JP4704323B2 - Electric dust collector and drying control method of electric dust collector - Google Patents

Description

  The present invention relates to an electrostatic precipitator and a method for controlling drying of an electrostatic precipitator, and in particular, collects fine particles charged by corona discharge using a coulomb force with a rotating adsorption plate and fine particles. The adsorbed plate is washed away by the liquid pressure of the sprayed cleaning solution, and after the cleaning, the adsorbing plate is quickly dried, and the particles can be collected in a short time and restarted. The present invention relates to a possible electrostatic precipitator and a method for controlling drying of an electrostatic precipitator.

  Conventionally, before releasing so-called "industrial waste gas" such as soot emitted in large quantities from boiler exhaust of a factory, power plant, etc. into the atmosphere, various powders and oils contained in industrial waste gas or An air cleaning process may be performed to remove fine particles that may contaminate the atmosphere such as mist or dust containing moisture. The release of industrial waste gas containing these fine particles directly into the atmosphere has a profound impact on the global environment, so it may be obliged to collect them according to standards of national and local governments. In urban areas, air pollution caused by exhaust gas from cars is serious, and some homes are equipped with air cleaners for home use. In addition, in restaurants such as yakiniku restaurants, smoke and polluted air generated during cooking is released directly from the kitchen, etc., and the contaminated air is cleaned with an air purifier before release in order to avoid dissatisfaction with neighboring residents. There are many places where equipment is installed.

  Various principles and types of devices (dust collectors / air purifiers) for purifying the contaminated air have already been developed. In particular, it is known that an electric dust collector (electric dust collector) is superior from the viewpoint of dust collection performance, and is widely spread in many industrial fields. Here, the general collection principle of the electrostatic precipitator will be described. Contaminated air rectified so as to pass through the vicinity of the discharge electrode using corona discharge generated by applying a high voltage to the discharge electrode. A predetermined charge is given to the fine particles therein, and the charged (charged) fine particles are electrically attracted to the dust collecting electrode that is electrically opposite to the discharge electrode by using Coulomb force to be collected. The characteristics of this electric dust collector are 1) Less pressure loss than other dust collectors, 2) Capable of treating a large amount of gas at once, 3) High dust collection rate (dust collection performance), etc. Has an excellent advantage. For this reason, it treats relatively small and medium-sized contaminated air such as kitchens in order to prevent odors from touching nearby areas such as factories and power plants, especially in environments where large amounts of polluted air are discharged, and restaurants such as yakiniku restaurants. It is often used in an environment where

  The applicant of the present application collects fine particles charged by corona discharge with a rotating adsorption plate (corresponding to a dust collection electrode), and has a remarkable dust collection efficiency even after continuous operation for a long time. An electrostatic precipitator having a novel configuration that suppresses the decrease and further reduces the frequency of maintenance such as cleaning of the suction surface has been developed, and patent applications have already been filed (for example, Patent Document 1 and Patent Document 2) reference).

JP 2003-126729 A JP 2004-141826 A

  By the way, as described above, the electrostatic precipitator that rotates and collects the suction plate changes the position of the suction surface of the suction plate from time to time. Is also disjoint. Therefore, unlike the conventional electrostatic precipitator, charged fine particles are not attracted to a part of the dust collecting electrode. As a result, there was an excellent advantage that the dust collection efficiency (collection efficiency) does not decrease so much in a short time even during operation for a long time. However, the accumulation (deposition) of the fine particles collected on the adsorption plate reduces the Coulomb force between the adsorption plate and the charged plate that repels the fine particles, thereby reducing the collection efficiency of the fine particles. there were. In order to solve this problem, after a long continuous operation, it is necessary to clean the suction plate (suction surface) in order to return the dust collection efficiency to the original state.

  Here, in order to remove the fine particles from the adsorption plate, for example, a cleaning mechanism such as an automobile wiper is provided, a cleaning liquid (water or surfactant water) is sprayed on the adsorption surface, and the wiper is rotated while rotating the adsorption plate. A method of physically removing fine particles by scraping them at a portion or a method of spraying a cleaning liquid onto the adsorption surface and washing away the fine particles from the adsorption surface by the liquid pressure is employed.

  By the way, there is a possibility that the cleaning liquid sprayed on the suction surface of the suction plate is scattered by the rotating suction plate to every part of the air passage according to the centrifugal force. For this reason, in addition to the suction surface of the suction plate, for example, discharge means for charging fine particles may become wet with the cleaning liquid. In this state, even if a discharge voltage capable of generating corona discharge is supplied, the discharge means that should have been electrically insulated and the collection means such as the suction plate mediate the conductive cleaning liquid. In other words, since it is electrically connected, in other words, in a short-circuited state, corona discharge could not be generated. Therefore, after cleaning with the cleaning liquid, it is necessary to completely dry both the discharge means and the collection means by forced drying such as natural drying or hot air, and to make them insulative again. For this reason, a lot of time may be required for the operation for drying, and as a result, the time for keeping the electrostatic precipitator in a non-operating state becomes long. For this reason, there is a possibility that the operating rate may be lowered, or the collection of fine particles by the electric dust collector as a whole becomes inefficient.

  Therefore, in view of the above circumstances, the present invention reduces the time from cleaning of the adsorption plate with the cleaning liquid to re-operation, and further improves the operating rate, and drying control of the electric dust collector. It is an object to provide a method.

In order to solve the above problems, an electrostatic precipitator according to the present invention has an internal air passage that communicates an intake port that sucks contaminated air containing fine particles and an exhaust port that discharges clean air from which the fine particles have been removed. An air flow generating means for generating an air flow in the air passage, for sucking the contaminated air and exhausting the clean air, and provided in the air passage and orthogonal to the flow direction of the air flow. Adsorption shaft spanned in a passage, presenting a substantially disk shape, the fine particles mounted on the adsorption shaft with the respective adsorption surfaces facing each other and charged on the adsorption surface using Coulomb force A plurality of adsorption plates for adsorbing and collecting, and a collection means provided with adsorption plate rotating means connected to one end of the adsorption shaft and rotating the adsorption plate according to the adsorption axis; and provided in the air passage A discharge shaft that is bridged in the air passage perpendicular to the flow direction of the airflow, and is inserted between a pair of the suction plates that are supported by the discharge shaft and face each other, and the suction plate A plurality of charged plates placed in close proximity to the suction surface and electrically insulated from the suction plate, and arranged near the suction plate facing edge of the charge plate, with a sharp tip A plurality of discharge electrode portions each having a formed sharp end portion; a discharge means for charging the fine particles contained in the contaminated air by corona discharge; and electrically connected to the discharge shaft of the discharge means; Discharge voltage supply means for supplying a discharge voltage capable of generating the corona discharge from the electrode section, and provided in the air passage. A plurality of spray nozzles, and the spray nozzles connected to the spray nozzles, in order to clean the fine particles adsorbed on the suction surface with the cleaning liquid ejected from the spray nozzles, and pump the cleaning liquid into the air passage and supply The cleaning liquid is removed from the discharge means including the suction surface cleaning unit including the cleaning liquid supply unit, the collection unit including the suction plate cleaned by the suction surface cleaning unit, and the discharge electrode unit in which the cleaning liquid is scattered. And an electric dust collector including a drying control unit that dries the corona discharge in the air passage so that the corona discharge can be generated. The drying control unit controls the discharge voltage supply unit, and the corona Limited voltage supply means for supplying the discharge electrode unit with the discharge voltage capable of generating discharge limited to a preset unit time, and the limited voltage supply means Spatter removing means for rotating the suction plate on which the cleaning liquid remains when the discharge voltage is supplied to the discharge electrode unit according to the suction shaft and scattering the cleaning liquid from the suction plate using centrifugal force; the actual measurement voltage value measurement means for measuring the actual voltage value at the time of discharge voltage supply, said measured actual measurement voltage value between the supply the discharge electrode part and the suction plate is in the discharge voltage, the corona discharge Measured voltage value determining means for determining whether or not the charge of the fine particles exceeds a possible start reference voltage value, and when the measured voltage value exceeds the start reference voltage value, the discharge voltage supply means And continuously supplying the discharge voltage capable of generating the corona discharge to the discharge electrode unit, and controlling the air flow generating means, Re-starting means for starting intake and collecting the fine particles using Coulomb force; and when the measured voltage value is smaller than the starting reference voltage value, controlling the limited voltage supply means, and again discharging the discharge And a re-drying means for supplying a voltage to the discharge electrode unit by limiting the voltage to the unit time ”.

  Here, the fine particles contained in the polluted air are solid waste contained in industrial waste gas and automobile exhaust gas discharged from various facilities such as factories, oil content discharged from restaurants' kitchens, etc. A mist-like substance containing a large amount of moisture can be exemplified, and corresponds to a so-called “floating particulate matter” floating in a gas. Furthermore, the airflow generating means generates an air flow (airflow) in the air passage. For example, the propeller (blade) connected to a driving device such as a motor is rotated, and the propeller is rotated. To generate airflow. In addition, by appropriately changing the propeller diameter of the propeller to be used and the rotational speed of the motor for driving, the flow rate of the airflow flowing in the air passage, the flow speed (flow velocity), and the like can be arbitrarily changed.

  On the other hand, the collecting means is such that electric charges are given to the fine particles in the contaminated air by the discharge means described later, and the charged particles are adsorbed on the adsorption surface of the adsorption plate electrically opposite to the adsorption plate by utilizing Coulomb force. , To collect. At this time, the suction plate that constitutes the collecting means is rotated according to the suction axis by a plate rotating means (rotating motor or the like). Therefore, the positional relationship between the fine particles contained in the contaminated air flowing in the air passage and the adsorption surface changes every moment. Therefore, the fine particles collected by the Coulomb force are adsorbed without being biased toward a specific portion of the adsorption surface of the adsorption plate, and finally adhere almost uniformly over the entire adsorption surface.

  In addition, the discharge means generates corona discharge with respect to the polluted air sucked from the intake port, gives electric charges to the fine particles contained in the polluted air, and puts them into a charged state. Such a configuration mainly includes a discharge shaft and a charge plate connected to the discharge voltage supply means, and a discharge electrode portion. Here, it is known that corona discharge is generally easily generated from a pointed tip. Therefore, in this invention, the discharge electrode part provided with the some sharp end part which formed the front-end | tip sharply is used. The sharp end portion is arranged along the flow of the airflow, in other words, in a direction in which the tip is separated from the intake port. The charged plates are respectively inserted between the suction plates at a predetermined interval with respect to the width direction of the air passage. On the other hand, the discharge electrode portion is located at the height of the air passage along the opposite edge of the charge plate. A plurality are arranged in the vertical direction, the upper end is formed in a bowl shape, and is attached so as to be caught by the discharge shaft. For this reason, most of the contaminated air sucked from the intake port passes through the vicinity of the discharge electrode portion where corona discharge is generated. As a result, almost 100% of the fine particles contained in the contaminated air are charged by corona discharge. Here, the material constituting the discharge electrode portion is not particularly limited, but the sharp end portion that melts due to the high temperature during corona discharge, avoids the loss of the sharp shape that can generate corona discharge, and makes corona discharge efficient. Therefore, it is necessary to provide a function having excellent electrical conductivity in order to generate them automatically. Therefore, for example, a relatively hard material such as tungsten or a tungsten compound may be used. The discharge voltage supply means is connected to a household power supply or a commercial power supply and can supply a high voltage to the discharge electrode portion.

  Further, the suction surface cleaning unit is a means for cleaning and supplying a cleaning liquid containing water or a surfactant from an injection nozzle provided with an injection port toward the suction surface of each suction plate (for example, an air pump). It is sprayed using, and the adhered fine particles are washed away by the water pressure (hydraulic pressure) of the cleaning liquid. Therefore, a tank provided outside the housing for storing the cleaning liquid, a supply hose connected to the tank and guiding the cleaning liquid into the air passage, a branch pipe arranged to branch from the supply hose to the plurality of injection nozzles, and It has a plurality of configurations such as an injection nozzle provided at the end.

  On the other hand, the drying control unit is for quickly drying the wet suction plate after cleaning and enabling the processing for removing the fine particles from the contaminated air again. This is achieved by controlling the processing timing of each component of the duster. More specifically, the collecting principle of the electrostatic precipitator of the present invention is to collect fine particles on the adsorption surface using Coulomb force. The collecting means must be in an electrically insulated state. However, the structure including the intake plate is wetted with the cleaning liquid in the air passage after cleaning by the suction surface cleaning unit. At this time, the cleaning liquid contains a conductive component, and the collecting means such as the suction plate and the discharging means such as the discharge electrode portion are electrically short-circuited. Therefore, the drying control unit functions to restore the shorted state to the original state. The drying control unit is configured to electrically control the configuration of the above-described discharge means and the like to enable drying, and is a main control unit (control plate, control for electrically driving the electrostatic precipitator 1. Circuit, etc.), or a procedure for drying may be programmed in advance in a storage means such as a memory.

  Therefore, according to the electrostatic precipitator of the present invention, after the fine particles adsorbed on the adsorption plate are washed with the liquid pressure of the washing liquid by the adsorption surface washing unit, the electric precipitator is operated again to remove the fine particles contained in the contaminated air. This shortens the time until the collecting process is performed. More specifically, after the cleaning liquid is jetted, the discharge voltage supply means is controlled to supply the discharge voltage temporarily only for a preset unit time (for example, 0.5 s). At this time, the suction plate wet with the cleaning liquid, the discharge electrode portion, etc. cannot generate a corona discharge sufficiently due to an electrical short circuit, or a spark corresponding to an incomplete corona discharge is instantaneous. Will occur. At this time, if a current flows through the cleaning liquid forming a part of the short-circuited circuit, resistance heat is generated, and the temperature of the cleaning liquid is increased. By repeatedly supplying this discharge voltage, the temperature rises to a temperature at which the cleaning liquid can be finally evaporated and is dried. On the other hand, due to the occurrence of a spark, the cleaning liquid close to the spark may instantaneously become a high temperature and evaporate. Therefore, by repeatedly supplying a discharge voltage limited to unit time, the cleaning liquid in the air passage, in particular, between the adsorption plate and the discharge electrode or the charge plate is evaporated and dried.

  At this time, immediately after the start of supply of the discharge voltage by the limited voltage supply means, that is, when the number of times of supply of the discharge voltage is about several times from the first time, the temperature of the cleaning liquid causing the short circuit is sufficiently increased, Alternatively, it is difficult to completely evaporate, and there is a difference between the measured voltage value and a voltage sufficient to generate a complete corona discharge (starting reference voltage value). Corresponding sparks are only slightly generated. Therefore, the cleaning liquid is gradually evaporated and the inside of the air passage is dried by performing the supply for a plurality of times per unit time of the discharge voltage. On the other hand, when the start reference voltage value is exceeded, as already described, it is possible to drive the air flow generation means, start intake of contaminated air, and restart the electrostatic precipitator.

  Here, when a discharge voltage capable of generating corona discharge is continuously supplied in a state of being short-circuited by the cleaning liquid, a great load is applied to each electric device constituting the discharge voltage supply means. The safety circuit provided in the dust collector itself may detect such a short-circuit state, and the supply of the discharge voltage may be interrupted. However, in the above description, when the discharge voltage is supplied only for a preset unit time and does not reach the reference start voltage, the cleaning liquid is supplied safely and reliably by repeating the above process. It is possible to evaporate from within the passage.

  Furthermore, according to the electrostatic precipitator of the present invention, when supplying the discharge voltage intermittently, by rotating the suction plate, it becomes possible to scatter the cleaning liquid to the outside of the suction plate by centrifugal force. The washing liquid can be removed from the plate at an early stage, and drying can be performed quickly. In addition, since the location where corona discharge (or spark) is generated changes on each suction surface of the suction plate as needed, the entire suction surface can be sparked on average and can be uniformly dried. .

  Furthermore, in addition to the above configuration, the electrostatic precipitator according to the present invention may be “the start reference voltage value is set to 8000 volts or more and 12000 volts or less”.

  Therefore, according to the electrostatic precipitator of the present invention, the starting reference voltage value is set to 8000 volts or more and 12000 volts or less. Here, corona discharge is generally generated using a discharge voltage of about 10,000 volts in general. Therefore, by setting 8000 volts, which is slightly lower than the 10,000 volts, as the lower limit of the starting reference voltage value, it is possible to continuously generate corona discharge after confirming that it has sufficiently dried. Note that the lower limit of the starting reference voltage value is set to 12000 volts, because at a higher voltage than this, a great load is applied to the discharging means and the discharging voltage supply means of the electrostatic precipitator, thereby impairing the durability of the entire device. Therefore, it is not preferable. Therefore, by setting the starting reference voltage value to 8000 volts or more and 12000 volts or less, it becomes possible to execute the plan in the range of an appropriate discharge voltage.

On the other hand, the method for controlling the drying of an electrostatic precipitator according to the present invention includes a “ plate rotation control step of rotating the suction plate wet with the cleaning liquid according to the suction shaft, and controlling the discharge voltage supply means while the suction plate is rotated. And a limited voltage supply step of supplying a discharge voltage for generating corona discharge from the discharge electrode unit to a preset unit time, and the discharge electrode unit supplied with the discharge voltage and collected An actual voltage value measuring step for measuring the actual voltage value between the suction plates in a state where the fine particles are washed and wet with the cleaning liquid, and a starting reference that allows the determined actual voltage value to be charged by the corona discharge. An actual voltage value determination step for determining whether or not the voltage value is exceeded, and when the actual voltage value exceeds the start reference voltage value, the discharge voltage supply means is controlled, The discharge voltage capable of generating Rona discharge is continuously supplied to the discharge electrode unit, the air flow generation means is controlled, the intake of contaminated air from the intake port is started, and the fine particles are utilized using Coulomb force. A restarting step for collecting the discharge voltage, and when the measured voltage value is smaller than the start reference voltage value, the limited voltage supply means is controlled, and the discharge voltage is limited to the unit time again to the discharge electrode unit. And a re-drying process to be supplied to. "

  Therefore, according to the drying control method for an electrostatic precipitator of the present invention, before the electrostatic precipitator is restarted after cleaning, the discharge voltage is intermittently supplied every short unit time, and the heat generated by the flowing current is generated. The cleaning liquid can be gradually evaporated and the inside of the air passage can be dried by the spark. As a result, an insulating state between the discharge electrode portion and the suction plate is formed, and corona discharge can be stably generated.

  Therefore, according to the drying control method for an electrostatic precipitator of the present invention, the discharge voltage is supplied in a limited manner while the suction plate is rotated. Thereby, the cleaning liquid is scattered into the air passage by the centrifugal force accompanying the rotation of the suction plate, and the time required for drying can be shortened.

  According to the electrostatic precipitator of the present invention and the drying control method thereof, by collecting the collection means such as the suction plate wetted with the cleaning liquid and the discharge means such as the discharge electrode part by repeatedly supplying the discharge voltage intermittently, The cleaning liquid adhering to the suction plate or the like can be evaporated and dried in a short time, and the time required from the cleaning of the electrostatic precipitator to the re-operation can be shortened.

  Hereinafter, an electrostatic precipitator 1 according to an embodiment of the present invention and a drying control method 2 of the electrostatic precipitator will be described with reference to FIGS. 1 to 6. Here, FIG. 1 is an explanatory view seen from the side schematically showing the internal configuration of the electrostatic precipitator 1 of the present embodiment, and FIG. 2 schematically shows the internal configuration of the electrostatic precipitator 1. FIG. 3 is an explanatory diagram viewed from above, FIG. 3 is a schematic cross-sectional view taken along the line AA of FIG. 1 schematically showing the internal configuration of the electrostatic precipitator, and FIG. And FIG. 5 is a block diagram showing the functional configuration of the main control unit 37, and FIG. 6 is a diagram of the process of the drying control method 2 of the electric dust collector. It is a flowchart which shows a flow.

  As shown mainly in FIGS. 1 to 5, the electrostatic precipitator 1 of the present embodiment discharges purified air 9 that has been purified through the intake port 8 that sucks contaminated air 7 containing fine particles 6 and the electrostatic precipitator 1. A housing 12 made of a stainless steel casing having a substantially rectangular parallelepiped shape and having an air passage 11 extending in a substantially horizontal direction communicating with the exhaust port 10 and a downstream side of the air passage (corresponding to the right side in FIG. 1). In order to suck contaminated air 7 from the intake port 8 and exhaust clean air 9 from the exhaust port 10, an air flow (air flow 13) is provided in the air passage 11. An airflow generation unit 16 that is formed so as to protrude entirely from the rotating fan 14 to be generated and the outer shell of the housing 12, and includes a driving motor 15 for driving the rotating fan 14, and the width direction of the air passage 11 ( 3 substantially corresponds to the horizontal direction of the paper surface in FIG. 3 and is supported by a substantially rod-shaped suction shaft 17 that is rotatably supported in a horizontal manner, and the suction surfaces 18 are opposed to each other. A plurality of suction plates 5 having a disk shape installed so as to penetrate, and one shaft end 17a of the suction shaft 17 pivotally supported by the housing 12 are connected via a drive transmission mechanism 20 such as a gear, The air passage 11 in a state of being electrically insulated from the collection unit 22, and the collection unit 22 including a plate rotation motor 21 that generates a rotational force for cooperatively rotating all the adsorption plates 5 according to the adsorption shaft 17. The discharge surface 25 is brought close to the suction surface 18 of the suction plate 5 by a pair of discharge shafts 23 and a charge plate support shaft 24, respectively, which are stretched across the width direction of the plate and supply a discharge voltage. Is supported Discharge having a plurality of charging plates 4 having a substantially rectangular shape, and a plurality of discharge electrode portions 3 having sharp end portions 28 projecting from the air inlet 13 in the direction in which the air flow 13 flows from the inlet-facing edge 27 of the charging plate 4 A discharge voltage supply unit 31 that is electrically connected to the discharge shaft 23 of the discharge unit 30 and supplies a discharge voltage capable of generating a corona discharge CD from a sharp pointed end 28; An injection nozzle 34 that is installed above and has an injection nozzle 33 facing the suction surface 18 of the suction plate 5 that can spray the cleaning liquid 32. The supply hose is connected to the injection nozzle 34 and supplies the cleaning liquid 32 to the injection nozzle 33. 35 and a storage tank (not shown) that is provided outside the housing 12 and temporarily stores the supplied cleaning liquid 32, and supplies the stored cleaning liquid to the injection nozzle 34 using air pressure. A main controller 37 that is connected to the suction surface cleaning unit 36 having an air pump (not shown), the airflow generation unit 16, the collection unit 22, and the discharge unit 30 and that can electrically control each component. It is mainly comprised.

  Here, the main control unit 37 includes an operation control unit 26 that controls operations such as overall operation and stop of the electrostatic precipitator 1, start and stop of the suction surface cleaning unit 36, and the main configuration of the present invention. A certain drying control unit 29 is functionally constructed inside. More specifically, the drying control unit 29 can control the electrostatic precipitator 1 after the suction surface cleaning unit 36 is performed, and can perform the drying and re-operation processes, as shown in FIG. As described above, as a functional configuration, the discharge voltage is applied to the discharge electrode unit 3 only for a short time (unit time: for example, 0.5 s) set in advance on the suction plate 5 or the like wet with the cleaning liquid 32. Voltage supply means 38 for causing the discharge voltage supply unit 31 to perform the process of supplying the discharge voltage, and the measured voltage value measurement for measuring the measured voltage value between the discharge electrode unit 3 and the suction plate 5 when the discharge voltage is supplied in a limited manner Means 39, storage means 40 for storing reference voltage data 40a related to a preset start reference voltage value (for example, 8000 volts), start reference voltage value corresponding to the stored reference voltage data 40a and measured actual voltage value When The measured voltage value determining means 41 for comparing and determining the magnitude of the voltage, and if the measured voltage value exceeds the start reference voltage value as a result of the determination, controls the discharge voltage supply unit 31 to generate the corona discharge CD. The discharge voltage (for example, 10,000 volts) is continuously supplied to the discharge electrode unit 3, the air flow generation unit 16 is controlled, the intake of the contaminated air 7 is started from the intake port 8, and the coulomb force is used to generate fine particles. 6 is collected, and when the measured value is smaller than the starting reference voltage value, the limited voltage supply unit 38 is controlled, and the discharge voltage is again limited to a short unit time. It mainly comprises a re-drying means 43 that supplies the electrode part 3. Further, the drying control unit 29 utilizes the centrifugal force by rotating the suction plate 5 according to the suction shaft 17 in addition to the method of drying the cleaning liquid 32 by supplying the discharge voltage to the discharge electrode unit 3 described above. In addition, a scattering removal means 44 for scattering most of the cleaning liquid 32 from the suction plate 5 is also provided.

  For the actual measurement voltage measuring means 39, the electrostatic precipitator 1 of the present embodiment is provided with a voltage measurement sensor (not shown) for measuring the voltage between the discharge electrode portion 3 and the suction plate 5. Yes. In addition, although not shown in figure, the electric power for functioning the drive motor 15 of the airflow generation part 16, the plate rotation motor 21 of the collection part 22, the discharge voltage supply part 31, the suction surface washing | cleaning part 36, and the main control part 37, respectively. In order to supply (voltage), the electrostatic precipitator 1 of this embodiment is connected to a commercial power source.

  Here, the airflow generation unit 16 corresponds to the airflow generation unit in the present invention, the plate rotation motor 21 corresponds to the plate rotation unit in the present invention, and the collection unit 22 corresponds to the collection unit in the present invention. The section 30 corresponds to the discharge means in the present invention, and the discharge voltage supply section 31 corresponds to the discharge voltage supply means in the present invention.

  Further, the electric dust collector 1 of the present embodiment will be described in detail. The housing 12 having a substantially rectangular parallelepiped housing shape has an intake port 8 opened on one end side of the housing upper surface 12a. Is formed so as to have an exhaust port 10 opened on the other end side of the housing upper surface 12a. Further, the air passage 11 is roughly divided into three sections 45a, 45b, and 45c between the intake port 8 and the exhaust port 10. More specifically, a first section 45a that is connected to the intake port 8 and guides the contaminated air 7 sucked from the intake port 8 to the discharge electrode unit 3 of the discharge section 30, and downstream of the first section 45a. Provided on the side, the second section 45b in which the discharge section 30 and the collection section 23 are accommodated, and provided on the downstream side of the second section 45b, the rotary fan 14 of the airflow generation section 16 is installed at a substantially center, Fine particles 6 are collected by the adsorption plate 5 in the second section 45b, and the third section 45c is configured to be able to discharge the cleaned clean air 9 from the exhaust port 10 opened in the housing upper surface 12a.

  Here, partition walls 46a and 46b are respectively provided between the sections 45a and the like, and in order to distribute the contaminated air 7 or clean air 9 between the sections 45a and the like, the partition walls 46a and 46b are respectively provided. Openings 47a and 47b are formed. Here, the airflow 13 flows so that the openings 47a and 47b flow stably between adjacent sections, for example, between the first section 45a and the second section 45b, and further flow into the vicinity of the center of the discharge electrode section 3. It is designed to be rectified.

  Furthermore, the electrostatic precipitator 1 of this embodiment has an inclined floor surface in which the bottom surface of the housing 12 is inclined in a predetermined direction (here, obliquely downward toward the downstream side of the air passage 11) as another configuration. 48 is formed. Therefore, when the cleaning liquid 32 is sprayed onto the suction surface 18 of the suction plate 5 using the suction surface cleaning unit 36 to be described later and the fine particles 6 are washed away from the suction surface 18, the cleaning liquid 32 containing the fine particles 6 becomes the inclined floor of the housing 12. 48 is finally reached. And it is guide | induced to the lowest position along the inclination of the inclined floor surface 48. FIG. Here, a drain 49 is provided at the lowest position, and the used cleaning liquid 32 can be collected. The recovered cleaning liquid 32 can be reused after removing only the fine particles 6 with a filter or the like.

  In addition, the electric dust collector 1 of this embodiment has a support bracket (not shown) for suspension support for facilitating installation and movement at each of the four corners of the housing upper surface 12a as another configuration. Further, a support leg 51 is provided on the housing lower surface 12b.

  Here, in the present embodiment, an example in which a discharge voltage of about 10000 V is supplied from a discharge voltage supply unit 31 connected to the discharge unit 30 to generate a corona discharge CD will be described. Then, this discharge voltage is transmitted to the discharge electrode portion 3 through the discharge shaft 23 and the charge plate 4, and a potential difference is generated between the charge plate 4 and the suction plate 5 to generate a corona discharge CD from the sharp end portion 28. Yes. In order to generate the corona discharge CD, the configuration other than the discharge unit 30, in particular, the collection unit 23 and the housing 12 are configured in a state of being electrically insulated from the discharge unit 30 by an insulating member or the like. Measures are taken so that the corona discharge CD does not occur from a place other than the discharge electrode portion 3 or leakage due to a high voltage does not occur. Furthermore, the collection part 23 and the housing 12 are connected to a ground (not shown) embedded in the ground so that electricity can escape to the ground. Therefore, the charges of the fine particles 6 collected on the adsorption surface 18 do not always stay in the adsorption plate 5 and the collection unit 23.

  With the above configuration, the discharge unit 30 connected to the discharge voltage supply unit 31 generates a corona discharge CD from the sharp end portion 28 of the discharge electrode unit 3 (see FIG. 4 and the like), while the suction plate 5 is discharged by grounding or the like. It is in a state of being electrically opposed to the electrode part 3. As a result, the fine particles 6 of the contaminated air 7 that has become a positive potential due to the corona discharge CD repel the electrically charged plate 4, and a force to move away from the discharge surface 25 acts on the other hand. The suction plate 5 that is electrically opposed to the formed fine particles 6 attracts the fine particles 6 to the suction surface 18, that is, a force for sucking the fine particles 6 acts. As a result, by continuing the operation of the electrostatic precipitator 1 of the present embodiment for a long time, a large amount of fine particles 6 adhere to the suction surface 18 of the suction plate 5. In addition, the sharp end portion 28 of the discharge electrode portion 3 is formed so as to be insertable into the insertion portion of the discharge electrode portion 3 as shown in FIGS. 3 and 4, and when the tip is worn by the corona discharge CD. It can be exchanged.

  With the above configuration, when the cleaning process of the contaminated air 7 is continuously performed for a long time, a large amount of fine particles 6 are adsorbed on the adsorption surface 18 of the adsorption plate 5. In this case, the influence of the Coulomb force is significantly reduced, and as a result, the dust collection efficiency is also lowered. Therefore, the electrostatic precipitator 1 of the present embodiment has a suction surface cleaning unit 36 for physically removing the collected fine particles 6. As already described, the suction surface cleaning unit 36 is installed so as to be bridged in the width direction of the air passage 11, and has the injection nozzle 34 in which the injection port 33 is directed to each suction surface 18. ing. As for this injection nozzle 34, the injection port 33 is formed in two places of right and left. Therefore, the cleaning liquid 32 sent from the storage tank via the supply hose 35 is divided into two directions by the injection nozzle 34 and injected to the respective suction surfaces 18 of the pair of suction plates 5 facing each other. The fine particles 6 are washed away. In this cleaning home, the generation of corona discharge CD from the discharge electrode unit 3 is stopped, and the suction plate 5 is sucked by the plate rotation motor 21 so that the cleaning liquid 32 is uniformly sprayed onto the suction surface 18. Control to rotate according to 17 is performed. Note that the rotation of the suction plate 5 is rotated at a rotational speed that is normal or higher than usual, as compared with the case where the fine particles 6 are collected using Coulomb force.

  At this time, due to the rotation of the suction plate 5, the cleaning liquid 32 and the fine particles 6 adhering to the suction surface 18 are subjected to the action of centrifugal force and move toward the rotation direction of the suction plate 5. Splashes into the passage 11. At this time, the scattered cleaning liquid 32 or the like immediately falls downward according to gravity, reaches the inclined floor surface 48 of the housing 12, and is collected from the drain 49.

  Next, drying in the air passage 11 after cleaning in the electric dust collector 1 of the present embodiment will be described. Here, the collection unit 22 such as the suction plate 5 and the discharge unit 30 such as the discharge electrode unit 3 in the air passage 11 have already been wetted by the cleaning liquid 32 in the air passage 11, and the collection unit 22 and the discharge unit 30 are electrically connected. An example of drying from a short-circuited state is shown.

  First, the plate rotation motor 21 of the collection unit 22 is operated to rotate the suction plate 5 in the air passage 11. As a result, the cleaning liquid 32 adhering to the suction plate 5 is subjected to centrifugal force as it rotates, and gradually reaches the plate edge 52 from the center of the suction plate 5 by the same action as in the cleaning described above, and finally Are scattered from the plate edge 52 toward the air passage 11 (step S1: plate rotation control step). As a result, most of the cleaning liquid 32 is removed from the suction plate 5.

  Then, a discharge voltage (10000 volts) for generating the corona discharge CD is supplied from the discharge voltage supply unit 31 for a preset unit time (here, set to 0.5 s) (step S2: limited voltage supply) Process). As a result, the process of generating the corona discharge CD from the discharge electrode unit 3 through the discharge shaft 23 connected to the discharge voltage supply unit 31 is performed. However, since the discharge unit 30 and the collection unit 22 are short-circuited by the cleaning liquid 32 in such a state, a sufficient corona discharge CD cannot be generated as it is. In this state, a current flows through the cleaning liquid 32, and the temperature of the cleaning liquid 32 rises due to the generated resistance heat. Alternatively, a spark such as an incomplete corona discharge CD may be generated from the discharge electrode portion 3 partially dried. Such short-circuits or sparks frequently occur mainly in the vicinity of the discharge electrode portion 3 and in the vicinity of the discharge shaft 23 and the suction plate 5 that support the charge plate 4. As a result, the air passage 1 is gradually dried by the temperature rise of the cleaning liquid 32 or the evaporation of the cleaning liquid 32 in contact with the spark. Here, since the supply of the discharge voltage is limited to a preset very short unit time, an excessive load is not applied to the electric circuit of the discharge voltage supply unit 31, and the electric dust collector 1 itself The safety circuit provided in the system does not operate.

  And the actual measurement voltage value between the discharge electrode part and adsorption | suction plate at this time is measured (step S3: actual measurement voltage measurement process). That is, if the inside of the air passage 11 is dry and a complete corona discharge CD is generated, the measured voltage value measured should approximate the supplied discharge voltage. On the other hand, when the discharge voltage is supplied in a short-circuit state wet with the cleaning liquid 32, the measured voltage value is expected to be small. Therefore, the measured voltage value is measured, and further, it is determined whether or not the value exceeds a start reference voltage value that can sufficiently charge the fine particles 6 by the corona discharge CD (step S4: measured voltage value determining means).

  Here, when the measured voltage value measured exceeds the start reference voltage value (YES in step S4), the discharge voltage supply unit 31 is controlled again, and the discharge voltage for generating the corona discharge CD is set to the discharge electrode unit. 3 is continuously supplied (step S5), the air flow generation unit 16 is further controlled to start intake of the contaminated air 7 from the intake port 8, and the particulates 6 are collected using the Coulomb force (step S6). ). That is, the fact that the actually measured voltage value exceeds the start reference voltage value indicates that the electrical voltage is again applied between the collection unit 22 such as the suction plate 5 in the air passage 11 and the discharge unit 30 such as the discharge electrode unit 3. This indicates that the insulation state has been established, and this makes it possible to completely generate the corona discharge CD. Therefore, by continuously supplying the discharge voltage from the discharge voltage supply unit 31 and generating the air flow 13 in the air passage 11 by the air flow generation unit 16, a normal cleaning process of the contaminated air 7 can be performed. Become. That is, the electrostatic precipitator 1 can be restarted in conjunction with the confirmation of the dry state in the air passage 11. Here, step S5 and step S6 correspond to the restarting process of the present invention.

  On the other hand, when it is determined that the measured voltage value is smaller than the start reference voltage value (NO in step S4), the process returns to step S2, and the discharge voltage is supplied again for a predetermined unit time. Such a process corresponds to the re-drying step of the present invention. As a result, the cleaning liquid 32 that could not be sufficiently evaporated in the first limited voltage supply step can be heated again with current, spark, etc., and evaporated. In addition, the process from step S2 to step S4 is performed at a predetermined interval until the actually measured voltage value exceeds the start reference voltage value. Thereby, the operator of the electrostatic precipitator 1 only has to operate the switch that performs the control related to the drying and reactivation at the beginning, and the process from the confirmation of the completion of the drying to the reactivation is performed by the electrostatic precipitator 1. It can be done automatically.

  The present invention has been described with reference to preferred embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention as described below. And design changes are possible.

  That is, the electrostatic precipitator 1 of the present embodiment has a substantially rectangular parallelepiped shape, and the suction surface cleaning unit 36 of the electrostatic precipitator 1 has the injection nozzle 34 arranged in the vicinity of the center of the housing 12. However, the present invention is not limited to this, and the position of the injection nozzle 34 may be changed. Furthermore, the cleaning liquid 32 to be used does not contain a surfactant and may be simple water. Furthermore, in the electrostatic precipitator 1 of this embodiment, what has a substantially rectangular parallelepiped external shape and forms the air passage 11 in a substantially U-shape has been shown. However, depending on the installation environment, the shape of the air passage May be appropriately changed.

  Further, although the cleaning is performed by washing the fine particles 6 from the adsorption surface 18 only by the liquid pressure of the cleaning liquid 32, the present invention is not limited to this, and the fine particles 6 that are strongly adsorbed on the adsorption surface 18 are supported. In addition, a configuration such as a wiper may be provided that includes a suction surface cleaning unit that physically scrapes off the suction surface 18 together with the cleaning liquid 32.

  Moreover, although the thing which makes the drying control part 29 function after the washing | cleaning by the washing | cleaning liquid 32 was shown in the electrostatic precipitator 1 of this embodiment, it is not limited to this. That is, when the electrostatic precipitator 1 is started, that is, when the operation is started, the control by the drying control unit 29 may be performed. Here, the work of the day is over, the operation of the electrostatic precipitator 1 is stopped, and the moisture remaining in the air passage 11 until the next day after starting again becomes moisture, which may result in the short circuit state described above. Therefore, by performing the warm-up operation by the drying control unit 29 at the time of starting, it is possible to prevent the short circuit of the electric circuit due to the high voltage.

  Furthermore, the electrostatic precipitator 1 of this embodiment can perform the process which restarts automatically by the self-diagnosis program provided in the main control part 37, when a high voltage is detected at the time of normal driving | operation. That is, for some reason, when a short circuit occurs between the suction plate 5 and the discharge electrode unit 3 during operation of the electrostatic precipitator 1, the safety circuit of the main body of the electrostatic precipitator 1 acts and restarts again. I do. At this time, similarly to the warm-up operation described above, the drying control unit 29 is controlled to perform the drying process. As a result, the discharge voltage that can sufficiently generate the corona discharge during operation is lower than the preset start reference voltage value, and the trouble is caused by the influence of moisture or the like in the air passage 11. This can be solved by starting the electrostatic precipitator 1 again.

  Furthermore, the electrostatic precipitator 1 according to the present embodiment is configured so that the drying control process as described above can be performed after cleaning, at startup, and when an abnormality occurs, so that the suction plate 5 can be cleaned safely. And can be done quickly. That is, compared with the conventional electrostatic precipitator in which the cartridge type filter is replaced, the electrostatic precipitator 1 of the present embodiment can remarkably shorten the time required for restart. For example, when the electrostatic precipitator 1 of this embodiment is provided to collect smoke generated at a yakiniku restaurant, the suction plate 5 is very dirty, so it needs to be cleaned once every hour. May be. In other words, in places where it is necessary to clean several times to several tens of times per day, it is not possible to change the filter as frequently as in the past. Could not get. On the other hand, according to the electrostatic precipitator 1 of the present application, the cleaning liquid 32 is scattered by the centrifugal force caused by the rotation of the suction plate 5 during cleaning, and a high voltage is supplied at a very short interval to heat the cleaning liquid 32. Or, it can be evaporated in a short time by spark, so that the time for drying can be significantly shortened compared to the past, and it can continue to operate for a long time with high dust collection efficiency maintained. it can. As a result, the electrostatic precipitator 1 that does not deteriorate over a long period of time while maintaining the initial dust collection performance can be obtained.

It is explanatory drawing seen from the side which shows typically the structure inside the electrostatic precipitator of this embodiment. It is explanatory drawing seen from the upper side which shows typically the structure inside an electrical dust collector. FIG. 2 is a schematic cross-sectional view taken along the line AA of FIG. 1 schematically showing the internal configuration of the electric dust collector. It is an expansion explanatory view which expands and shows the principal part composition of a discharge electrode part, a charge plate, and a suction plate. It is a block diagram which shows the functional structure of a main control part. It is a flowchart which shows the flow of a process of the drying control method of an electrical dust collector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric dust collector 2 Electric dust collector drying control method 3 Discharge electrode part 4 Charging plate 5 Adsorption plate 6 Fine particle 7 Contaminated air 8 Intake port 9 Clean air 10 Exhaust port 11 Air passage 12 Housing 13 Air flow 16 Air flow generation part ( Airflow generation means)
17 Adsorption shaft 18 Adsorption surface 21 Plate rotation motor 22 Collection part (collection means)
23 Discharge axis 25 Discharge surface 28 Sharp end 29 Drying control unit 30 Discharge unit (discharge means)
31 Discharge voltage supply unit (discharge voltage supply means)
32 cleaning liquid 33 injection port 34 injection nozzle 36 suction surface cleaning unit 38 limited voltage supply means 39 actual measurement voltage value measurement means 41 actual measurement voltage value determination means 42 reactivation means 43 redrying means 44 scattering removal means CD corona discharge

Claims (3)

A housing in which an air passage that communicates an intake port that sucks contaminated air containing fine particles and an exhaust port that discharges clean air from which the fine particles have been removed; and
An air flow generating means for generating an air flow in the air passage, and performing intake of the contaminated air and exhaust of the clean air;
The suction shaft, which is provided in the air passage and is orthogonal to the flow direction of the airflow, has a substantially disk shape and is attached to the suction shaft with the suction surfaces facing each other. A plurality of adsorption plates that adsorb and collect the charged fine particles using the Coulomb force on the adsorption surface, and one end of the adsorption shaft, and rotate the adsorption plate according to the adsorption axis Collection means comprising suction plate rotation means;
A discharge shaft that is provided in the air passage and is orthogonal to the flow direction of the airflow, and is supported by the discharge shaft and inserted between the pair of suction plates facing each other. A plurality of charged plates disposed in a state where a discharge surface is brought close to the suction surface of the suction plate and is electrically insulated from the suction plate; A discharge means comprising a plurality of discharge electrode portions each having a sharp tip formed with a sharp tip, and charging the fine particles contained in the contaminated air by corona discharge;
A discharge voltage supply means electrically connected to the discharge shaft of the discharge means and supplying a discharge voltage capable of generating the corona discharge from the discharge electrode portion;
A plurality of injection nozzles provided in the air passage and having injection ports directed to the respective adsorption surfaces of the adsorption plate, and connected to the injection nozzles, and the fine particles adsorbed on the adsorption surfaces from the injection nozzles In order to perform cleaning with the jetted cleaning liquid, the suction surface cleaning unit including cleaning liquid supply means that pumps and supplies the cleaning liquid into the air passage;
The cleaning liquid is removed from the collection means including the suction plate cleaned by the suction surface cleaning section and the discharge means including the discharge electrode section where the cleaning liquid is scattered, and the corona discharge in the air passage is removed. In the electrostatic precipitator comprising a drying control unit that dries the generation to a possible state,
The drying control unit
Limited voltage supply means for controlling the discharge voltage supply means and supplying the discharge voltage that can generate the corona discharge to the discharge electrode unit by limiting the discharge voltage to a preset unit time;
When the discharge voltage is supplied to the discharge electrode portion by the limited voltage supply means, the suction plate on which the cleaning liquid remains is rotated according to the suction shaft, and the cleaning liquid is removed from the suction plate using centrifugal force. Scattering removal means for scattering;
Actual voltage value measuring means for measuring an actual voltage value when the discharge voltage is supplied between the discharge electrode portion to which the discharge voltage is supplied and the suction plate;
The measured voltage value determining means for determining whether the measured voltage value measured exceeds a starting reference voltage value capable of charging the fine particles by the corona discharge;
When the measured voltage value exceeds the start reference voltage value, the discharge voltage supply means is controlled, and the discharge voltage capable of generating the corona discharge is continuously supplied to the discharge electrode unit, and Reactivation means for controlling the air flow generation means, starting the intake of the contaminated air from the intake port, and collecting the fine particles using Coulomb force;
When the measured voltage value is smaller than the start reference voltage value, a re-drying unit is provided that controls the limited voltage supply unit and supplies the discharge voltage to the discharge electrode unit again limited to the unit time. An electric dust collector characterized by that. The starting reference voltage value is
The electrostatic precipitator according to claim 1, wherein the electrostatic precipitator is set to 8000 volts or more and 12000 volts or less . In the drying control method of the electrostatic precipitator using the electrostatic precipitator according to claim 1 or 2 ,
A plate rotation control step of rotating the suction plate wet with the cleaning liquid according to the suction axis;
A limited voltage supply step of controlling the discharge voltage supply means in a state where the suction plate is rotated and supplying a discharge voltage for generating a corona discharge from the discharge electrode portion only to a preset unit time;
An actual voltage value measuring step of cleaning the discharge electrode portion supplied with the discharge voltage and the collected fine particles, and measuring an actual voltage value between the suction plates wet with a cleaning liquid;
An actual voltage value determining step for determining whether the measured actual voltage value exceeds a starting reference voltage value that allows the fine particles to be charged by the corona discharge;
When the measured voltage value exceeds the start reference voltage value, the discharge voltage supply means is controlled, and the discharge voltage capable of generating the corona discharge is continuously supplied to the discharge electrode unit, and A restarting step of controlling the air flow generation means, starting the intake of contaminated air from the intake port, and collecting the fine particles using Coulomb force;
A re-drying step of controlling the limited voltage supply means when the measured voltage value is smaller than the start reference voltage value and supplying the discharge voltage to the discharge electrode unit again for the unit time. A drying control method for an electrostatic precipitator.

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