JP2007069108A - Discharge treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge treatment system which can perform stable and efficient treatment by taking appropriate measures for various disturbance factors. <P>SOLUTION: This discharge treatment system uses discharge units 2a, 2b, 2c comprising electrode parts 4a, 4b, 4c disposed in a liquid to be treated, and feeder parts 6a, 6b, 6c for supplying electricity to the electrode parts. A plurality of the discharge units are disposed, and when at least one of the discharge units is stopped, the remainder of the discharge units makes up for the shortage of discharge energy. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a discharge treatment system that performs various treatments by discharging in a liquid, and more specifically, sterilization of water, sterilization and inactivation of microorganisms, destruction and inactivation of algae, aquatic organism tanks and facilities The present invention relates to an electric discharge treatment system used for preventing or removing adhesion of a liquid.

  When a voltage higher than the dielectric breakdown voltage of water is applied between electrodes immersed in water, discharge occurs between the electrodes. It is known that ultraviolet rays and shock waves are generated with this discharge, and these are various treatments in water, for example, sterilization of water, sterilization of microorganisms, inactivation, removal of deposits on tanks and facilities. It can be used for prevention, destruction and inactivation of algae.

  By the way, the situation where such a device is used is often a harsh environment for a precise device, which may cause a malfunction or failure of the device. Therefore, a system in which a predetermined sensor is provided and the apparatus is adjusted as necessary has been studied. In addition, such a device also needs to be stopped quickly in order to prevent an accident if a serious failure occurs. However, it is expected that such an apparatus is often operated automatically in an unattended state. In such a case, if the apparatus is frequently stopped, the efficiency of the work is greatly reduced. .

JP 2004-89874 A

  The present invention has been made in view of the above circumstances, and a discharge processing system capable of performing stable and efficient processing over a long period of time by taking appropriate measures in preparation for various disturbance factors. The purpose is to provide.

  In order to achieve the object, the discharge processing system according to claim 1 is a discharge processing system that uses a discharge unit that includes an electrode unit disposed in a liquid to be processed and a power supply unit that supplies power to the electrode unit. Then, a plurality of the discharge units are installed, and when at least one of the plurality of discharge units is stopped, the discharge energy that is deficient by the remaining discharge units is compensated.

  According to the first aspect of the invention, the remaining discharge units of the plurality of discharge units make up for the insufficient discharge energy, so that the operation is continued while maintaining the necessary discharge energy without replacement or repair. be able to.

The discharge treatment system according to claim 2 is a discharge treatment system that uses a discharge unit having an electrode portion disposed in a liquid to be treated and a power feeding portion that feeds power to the electrode portion. A plurality of at least one of the units is installed, and when at least one of the plurality of electrode units or the power feeding unit stops, the connection between the remaining electrode units and the power feeding unit can be switched.
According to the second aspect of the present invention, the operation can be continued with the optimum combination according to the situation by switching the connection between the remaining electrode unit and the power feeding unit.

According to a third aspect of the present invention, there is provided a discharge processing system according to the first or second aspect, further comprising failure determination means for determining a failure of the discharge unit.
According to the first aspect of the present invention, it is possible to quickly take measures such as stopping the discharge unit that has been determined by the failure determination means to have a failure or its risk.

According to a fourth aspect of the present invention, there is provided the discharge processing system according to the third aspect, wherein the failure determination means is one or more of an electric discharge detection means, a physical discharge detection means, and an electrode interval detection means. The determination is made based on the detection result.
According to the fourth aspect of the present invention, it is possible to accurately determine at which part of the discharge unit a failure has occurred or there is a risk thereof.

According to a fifth aspect of the present invention, in the discharge treatment system according to any one of the first to fourth aspects, the discharge unit is installed in a pipe through which a fluid to be treated flows. .
According to a sixth aspect of the present invention, there is provided the discharge processing system according to any one of the first to fourth aspects, wherein the discharge unit is installed in a storage portion in which a fluid to be processed stays. .

  According to the discharge processing system of the first to sixth aspects, the operation can be continued while maintaining the necessary discharge energy without replacing or repairing the failed device. Therefore, it is possible to improve the operating efficiency of the processing apparatus using this system, that is, to perform a stable and highly efficient operation for a long time, which is particularly advantageous in the case of unmanned operation.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a water purification system in which the discharge treatment system of the present invention is installed. In this water purification system, a flocculant is added to the raw water 70 supplied from a river, a well, etc., and then stirred and mixed in the rapid mixing basin 72 and slow mixing ponds 74a and 74b, and coagulated and precipitated in the settling tank 76. The treated water is further sent to the filter basin 78, and the floating solid is filtered by a filter medium 80 such as sand or a membrane and sent from the distribution reservoir 82 to the subsequent process.

  In the filtration basin 78, in order to eliminate clogging of the filter medium 80, a reverse cleaning device 84 is provided for cleaning the filter medium 80 intermittently with a reverse water flow. The reverse cleaning device 84 includes a pump 86 for causing the washing water to flow back to the filtration basin 78, a drainage basin 88 that receives the backwashing water, a drainage basin 90 that receives sediment in the drainage basin 88, and a drainage basin 88. And a pump 94 for returning the supernatant liquid to the rapid mixing basin 72 via the return pipe 92. The supernatant liquid of the drainage basin 90 is returned to the drainage basin 88 by the return pump 96.

  The return pipe 92 is provided with a discharge treatment system A for sterilizing and inactivating pests and algae such as Cryptosporidium and Escherichia coli which are captured in the filter medium 80 and backflowed by backwashing. As shown in FIG. 2, the discharge processing system A includes three discharge units 2a, 2b, and 2c provided in a series direction in a pipe 10 (part of a return pipe 92). , 2b, 2c have electrode portions 4a, 4b, 4c and power supply portions 6a, 6b, 6c for supplying power to the electrode portions 4a, 4b, 4c. Each of the power supply units 6a, 6b, and 6c includes a power supply circuit 20 and a power supply control unit 26 as shown in FIG. Furthermore, the discharge processing system A includes a control unit 8 that controls the three discharge units 2a, 2b, and 2c.

  As shown in FIG. 3, each electrode portion 4a, 4b, 4c has a pair of rod-like or plate-like high-voltage side electrode 12 and ground-side electrode 14 inserted through the left and right side walls and a predetermined gap at the center of the pipe 10. They are arranged so as to face each other so as to form G. The high voltage side electrode 12 is supported via the power supply support portion 18 and connected to the high voltage output terminal of the power supply circuit 20 of the power supply portions 6a, 6b, 6c. The ground side electrode 14 is grounded via an ammeter 16. These ground-side and high-voltage-side electrodes 12 and 14 are inserted into the pipe 10 through a seal mechanism (not shown), and the horizontal plane passing through the axis of the pipe 10 by the electrode drive mechanisms 22a and 22b provided outside the pipe 10. It can be moved back and forth inside.

  As shown in FIG. 2, open / close switches S1, S2, and S3 are provided on the power supply lines connecting the power supply units 6a, 6b, and 6c to the electrode units 4a, 4b, and 4c, and the power supply units 6a, 6b, and 6c are provided. There are provided contact switches S12, S23, and S13 for connecting the output lines to each other. These switches are also controlled to be opened and closed by the control unit 8.

  As shown in FIG. 4, the power feeding circuit 20 includes a power supply 28, a transformer (transformer) 30 that boosts the power supply voltage to a charging voltage, and a switching element (IGBT) that is disposed on the primary side of the transformer 30 and turns on / off charging. ) 32, a charging capacitor 34 disposed on the secondary side of the transformer 30, and a voltmeter 36 disposed in parallel with the charging capacitor 34 to detect the state of charge. The ground side terminal of the capacitor 34 is connected to the ground side electrode 14 via the ammeter 16, and the high voltage side terminal of the capacitor 34 is connected to the high voltage side electrode 12. The output voltage of the transformer 30 is set to an appropriate value higher than the dielectric breakdown voltage of the liquid to be processed.

  In this discharge treatment system A, the discharge energy (= w) loaded per unit amount of water necessary for performing sterilization and inactivation treatment of pests and algae is determined in advance. Therefore, in a state in which the three discharge units 2a, 2b, and 2c are constantly operated, each discharge unit 2a, 2b, and 2c has a discharge energy (= (1/3) w · v, where v is the flow velocity). However, the ratings of the discharge units 2a, 2b, 2c are (1/2) w · v or more so that even two units can cover this.

  The control unit 8 controls the power feeding units 6a, 6b, and 6c of the three discharge units 2a, 2b, and 2c, and supplies a predetermined discharge power to each of the discharge units 2a, 2b, and 2c at a predetermined pitch. To discharge. Depending on the case, the discharge pitch may be determined evenly by taking into account the flow rate of the water to be treated and by appropriately shifting the discharge timing.

  In the discharge units 2a, 2b, and 2c configured as described above, the feed control unit 26 turns on the switching element 32 connected to the power source 28 at a predetermined timing while the water to be treated flows through the pipe 10. As a result, the voltage boosted by the transformer 30 is applied to the capacitor 34 to charge the capacitor 34. As long as the charging voltage is smaller than the dielectric breakdown voltage of the liquid to be processed in the pipe 10, no discharge occurs and the voltage is simply loaded between the electrodes 12 and 14. When the charging voltage exceeds the dielectric breakdown voltage of the liquid to be treated, a streamer discharge state in which several streaked ionization discharge paths extend between the electrodes 12 and 14 is obtained. When the charging further proceeds and the charging voltage rises, one thick discharge path is formed, and arc discharge accompanied by evaporation of the liquid to be processed and a shock wave is generated, and the stored energy of the capacitor 34 is consumed and the charging voltage is increased. Returns to the initial low voltage state. The pitch of the discharge is performed by controlling the switching element 32. In this example, the process is based on arc discharge, but in order to continue the streamer discharge without causing the arc discharge, the discharge voltage may be set so as to maintain the streamer discharge.

  When the current flowing into the ground electrode is detected by the ammeter 16 and this is equal to or greater than a predetermined lower limit value Imin, it is estimated that discharge has occurred between the electrodes. That is, the ammeter 16 is means for electrically detecting discharge. In addition, this apparatus is provided with a physical discharge detecting means for physically detecting the discharge. That is, vibration sensors 24 a and 24 b on the ground side and the high voltage side are provided on the side wall portion of the pipe 10 in the vicinity of the insertion positions of the electrodes 12 and 14, respectively. In this case, discharge in water is detected as vibration, but when the discharge is accompanied by generation of light, a light detection means may be used, and other appropriate sensors can be used. Output signals from the left and right vibration sensors 24a and 24b, the voltmeter 36, and the ammeter 16 are input to the power supply control unit 26. The power supply control unit 26 also includes a switching element 32, electrode drive mechanisms 22a and 22b, and a power source. Each control signal is output to 28.

  The power supply control unit 26 can use the time from when the measured voltage of the voltmeter 36 reaches a predetermined voltage until the occurrence of discharge (referred to as voltage maintenance time) as a value for determining the electrode interval. That is, since there is a fixed relationship between the voltage maintaining time T and the electrode interval D, the control unit and the voltmeter 36 constitute an electrode interval detection means. Since the relationship between the voltage maintaining time T and the electrode interval D varies depending on the operating conditions of the apparatus, the properties of the liquid to be treated, and the like, it is preferable to obtain it experimentally before starting the treatment. Note that the occurrence of discharge can be electrically detected by the voltmeter 36 and the ammeter 16.

  In order to perform an appropriate discharge, the electrode interval D needs to be in an appropriate range. That is, if the electrode interval D is less than or equal to the lower limit value Dmin, the discharge occurs before the required charge voltage is reached, and if the electrode interval D exceeds the upper limit value Dmax, the discharge timing may be delayed or excessive Thus, an excessive discharge current flows or no discharge occurs. Such a normal range of electrode spacing (Dmax> D> Dmin) is also considered to vary depending on the properties of the liquid to be treated, the discharge pattern, etc., and is preferably obtained in advance by a test or the like. Usually, as the process proceeds, the electrode interval often increases due to electrode wear or the like, but may decrease due to deposition on the electrode surface or the like. The control unit can monitor such a change in the electrode interval by detecting the voltage maintaining time T.

  The power supply control unit 26 determines the operating status of the discharge units 2a, 2b, and 2c based on the combination of the determination results of the electrical discharge detection unit, the physical discharge detection unit, and the electrode interval detection unit. If a failure occurs in any one of the discharge units 2a, 2b, 2c, the control unit 8 determines a response based on information from the power supply control unit 26. If it is determined that there is a problem that the operation should not be continued, the operation is completely stopped, and the return pipe 92 is closed and the back washing operation is stopped, or a warning is issued. Take measures such as

  Further, for example, when the electrode interval of the discharge units 2a, 2b, 2c is out of the range and can be adjusted, a drive signal is sent to the electrode drive mechanisms 22a, 22b so that the electrode interval is within the range. Continue driving. Further, for example, when there is a failure in one discharge unit 2a, control is performed so that the remaining two discharge units 2b and 2c can be operated and discharge processing at the same energy level can be performed. . Such a control method is effective especially when driving unattended at night. Hereinafter, the process in such a case will be described.

  Normally, as shown in FIG. 2A, the open / close switches S1, S2, S3 of the discharge units 2a, 2b, 2c are turned on, and the communication switches S12, S23, S13 between the discharge units 2a, 2b, 2c are turned on. The discharge units 2a, 2b, 2c are individually operated with the power turned off. Here, when a failure occurs in the electrode unit 4a or the power supply unit 6a of the discharge unit 2a, the control unit 8 stops the operation of the power supply unit 6a and turns off the open / close switch S1. If possible, the electrode driving mechanisms 22a and 22b (FIG. 3) are operated to retract the electrodes 12 and 14 from the central portion of the pipe 10. And the control part 8 controls the electric power feeding parts 6b and 6c so that the discharge amount in the remaining two discharge units 2b and 2c becomes 1.5 times, respectively. In the apparatus of FIG. 4, for example, the discharge cycle can be increased by 1.5 times by advancing the opening and closing timing of the switching element 32, and the continuous operation can be performed while maintaining the amount of power required for the processing. In this way, the operation is continued, and after the immediate back cleaning operation is completed, the failed discharge unit 2a may be removed, repaired, replaced, or the like.

  In the above-described embodiment, the three discharge units 2a, 2b, and 2c are installed. However, in the case of two units, in order to maintain the same amount of discharge energy after one unit stops, the remaining unit must be operated with twice as much discharge energy as in normal operation. Performance that is significantly higher than required is required. That is, in the case of two units, it is necessary to operate at half of the rating during steady operation, which is disadvantageous in terms of cost. Conversely, if the number is large, high rated performance is not necessary, but the equipment cost increases. Therefore, about 3 to 6 discharge units 2a, 2b, and 2c are most economical.

  For example, the present invention can be used even when the discharge units 2a, 2b, and 2c are frequently stopped (failed) and the discharge energy of the discharge units 2a, 2b, and 2c cannot be completely supplemented. For example, when three discharge units 2a, 2b, and 2c are operated at three-quarters of their respective ratings, when one unit is stopped, the other two units are operated at the rated value even when operating at the rated level. Only 8/9 can be covered. In that case, a flow rate adjusting valve is installed in the return pump or the return pipe 92 so that the amount of water can be adjusted, and when one unit stops, the control unit 8 operates these adjusting mechanisms to Is reduced to 8/9, the operation can be continued with the same discharge energy.

  In the above example, the failed discharge unit 2a is completely disconnected and supplemented by the other discharge units 2b, 2c. However, the failure may be caused by the power feeding units 6a, 6b, 6c or the electrode units 4a, 4b, It is also possible to identify the 4c side, cut off only the failed part, and use the part that has not failed. For example, when the electrode unit 4a of the discharge unit 2a and the power supply unit 6c of the discharge unit 2c fail, as shown in FIG. 2B, the open / close switch S1 of the discharge unit 2a is opened, and the discharge unit 2a and the discharge unit 2c are opened. By closing the communication switch S13, the power feeding parts 6a, 6b of the discharge units 2a, 2b, 2c and the electrode parts 4b, 4c of the discharge units 2a, 2b, 2c are connected and the operation is continued with two units. Can do. Note that in which part of the discharge units 2a, 2b, and 2c the failure has occurred is determined based on the combination of the determination results of the above-described electrical discharge detection means, physical discharge detection means, and electrode interval detection means. Can do.

  For example, when the electrode unit 4a of the discharge unit 2a fails, the open / close switch S1 of the discharge unit 2a is opened and the connection switches S12 and S13 are closed, so that the power supply unit 6a switches to the electrode unit 4b or the electrode unit 4c. Power can be supplied. In this case, there is a possibility of interference when two power supply units are connected to the same electrode unit. Therefore, it is necessary to provide a switch for eliminating this, or to shift the power supply phase of the power supply unit 6a to others. Become.

  FIG. 5 shows discharge units 2a, 2b, and 2c according to another embodiment of the present invention, in which the ground side electrode and the high-voltage side electrode of the discharge units 2a, 2b, and 2c It is arranged coaxially inside. That is, the high-voltage side electrode 12A extends along the central axis, and the ground-side electrode 14A is formed in a cylindrical shape surrounding it.

  The high-voltage side electrode 12A is a pair of high-voltage side support members made of a rod-like insulator inserted into the pipe 10 from an opening flange 40 provided on one side (here, the upper side) of the pipe 10 at an interval in the axial direction. Both ends are supported by 42. An end portion of the high-voltage side electrode 12 </ b> A is led out of the pipe 10 by a conducting wire 44 that passes through the high-pressure side support member 42, and is connected to a high-voltage terminal of the power feeding circuit 20.

  The ground side electrode 14A is composed of a pair of divided electrode plates 14a and 14b (not shown) obtained by dividing the cylindrical body into two along the plane including the axis. Each of the divided electrode plates 14a and 14b is supported by a ground-side support member 46 made of a rod-like insulator inserted into the pipe 10 through a pair of opening flanges 40 arranged to face the side of the pipe 10. It is supported. The ground side electrode 14 </ b> A is led out of the pipe 10 by a conducting wire 45 inserted through the ground side support member 46, and is grounded via an ammeter 16 for detecting occurrence of arc discharge or disappearance of streamer discharge. On the side wall of the pipe 10, vibration sensors 24a and 24b that physically detect discharge are provided.

  Each ground-side support member 46 is movable in the horizontal direction within a plane orthogonal to the pipe 10 by electrode drive mechanisms 22 a and 22 b provided outside the opening flange 40. The electrode drive mechanisms 22a and 22b are driving force conversions such as an electric drive actuator such as an electric motor, a fluid pressure drive actuator such as an air cylinder, and a screw feed mechanism that linearly drives a support member as necessary. A mechanism and a servo mechanism for controlling displacement based on the output of a predetermined position detection sensor are provided. In this embodiment, the control method in the case of a failure or the like is basically the same as in the previous embodiment shown in FIG.

  FIG. 6 is a diagram showing a configuration of a water purification facility according to another embodiment using the discharge treatment system of the present invention. In this water purification facility, a treatment pond 98 that destroys and inactivates algae by discharge is installed between the rapid mixing basin 72 and the slow mixing basin 74, and the discharge treatment system A is installed in this. This discharge treatment system A is the same as the case of FIG. 2 to FIG. 4 in that it has three discharge units 2a, 2b, and 2c, but is not installed in the piping but installed in the open stagnant water. Is different. The structure of the electrode portions 4a, 4b, and 4c is basically the same as that described above, but the electrode drive mechanisms 22a and 22b are not provided in order to be immersed in water. The form of discharge in this example is streamer discharge, but the control method in the case of a failure or the like is basically the same as in the previous embodiment shown in FIGS.

It is a figure which shows the whole structure of the water purification facility using the discharge processing system of embodiment of this invention. (A) And (b) is a figure which shows the electric discharge processing system of 1st Embodiment of this invention, respectively. It is a figure which shows the structure of a discharge unit. It is a figure which shows the electric power feeding part which is the principal part of a discharge unit. It is a figure which shows the discharge processing system of other embodiment. It is a figure which shows the structure of the water purification plant of other embodiment using the discharge processing system of this invention.

Explanation of symbols

2a, 2b, 2c Discharge unit 4a, 4b, 4c Electrode part 6a, 6b, 6c Power supply part 8 Control part 10 Piping 16 Ammeter (electric discharge detection means)
24a, 24b Vibration sensor (physical discharge detection means, electrode interval detection means)
26 Power supply control unit (failure determination means)
98 Treatment tank A Discharge treatment system S1, S2, S3 Open / close switch S12, S23, S13 Contact switch

Claims (6)

A discharge treatment system using a discharge unit having an electrode portion disposed in a liquid to be treated and a power feeding portion for feeding power to the electrode portion,
A plurality of the discharge units are installed, and when at least one of the plurality of discharge units is stopped, the discharge processing system is configured to compensate for the discharge energy that is insufficient by the remaining discharge units. A discharge treatment system using a discharge unit having an electrode portion disposed in a liquid to be treated and a power feeding portion for feeding power to the electrode portion,
A plurality of at least one of the electrode unit or the power feeding unit is installed, and when at least one of the plurality of electrode units or the power feeding unit is stopped, the connection between the remaining electrode unit and the power feeding unit can be switched. Discharge treatment system characterized.   The discharge processing system according to claim 1, further comprising a failure determination unit that determines a failure of the discharge unit.   The discharge according to claim 3, wherein the failure determination means makes a determination based on one or a plurality of detection results among an electrical discharge detection means, a physical discharge detection means, and an electrode interval detection means. Processing system.   The discharge processing system according to any one of claims 1 to 4, wherein the discharge unit is installed in a pipe through which a fluid to be processed flows. The discharge processing system according to any one of claims 1 to 4, wherein the discharge unit is installed in a storage portion in which a fluid to be processed is retained.

Images