JP3773764B2 - Liquid processing method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a biological aerobic or anaerobic treatment of organic waste liquid discharged from a sewage treatment process in a sewage treatment plant or a sewage treatment plant, or a drainage process of a food factory or a chemical factory. Sterilization and sterilization treatment of factory waste liquids (including those other than organic waste liquids), treated water, water and sewage water, food, drinking water, etc. in the process of producing clean water, For sterilization / sterilization treatment of each liquid, decolorization, deodorization treatment, and decomposition treatment of refractory substances such as dioxins, environmental hormones, PCBs, etc. that appear when leaching water from a waste incinerator The present invention relates to a liquid processing method to be applied and an apparatus used for carrying out such a processing method.
[0002]
[Prior art]
In the above various applications, various methods such as activated carbon treatment, ozone treatment, membrane treatment and the like have been conventionally known as methods for reusing water and removing trace contaminants, and are being put to practical use. However, with activated carbon treatment, it is possible to adsorb and remove organic pollutants, but there is no sterilizing effect, and it is necessary to frequently replace the activated carbon. In addition, ozone treatment has excellent decolorization, deodorization, and sterilization effects, but has a problem of secondary treatment due to residual ozone. Furthermore, although membrane treatment is excellent from the viewpoint of water treatment, there are problems in that maintenance and management are complicated, cost is high, and waste is generated.
[0003]
The inventors of the present invention have been researching the water treatment as described above, and have proposed a technique such as JP-A-11-253999 as part of the research. In this technique, for example, as a method of killing harmful bacteria contained in a liquid and cleaning the liquid, or reducing the amount of fouling components composed of bacteria or dead bodies contained in the liquid. Therefore, as a method for modifying the fouling component into a state in which aerobic microorganisms can be easily treated biochemically, the liquid is treated by applying high voltage pulse discharge and / or electric field pulse to the liquid. . This technique will be described with reference to the drawings.
[0004]
FIG. 1 is a schematic explanatory view showing a configuration example of a liquid processing apparatus previously proposed by the present inventors. A liquid to be treated is an organic waste liquid, and the organic waste liquid is biologically aerobically treated. The case is assumed.
[0005]
In the apparatus shown in FIG. 1, the organic waste liquid is sent to an activated sludge tank (aeration tank) 1 via a path 7. This activated sludge tank 1 holds a certain amount of activated sludge containing aerobic microorganisms, and the biodegradation action of the aerobic microorganisms oxidizes and decomposes organic matter in the organic waste liquid under aerobic conditions. And water (aerobic treatment process). At the same time, the organic matter in the organic waste liquid is assimilated and activated sludge grows.
[0006]
The treated waste liquid is sent to the sedimentation tank 2 via the path 8 in a state of being mixed with the activated sludge, and is solid-liquid separated into the sedimentation sludge 10 and the supernatant liquid (liquid to be treated) 20. The supernatant 20 is discharged from the path 9 as a liquid to be treated. At this time, if necessary, higher-level treatment such as nitrification denitrification or ozone treatment is performed according to the discharge standard of the discharge destination.
[0007]
A part of the precipitated sludge 10 is returned to the activated sludge tank (aerobic treatment tank) 1 via the return path 11 by the pump 16 and partly preferably all is introduced to the reformer 18 by the pump 17 from the path 12. . The reformer 18 includes a reforming tank 3 and a power source 4, and a rod electrode (+ electrode) 5 and a plate electrode (−electrode) 6 connected to the power source 4 serve as sludge in the reforming tank 3. It is arranged in parallel so as to be immersed. The sludge inside the reforming tank 3 can be considered as a dielectric that exhibits a certain dielectric constant electrically, and the potential difference between the electrodes 5 and 6 is filled with the dielectric between the electrodes 5 and 6. If an electric field is applied, an electric field is formed inside the dielectric (sludge), and when the strength of the electric field exceeds a certain level, dielectric breakdown occurs, and discharge occurs between the electrodes 5 and 6.
[0008]
By forming a high voltage pulse discharge state between the electrodes 5 and 6, the microorganisms and organic substances in the precipitated sludge are modified, and solubilization of the sludge proceeds. In other words, microorganisms are killed and further decomposed by cell destruction to produce low-molecular organic substances and inorganic substances. Organic substances are also reduced to low-molecular substances by decomposition and are easily degradable substances (hereinafter referred to as “modified sludge”). There are things).
[0009]
The modified sludge is returned to the activated sludge tank (aerobic treatment tank) 1 from the return path (return means) 13. In the activated sludge tank 1, the modified sludge is decomposed by aerobic microorganisms as feed.
[0010]
In this way, by forming a circulation system in which some, preferably all, of the sludge is reformed and returned to the activated sludge tank 1, the sludge circulating in the system is reduced in volume and, as a result, discharged as excess sludge. The amount is reduced.
[0011]
[Problems to be solved by the invention]
Normally, when a high voltage is applied between electrodes immersed in a liquid, a corresponding high electric field is formed between the electrodes, electrons are emitted from the cathode surface, and so-called primary avalanche is formed. In this avalanche path of primary avalanche, some residual negative ions (negative ion group) are generated by the adhesion action of electrons and positive ions. The amount of charge in the liquid is a predetermined amount of space charge consisting of the sum of the residual negative ions and the charge that has been present, and the electric field in the liquid is between the electric field consisting of this space charge and the electrode in the first place. A combined electric field is formed by combining with an applied electric field of high voltage applied.
[0012]
When the synthetic electric field becomes sufficiently large, electrons generated by photoionization during the progress of primary avalanche grow as a secondary avalanche toward the center of gravity of the residual ion group. A thin plasma is formed by the primary avalanche and the secondary avalanche. This is a phenomenon called streamer (discharge).
[0013]
This streamer discharge is not always maintained in a stable state, and may change to another discharge state depending on circumstances. For example, there may be a transition from a thin streamer discharge to another form in which a positive column is formed between the electrodes. Naturally, such a transition greatly depends on how the streamer discharge propagates between the electrodes.
[0014]
By the way, in the high voltage processing method as described above, the processing is generally performed in a state where the streamer discharge and the discharge of arc discharge other than the streamer which has changed after the streamer is generated are mixed. However, the processing efficiency in the modification treatment of the liquid to be processed under such circumstances is not always sufficient. In other words, in the case of discharge such as arc discharge, the modification of the liquid to be treated does not proceed sufficiently for a large amount of current to flow and consume a large amount of power, and the desired high voltage treatment effect cannot be obtained. There was a problem. In addition, when arc discharge or the like occurs, there has been a situation in which specific abnormal noise is generated.
[0015]
Next, an example of a conventional discharge circuit will be described with reference to FIG. Reference numeral 30 denotes a high-voltage power source, 31 denotes a high-voltage switch unit, 32a denotes a capacitor, 33 denotes a processing container, and the processing container 33 includes an electrode 5. The processing vessel 33 corresponds to the reforming tank 3 in FIG. 1, and a pulsed (usually rectangular wave) high voltage is supplied to the power source 5. The processing vessel 33 is supplied with a liquid to be processed (not shown) and is reformed by the supplied high voltage pulse discharge. In the conventional discharge circuit, when the conductivity of the liquid to be treated changes, the impedance of the discharge changes, and accordingly, the pulse width or the discharge voltage changes, which affects the processing amount and processing efficiency due to the discharge. there were.
[0016]
Therefore, the present invention has been made in view of the above-described actual situation, and the object thereof is to provide a stable discharge for processing liquid with high efficiency and economically advantageously, and to reduce liquid reforming. It is an object of the present invention to provide a method for treating a liquid that can be sufficiently applied with an amount of electric power, and a useful apparatus for carrying out such a method.
[0017]
[Means for Solving the Problems]
The liquid processing method of the present invention that has achieved the above object is to provide at least a pair of electrodes and immerse at least one of the electrodes in a liquid so that the electrode pair is pulsed. In a liquid processing method for reforming the liquid by supplying electric power and forming a discharge state between the pair of electrodes, the conductivity or impedance of the liquid to be processed is detected, and a high level related to the discharge is detected based on a change in the value. The gist of the present invention is that the operation is performed so as to control at least one of the voltage of the voltage pulse, the pulse width, the distance between the electrodes, and the concentration of the liquid to be treated.
[0018]
In addition, the liquid processing apparatus of the present invention that can achieve the above object includes at least one pair of electrodes, and is arranged so that at least one of the electrode pairs is immersed in a liquid. In a liquid processing apparatus configured to supply a pulsed power to the electrode pair, form a discharge state between the electrode pair, and modify the liquid, a detecting means for detecting the conductivity or impedance of the liquid to be processed; It has a gist in that it is provided with means for controlling at least one of the voltage, pulse width, interelectrode distance, and concentration of the liquid to be treated based on the fluctuation of the value. .
[0019]
The above object of the present invention is to measure the discharge voltage or discharge current to the liquid to be treated, and based on the fluctuation of the value, the voltage of the high voltage pulse related to the discharge, the pulse width, the distance between the electrodes and the concentration of the liquid to be treated. It is also achieved by operating at least one of them.
[0020]
The apparatus configuration for carrying out such a method includes a means for measuring a discharge voltage or a discharge current to the liquid to be treated, and a high voltage pulse related to the discharge based on the measured change in the discharge voltage or discharge current. And an apparatus configured to include at least one of a voltage, a pulse width, a distance between electrodes, and a concentration of a liquid to be processed.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
The present inventors have studied from various angles in order to solve the above problems. As a result, the conductivity or impedance of the liquid to be treated, or the discharge voltage or discharge current to the liquid to be treated is detected, and the voltage, pulse width, interelectrode distance and The present invention has been completed by finding that the above-mentioned object can be achieved brilliantly by operating at least one of the concentrations of the liquid to be treated.
[0022]
Hereinafter, the configuration and operational effects of the present invention will be described in more detail with reference to the drawings. However, the configuration shown below is not intended to limit the present invention, and any change in design based on the purpose described above or below Is also included in the technical scope of the present invention.
[0023]
FIG. 3 is a schematic explanatory view showing an example of an electrode arrangement state and a discharge state when the high-voltage pulse discharge process is performed in the reformer 18 of FIG. In FIG. 3, a rod electrode (+ electrode) 5 and a ring electrode (−electrode) 23 are used, and pulsed power is supplied from the power supply 4. In the configuration shown in FIG. 3, the rod electrode 5 and the ring electrode 23 are arranged concentrically so that the liquid to be treated 29 in the reforming tank 3 can be discharged three-dimensionally. Further, in the apparatus shown in FIG. 3, a schematic diagram is shown in which a pair of electrode pairs each composed of the rod electrode 5 and the ring electrode 23 is provided. However, the number of electrode pairs can be two or more. The liquid can be processed efficiently.
[0024]
In the apparatus of the present invention, the discharge treatment function can be exhibited by immersing at least one electrode of the electrode pair in the liquid to be treated as described above, but from the viewpoint of discharge stability, The electrode immersed in the electrode is preferably at least an anode electrode, and more preferably, both the cathode electrode and the anode electrode are immersed.
[0025]
FIG. 4 is a schematic explanatory view schematically showing an example of the configuration of the apparatus according to the present invention, in which the conventional discharge circuit shown in FIG. 2 is detected for detecting the conductivity or impedance of the liquid to be processed. A device 34 is provided. The variable capacitor 32b is used so that the capacitance of the capacitor can be changed based on the fluctuation of the value detected by the detection device 34. The measurement of the conductivity or impedance of the liquid to be processed may be performed either in the processing container 33, before the discharge process (in the path 41), or after the discharge process (in the path 42).
[0026]
When the conductivity of the liquid to be processed increases or the impedance decreases, the time during which the voltage of the discharge pulse waveform drops is shortened or the pulse width is narrowed. As a result, the discharge voltage × time applied to the discharge per time is reduced, and the area that can be processed by the discharge is reduced. The state of the discharge 25 at this time is schematically shown in FIG. In some cases, the battery may not be discharged (not shown).
[0027]
In order to prevent these, at least one of the devices may be controlled as in the following (1) to (4).
(1) Increase the pulse voltage of the high voltage pulse related to the discharge.
(2) Widen the pulse width of the high voltage pulse related to the discharge.
(3) Shorten the distance between the pair of electrodes related to the discharge and increase the electric field strength between the electrodes.
(4) Reduce the concentration of the liquid to be treated.
[0028]
On the other hand, when the conductivity of the liquid to be treated is reduced or the impedance is increased, the time during which the voltage of the discharge pulse waveform falls is increased or the pulse width is increased. As a result, the discharge voltage x time applied to the discharge per time is increased, the streamer discharge is changed to the arc discharge, or the energy ratio of the arc discharge is increased as compared with the streamer discharge, and wasteful energy is processed. It will be thrown into the liquid. The state of the discharge 25 at this time is schematically shown in FIG. FIG. 6 shows a state where some of the streamer discharges 26 are transferred to the arc discharge 27 and the streamer discharge 26 and the arc discharge 27 are mixed.
[0029]
In order to prevent these, at least one of the devices may be controlled as in the following (5) to (8).
(5) Lower the pulse voltage of the high voltage pulse related to the discharge.
(6) Narrow the pulse width of the high voltage pulse related to the discharge.
(7) Increase the distance between the pair of electrodes related to the discharge to reduce the electric field strength between the electrodes.
(8) Increase the concentration of the liquid to be treated.
[0030]
As described above, according to the present invention, even when the conductivity or impedance of the liquid to be treated is changed, liquid treatment by stable discharge is possible.
[0031]
Hereinafter, each method capable of solving the above-described object will be described in detail.
[0032]
In order to control the high voltage pulse width related to the discharge, the capacity of the variable capacitor 32b is switched based on the change in the conductivity or impedance of the liquid to be treated, or the pulse width is controlled by using the high voltage switch as a switch such as a vacuum tube. It is possible.
[0033]
Further, the distance between the electrodes related to the discharge is such that the electrodes are movable, and the distance between the electrodes is controlled based on the change in the conductivity or impedance of the liquid to be processed. By controlling the distance between the electrodes, the electric field strength between the electrodes can be changed.
[0034]
On the other hand, in order to change the concentration of the liquid to be treated, a method as shown in FIGS. 7 and 8 can be considered.
[0035]
In the conductivity or impedance measurement unit 34, when the conductivity of the liquid to be processed increases or the impedance decreases, the electric conductivity of the liquid to be processed decreases or the impedance increases as shown in FIG. Thus, in the previous stage of the processing container 33, water or a liquid to be processed having a low concentration is added from the path 43 and mixed with the liquid to be processed introduced from the path 40 by the conductivity adjusting unit 35. The conductivity can be controlled.
[0036]
In the conductivity or impedance measuring unit 34, when the conductivity of the liquid to be processed is reduced or the impedance is increased, the conductivity of the liquid to be processed is increased or the impedance is decreased as shown in FIG. As described above, in the previous stage of the processing container 33, a liquid to be processed having a high concentration is added from the path 43, or an electrolyte such as potassium chloride or sodium chloride is added and introduced from the path 40 by the conductivity adjusting unit 35. The conductivity of the liquid to be processed can be controlled by mixing with the liquid to be processed. Further, as shown in FIG. 8, a method may be considered in which a concentration tank 36 is disposed in front of the processing vessel 33, the concentration is adjusted by concentrating the liquid to be processed, and the conductivity is controlled.
[0037]
On the other hand, FIG. 9 is a schematic explanatory view schematically showing another configuration example of the apparatus according to the present invention, and is the same configuration as FIG. 4 except that a voltage detection unit 37 is provided. The high voltage power supply 30 can apply a voltage of several tens of kV or more (preferably about 70 kV). Although the high voltage switch unit 31 shows the mechanical switch configuration in FIG. 9, the high voltage switch unit 31 includes a switching means capable of high repetitive operation such as a cyliteron or a magnetic switch. By using it, the voltage from the high-voltage power supply 30 can be pulsed. Further, at this time, by adopting the switch means, application of a high voltage exceeding a certain value for a predetermined time or more is not allowed. The voltage detector 37 detects a potential difference (voltage) at the processing container 33 (load side).
[0038]
In the apparatus configuration shown in FIG. 9, the voltage applied to the processing container 33 (that is, the voltage applied to the liquid to be processed) is detected by the voltage detector 37, and the value fluctuates by a predetermined amount or more per minute time. If this is recognized, it will show a sign that the streamer discharge changes (or shifts) to arc discharge. Then, during the transition to the arc discharge, by controlling at least one of the voltage of the high voltage pulse, the pulse width, the distance between the electrodes and the concentration of the liquid to be treated, as described above, from the streamer discharge. The transition to arc discharge can be stopped or the transition can be kept to a minimum.
[0039]
In other words, streamer discharge maintains discharge with a high voltage, and arc discharge maintains discharge with low voltage and high current. The voltage between the cathodes will drop rapidly. And by detecting this reduced voltage (for example, about 1 to 10 kV), by controlling at least one of the voltage of the high voltage pulse applied to the discharge, the pulse width, the distance between the electrodes, and the concentration of the liquid to be treated, It is possible to prevent the transition from the streamer discharge to the arc discharge or to minimize the transition to the arc discharge and to avoid the occurrence of the mixed state of the streamer discharge and the arc discharge. Further, by adopting such a configuration, it is possible to sufficiently modify the liquid to be treated with a small amount of electric power, which is highly efficient and economically advantageous. The “minute time” means from several tens of nsec to several hundreds of nsec.
[0040]
FIG. 10 is a schematic explanatory view schematically showing another configuration example of the apparatus according to the present invention, and is the same as the configuration shown in FIG. 9 except that a current detection unit 38 is provided. Accordingly, the pulse forming principle and the mechanism of the high voltage switch unit 31 in the apparatus shown in FIG. 10 are the same as described above.
[0041]
In the apparatus configuration shown in FIG. 10, the current applied to the processing container 33 (that is, the current applied to the liquid to be processed) is detected by the current detector 38, and the value fluctuates by a predetermined amount or more per minute time. Is observed, by controlling at least one of the voltage of the high voltage pulse, the pulse width, the distance between the electrodes and the concentration of the liquid to be treated, to prevent the transition from the streamer discharge to the arc discharge, or Transition can be kept to a minimum.
[0042]
That is, as described above, since the current during streamer discharge is small and the arc discharge is maintained in a state where the current is large, when the streamer discharge is changed to the arc discharge, the current flowing through the processing vessel 33 increases rapidly. It will be. Then, by detecting this increase in current (for example, about 300 to 500 A or more), by controlling at least one of the voltage of the high voltage pulse, the pulse width, the distance between the electrodes, and the concentration of the liquid to be treated. Therefore, the transition from the streamer discharge to the arc discharge can be prevented or the transition to the arc discharge can be minimized, and the occurrence of the mixed state of the streamer discharge and the arc discharge can be avoided.
[0043]
【The invention's effect】
The present invention is configured as described above, and can provide a stable discharge for processing liquid with high efficiency and economically advantageously, and can sufficiently reform liquid with a small amount of electric power. And a useful apparatus for carrying out such a method could be provided.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing a configuration example of a liquid processing apparatus previously proposed by the present inventors.
FIG. 2 is a schematic explanatory view schematically showing an example of a conventional discharge circuit.
FIG. 3 is a schematic explanatory view schematically showing an example of an arrangement state and a discharge state of electrodes according to the present invention.
FIG. 4 is a schematic explanatory view schematically showing a configuration example of an apparatus according to the present invention.
FIG. 5 is a schematic explanatory view schematically showing the state of discharge.
FIG. 6 is a schematic explanatory view schematically showing the state of discharge. FIG. 7 is a schematic explanatory view showing an example for changing the concentration of the liquid to be treated according to the present invention.
FIG. 8 is a schematic explanatory view showing another example for changing the concentration of the liquid to be treated according to the present invention.
FIG. 9 is a schematic explanatory diagram schematically showing a configuration example of an apparatus according to the present invention.
FIG. 10 is a schematic explanatory view schematically showing another configuration example of the apparatus according to the present invention.
[Explanation of symbols]
1 Activated sludge tank (aerobic treatment tank)
2 Settling tank
3 Reforming tank
4 Power supply
5 Bar electrode
6 Plate electrode
7-9, 12, 15, 40-43 route
10 Precipitated sludge
11, 13 Return route
16, 17 pump
18 reformer
20 Supernatant (processed liquid)
23 Ring electrode
24 transducers
25 Discharge
26 Streamer discharge
27 Arc discharge
29 Liquid to be treated
30 High voltage power supply
31 High voltage switch
32a capacitor
32b variable capacitor
33 Processing container
34 Conductivity or impedance measurement section
35 Conductivity adjuster
36 Concentration tank
37 Voltage detector
38 Current detector

Claims (6)

At least one set of electrode pairs is provided, at least one electrode of the electrode pairs is immersed in a liquid, pulsed power is supplied to the electrode pairs to form a discharge state between the electrodes, and the liquid is In the liquid processing method to be modified,
Detect the conductivity or impedance of the liquid to be treated,
When the conductivity of the liquid to be treated is reduced or the impedance is increased, the voltage of the high voltage pulse related to the discharge is reduced , the pulse width is reduced, or the distance between the electrodes is increased to reduce the electrolysis between the electrodes. lower the strength, and is characterized in that to minimize the transition to prevent or arc discharge to shift from the streamer discharge to the arc discharge by performing one of the at least one increasing the concentration of the liquid to be treated Liquid processing method. At least one electrode pair is provided, and at least one of the electrode pairs is arranged to be immersed in a liquid, and a pulsed power is supplied to the electrode pair to form a discharge state between the electrodes. In the liquid processing apparatus configured to modify the liquid,
Detection means for detecting the conductivity or impedance of the liquid to be treated;
When it is detected that the conductivity of the liquid to be treated is reduced or the impedance is increased, the voltage of the high voltage pulse related to the discharge is lowered , the pulse width is reduced, or the electrode distance is increased. lower the electrolytic strength between, and comprising means for controlling to perform at least either increasing the concentration of the liquid to be treated, the transition to prevent or arc discharge to shift from the streamer discharge to arc discharge Liquid processing apparatus characterized by being kept to a minimum . At least one set of electrode pairs is provided, at least one electrode of the electrode pairs is immersed in a liquid, pulsed power is supplied to the electrode pairs to form a discharge state between the electrodes, and the liquid is In the liquid processing method to be modified,
Measure the discharge voltage or discharge current to the liquid to be treated,
When a decrease in discharge voltage or an increase in discharge current that occurs when transitioning from streamer discharge to arc discharge is detected, the voltage of the high voltage pulse related to discharge is reduced , the pulse width is reduced, or the distance between electrodes minimizing the transition to prevent or arc discharge to shift from the streamer discharge to the arc discharge by performing either lengthen lower the electric field strength between the electrodes, and either increasing the concentration of the liquid to be treated either at least A liquid processing method characterized by being limited to a limit . At least one electrode pair is provided, and at least one of the electrode pairs is arranged to be immersed in a liquid, and a pulsed power is supplied to the electrode pair to form a discharge state between the electrodes. In the liquid processing apparatus configured to modify the liquid,
Means for measuring the discharge voltage or discharge current to the liquid to be treated;
When a decrease in discharge voltage or an increase in discharge current that occurs when transitioning from streamer discharge to arc discharge is detected, the voltage of the high voltage pulse related to discharge is reduced , the pulse width is reduced, or the distance between electrodes To prevent the transition from the streamer discharge to the arc discharge, or to control to reduce the electrolytic strength between the electrodes by increasing the length of the electrode and / or to increase the concentration of the liquid to be treated. A liquid processing apparatus characterized by minimizing a transition to electric discharge . At least one set of electrode pairs is provided, at least one electrode of the electrode pairs is immersed in a liquid, pulsed power is supplied to the electrode pairs to form a discharge state between the electrodes, and the liquid is In the liquid processing method to be modified,
Detect the conductivity or impedance of the liquid to be treated,
If the conductivity of the liquid to be processed increases or the impedance decreases, the voltage of the high voltage pulse related to the discharge is increased, the pulse width is increased, or the distance between the electrodes is shortened. The liquid treatment is characterized in that the area that can be treated by the discharge is reduced or the discharge is stopped by increasing the electrolytic strength of the liquid and / or reducing the concentration of the liquid to be treated. Method. At least one electrode pair is provided, and at least one of the electrode pairs is arranged to be immersed in a liquid, and a pulsed power is supplied to the electrode pair to form a discharge state between the electrodes. In the liquid processing apparatus configured to modify the liquid,
Detection means for detecting the conductivity or impedance of the liquid to be treated;
When it is detected that the conductivity of the liquid to be treated has increased or the impedance has decreased, the voltage of the high voltage pulse related to the discharge is increased, the pulse width is increased, or the distance between the electrodes is decreased. Means to increase the electrolytic strength between the electrodes and / or lower the concentration of the liquid to be processed are provided to prevent the area that can be processed by the discharge from becoming smaller or from stopping the discharge. A liquid processing apparatus.

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