Electrostatic precipitator cleaning

Abstract

The present invention provides a wet electrostatic precipitator including an auxiliary component cleaning device. The cleaning device includes: a cleaning assembly movably supported within the electrostatic precipitator; the cleaning assembly including a scraper; the scraper being structurally designed adjacent to an auxiliary component of the electrostatic precipitator such that movement of the cleaning assembly within the electrostatic precipitator causes movement of the scraper relative to the auxiliary component, wherein the auxiliary component includes a component of a separation assembly disposed within the wet electrostatic precipitator to maintain electrical isolation between the discharge electrode and the collection electrode. The present invention also provides a method for cleaning an auxiliary component of a wet electrostatic precipitator. It is recognized that by cleaning grounded or electrically neutral auxiliary components (i.e., components other than the discharge and collection electrodes), it is helpful to maintain the overall effective operation of some electrostatic precipitator devices. These auxiliary components are generally not subject to impact, blowing, or washing due to their proximity to high-voltage components or other basic primary components of the electrostatic precipitator. The configuration provides a mechanism to maintain a minimum separation distance between the auxiliary components and the components under voltage by effectively removing clumps. Therefore, under practical operating conditions, effective clump removal can reduce the total footprint of an electrostatic precipitator device.

Description

[Technical Field]

[0001] The field of the present invention relates to a wet electrostatic precipitator including an auxiliary component cleaning device, and a method for cleaning a wet electrostatic precipitator. [Previous Technology]

[0002] Electrostatic precipitators collect dust and particulate contaminants from gases, such as air or waste gas generated as part of an industrial process. Electrostatic precipitators collect contaminants by using electrostatic force. For example, an electrostatic precipitator may be structurally designed to generate electrons through corona discharge. The generated electrons ionize the surrounding air or other gas molecules. The ionized gas molecules within the electrostatic precipitator combine with particulate matter carried in the air or waste gas. Thus, the particles become charged and are attracted by electrostatic force to a properly grounded collecting electrode.

[0003] An electrostatic precipitator device may include one or more electrically grounded collecting electrodes and one or more discharging electrodes to which a high voltage is applied. When a high voltage is applied to the discharging electrode, a corona discharge is formed between the discharging electrode and the collecting electrode. Both the collecting electrode and the discharging electrode are normally conductive.

[0004] The effective operation of an electrostatic precipitator device can depend on the nature of the corona discharge between the discharge electrode and the collecting electrode. For example, increasing the distance between the discharge electrode and the collecting electrode will lead to a decrease in efficiency and require a larger voltage to be applied to the discharge electrode to restore proper efficiency. Similarly, decreasing the distance between the discharge electrode and the collecting electrode improves efficiency, but at a reduced distance, electrical collapse is more likely to occur, which can render the electrostatic precipitator inoperable.

[0005] Particle accumulation within an electrostatic precipitator can have a detrimental effect on the effective operation of the electrostatic precipitator device. Particle accumulation can cause short circuits and / or form a corona discharge in a manner that does not support the overall effective operation of the electrostatic precipitator device. Wet electrostatic precipitator devices use a fluid (e.g., water) to clean one or more of the main components of the precipitator device.

[0006] The present invention and embodiments provide a mechanism to improve particle accumulation and improve the efficient operation of a wet electrostatic precipitator device. [Summary of the Invention]

[0007] One embodiment provides a wet electrostatic precipitator, which includes an auxiliary component cleaning device. The cleaning device includes: a cleaning assembly movably supported within the wet electrostatic precipitator; the cleaning assembly includes a scraper; the scraper may be structurally designed to be adjacent to an auxiliary component of the wet electrostatic precipitator, such that movement of the cleaning assembly within the wet electrostatic precipitator causes movement of the scraper relative to the auxiliary component, and wherein the auxiliary component includes a component of a separation assembly disposed within the wet electrostatic precipitator to maintain electrical isolation between the discharge electrode and the collection electrode.

[0008] Therefore, in addition to the primary particle removal and cleaning mechanism provided for the main components of a wet electrostatic precipitator, a secondary or supplementary cleaning configuration can be provided to help remove one or more auxiliary components of the wet electrostatic precipitator. Thus, by removing components other than the primary electrode, the accumulation of general particles or agglomerates can be reduced, and the effective operation of the primary components of the electrostatic precipitator can be maintained for a longer period than could be expected without auxiliary component removal. In some configurations, the auxiliary components removed by the cleaning device include a component positioned adjacent to a primary electrostatic precipitator component. Therefore, particles or agglomerates accumulated on this component, if not removed, may come into contact with the primary component and have a detrimental effect on its operation. Such a device can be provided as a supplementary cleaning device and is not structurally designed to remove primary electrostatic precipitator components, such as a precipitator discharge electrode or collection electrode.

[0009] According to some embodiments, the auxiliary components may include a component of a separation assembly disposed within an electrostatic precipitator to maintain electrical isolation between the discharge electrode and the collecting electrode. Therefore, mitigating the accumulation of particles or agglomerates on the auxiliary components provided and positioned to maintain the separation of the discharge and collecting electrodes can help prevent unwanted contact between these electrodes.

[0010] According to some embodiments, the movement of the cleaning assembly within the electrostatic precipitator causes a scraper to move along a surface or edge of one of the auxiliary components. The movement of the scraper along the surface or edge can help remove or eliminate particles or clumps that have accumulated on the edge or surface.

[0011] According to some embodiments, the scraper includes a narrow, elongated element. Providing a scraper with a small surface area helps prevent the accumulation of particles or clumps on the scraper itself. A scraper with a small contact area with the auxiliary component allows for more effective removal due to increased pressure at the edge or contact portion of the scraper and the auxiliary component.

[0012] According to some embodiments, the scraper includes a wire. According to some embodiments, the scraper may be electrically grounded. According to some embodiments, contact between the scraper and auxiliary components causes the scraper to be electrically grounded. Therefore, grounding of the scraper can help prevent any accumulation of particles or agglomerates on the scraper itself.

[0013] According to some embodiments, the device may be coupled to a motor configured to move the cleaning assembly relative to the auxiliary component. According to some embodiments, the device may be configured within the electrostatic precipitator such that the cleaning assembly is carried by a cleaning fluid flow to move the main body relative to the auxiliary component. According to some embodiments, the cleaning fluid includes a flow of water configured to clean the surface of at least one collecting electrode within the electrostatic precipitator device. According to some embodiments, the cleaning fluid includes a continuous or pulsed airflow configured to clean the surface of at least one collecting electrode within the electrostatic precipitator device. Therefore, the relative movement between the scraper of the cleaning device and the auxiliary component can be implemented in various active or passive manners. Implementing a device using a passive drive mechanism allows for the provision of an auxiliary component cleaning device that can be retrofitted to an existing electrostatic precipitator.

[0014] According to some embodiments, the electrostatic precipitator includes a primary component cleaning mechanism. The primary component may include a discharge or collection electrode. The cleaning mechanism may include one or more of the following: a rinsing mechanism, a tapping mechanism, or a blowing mechanism.

[0015] A further embodiment provides a method for cleaning an auxiliary component of a wet electrostatic precipitator, comprising: providing a cleaning device including a cleaning assembly including a scraper; configuring the cleaning assembly of the cleaning device to be movably supported within the wet electrostatic precipitator; and designing the scraper structure adjacent to the auxiliary component of the wet electrostatic precipitator such that movement of the cleaning assembly within the wet electrostatic precipitator causes movement of the scraper relative to the auxiliary component, wherein the auxiliary component includes an assembly of a separation assembly disposed within the wet electrostatic precipitator to maintain electrical isolation between a discharge electrode and a collection electrode.

[0016] Further specific and preferred embodiments are described in the accompanying independent and subsidiary technical solutions. Features of the subsidiary technical solutions may be appropriately combined with features of the independent technical solutions, and may be combined in combinations other than those explicitly described in the technical solutions.

[0017] Where a device feature is described as operable to provide a function, it should be understood that this includes a device feature that provides the function or is adapted or structurally designed to provide the function.

Implementation Method

[0019] Before discussing any embodiments in more detail, an overview will first be provided. The embodiments provide a configuration for supporting the efficient operation of an electrostatic precipitator device. The configuration attempts to provide a mechanism and method for reducing particle accumulation, thereby supporting the reliable generation of a corona discharge within an electrostatic precipitator.

[0020] Typically, an electrostatic precipitator operates to remove particulate matter from a gas by ionizing the particulate matter and using electrostatic force. A corona discharge is formed by providing at least one discharge electrode maintained at a high voltage and at least one collection electrode maintained electrically grounded. The resulting corona discharge forms ionized particles in a gas between the electrodes.

[0021] In an electrostatic precipitator (ESP), collecting electrodes or "grounding plates" collect particles because charged particles are attracted to them.

[0022] Next, the particles can be removed from the collecting electrode and other electrically neutral or electrically connected areas. A dry electrostatic precipitator device can remove particles by tapping (a process of physically vibrating or impacting the electrode plate to remove accumulated particles) the collecting electrode or by blowing air onto the collecting electrode. In a wet electrostatic precipitator (WESP), the collecting electrode is typically flushed with a fluid, for example, water, to prevent particle buildup. It is recognized that in some applications, particles can form solid agglomerates on components other than the primary collecting electrode, and this typical particle removal technique may be ineffective.

[0023] It should be understood that if particles accumulate excessively on a collecting electrode (or discharging electrode), the problems that accumulation can cause include: a reduction in the electrode plate separation distance, which can lead to intermittent arcing that reduces particle removal efficiency; a reduction in the electrode plate separation distance can lead to complete power shortage and subsequent loss of particle charging, making an ESP completely inoperable; a reduction in the electrode plate separation distance can lead to intermittent arcing, thus requiring the use of a higher capacity power supply; and particle accumulation on the grounding surface can lead to back corona, thus increasing the current draw of a power supply.

[0024] The described configuration recognizes that in some electrostatic precipitator devices, there may be grounded or electrically neutral auxiliary components (i.e., components other than the discharge and collection electrodes) due to the fact that these grounded components are close to the high-voltage components or other basic primary components of the electrostatic precipitator and cannot be subjected to knocking, blowing, or washing. For example, knocking or washing associated with closely spaced components can result in an unintended connection and electrical short circuit between these closely spaced components. Furthermore, the described configuration recognizes that a particular application selected for some electrostatic precipitator devices can lead to agglomeration of particles that are difficult to remove by standard knocking, blowing, and / or washing techniques. The configuration recognizes that it may be feasible to use mechanical scraping as a mechanism for cleaning the surfaces of one or more auxiliary components within an ESP. Even maintaining a cleaner surface relative to the auxiliary components of a precipitator (specifically, components located near the primary functional components) can potentially extend the time an ESP remains operational before a failure due to particle accumulation occurs.

[0025] Mechanical scraping of ESP components can be achieved in various ways. A scraper may include an element having a scraping edge or surface structured to engage with a surface of a component to be cleaned. The scraping edge may move across one or more surfaces or edges of a component to be cleaned. Movement of the scraper can occur by selecting and applying a suitable electromechanical structure, for example, by properly coupling a scraper to a motor. The movement of the scraper may occur due to one or more components or fluids associated with the standard operation of an ESP or WESP, for example, due to a cleaning fluid flow used to flush a grounded collecting electrode, or movement influenced by a blowing configuration already operated within an ESP. Electrostatic precipitator

[0026] Figure 1 illustrates an example electrostatic precipitator 10. The electrostatic precipitator 10 includes a housing 20 having an inlet (not shown) for receiving an outflow material and an outlet (not shown) for providing a processed outflow material. In this example electrostatic precipitator, the housing 20 is typically cylindrical in shape. However, it should be understood that the housing 20 can be of any suitable shape, and the inlet and outlet can be located at any suitable position.

[0027] The electrostatic precipitator 10 shown in Figure 1 includes a wet electrostatic precipitator (WESP) and includes a cylindrical inner ground plane forming a collecting electrode 30, a cylindrical outer ground plane forming a collecting electrode 40, and a discharge electrode cage 50. The discharge electrode cage 50 is maintained at a high voltage, for example, 5 to 50 kV, and in the example shown, the cylindrical inner collecting electrode 30 is cleaned.

[0028] In order to maintain the ESP structure and the separation between the components of the electrostatic precipitator 10, in the illustrated example, the discharge electrode cage 50 is mechanically coupled to the internal collecting electrode 30. The electrical isolation between the electrode cage 50 and the grounded internal collecting electrode is maintained by ensuring that the mechanical coupling or connection between the two components includes an electrically insulating element.

[0029] It should be understood that the effective operation of an electrostatic precipitator device depends on maintaining a high-voltage potential surface that is completely electrically isolated from the grounded collecting plate. In the illustrated example, the grounded inner cylindrical collecting electrode structure 30 is continuously flushed. An additional physical barrier, in the form of a separator or guard 66, is provided between the water flow used to flush the collecting electrode 30 and the insulating element forming the mechanical coupling. The barrier itself may form part of the mechanical coupling. Without this barrier or guard, the electrically insulating element forming the mechanical coupling between the discharge electrode cage 50 and the flushed collecting electrode 30 may become wet. A wet surface is no longer electrically insulating. A wet surface can provide a leakage path for the high voltage, and therefore, the ESP device may fail.

[0030] Examples of auxiliary components such as mechanical couplings, insulating elements and barriers are components within an ESP on which particulate matter can be collected and adversely affect the operation of the ESP, but such components may not be removed as part of the standard operation of the ESP.

[0031] The configuration described recognizes that, despite the existence of various mechanisms to mitigate the possibility of ESP failure, the possibility of ESP failure can be further mitigated by providing a mechanism to reduce particulate matter buildup on auxiliary ESP components (where other cleaning methods may not be suitable). By way of example, particulate matter may accumulate on the mechanical coupling between the discharge electrode and the collection electrode. For example, particulate matter may also accumulate on the separators or barriers mentioned above. The accumulation of particulate matter on one component of the mechanical coupling (for example, a separation barrier) can still cause problems with ESP operation. These auxiliary components are not easy to knock or wash with water, due to the possibility of electrical isolation affecting the main operating components of an ESP. In some cases, the distance between auxiliary components of the ESP that cannot be washed or knocked can be increased to prevent particulate matter buildup, but this comes at the cost of increasing the overall design footprint. The configuration described in more detail below provides an alternative mechanism for removing accumulated particles from the components of an ESP. Specifically, the configuration recognizes that mechanical cleaning of these components can be supported.

[0032] Mechanical cleaning can take the form of mechanically loosening, moving, or scraping particulate matter from the surface and / or edge of one or more ESP components. Mechanical cleaning can be implemented in various ways. Generally, a mechanical cleaning device can be provided, comprising at least one component configured to contact one surface or edge of an ESP component to remove an accumulation of particulate matter. The component configured to contact one surface or edge of an ESP component may include a scraper. The scraper may include a scraping edge or surface constructed to engage at least a portion of the surface or edge of the component to be cleaned. The scraping edge may be movable across one or more surfaces or edges of the component to be cleaned. For example, the scraping edge may include a scraping line. The scraping edge or element may have a small surface area such that a large number of particles or agglomerates cannot adhere to it. The scraping element itself may remain electrically grounded.

[0033] The mechanical cleaning device may be actively powered or a passive device that moves due to one or more factors associated with the standard operation of an ESP or WESP, for example, by cleaning a cleaning fluid flow or airflow that is required by rinsing or purging a grounded collecting electrode.

[0034] The operation of a WESP, components of a WESP, and a mechanical cleaning device according to one example embodiment are described in detail by way of example.

[0035] Figure 2 is an enlarged view of a portion of the wet electrostatic precipitator of Figure 1. Figure 2 shows a mechanical coupling 60 between the discharge electrode cage 50 and the internal wet collecting electrode 30. The mechanical coupling 60 is housed within the housing 20. In this embodiment, the mechanical coupling 60 is coaxially positioned within the housing 20. The mechanical coupling 60 is sized to be spaced apart from the surface of the hollow housing 20 and extends along an elongated axis of the housing 20. An electrical coupling (not shown) is coupled to the discharge electrode cage 50. The mechanical coupling 60 is electrically isolated from the housing 20. The discharge electrode cage 50 includes a plurality of shafts 70. In this example, the shafts 70 are elongated plates extending from an annular support 80 along the elongated axis of the housing 20. The shafts 70 are circumferentially positioned around the annular support 80. A plurality of axially spaced teeth 90 extend radially from each of the shafts 70. In the example shown, the teeth 90 are integrally formed with the shafts 70. Specifically, the shaft 70 and the teeth 90 are formed from a metal sheet by stamping or cutting to create a comb-like structure. Conveniently, the shaft 70 can be bent or folded to provide a surface for attachment to one of the annular supports 80.

[0036] The discharge electrode cage 50 and the internal collecting electrode 30 are connected by a mechanical coupling 60. The mechanical coupling 60 includes an elongated shaft 62 and an insulating element 64. The insulating element ensures that the discharge electrode cage 50 and the internal collecting electrode 30 are not electrically connected when mechanically connected. In the illustrated example, the insulator includes a series of axially spaced annular plate-like elements 65, which serve as an electrical insulator and electrical protector in the end regions of the substantially cylindrically concentrically arranged internal wet collecting electrode 30 and discharge electrode cage 50. The plate-like elements 65 also form a solid barrier between these ESP components. The mechanical coupling 60 includes a barrier or protector 66 in the form of an open cylinder disposed between the internal wet collecting electrode 30 and the insulating element 64. The protector 66 acts as a barrier between the fluid used to flush the wet collecting electrode 30 and the insulating element 64. In the configuration shown in Figure 2, the protective element 66 extends axially beyond the end of the collecting electrode 30 to protect the insulating element 64 from splashes of liquid used to clean the collecting electrode 30.

[0037] In the configuration shown in Figure 2, wet cleaning of the electrode 30 is performed. An internal water reservoir (not shown in Figure 2) collects water in a cavity 100 formed between an inner surface 32 of the hollow cylindrical collecting electrode 30 and an outer surface 67 of the barrier 66. A water supply device 110 supplies water to the cavity 100 via a water supply plate 120, shown in more detail in a later figure. Water from the water supply device 110 fills the cavity 100 until the water level in the cavity reaches the top lip 34 of the internal collecting electrode 30, which is in the form of a water weir lip. Water flows over the water weir lip 34 and onto an outer surface 36 of the collecting electrode 30.

[0038] In operation, as previously described, the discharge electrode cage 50 is maintained at a high potential to induce a corona discharge. The corona discharge causes ionization of particles within an ESP, which are then attracted to the outer surface of one of the grounded collection electrodes 30, 40 within the ESP. In the example shown in Figure 2, the outer surface 36 of the inner electrode is rinsed with water to remove the collected particles. Substantial continuous cleaning of the outer surface 36 can be achieved by allowing water within the cavity 100 to flow over the weir lip 34 and then along the outer surface 36, washing away the collected particles. The presence of water on the outer surface 36 does not affect the potential difference between the discharge electrode cage 50 and the collection electrode 30.

[0039] Figure 3, as a perspective view, illustrates a water supply plate 120 as shown in electrostatic precipitators such as those in Figures 1 and 2. The water supply plate 120 is in the form of a substantially annular plate and, as shown in Figure 2, can be positioned directly below the barrier 66 of the mechanical coupling 60. The water supply plate 120 includes an opening 122 to allow water to enter from the water supply unit 110. Baffles 124 formed on the plate 120 together form one or more channels 126 through which water entering from the water supply unit is forced. Water entering the plate 120 from the water supply unit leaves the plate tangentially via an outlet 128 and enters the cavity 100. As the water is released tangentially from the outlet 128 of the water supply plate, the water in the cavity 100 has a "vortex" circulation motion.

[0040] Figures 4 and 5 are photographs showing some of the main components of a WESP as shown in Figures 1 and 2, in which particle accumulation is visible. Specifically, Figure 4 is a photograph taken from the annular support 80 of the electrode cage 50 along the axis of the ESP. The axis 70 of the electrode cage 50 can be seen extending away from the camera. A cavity 100 for housing a water reservoir is visible, formed between the collecting electrode 30 and the barrier 66. Although generally clean, the photographed WESP assembly contains a particle accumulation area A on the upper edge of the barrier 66. As explained above, the barrier 66 is not rinsed and cannot be blown or tapped to remove particles. The accumulation of particles in area A adversely affects the overall operation of the ESP.

[0041] Figure 5 is a similar photographic view of one of the internal components of a WESP as shown in Figures 1 to 3. In this example, all components show particle accumulation, including significant particle accumulation in region A at the edge of barrier 66 (also known as around the insulator).

[0042] It has been found that the accumulation of particulate matter in region A, as shown in Figures 4 and 5, can cause an ESP to exhibit back corona glow during operation. The back corona glow caused by particulate matter accumulation significantly increases the power drawn by the ESP from a power supply. For optimal overall performance of the ESP, the electrode current is matched to a power supply. If additional current flow is generated due to the formation of a back corona glow, the ESP system ultimately draws more power than strictly required to remove particulate matter from a processed fluid.

[0043] It is understood that a device may be provided that can support the removal of particulate matter from one or more grounded or neutral components within an electrostatic precipitator.

[0044] FIG6 illustrates a cleaning device 200 suitable for use in an electrostatic precipitator such as those shown in FIG1 and FIG2, according to an exemplary embodiment. Device 200 includes a cleaning assembly comprising a body 210 supporting a scraper 220. In the illustrated example, the device is sized to be positionable within a cavity 100 formed between an internal collecting electrode 30 and a barrier 66. Specifically, the body is sized to be adjacent to, but spaced apart from, the inner surface 32 of the collecting electrode 30 and the outer surface 67 of the barrier 66. The device body 210 has a curvature selected to conform to the space between the internal collecting electrode 30 and the barrier 66. This selection of size and shape allows device 200 to rotate freely within the cavity and allows the body to carry the scraper 220 along a path around the barrier 66. The main body 210 of the device extends downward into the cavity 100 and is at least partially submerged in a reservoir of cleaning fluid within the cavity 100. The main body 210 of the device may be formed of a material that prevents the device 200 from floating in water or of other cleaning fluid supplied to the cavity 100. The material chosen for the main body of the device is not too dense or the device is not too heavy to prevent movement of the fluid within the reservoir used to carry the device 200 forward.

[0045] The materials and weight of the device are carefully selected so that the device 200 does not simply float on the surface of the reservoir, and is prevented from sinking into the cavity 100 by a scraper 210 placed on the upper edge of one of the barrier walls 66. The main body of the device is kept upright by a support 230 disposed on the body so that it rests on the water weir lip 34 of the internal collecting electrode 30 during use. In other words, the main body of the device is suspended from the scraper 220 and the support 230, so that it is positioned in the cavity without touching the inner surface 32 of the collecting electrode 30 or the outer surface 67 of the barrier wall 66. Because the axial length of the barrier wall extends axially beyond the length of the collecting electrode, the scraper 220 is held in a groove provided in a scraper support 225 protruding from the upper surface of one of the device bodies 210, while the support 230 is held in a proper position by extending downward into a groove in the device body itself.

[0046] In use, the circumferential movement of the cleaning fluid within the cavity 100, induced by the plate described in FIG3, is used to carry the device 200 around in a substantially circular path. The circumferential movement of the cleaning fluid is induced by the arrangement of the water supply plate, ensuring that the cleaning fluid flows uniformly across the weir lip 34 to clean all portions of the internal collecting electrode. In the illustrated embodiment, this existing circumferential movement of the cleaning fluid is used to induce movement of the cleaning assembly relative to other components of the ESP. The body 210 includes a shaped nose region 215 to reduce frictional fluid resistance to movement of the device within the reservoir. A scraper 220 rests on the edge of the barrier and is used to remove any particles that have accumulated and adhered to the top edge of the barrier 66. Any removed particles may fall toward the insulating element 64 and are therefore unlikely to affect the operation of the discharge and collecting electrodes, or may fall into the cleaning fluid and then cross the weir lip 34. Improved barrier removal helps increase the maintenance interval of an electrostatic precipitator.

[0047] In the illustrated example, the scraper 220 is in the form of a metal rod or wire, as is the stabilizing support 230. The wire scraper has a small surface area, so that a large number of particles or clumps cannot adhere to it when it scrapes the edge of the barrier 66. The scraper wire 220 is also electrically grounded, at least through direct contact with the barrier 66.

[0048] Figure 7 illustrates an alternative cleaning device suitable for use in an electrostatic precipitator such as those shown in Figures 1 and 2, according to an exemplary embodiment. In this alternative embodiment, device 300 includes a body 310 supporting a scraper 320. In the illustrated example, the device is positioned within a barrier 66, between an inner surface of the barrier and an insulating element 64. The body 310 is in the form of an elongated portion, one end of which is connectable to the scraper 320, and the other end is connectable to a gear 330. The gear 330 is substantially annular and has a toothed inner ring surface 334 and a smooth outer ring surface 336. The toothed inner ring surface 334 is structurally designed to engage with cooperating teeth of a drive gear 340, which is connectable to a rotary drive shaft 350 extending along the axis of the precipitator through a water supply plate 120. Rotation of the drive gear 340 causes device 300 to move circumferentially about the barrier 66. By employing a scraper 320 supported by the device body 310 in the form of a line extending along and contacting the upper edge of the barrier 66, the same scraping and removal of clumps or particles that may have accumulated on the upper edge of the barrier during the use of the electrostatic precipitator, as described in the example embodiment shown in FIG6, is achieved.

[0049] Figure 8 is a photograph showing some of the main components of a WESP as shown in Figures 1 and 2, wherein a device such as that shown in Figure 6 is operable. The cleaning device 200 can be seen positioned in the cavity 100 between the internal collecting electrode 30 and the barrier 66. For example, although particle accumulation can be seen on the discharge electrode shaft 70, the annular support 80, and the insulating element plate 65, there is no significant accumulation at the barrier 66 of any kind that would cause the electrostatic precipitator to fail or operate inefficiently.

[0050] It should be understood that the described configuration provides an ESP in the form of a WESP. A WESP is used to support a short electrode spacing because water or other fluids can be used to clean at least one primary operating component of the WESP. The normal operating corona current of a WESP is low. It is set to a level sufficient to provide an electric field that causes the propagation of such particles, in addition to providing a charging mechanism for the particles.

[0051] It is recognized that, for example, providing a cleaning device in the form of a scraper facilitates the removal of particulate matter that might otherwise accumulate on a section between a water-flushing weir and an insulating surface of the WESP. It has been observed that if this particulate accumulation is not removed, back corona or arcing may occur at the operating voltage of the WESP. It is recognized that some components of a WESP (including auxiliary components) cannot be knocked to dislodge or remove particulate accumulations. This is especially true in a WESP, as the particles may be wet and therefore cannot be easily dislodged or removed in this manner. Providing a movable cleaning part that can move continuously or periodically within the WESP can help avoid particulate accumulation. While it may be intuitively thought that providing an additional device or component within the operating area of ​​a WESP would cause additional debris accumulation, it has been found that by providing a thin, linear mechanical scraper on a moving body, the scraper can remove any particulate accumulation and prevent particulate material from accumulating on itself or on the scraped auxiliary components. In other words, the cleaning device described can help mitigate, to some extent, the buildup of unwanted electrical pathways within the WESP.

[0052] According to the described configuration, an interface between an insulator of the WESP and a water flushing section is cleaned. In other words, the auxiliary component to be cleaned may include a component that is not itself an insulator and may be grounded but not flushed. This provides a mechanism to remove build-up that may occur on an auxiliary part of a WESP that cannot be flushed or struck.

[0053] It should be understood that in some of the described embodiments, the cleaning device is powered by a tangential water flow that has formed the portion of the WESP's primary operation, and any debris removed by the cleaning device can be flushed away by the tangential water flow that has formed the portion of the WESP's primary operation. Therefore, no additional collection funnel is required for the removed or cleaned particles. Furthermore, providing appropriate components on the cleaning device can facilitate the wicking of water through a weir of the WESP. In the illustrated configuration, the stabilizing support 230 operates to balance the cleaning device, thereby reducing resistance to movement of the cleaning device and helping the device slide around the circumference of the WESP, but also serving to provide a path that helps water to be wicked evenly across the weir.

[0054] Although illustrative embodiments of the invention have been disclosed in detail herein with reference to the accompanying drawings, it should be understood that the invention is not limited to the precise embodiments, and that various changes and modifications may be made therein by those skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents. [Simplified Explanation of the Diagram]

[0018] Embodiments of the present invention will now be further described with reference to the accompanying drawings, in which: FIG1 illustrates an example electrostatic precipitator; FIG2 is an enlarged view of a portion of the example electrostatic precipitator of FIG1; FIG3 is a perspective view illustrating a water supply plate 120 as shown in the electrostatic precipitator of FIG1 and FIG2; FIG4 is a photograph showing some of the main components of a precipitator as shown in FIG1 and FIG2; FIG5 is a photograph showing some of the main components of a precipitator as shown in FIG1 and FIG2; FIG6 illustrates a cleaning device suitable for use in an electrostatic precipitator as shown in FIG1 and FIG2 according to an example embodiment; FIG7 illustrates an alternative cleaning device suitable for use in an electrostatic precipitator as shown in FIG1 and FIG2 according to an example embodiment; and FIG8 is a photograph showing some of the main components of a WESP as shown in FIG1 and FIG2, wherein the device shown in FIG6 is operable.

Claims

1. A wet electrostatic precipitator, comprising an auxiliary cleaning component, the cleaning component including: A cleaning assembly is movably supported within a wet electrostatic precipitator; the assembly includes a scraper; the scraper is configured to abut an auxiliary component of the wet electrostatic precipitator such that movement of the cleaning assembly within the wet electrostatic precipitator causes movement of the scraper relative to the auxiliary component, wherein the auxiliary component includes a component of a separation assembly disposed within the wet electrostatic precipitator to maintain electrical isolation between a discharge electrode and a collecting electrode, wherein the cleaning device is disposed within the electrostatic precipitator such that the cleaning assembly is carried by a cleaning fluid flow to move the cleaning assembly relative to the auxiliary component, and wherein the cleaning fluid includes a water flow configured to clean the surface of at least one collecting electrode of the electrostatic precipitator device.

2. The wet electrostatic precipitator of claim 1, wherein movement of the cleaning assembly within the electrostatic precipitator causes the scraper to move along one of the surfaces or edges of the auxiliary components.

3. The wet electrostatic precipitator as claimed in claim 1, wherein the scraper includes a narrow, elongated element.

4. The wet electrostatic precipitator as claimed in claim 1, wherein the scraper includes a single wire.

5. The wet electrostatic precipitator as requested in item 1, wherein the scraper is electrically grounded.

6. The wet electrostatic precipitator as claimed in claim 1, wherein the contact between the scraper and the auxiliary component causes the scraper to be electrically grounded.

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