall; the ceramic filter tube also comprises a rotating shaft at least partially arranged in the hollow cavity, and the rotating shaft is driven by reverse washing airflow during reverse washing; and at least part of the turbulence blades are arranged in the hollow cavity and used for disturbing the reverse washing airflow entering the hollow cavity so as to ensure that dust cakes attached to the outside of the pipe wall are peeled off under the condition of the disturbed reverse washing airflow, and the turbulence blades and the rotating shaft rotate integrally. The invention can ensure that the dust cake attached to the outer wall of the ceramic filter pipe is more thoroughly peeled off during reverse cleaning operation.

Description

Ceramic filter tube

Technical Field

The invention relates to the field of treatment of high-temperature waste gas containing dust, in particular to a ceramic filter tube.

Background

Air pollution in China is very serious, and waste gas of most factories contains a large amount of dust. Although most factories are currently provided with dust removing devices such as an electric dust remover, a bag-type dust remover, an electric bag composite dust remover, a mechanical dust remover and the like, the dust removing devices have different characteristics and application ranges. The electric dust collector has high investment cost, large occupied area and low trapping efficiency on dust with the particle size less than 5 mu m. The mechanical dust remover comprises a gravity settling chamber, an inertial dust remover and a cyclone dust remover, wherein the two dust removers can only remove large particles with the particle size of more than 50 microns, and the cyclone dust remover has low collection efficiency on dust with the particle size of less than 10 microns. Because of the temperature limitation of the filter bag, the bag-type dust collector and the electric bag composite dust collector are not suitable for removing dust of high-temperature flue gas (more than 300 ℃). For dust removal of high-temperature flue gas (more than 300 ℃), a ceramic tube filter dust remover is an ideal choice. The ceramic tube filter adopts the micropore ceramic tube as the filtering material, and the micropore ceramic tube has the advantages of high temperature resistance, corrosion resistance, relatively low cost, long service life and the like, and is widely applied to industries such as chemical industry, petroleum, metallurgy, electric power and the like. Compared with the conventional technologies such as cyclone dust removal and electrostatic dust removal, the technology is more suitable for removing dust in high-temperature and corrosive industrial gas. The technology requires that the core ceramic filter material has the advantages of excellent thermal stability, high dust removal efficiency and good corrosion resistance, can adapt to extremely high working temperature, and has the dust removal mechanism that when dust-containing air flows through the dust removal filter tube, dust is blocked on the outer wall of the ceramic filter tube through inertial collision, interception and diffusion, so that the purpose of gas-solid separation is achieved.

For example, chinese patent publication No. CN207102143U discloses a high-temperature gas filtering device, which includes a housing, a partition board is disposed in the housing, the partition board divides the housing into an upper clean gas chamber and a lower dust-containing gas chamber, an air outlet pipe communicated with the clean gas chamber is disposed at the upper end of the housing, an air inlet pipe communicated with the dust-containing gas chamber is disposed on the side wall of the lower end of the housing, and a sealing filtering device is disposed at one end of the air outlet pipe in the clean gas chamber; the partition board is provided with a plurality of through holes, ceramic fiber filter pipes are sleeved in the through holes, one ends of the ceramic fiber filter pipes are plugged, the other ends of the ceramic fiber filter pipes are provided with openings, one ends of the ceramic fiber filter pipes which are plugged extend into the dust-containing gas cavity through the through holes, the ends of the ceramic fiber filter pipes which are provided with the openings are arranged in the clean gas cavity, and back-blowing pipelines are respectively and correspondingly arranged right above the openings of the ceramic fiber filter pipes; the utility model discloses dust collection efficiency is high, and the operation is stable, effectively reduces the dust and in the intraductal deposit of filter, extension filter tube life.

For another example, chinese patent publication No. CN107670428A discloses a filter tube suitable for high temperature dust-containing flue gas, the top of the filter tube body is provided with a ceramic fiber plate cover, a preheating outlet pipe is arranged in the middle of the ceramic fiber plate cover, a waste gas burning chamber is arranged inside the preheating outlet pipe, the top of the preheating outlet pipe is provided with an air suction opening, both sides of the upper end inside the filter tube body are connected with a ceramic fiber blanket, a ceramic fiber sleeve is arranged inside the filter tube body, the ceramic fiber sleeve is located below the ceramic fiber blanket, a plurality of dust particles are arranged around the ceramic fiber sleeve, and the bottom of the filter tube body is provided with a hot air flue gas inlet.

However, after the ceramic filter tube is used for a period of time, dust cakes can be formed on the outer surface of the ceramic filter tube, so that part of air holes are blocked, and the filtering efficiency is reduced. At present, as mentioned in the above two patent documents, the dust cake can be peeled off by means of reverse blowing, such as directional pulse cleaning, however, the above two patents have problems that the dust cake on the surface is not peeled off thoroughly due to the uniform flow rate of the reverse washing air flow and uniform air pressure change during reverse blowing, and further improvement is needed. Moreover, because the existing ceramic filter tube is long, for example, 2 to 4 meters long, and most of the airflow flows out from the part close to the air inlet for reverse blowing, dust cakes accumulated on the part of the airflow farther away from the air inlet for reverse blowing are not easy to be removed completely, and the filtering efficiency is affected.

Therefore, there is a strong need for improvement of the existing ceramic filter tube to more thoroughly peel off the dust cake attached to the outer wall of the ceramic filter tube during the reverse cleaning operation.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a ceramic filter tube, which creatively introduces turbulence blades into the tube body of the ceramic filter tube so as to lead the dust cake attached to the outside of the tube wall to be peeled off under the condition of turbulent reverse washing airflow, and lead the dust cake attached to the outer wall of the ceramic filter tube to be more thoroughly removed during the reverse washing operation. Moreover, the spoiler blades are driven by the reverse washing air flow, a driving device is not required to be additionally installed, the structure can be simplified, and the design, manufacturing and maintenance costs are reduced under the condition that the structure of the pipe body is not required to be greatly changed or even not required to be changed.

According to one aspect of the invention, a ceramic filter tube is disclosed, which comprises a tube body of ceramic fibers for filtering, wherein the inside of the tube body and the outside of the tube body realize bidirectional air communication through a plurality of air holes on the tube wall of the tube body, the tube body is provided with a hollow cavity, and only one end of the tube body is provided with an opening end communicated with the hollow cavity; the ceramic filter tube also comprises a rotating shaft at least partially arranged in the hollow cavity, and the rotating shaft is driven by the reverse washing airflow during reverse washing; and turbulence blades at least partially arranged in the hollow cavity and used for disturbing the reverse washing airflow entering the hollow cavity so as to make dust cakes attached to the outside of the pipe wall peel off under the condition of disturbed reverse washing airflow, wherein the turbulence blades and the rotating shaft rotate integrally; wherein, in the filtering state, the filtering airflow flows in from the pipe wall and flows out from the opening end; in the backwashing state, backwashing air flows in from the opening end and flows out from the pipe wall. As mentioned in the background, the prior art merely cleans the ceramic filter tubes by reverse gas flow, and upon application of a reverse pulse, the dust cake peels off the tube wall to effect cleaning, but the effectiveness of this cleaning operation is to be further enhanced. Therefore, the turbulent flow blades are arranged in the pipe body, so that the reverse washing airflow is disturbed before flowing out of the pipe wall, and the external dust cake can be more effectively and thoroughly peeled off under the condition of disturbed flow. Moreover, the spoiler blade setting has a plurality of beneficial effects in the body, includes at least: firstly, the reverse washing airflow flows out from the inside to the outside, the reverse washing airflow acts on the dust cake when the external turbulence is generated, and the external turbulence has little help to peel off the dust cake, so the effect achieved by the internal turbulence is better; its two, the setting can make the size of vortex blade in the body than set up externally littleer, can material saving, its three, sets up the influence that makes the vortex blade avoid pending waste gas in the body, improves life, and its four sets up the installation and dismantlement of being more convenient for in the body, and its five sets up like this and need not to change original body structure. While in the filtration state, a filtration gas stream flows in from the tube wall and out from the open end; when the reverse washing device is in a reverse washing state, reverse washing airflow flows in from the opening end and flows out from the pipe wall, so that dust cakes are formed on the outer wall of the pipe body, and the turbulence blades cannot be influenced by waste gas to be treated.

According to a preferred embodiment, the spoiler blade does not contact with the inner wall of the pipe body while rotating. Because the dust cake is gathered outside the pipe wall, the turbulence blades do not need to be contacted with the inner wall of the pipe body in the rotating process. So not only can be that the vortex blade rotates more smoothly, improves the vortex effect, can also reduce the damage of vortex blade to the body, improves the life of body and vortex blade, in addition, under the condition that the vortex blade does not contact with the inner wall of body, the air current of vortex blade vortex mixes in the back and the body after partly backwash air current flows down from the clearance between pipe wall and the vortex blade, further promotes the vortex degree for it is better to clear away the effect. And when the filter is used for filtering, a part of filtering airflow can flow upwards to the opening end from the gap between the pipe wall and the turbulence blades, so that the influence of the turbulence blades on the filtering airflow is reduced.

According to a preferred embodiment, the rotating shaft is at least partially inserted into the tube body from the open end and is mounted on the tube body through an insertion part tightly matched with the inner wall of the tube body, a through hole for communicating the hollow cavity with the outside is formed in the insertion part, the upper part of the rotating shaft is pivotally connected to the insertion part through a first bearing, at least one supporting part pivotally connected to the rotating shaft is further arranged on the rotating shaft, after the supporting part is mounted in place, the outer wall of the supporting part can abut against the inner wall of the tube body in a point contact mode through a plurality of protruding parts to keep the rotating shaft stable, and the supporting part is pivotally connected with the rotating shaft through at least one second bearing. If the outer wall of the support part abuts against the inner wall of the pipe body in a surface contact manner, the air holes in the area can be blocked by a large area, and the filtering and backwashing operation is influenced. Through the mode, the invention at least has the beneficial effect that the backwashing and the filtering operation are not influenced in the process of keeping the rotating shaft stable.

According to a preferred embodiment, the spindle is arranged in such a way that it can only be driven by the backwash air stream, whereas the filtration air stream cannot drive the spindle in rotation. Because the vortex blade rotates along with the rotating shaft, when filtering, if the rotating shaft still can be driven by the filtering air flow, the vortex blade also can rotate, and then a fluctuating air flow condition is formed outside the pipe wall, and dust is influenced to a certain extent to be attached to the pipe wall to form a dust cake. Therefore, in this way, the invention can reduce the influence of the turbolator blade on the dust adhesion to form the dust cake.

According to a preferred embodiment, the rotation of the shaft is arranged in such a way that it can be driven only by the backwash air stream and the filtration air stream cannot drive the rotation of the shaft by one of the following means: by providing at least one of the first bearing and the second bearing as a one-way bearing and the at least one-way bearing is arranged to only allow rotation of the rotating shaft in a first rotational direction; providing at least one damping element capable of providing rotational damping by the shaft, and the at least one damping element is configured to: providing no rotational damping in a first rotational direction and providing rotational damping in a direction opposite the first rotational direction, the rotational damping being sized such that the filtered air flow is unable to propel the rotating shaft; and by providing at least one ratchet mechanism arranged to only allow rotation of the shaft in a first rotational direction; wherein the first rotation direction is a direction in which the reverse washing air flow drives the rotation shaft to rotate.

According to a preferred embodiment, the rotating shaft is a hollow shaft, the upper end of the rotating shaft extends out of the open end, at least one first vent hole is formed in the position, above the middle part of the rotating shaft, which extends out of the open end, and a plurality of second vent holes are formed in the middle part and below the rotating shaft so that part of reverse washing airflow is directly guided out of the open end to flow out of the second vent holes through the hollow part of the rotating shaft during reverse washing.

According to a preferred embodiment, the plurality of second ventilation holes are arranged at intervals between the middle part and the lower end of the rotating shaft, and the connecting line of the central points of the second ventilation holes is positioned on a straight line, and the plurality of second ventilation holes are arranged in such a way that the opening of the second ventilation hole closer to the opening end is smaller.

According to a preferred embodiment, the shaft is driven by the force exerted by the backwash air flow on the spoiler blades and/or by the force exerted by the backwash air flow on the driving blades independently of the spoiler blades.

According to a preferred embodiment, the outer wall of the tubular body between the bottom and the open end is tapered and arranged in such a way that the diameter of the outer wall gradually increases from the bottom to the open end of the tubular body. By this way, the invention has at least the following beneficial effects: the drawing die of being convenient for when making the body through the mould can not influence the dust and attach and form the dirt cake on the outer wall, in addition, also more be favorable to peeling off of dirt cake during backwashing for backwashing efficiency is higher and clear away the dirt cake on the outer wall more thoroughly.

According to another aspect of the invention, a ceramic filter tube is disclosed, which comprises a tube body for filtering ceramic fibers, wherein the inside of the tube body and the outside of the tube body realize bidirectional air communication through a plurality of air holes on the tube wall of the tube body, and the ceramic filter tube comprises turbulence blades which are at least partially arranged in a hollow cavity of the tube body and are used for performing turbulence on backwash airflow entering the hollow cavity so that dust cakes attached to the outside of the tube wall are peeled off under the turbulent backwash airflow.

Drawings

FIG. 1 is a schematic external structural view of a preferred embodiment of a ceramic filter tube;

FIG. 2 is a schematic view in section and partially enlarged of a preferred embodiment of a ceramic filter tube;

FIG. 3 is a schematic structural view of a preferred embodiment of a spoiler blade and a rotating shaft;

FIG. 4 is a schematic structural view of another preferred embodiment of a spoiler blade; and

FIG. 5 is a schematic structural view of a preferred embodiment of a spoiler blade and a driving blade.

List of reference numerals

100: the pipe body 110: a hollow cavity 120: open end

130: tube wall 140: mounting flange 200: rotating shaft

300: the spoiler blade 410: the inserting part 420: supporting part

510: first bearing 520: second bearing 610: the first vent hole

620: second vent hole 700: driving blade

Detailed Description

This is described in detail below with reference to figures 1, 2, 3, 4 and 5.

In the description of the present invention, it is to be understood that, if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are used for indicating the orientation or positional relationship indicated based on the drawings, they are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it is also to be understood that the terms "first," "second," and the like, if any, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, the term "plurality", if any, means two or more unless specifically limited otherwise.

In the description of the present invention, it should be further understood that the terms "mounting," "connecting," "fixing," and the like are used in a broad sense, and for example, the terms "mounting," "connecting," "fixing," and the like may be fixed, detachable, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. To one of ordinary skill in the art, the specific meaning of the above terms in the present invention can be understood as appropriate, unless explicitly stated and/or limited otherwise.

In the description of the present invention, it should also be understood that "over" or "under" a first feature may include the first and second features being in direct contact, and may also include the first and second features being in contact not directly but through another feature therebetween, unless expressly stated or limited otherwise. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Example 1

This example discloses a ceramic filter tube, and all and/or some of the preferred embodiments of the other examples can be supplemented by this example without conflict or contradiction.

Fig. 1 and 2 show a preferred embodiment of a ceramic filter tube according to the present invention, which may include a tube body 100 of ceramic fibers for filtration. The two-way air communication between the inside of the tube 100 and the outside of the tube 100 can be realized through a plurality of air holes on the tube wall 130 of the tube 100. Preferably, the bi-directional air communication between the inside of the tube 100 and the outside of the tube 100 is achieved through a plurality of air holes on the wall 130 of the tube 100.

The tube 100 may have a hollow cavity 110 and the tube 100 is provided with an open end 120 communicating with the hollow cavity 110 only at an upper end. In the filtering state, the filtered air flows in through the tube wall 130 and out through the open end 120. In the backwash mode, the backwash air flows in through the open end 120 and out through the tube wall 130. Specifically, in the filtering state, the filtering air flows into the tube wall 130 from the plurality of air holes and flows out from the open end 120; in the backwash mode, the backwash air flows in from the open end 120 and out from the plurality of air holes in the tube wall 130.

The ceramic filter tube according to the present invention may further include a rotation shaft 200 at least partially disposed within the hollow cavity 110. The spindle 200 may be driven by a backwash air flow during backwash.

The ceramic filter tube may further include turbulator blades 300 at least partially disposed within the hollow cavity 110 for turbulating the backwash gas stream entering the hollow cavity 110 such that dust cake attached to the exterior of the tube wall 130 is exfoliated by the disturbed backwash gas stream. After turbulent flow, the dust cake attached to the outside of the tube wall 130 is more thoroughly peeled off by the turbulent air flow.

Preferably, for the present invention, the filtration state is a state in which the exhaust gas to be treated, or the filtration air flow, flows in from a plurality of air holes on the tube wall 130 of the ceramic filter tube of the present invention and flows out from the open end 120.

Preferably, the backwashing state is a state in which the backwashing gas flows in from the open end 120 and flows out from the plurality of air holes on the tube wall 130 of the ceramic filter tube. Preferably, the backwashing air flow can be pulse air flow which is matched with the turbulence blades, so that the backwashing effect is better. In some cases, backwashing is also referred to as reverse cleaning.

According to a preferred embodiment, the rotation shaft 200 is installed on the tube body 100 through the insertion part 410 inserted into the tube body 100 from the open end 120 and tightly fitted with the inner wall of the tube body 100, and after the insertion part 410 is installed on the tube body 100, gas can flow between the hollow cavity 110 and the outside of the tube body 100 through the through hole of the insertion part 410, and the insertion part 410 is pivotally connected to the rotation shaft 200 through a bearing. For example, the insertion part 410 is provided with a through hole for communicating the hollow cavity 110 with the outside. Gas can flow between the hollow cavity 110 and the outside of the tube body 100 through the through-holes of the socket 410. Preferably, the shaft 200 can be mounted on the tube 100 by being at least partially inserted into the tube 100 from the open end 120 and by the insertion part 410 being tightly fitted to the inner wall of the tube 100. The upper portion of the shaft 200 may be pivotally connected to the socket 410 by at least one first bearing 510. The rotating shaft 200 is further provided with at least one supporting portion 420 pivotally connected thereto, when the supporting portion 420 is installed in place, an outer wall of the supporting portion 420 abuts against an inner wall of the tube 100 to keep the rotating shaft 200 stable, and the supporting portion 420 and the rotating shaft 200 are pivotally connected through at least one second bearing 520. Preferably, the outer wall of the support part 420 can abut against the inner wall of the pipe body 100 in a point contact manner by means of several protrusions to maintain the stability of the rotation shaft 200. The supporting portion 420 is pivotally connected to the rotating shaft 200 by at least one second bearing 520. The outer wall of the support part 420 abuts against the inner wall of the pipe body 100 in a point contact manner through the plurality of protrusions, so that not only the stability of the rotating shaft 200 can be maintained, but also the backwash air flow can purge the outer wall of the position of the support part 420 through the gaps between the protrusions.

According to a preferred embodiment, the shaft 200 is mounted to the tube 100 by means of a spigot 410 inserted at least partially into the tube 100 from the open end 120 and fitting closely against the inner wall of the tube 100. In the case where a portion of the socket 410 is not inserted into the tube 100, the portion of the socket 410 that is not inserted into the tube 100 abuts the upper end of the tube 100 to fix and/or stabilize the socket 410. Preferably, the support part 420 may be provided at a lower end and/or between an upper end and a lower end of the rotation shaft 200. When the supporting portion 420 is disposed between the upper end and the lower end of the rotational shaft, the spoiler 300 may be divided, and each part of the spoiler is separately disposed on an independent sleeve and then sleeved on the rotational shaft 200, thereby installing the supporting portion 420 between the two parts of the spoiler.

According to a preferred embodiment, a ceramic filter tube may include a tube body 100 of ceramic fiber for filtering, the tube body 100 having a hollow cavity 110 and an open end 120 communicating with the hollow cavity 110, and bi-directional air communication between the inside of the tube body 100 and the outside of the tube body 100 is achieved through a plurality of air holes on a tube wall 130 of the tube body 100. The ceramic filter tube may further include a rotating shaft 200 at least partially disposed within the hollow cavity 110, the rotating shaft 200 being driven by the backwash air flow only during backwash; and a spoiler blade 300 at least partially disposed within the hollow cavity 110 of the tube body 100 for disturbing a backwash air flow entering the hollow cavity 110 to peel off dust cake attached to the outside of the tube wall 130 under the disturbance, the spoiler blade 300 rotating integrally with the rotation shaft 200, and the spoiler blade 300 not contacting the inner wall of the tube body 100 when rotating. Preferably, the ceramic fiber may have a diameter of 1 to 4 μm. Particularly preferably, the ceramic fiber may have a diameter of 2 to 3 μm. Thereby greatly improving the efficiency of filtering dust. Preferably, the base material of the pipe body is composed of ceramic fibers and an inorganic binder, and is formed with a mold at high temperature and high pressure.

According to a preferred embodiment, the tubular body 100 is externally coated with a gas-permeable first catalytic layer with a denitration catalyst. For example, the denitration catalyst may include CuO and Sb₂O₃. CuO and Sb in the catalyst layer when high-temperature flue gas containing NOx flows through the ceramic filter tube₂O₃As a catalyst, to promote the reaction of NOx with ammonia injected upstream of the high temperature flue gas filtration, to produce nitrogen and water vapor, one reference reaction equation is: 4NO +4NH₃+O₂→4N₂+6H₂And O. Preferably, the spoiler blade 300 may be coated with a second catalytic layer with a denitration catalyst. When the spoiler blade 300 is coated with the second catalytic layer, the unreacted NOx in the filtering airflow entering the hollow cavity from the outside of the pipe body 100 may continue to be catalytically reacted, especially the filtering airflow entering from the middle lower portion may continuously contact with the upper portions of the spoiler blade 300 at different heights in the process of flowing to the open end 120, so as to greatly increase the probability of being catalyzed and further increase the denitration effect.

According to a preferred embodiment, the porosity and pore size of the tubular body 100 gradually increase from the open end 120 to the bottom. Preferably, the porosity of the pipe body 100 may be 29 to 91%. The pore diameter of the air hole can be 2-45 μm. Particularly preferably, the porosity is 86% to 89%. The pore diameter of the pores can be 8-39 μm. Thereby, a backwash air flow of sufficient flow and velocity is provided to the area near the bottom so that the dust cake collected at the bottom can be cleaned well.

According to a preferred embodiment, the outer wall of the tubular body 100 between the bottom and the open end 120 is tapered and arranged in such a manner that the diameter of the outer wall gradually increases from the bottom of the tubular body 100 to the open end 120. Preferably, the taper is 1: 1000-1: 50. particularly preferably, the taper is 1: 100. by this way, the invention has at least the following beneficial effects: when the pipe body is manufactured through a mould, the mould is convenient to draw, and the taper is 1: 1000-1: 50 hours, can not influence the dust and attach and form the dirt cake on the outer wall, in addition, also more be favorable to peeling off of dirt cake during backwashing for backwashing efficiency is higher and clear away the dirt cake on the outer wall more thoroughly.

According to a preferred embodiment, the spindle 200 is arranged in such a way that the spindle 200 can only be driven in rotation by the backwash air flow, whereas the spindle 200 cannot be driven in rotation by the filtered air flow. If the rotating shaft 200 can be driven by the filtered air flow, a disturbed air flow is formed in the interior of the tube 100 by the filtered air flow, and it is also possible that a part of the disturbed air flow has a tendency to flow from the air holes to the outside of the tube wall, thereby affecting the adhesion of dust on the outer wall of the tube 100 to a certain extent and reducing the efficiency of the present invention in the dust removing process. Therefore, the rotating shaft 200 is set to be capable of only driving the rotating shaft 200 to rotate by the reverse washing airflow, and the filtering airflow cannot drive the rotating shaft 200 to rotate, so that the influence of the turbulence blades on the dust removing efficiency can be reduced, and dust can be attached to the outer wall to form a dust cake.

Preferably, the rotation shaft 200 is disposed in such a manner that it can be driven only by the backwash air flow and the filter air flow cannot drive the rotation shaft 200 to rotate, and may be implemented by at least one of the first bearing 510 and the second bearing 520 being a one-way bearing. At least one-way bearing is configured to: the rotation shaft is only allowed to rotate in the first rotational direction. The arrangement and mounting of the one-way bearing is well known to the person skilled in the art and will not be described further here.

Preferably, the arrangement of the spindle 200 in such a manner that the spindle 200 can only be driven by the backwash air flow and the filter air flow cannot drive the spindle 200 to rotate may be achieved by a damping element providing rotational damping to the spindle 200, and the damping element is configured to: no rotational damping is provided in the first rotational direction, which is the direction in which the backwash air flow drives the rotation of the shaft 200, and rotational damping is provided in the opposite direction of the first rotational direction, which is set to a magnitude such that the filtered air flow cannot push the shaft 200.

Preferably, the rotation of the shaft 200 can be achieved by a ratchet mechanism in such a way that the shaft 200 can only be driven by the backwash air flow and the filtering air flow cannot drive the rotation of the shaft 200. The ratchet mechanism is configured to: the rotation shaft is only allowed to rotate in the first rotational direction.

According to a preferred embodiment, the spindle 200 can be arranged in such a way that it can be driven only by the backwash air stream, whereas the filtration air stream cannot drive the spindle 200 in rotation, by one of the following: by providing at least one of the first bearing 510 and the second bearing 520 as a one-way bearing, and the at least one-way bearing is provided to allow only the rotation shaft to rotate in the first rotation direction; at least one damping element providing rotational damping by providing the rotatable shaft 200, and the at least one damping element is arranged to: providing no rotational damping in the first rotational direction and providing rotational damping in the opposite direction to the first rotational direction, the magnitude of the rotational damping being set such that the filtered air flow cannot push the rotating shaft 200; and by providing at least one ratchet mechanism arranged to only allow rotation of the shaft in the first rotational direction. Wherein the first rotating direction is the direction in which the reverse washing air flow drives the rotating shaft (200) to rotate.

Preferably, the pipe body 100 may include a pipe wall 130 and a mounting flange 140. A mounting flange 140 is provided about the periphery of the end of tube wall 130 proximate open end 120 for mounting and/or positioning of the ceramic filter tube. Preferably, the mounting flange 140 is provided at its outer edge with mounting threads, the screwing direction of which is set according to the force exerted by the filtered air flow on the rotary shaft 200 in the filtered state, with a tendency to screw the ceramic filter tube. The pivot 200 can free rotation when backwashing, and the pivot is fixed during the filtration, and corresponding turning moment can all be transmitted for ceramic filter tube, consequently, the whole turning moment that receives of ceramic filter tube is not big when filtering the air current when backwashing, and the turning to of mounting thread has the trend of screwing ceramic filter tube to set up the not hard up probability of ceramic filter tube in the later stage according to the effort that filters the air current and applys to pivot 200 under the filtration state, reduces maintenance work and cost.

Preferably, at least one of the first bearing 510 and the second bearing 520 is a one-way bearing, and the one-way bearing is disposed in such a manner that the backwash air flow can drive the rotation of the rotation shaft 200 and the filtering air flow cannot drive the rotation of the rotation shaft 200.

According to a preferred embodiment, referring to fig. 3, the shaft 200 may be a hollow shaft and the upper end of the shaft 200 extends beyond the open end 120. At least one first ventilation hole 610 is formed above the middle of the rotation shaft 200 only at a portion of the rotation shaft 200 extending beyond the open end 120. A plurality of second ventilation holes 620 are arranged in the middle and below the rotating shaft 200 so as to direct partial reverse washing air flow to flow out from the plurality of second ventilation holes 620 through the hollow part of the rotating shaft 200 from the outside of the opening end 120 during reverse washing. Thereby providing more backwash air flow to the portion of the tube remote from the open end 120, resulting in more complete removal of these portions.

Preferably, the plurality of second ventilation holes 620 are arranged at intervals between the middle and the lower end of the rotating shaft and the connecting line of the center points of the second ventilation holes 620 is located on a straight line. Therefore, the external dust cake can be flushed by a row of airflow in the rotating process of the rotating shaft, so that the dust cake is easier to peel off. Preferably, the plurality of second venting holes 620 are arranged in a manner such that the diameter is smaller as it gets closer to the open end 120. Preferably, the plurality of second ventilation holes 620 are arranged in such a manner that the opening of the through hole of the second ventilation hole 620 closer to the open end 120 is smaller.

According to a preferred embodiment, the shaft 200 is driven by the force exerted by the backwash air flow on the spoiler blades and/or by the force exerted by the backwash air flow on the driving blades 700 independently from the spoiler blades.

Preferably, the driving blade 700 is disposed at the upper end of the rotation shaft 200 extending beyond the open end 120. Therefore, before the backwash airflow enters the opening end 120, the airflow is disturbed by the driving blade 700, so that the stripping effect of the dust cake in the area adjacent to the opening end 120 is enhanced, the dust cake below is driven to be continuously stripped, and the stripping efficiency of the dust cake is improved.

Preferably, in case that the rotation shaft 200 is driven by a force exerted on the spoiler blade by the backwash air or the rotation shaft 200 is driven by a force exerted on the spoiler blade by the backwash air and a force exerted on the driving blade 700 independent from the spoiler blade 300 by the backwash air, the spoiler blade 300 has an angle with the plumb plane at least in a partial position so that the backwash air can push the rotation shaft 200 through the spoiler blade 300. For example, referring to fig. 3, the spoiler blade 300 is an integral helical blade, a plurality of split helical blades, or a plurality of flat blades arranged at an included angle with respect to the plane of the axis of the rotating shaft. For another example, referring to fig. 4, the spoiler blade 300 does not form an included angle with the plane of the axis of the rotating shaft, and the spoiler blade does not push the rotating shaft 200 under the reverse washing airflow. The spoiler blade 300 may be driven by a separate driving blade.

Preferably, the spoiler blade 300 may rotate integrally with the rotational shaft 200. Preferably, the spoiler blade 300 being at least partially disposed within the hollow cavity 110 may mean that the spoiler blade 300 is entirely disposed within the hollow cavity 110 and/or that a portion of the spoiler blade 300 is located within the hollow cavity and another portion is located outside the hollow cavity 110. Preferably, the spoiler blades 300 are disposed in such a manner that the closer to the bottom of the tube body 100, the greater the degree of disturbance of the air flow. For example, referring to fig. 5, when the spoiler blade 300 is a flat plate-shaped blade, the width of the spoiler blade 300 is larger toward the bottom of the tube body 100. For another example, when the spoiler blade 300 is a helical blade, the outer diameter of the helical body of the spoiler blade 300 is larger closer to the bottom of the tube body 100.

According to a preferred embodiment, the ceramic filter tube of the present invention may be used in a dust removing apparatus for high temperature exhaust gas. In general, a dust removing chamber is provided in a dust removing device, the dust removing chamber is divided into at least two parts by a partition plate, and a ceramic filter tube is mounted on the partition plate. For example, the partition may be provided with a plurality of mounting holes, and the corresponding ceramic filter tubes may be inserted into the corresponding mounting holes and positioned by the mounting flanges 140. The mounting flange 140 is in a baffle seal connection so that gas flow from one section of the dedusting chamber to the other section requires passage through the walls of the ceramic filter tubes to achieve filtration.

According to a preferred embodiment, the invention can be used in a high-temperature exhaust gas treatment plant, which is a high-temperature exhaust gas treatment plantSO2, NOx, HCl, HF and dust can be simultaneously removed by utilizing a combined process of SCR, dry desulfurization and ceramic filter tube filtration in one filter unit, SO that desulfurization, denitrification and dust removal can be carried out in one step under the high-temperature working condition. Has the advantages that: the desulfurization, denitration and dust removal equipment is integrated in a centralized manner, and the occupied area is small; the denitration catalyst is desulfurized in advance before denitration reaction, so that the catalyst is protected, and the service life of the catalyst is prolonged; the ceramic filter tube filters, the dust removal effect is superior to that of the traditional dust removal mode, and the stricter environmental protection standard can be met; no secondary pollution treatment of waste water is generated, and the method has more advantages in environmental protection and cost; when the ceramic filter tube integrated equipment reacts, the temperature is only reduced by 10-20 ℃, which is beneficial to the comprehensive utilization of the flue gas. Preferably, the ceramic filter tube may be a cylindrical membrane tube. The base material is ceramic fiber, and the ceramic fiber is made by a mold at high temperature and high pressure. After the SCR denitration catalyst is fused, the ceramic filter pipe has the denitration function and contains NOx and NH₃When the gas passes through the fine filter layer, the gas directly collides with the surface of the catalyst, and the reaction efficiency is very high. A contaminant removal object: dust + acid gas + nitrogen oxide; the pollutant removal effect is as follows: the dust is less than 5mg/m3, the removal rate of hydrogen chloride is as high as 97%, the removal rate of sulfur oxide is as high as 95%, and the removal rate of nitrogen oxide is as high as 95%. The optimal operation temperature is 250-450 ℃, but the ceramic filter tube can resist the temperature to 900 ℃. The characteristics of the ceramic filter tube may be: the high porosity, low density of 0.4 g/cubic centimeter, thermal shock resistance, no cracking due to thermal expansion and cold contraction, and high removal efficiency are obtained from extremely fine ceramic fiber with diameter of about 2-3 μm, which is difficult to react with chemical substances, and has high temperature resistance and similar filtering mode to that of a filter bag except for the rigid characteristic. Monomer structure: the tube body is self-supporting without a frame. Preferably, the filtering mechanism of the ceramic filter tube may be: the ceramic filter tube can form dust cakes on the surface of the filter tube in the using process, when reverse pulse cleaning operation is carried out, the dust cakes attached to the surface can be peeled off, but dust which penetrates to the depth of 1 mm of the ceramic filter tube cannot be removed, so that the dust can be prevented from further penetrating into the ceramic filter tube, and meanwhile, the filtering efficiency is improved. Ceramic filter tube is dissimilarGenerally, the conventional filter cloth has elasticity, so that dust cannot penetrate through a filter layer because the dust is completely removed by expansion during cleaning. High filtering efficiency and can treat dust with different particle sizes. The service life is longer than that of a common filter bag. Preferably, the flue gas discharged from the flue outlet is first passed through a deacidification device, such as a slaked lime or alkali reactor, and SO in the flue gas₂、SO₃HCl, HF react with slaked lime/alkali liquor to generate dust particles, then ammonia water/urea is added into flue gas after passing through a denitration device, the flue gas enters a ceramic filter pipe, NOx, the dust particles and flue gas dust are removed simultaneously in the ceramic filter pipe, the dust particles and the flue gas dust are blocked on the outer surface of the ceramic filter pipe, the dust particles and the flue gas dust fall into an ash discharge port below the ceramic filter pipe through compressed air periodic back flushing, NOx and NH3 gas react under the action of a catalyst in the ceramic filter pipe to generate nitrogen and water vapor, and the nitrogen and the water vapor are discharged into a chimney along with purified flue gas. When the flue gas passes through the fine filter layer of the ceramic filter tube, the flue gas is more contacted with the surface of the catalyst, and NOx and NH are generated₃The reaction efficiency of the gas can be higher, so that the denitration efficiency can be guaranteed, and the NH content can be greatly reduced₃The escape rate of (2).

Example 2

This embodiment may be a further improvement and/or a supplement to embodiment 1, and repeated contents are not described again. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

According to a preferred embodiment, the ceramic filter tube of the present embodiment may include a tube body 100 having a hollow cavity 110 with an inner diameter fluctuating from top to bottom, wherein the fluctuation is caused by a change in the inner diameter of the tube body 100 itself, and/or the fluctuation is caused by a rotation shaft 200 inserted into the interior of the tube body 100 through an open end 120 communicating with the hollow cavity 110. Through the fluctuation change of the inner diameter of the pipe body 100, the turbulent flow effect of the invention is better, and the difference and the change of the flowing direction of the internal airflow and the speed of the airflow flowing out from different air outlets are more obvious during backwashing, so that the dust cake is more thoroughly removed. Preferably, the inner diameter of the tubular body 100 itself may be varied by providing the tubular body 100 with threads. Alternatively, the tube 100 may comprise two portions, wherein the first tube is a smooth inner wall without threads, and the second tube is inserted into the first tube from the open end 100 to be coupled to the first tube. Therefore, only one second pipe body with fluctuating inner diameter can be designed to be inserted into the first pipe body to realize the pipe body 100 with fluctuating inner diameter from top to bottom, and the change of the original structure is reduced. Since the tube 100 is a high temperature air flow during filtering and a cold air flow during backwashing, the tube 100 is manufactured by using a mold. Therefore, during manufacturing, the amplitude of fluctuation of the inner diameter of the pipe body should be comprehensively considered, and the amplitude of fluctuation and the specific structure can be adjusted by combining experiments, so that the problems of breakage and difficult demoulding caused by uneven stress of the pipe body with fluctuation under the condition of temperature great change are prevented.

Preferably, when the ceramic filter tube is in the filtering state, the filtering air flow flows in from the radially outer side of the tube body 100 and flows out from the axially upper opening end 120. When the ceramic filter tube is in a backwashing state, the backwashing gas flows out from the axially upward opening end 120 through the fluctuating flow passage between the tube wall 130 of the tube body 100 and the rotating shaft 200. The body of the rotating shaft 200 inserted from the open end 120 in the ceramic filter pipe can be a rigid shaft or a flexible shaft. When the rotating shaft 200 serving as the flexible shaft is driven by the backwash air flow during backwash, the rotating shaft itself can obtain axial and radial bidirectional kinetic energy from an external driving mechanism, so as to prevent the condition that the backwash air flow cannot drive the rotating shaft to rotate due to excessive energy consumption in the flexible shaft.

Preferably, on the rotating shaft 200, which is a flexible shaft, at least one spoiler blade 300, which is also flexible, for disturbing the airflow may be provided. The spoiler blade 300 does not affect the flow of the filtering fluid occurring through the openings of the spoiler blade 300 in the radial direction while making a flexible contact with the inside of the pipe body 100 when rotating. When in flexible contact, the spoiler blade 200 blocks a part of air holes of the inner wall in contact with the spoiler blade at one moment of contact, and the part of air holes are communicated after being separated from the inner wall where the part of air holes are located, and at this time, the amplitude of the air velocity flowing from the part of air holes to the outer wall is changed greatly, so that the dust cake stripping effect is better.

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of the present disclosure, may devise various arrangements that are within the scope of the present disclosure and that fall within the scope of the invention. It should be understood by those skilled in the art that the present specification and figures are illustrative only and are not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims

1. A ceramic filter tube, comprising a tube body (100) of ceramic fibers for filtering, wherein the inside of the tube body (100) and the outside of the tube body (100) realize bidirectional air communication through a plurality of air holes on the tube wall (130) of the tube body (100), characterized in that,

the tube body (100) is provided with a hollow cavity (110), and only one end of the tube body (100) is provided with an opening end (120) communicated with the hollow cavity (110);

the ceramic filter tube also comprises a rotating shaft (200) at least partially arranged in the hollow cavity (110), and the rotating shaft (200) is driven by reverse washing air flow during reverse washing; and

the turbulence blades (300) are at least partially arranged in the hollow cavity (110) and used for disturbing the reverse washing airflow entering the hollow cavity (110) so as to make dust cakes attached to the outside of the pipe wall (130) peel off under the condition of the disturbed reverse washing airflow, and the turbulence blades (300) and the rotating shaft (200) rotate integrally;

wherein, in a filtering state, a filtering gas flow flows in from the tube wall (130) and out from the open end (120);

in a backwashing state, backwashing gas flows in from the open end (120) and flows out from the pipe wall (130);

the pipe body (100) is coated with a first air-permeable catalyst layer with a denitration catalyst;

a second catalytic layer with a denitration catalyst is coated on the turbulence blades (300);

the rotating shaft (200) is a hollow shaft, the upper end of the rotating shaft (200) extends out of the opening end (120), at least one first vent hole (610) is formed in the position, above the middle part of the rotating shaft (200), of the rotating shaft (200) extending out of the opening end (120), and a plurality of second vent holes (620) are formed in the middle part and below the rotating shaft (200) so that part of backwash airflow is directly drained out of the opening end (120) to flow out of the second vent holes (620) through the hollow part of the rotating shaft (200) during backwash;

the outer wall between the bottom of the tube body (100) and the open end (120) has a taper and is arranged in a mode that the diameter of the outer wall is gradually increased from the bottom of the tube body (100) to the open end (120);

the body of a rotating shaft (200) inserted from the opening end (120) and arranged in the ceramic filter pipe is a flexible shaft, and at least one flexible flow disturbing blade (300) used for disturbing airflow is arranged on the rotating shaft (200) serving as the flexible shaft.

2. Ceramic filter tube according to claim 1, wherein the turbulator blades (300) do not contact the inner wall of the tube body (100) when rotating.

3. The ceramic filter tube of claim 2, wherein the rotation shaft (200) is installed on the tube body (100) by being at least partially inserted into the tube body (100) from the open end (120) and by an insertion part (410) tightly fitted to an inner wall of the tube body (100), and the insertion part (410) is provided with a through hole for communicating the hollow cavity (110) with the outside,

the upper portion of the rotating shaft (200) is pivotally connected to the inserting part (410) through a first bearing (510), at least one supporting part (420) pivotally connected to the rotating shaft (200) is further arranged on the rotating shaft (200), when the supporting part (420) is installed in place, the outer wall of the supporting part (420) can abut against the inner wall of the pipe body (100) in a point contact mode through a plurality of protruding parts to keep the rotating shaft (200) stable, and the supporting part (420) is pivotally connected to the rotating shaft (200) through at least one second bearing (520).

4. A ceramic filter tube according to claim 3, wherein the shaft (200) is arranged to be driven only by the backwash air stream and the filter air stream is not arranged to drive the shaft (200) in rotation.

5. A ceramic filter tube according to claim 4, wherein the spindle (200) is arranged to be driven only by the backwash air stream and the filtration air stream is not arranged to drive the spindle (200) to rotate by one of:

by providing at least one of the first bearing (510) and the second bearing (520) as a one-way bearing, and at least one-way bearing is provided to allow rotation of the rotating shaft (200) only in a first rotational direction;

providing at least one damping element capable of providing rotational damping of the shaft (200) and arranged to: providing no rotational damping in a first rotational direction and rotational damping in a direction opposite to the first rotational direction, the rotational damping being sized such that the filtered air flow is unable to propel the rotatable shaft (200); and

by providing at least one ratchet mechanism arranged to only allow rotation of the shaft in a first rotational direction;

wherein the first rotation direction is a direction in which the reverse washing air flow drives the rotation shaft (200) to rotate.

6. The ceramic filter tube according to claim 5, wherein the plurality of second venting holes (620) are arranged at intervals between the middle portion and the lower end of the rotation shaft (200) and the connecting line of the center points of the respective second venting holes (620) is located on a straight line, and wherein the plurality of second venting holes (620) are arranged in such a manner that the opening of the second venting holes (620) closer to the open end (120) is smaller.

7. Ceramic filter tube according to claim 6, wherein the rotational axis (200) is driven by the force exerted by the backwash gas flow on the spoiler blade (300) and/or by the force exerted by the backwash gas flow on the driving blade (700) independent from the spoiler blade (300).