JPH022631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an ozone generator that involves operational control of an ozone generator and a plurality of ozone air compressors.

[Technical background of the invention and its problems]

There is a tendency to utilize the oxidizing, sterilizing, and decolorizing and deodorizing effects of ozone for human waste treatment, water and sewage treatment, and industrial wastewater treatment. The amount of ozone generated by generators is also increasing. On the other hand, since the flow rate range of the processing fluid changes throughout the year, the minimum flow rate may decrease to about 20% of the maximum flow rate.

There are limits to increasing the amount of ozone generated by one ozone generator due to construction, economical, and handling considerations, and it is practical to install multiple ozone generators to meet the required large amount of ozone. It is true. Also, since it is not efficient for one air compressor to supply air to the ozone generator to cover the entire adjustment range, it is practical to install multiple blowers.

Conventional ozone generators use an air compressor as an air source, for example, with a capacity of 50% of the total air volume.
Set up 2 units of 25% and combine them to 25%
%, 50%, 75%, and 100% air volume is supplied in stages. On the other hand, the ozone generator measures the flow rate of the fluid to be treated and uses the signal from the ratio controller that outputs the required ozone amount signal based on the output signal from the predetermined ratio setting device to select the number of ozone generators in operation. The number of ozone generators to be operated is determined by dividing the required amount of ozone by the minimum amount of ozone generated per unit, and the required number of ozone generators are operated in a preset order. The total ozone gas flow rate at the generator outlet is multiplied by the ozone concentration in the gas after the ozone gas at each ozone generator outlet is collected, and the total ozone generation amount obtained is compared with the required ozone generation amount. It is common practice to control the amount of ozone generated by giving control signals such that the difference becomes zero to the controllers of the respective ozone generators.

The conventional method will be explained with reference to FIG. Figure 1 shows a flowmeter 6 that measures the flow rate of the material to be processed, and a flowmeter 6.
a ratio controller 8 that outputs the required amount of ozone generation f based on the output signal 6a of the output signal 6a and the output signal 7a from the ratio setting device 7 set in advance, and an air compressor 4c with a 50% air volume connected in parallel to each other. 4d, 25% air volume air compressors 4a, 4b, and an air compressor selection device 15 that selects an air compressor based on the output signal 7a from the ratio setting device 7 and outputs an operation command, are connected in parallel to each other. multiple ozone generators 11
ozone gas flowmeters 2a, 2b, ... 2n connected in series with the ozone gas flowmeters 2a, 2b, ... 2n and measuring the flow rate of ozone generated, respectively, and ozone gas flowmeters 2a, 2b, ... 2n and the ozone generator 11a,
11b, . . . , an ozone concentration meter 1 connected in series to measure the concentration of generated ozone, an output signal C' of the ozone concentration meter 1, and an ozone gas flow meter 2.
a, 2b, . . . , a multiplication calculator 3 that performs a multiplication operation by the output signal F' of the adder 16 that totals the output signals of 2n;
, an ozone generation amount controller 13 that adjusts the ozone generation amount depending on the output signal Yo' of the multiplier 3 and the output signal f of the ratio controller 8, and an output signal 13a of the ozone generation amount controller 13. Ozone generator 11
It consists of ozone generator controllers 14a, 14b...14n that control the ozone generators a, 11b...11n, and the number of operating ozone generators is calculated by dividing the output signal f of the ratio controller 8 by the amount of ozone generated per single machine. This shows an ozone generator equipped with an operating number selection device 17 that determines the number of ozone generators and sends an output signal to the ozone generator controllers 14a, 14b, . . . 14n.

In FIG. 1, the multiplier 3 calculates F'×C' using the output signal Fa of the adder 16 that totals the flowmeters 2a, 2b, . . . 2n and the output signal C' of the ozone concentration meter 1. On the other hand, the flow meter 6 for treated water and the ratio setting device 7 give the output signal f of the ratio controller 8 to the operating number selection device 17 and at the same time to the ozone generation amount controller 13. Ozone generator 11a, 11
b...11n ozone generator controller 14a, 14
b...14n is the signal 17 of the operating number selection device 17
In response to the output signal 13a of the ozone generation amount controller 13, the ozone generator is controlled as necessary.

The output signals of the flowmeters 2a, 2b...2n provided at the outlet of the ozone generator 11, which can all be adjusted, are summed up by an adder 16, and the output signal F' is multiplied by the output signal of the ozone concentration meter 1. C′×
F' is calculated and the resulting signal Yo' is given to the ozone generation amount controller 13. Ozone generation amount controller 1
3 is an output signal f of a ratio controller 8 that receives a signal from a flowmeter 6 that measures the amount of water flowing into the ozone treatment tank 9
A comparison operation is performed using the set value and the signal Yo' as the feedback value, and an increase/decrease signal such that the difference becomes zero is sent to the ozone generator controllers 14a, 14b...14
n, and the controller uses this signal to increase or decrease the voltage or frequency applied to the ozone generator or the voltage and frequency.

On the other hand, the operating number selection device 17 that receives the output signal f of the ratio controller 8 divides the output signal f, that is, the required ozone amount, by the preset minimum load amount per ozone generator, and selects the number of ozone generators. The number of units in operation is calculated, and an operation or stop command is issued to the ozone generator controller 14 in a preset order. The ozone generator controller 14 receives the command and controls the operation or stop of the corresponding ozone generator, and also receives the output signal of the ozone generation amount controller 13 during operation,
Controls the voltage or frequency or voltage and frequency applied to the corresponding ozone generator.

When the calculation result of the operating number selection device 17 is greater than the number n of ozone generators installed, naturally the number of operating units is n and the amount of ozone generated is automatically increased by the controller 13 by adjusting the load of each ozone generator. It will be covered by this. In addition, the operating number selection device 17
If the calculation result in is one or less, a correction is made to keep the number of operating vehicles at one.

On the other hand, the air compressor selection device 15 receives the required ozone generation amount output signal f from the ratio controller 8, and calculates f/C ₀ at a preset standard ozone concentration C ₀ to obtain a standard air amount Q. Standard air volume is calculated by dividing ₀ by the preset maximum air volume, i.e. 100% air volume.
Calculate the ratio of Q ₀ and if the ratio is less than 25%
25% air compressor 4a, 4b, ratio is 25% or more 50
If the ratio is less than 50%, use 50% air compressor 4c, 4d; if the ratio is 50% or more and less than 75%, use 50% air compressor 4.
c, 4d and 25% air compressor 4a,
If the ratio of either of 4b is 75% or more,
Issue a signal to operate each of the two 50% air compressors. Based on this operation signal, the air compressor can generate air amounts of 25%, 50%, 75%, and 100% of the maximum air amount in stages, and supply them to the ozone generator via the air drying device 12.

In this way, with the conventional ozone generator system that combines multiple ozone generators and multiple air compressors, the required amount of ozone is correctly controlled and ozone is injected at a predetermined ratio to the flow rate of the material to be treated. However, the ozone concentration in the injected ozone gas is not constant and varies greatly because the discharge amount of the air compressor is not continuously controlled. In other words, the ozone gas amount f′ and the ozone concentration
Although the product of C', that is, the amount of ozone, is correctly controlled to be constant, the ozone gas amount f' changes stepwise, so the ozone concentration C' changes in a sawtooth pattern. Figure 2 shows this situation. For example, when ozone is used to sterilize water, it is not effective unless the ozone concentration in the water to be treated is 0.4mg/or higher, so based on the principle of gas-liquid equilibrium, the ozone concentration in the ozone gas injected must be higher than a predetermined value. Must be.
Furthermore, the higher the ozone concentration in ozone gas, the higher the absorption efficiency of ozone into water.On the other hand, the total power efficiency of the ozone generator and air source is closely related to the ozone concentration, as shown in Figure 3. 16 to 20
The maximum efficiency is obtained at an ozone concentration of g/Nm ³ . In FIG. 3, 21 shows the total power, 22 shows the discharge power, and 23 shows the air source power.

Therefore, there has been a desire for a system that can maintain a constant ozone concentration in a conventional system combining multiple ozone generators and multiple air compressors to improve the efficiency of the entire system.

[Purpose of the invention]

The present invention aims to improve the drawbacks of the conventional ozone generator equipped with a plurality of air compressors as described above, and provides an ozone generator in which ozone concentration is controlled to be constant. .

[Summary of the invention]

The present invention includes a flowmeter that measures the flow rate of a processed material;
A ratio controller outputs the required amount of ozone generation based on the output signal of this flowmeter and the output signal from a preset ratio setting device, and the required number of units to be operated is selected based on the output signal of this ratio controller. A device for selecting the number of operating units, an ozone generator, an ozone gas flowmeter that measures the flow rate of ozone generated from this ozone generator, and an ozone gas flowmeter that is connected in series to the ozone gas flowmeter and the ozone generator to measure the concentration of the ozone generated. an adder that adds the output signals of the ozone gas flowmeter, a multiplier that multiplies the output signal of the adder and the output signal of the ozone concentration meter, and the output signal of the multiplier and An ozone generation amount controller that adjusts the amount of ozone generation based on the output signal of the ratio controller, and an ozone generation device that controls the ozone generator based on the output signal of the ozone generation amount controller and the output signal of the operating number selection device. An ozone generator consists of a machine controller, an air dryer that sends dry air to the ozone generator, and multiple air compressors connected in parallel to supply air to the air dryer. , a division calculator that divides the output signal of the ratio controller by a preset standard ozone concentration, and air compression by dividing the standard air volume signal, which is the output of this division calculator, by a preset maximum air volume. an air compressor selection device that selects the compressor, and an air volume controller that outputs a rotation speed control signal so that the deviation between the output signal summed by the adder and the standard air volume signal output from the division calculator becomes zero. and a rotation speed control device that controls the rotation speed of an electric motor for an air compressor based on a rotation speed control signal from the air volume controller and a selection signal from the air compressor selection device. . That is, a division calculator that divides the output signal of the ratio controller by a preset coefficient, an air compressor selection device that selects an air compressor based on the output signal of the division calculator, and a % capacity air compressor 2
In an ozone generator equipped with one air compressor and two air compressors with a capacity of 50% of the required maximum air volume, the rotation speed control device that controls the rotation speed of the air compressor and the output signal of the ozone gas flow meter are used as feedback values, and the division calculation is performed. This ozone generator is equipped with an air volume controller that sends an output signal to an air compressor rotation speed control device using the output signal of the air compressor as a set value.

[Embodiments of the invention]

Next, examples of the present invention will be described. FIG. 4 shows a flowmeter 6 that measures the flow rate of the material to be treated, and a ratio that outputs the required ozone generation amount f based on the output signal 6a of the flowmeter 6 and the output signal 7a from a preset ratio setting device 7. A controller 8, an operating number selection device 17 that selects the required number of operating units based on the output signal of the ratio controller 8, and ozone generators 11a, 11b...
11n, ozone generators 11a, 11b...11
ozone gas flowmeters 2a, 2b...2n that measure the flow rate of ozone generated from ozone gas flowmeters 2a, 2b...2n and an ozone generator 11a,
ozone concentration meter 1 connected in series to 11b...11n to measure the concentration of ozone generated; a totalizer 16 that adds the output signals of ozone gas flowmeters 2a, 2b...2n; and totalizer 16.
A multiplication calculator 3 multiplies the output signal of and the output signal C' of the ozone concentration meter 1, and the amount of ozone generation is adjusted by the output signal Yc' of the multiplication calculator 3 and the output signal f of the ratio controller 8. Ozone generation amount controller 13
and ozone generator controllers 14a, 14b...14 that control the ozone generators 11a, 11a...11n by the output signal 13a of the ozone generation amount controller 13 and the output signal 17a of the operating number selection device 17.
n, an air drying device 12 that sends dry air to the ozone generators 11a, 11b...11n, and a plurality of air compressors 4a, 4b... connected in parallel that supply air to the air drying device 12. ...4d, a division calculator 20 that divides the output signal of the ratio controller 8 by a preset standard ozone concentration, and a standard air amount signal 20a that is the output of the division calculator 20. an air compressor selection device 15 that selects an air compressor by dividing the amount by a preset maximum air amount; and a totalizer 16.
an air volume controller 21 that outputs a rotational speed control signal 21a so that the deviation between the output signal summed by and the standard air volume signal output from the division calculator 3 becomes zero;
and the rotation speed control signal 21a from the air volume controller 21.
and a selection signal 15 from the air compressor selection device 15
Electric motors 18a, 18b for air compressors by a
...Rotation speed control device 1 that controls the rotation speed of 18d
9a, 19b...19d is shown.

In Figure 4, the air compressor accounts for 25% of the total air volume.
Two 50% capacity air compressors (4a, 4b) and two 50% capacity air compressors (4c, 4d), and AC motors 18a, 18b that drive the respective air compressors.
18c, 18d, and rotational speed control devices 19a, 19 that change and control the rotational speed of these AC motors.
b, 19c, 19d and an ozone generation amount output signal f from the ratio controller 8, and a division calculator 20 that calculates f/C ₀ at a preset standard ozone concentration C ₀ ;
The output of the division calculator 20, that is, the standard air amount Q ₀ , is divided by the preset maximum air amount, that is, 100% air amount, and then divided by the standard air amount to calculate the ratio of the standard air amount Q ₀ . An air compressor selection device 15 that selects an air compressor to be operated based on the selected air compressor and outputs an operation command is connected to each of a plurality of ozone generators 11a, 11b...11n connected in parallel to generate ozone. ozone gas flowmeters 2a, 2b...2n that measure the flow rate of ozone gas, a totalizer 16 that totals the output signals of these ozone gas flowmeters, and an output signal of the totalizer 16 using the output _Q0 of the division calculator 20 as a set value. It consists of an air volume controller 21 that controls the rotation of the rotation speed control device 18 so that F' is a feedback value and the deviation thereof becomes zero.

The ratio controller 8 receives the output signal 6a of the flow meter 6 for the amount of liquid to be treated, and in response to the signal 7a from the ratio setting device 7, the ratio controller 8 gives the output signal f to the operating number selection device 17 of the ozone generators to operate the ozone generators. At the same time as issuing the command, it is also given to the ozone generation amount controller 13 to control the ozone generator, and the output signal f of the ratio controller is further given to the division calculator 20 and set in advance in the division calculator. Calculate f/C ₀ with standard ozone concentration C ₀ and output standard air amount Q ₀ as a result. This output Q ₀ is given to the air compressor selection device 15 to calculate Q ₀ /Qmax×100=γ% using a preset maximum air amount Qmax. Based on this calculation result, the air compressor selection device 15 selects the air compressor as follows. In other words, when γ% is less than 25%, 25% of the total air volume
A signal is issued to command the rotation speed control of the AC motor that is correlated with the operation of either the capacity air compressor 4a or 4b, and when γ% is 25% or more and less than 50%, the signal is 50%.
% capacity air compressor 4c or 4d and to control the rotation speed of the electric motor. When γ% is 50% or more and less than 75%, the 50% capacity air compressor 4c or 4d is activated. Either one and 25%
A signal is issued to command the operation of one of the air compressors 4a and 4b with a capacity of 50% and the rotation speed control of the motor of the air compressor with a capacity of 50%, and when γ% is 75% or more,
A signal is issued to operate two 50% capacity air compressors and control the rotation speed of one of the motors.

Now, to explain the reason why the air compressor is operated and controlled as described above, the air compressor for the ozone generator usually has a discharge pressure of 1 kg/cm ² G.
A rotary vane type compressor is usually used because it is sufficient. Typical examples include Roots type and rotary type air compressors. Therefore, since the rotation speed of the rotor blade is proportional to the discharge air volume, the discharge air volume can be easily controlled by controlling the rotation speed of the electric motor, but at a rotation speed of less than 1/2 of the rated rotation speed, Since it is difficult to maintain the discharge pressure, the air volume is controlled by reducing the rotation speed to 1/2 of the rated value.
It's been a long time since I've been in the middle of a long time.

In addition, in the air compressor selection control described above, γ%
When is 25% or more and less than 50%, two 25% capacity units may be operated and the rotation speed may be controlled at the same time. Of course, the selection of one of the air compressors of the same capacity must be input in advance.

Now, the air compressor selected by the command from the air compressor selection device is operated, and as a result, the amount of air discharged is controlled by the ozone generators 11a, 11b...11n installed in parallel via the air drying device 12. Among them, the ozone generator is supplied only to the ozone generators that are instructed to operate by the operation number selection device 17. Flow meters 2a, 2b...2n installed in series at the ozone generator outlet
The output signals of are summed by the totalizer 16 and the output signal F' is sent to the air volume controller 21. Air volume controller 21
uses the standard air amount Q ₀ outputted by the division calculator 20 as a set value, uses the output signal F' of the totalizer 16 as a feedback value, and outputs a rotational speed control signal 21a so that the deviation thereof becomes zero.

On the other hand, the rotation speed control device instructed to control the rotation speed by the air compressor selection device 15 is the air volume controller 21.
The rotational speed of the electric motor of a predetermined air compressor is controlled by the output signal 21a.

In FIG. 4, the output signal of the ratio controller 8 is divided by f, and the calculation unit 20 calculates f/C ₀ , and as a result, the standard air amount Q ₀ is output, which is set in advance by the air compressor selection device 15. Maximum air volume
It was explained that Qmax calculates Q ₀ /Qmax×100=γ%, but since _C0 and Qmax are both coefficients set in advance, 1/ _C0 ×1/Qmax×100=γ% proportionality. Since it is possible to obtain fK=γ%, where K is the coefficient, the calculation of fK=γ% can be performed by the air compressor selection device 15, abbreviated as a division arithmetic unit.

Also, multiple ozone generators 11a, 11b...
If there is only one 11n, flowmeters 2a, 2b...
Of course, since there is only one totalizer 2n, the totalizer 16 is naturally unnecessary. Also, a flow meter 2 that measures the discharge air volume of multiple ozone generators in series.
a, 2b...2n are necessary to check each flow rate because the power efficiency of ozone generation is better if the amount of air passing through each ozone generator is uniform, but if you ignore the power efficiency, Flowmeter 2a, 2
Instead of b...2n, one flow meter may be installed after collecting the discharge air volume of each ozone generator, and the totalizer 16 is not necessary in this case as well.

〔Effect of the invention〕

According to the present invention, in an ozone generator comprising an ozone generator and a plurality of air compressors, there is an effect that the ozone concentration in ozone gas can be controlled to be constant, which was a drawback of the conventional ozone generator.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a conventional ozone generator, Figure 2
Figure 3 is an explanatory diagram showing changes in ozone concentration, Figure 3 is an explanatory diagram showing the relationship between ozone concentration and power consumption, and Figure 4 is an explanatory diagram showing the relationship between ozone concentration and power consumption.
The figure is a configuration diagram showing an embodiment of the ozone generator of the present invention. 1... Ozone concentration meter, 2a, 2b... 2n... Ozone gas flow meter, 3... Multiplier, 4a, 4b
...25% capacity air compressor, 4c, 4d...50% capacity air compressor, 6...flow meter, 7...ratio setting device, 8...ratio controller, 12...air drying device,
13... Ozone generation amount controller, 14a, 14b...
14n...Ozone generator control device, 15...Air compressor selection device, 16...Totalizer, 17...
... Ozone generator operation number selection device, 18a, 18
b...18d...Electric motor, 19a, 19b...19d
...Rotation speed control device, 20...Division calculator, 21
...Air volume controller.

Claims (1)

[Claims] 1. A flow meter that measures the flow rate of the material to be treated, a ratio controller that outputs the required amount of ozone generation based on the output signal of this flow meter and the output signal from a preset ratio setting device, and this ratio controller. an ozone generator, an ozone gas flowmeter that measures the flow rate of ozone generated from the ozone generator, and an ozone gas flowmeter and the ozone generator. an ozone concentration meter that is connected in series to the machine to measure the concentration of ozone generated; an adder that adds the output signals of the ozone gas flow meter; and an output signal of the adder and the output signal of the ozone concentration meter. a multiplication unit that performs a multiplication operation; an ozone generation amount controller that adjusts the amount of ozone generation based on the output signal of the multiplication unit and the output signal of the ratio controller; and the output signal of the ozone generation amount controller and the an ozone generator controller that controls the ozone generator according to an output signal of the operating number selection device; an air dryer that sends dry air to the ozone generator; and an air dryer that supplies air to the air dryer. In an ozone generator consisting of a plurality of air compressors connected in parallel, there is provided a division calculator for dividing the output signal of the ratio controller by a preset standard ozone concentration; an air compressor selection device that selects an air compressor by dividing an output standard air amount signal by a preset maximum air amount, and an output signal summed by the adder and an output signal output from the division calculator. an air volume controller that outputs a rotation speed control signal so that the deviation of the standard air volume signal becomes zero;
and a rotation speed control device that controls the rotation speed of the electric motor for the air compressor based on the rotation speed control signal from the air volume controller and the selection signal from the air compressor selection device.