JP4733848B2 - Ozone concentration half-life measuring device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention measures the half-life when ozone is attenuated by being consumed by reaction with pollutants when ozone is supplied into a container contaminated with pollutants such as various odor components and bacteria. The present invention relates to a device for measuring the half-life of ozone concentration.
[0002]
[Prior art]
Conventionally, when a room is contaminated with odor components or bacteria that have been volatilized from cigarettes, spoiled foods, various organic solvents, etc., ozone from the ozone generator is introduced into this contaminated space and the excellent oxidizing power of ozone. It is known that the contaminated space can be purified by decomposing odor components and bacteria.
[0003]
[Problems to be solved by the invention]
In order to clean the contaminated space by introducing ozone, it is necessary to know the degree of contamination in the contaminated space, and for this purpose, the concentration of contaminants in the contaminated space is detected. There are many types, and it is very difficult to detect the concentration of all pollutants.
[0004]
And even if it takes a lot of time and effort to detect the concentration of all pollutants, the problem is that the overall level of contamination cannot actually be evaluated substantially. While ozone reacts with various pollutants due to its strong oxidizing action, it is conceivable to use this property of ozone for comprehensive assessment of pollution.
[0005]
Therefore, it is conceivable to fill the inside of the contaminated space with a predetermined concentration of ozone and measure the time until the ozone concentration becomes 1/2 of the initial concentration, that is, the half-life of the ozone concentration. In other words, since this half-life comprehensively covers all the pollution situations in the pollution space, COD (chemical oxygen demand) and BOD (biological oxygen demand), which are indicators of water pollution status. It is thought that it becomes the optimum index of the degree of contamination of the contaminated space in the same way as in (Quantity).
[0006]
However, if the half-life of the ozone concentration is to be measured, once the contamination space is set to a predetermined ozone concentration, the ozone concentration is continuously attenuated over time until it becomes half the initial value. It has a problem that it is very troublesome.
[0007]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an ozone concentration half-life measuring apparatus that can easily measure the half-life of the ozone concentration.
[0008]
[Means for Solving the Problems]
  1st invention of this applicationIs an ozone concentration half-life measuring device that measures the half-life, which is a half decay time of ozone, by detecting changes in the supplied ozone concentration, and contains the gas or liquid to be measured.RucontainerAnd the containerAn ozone generator for supplying ozone therein, an ozone concentration detector for detecting the ozone concentration in the container, and a controller for calculating the half-life of the ozone concentration;An input / output device for inputting a command signal for sampling to the control device and outputting a calculation result of the control device,The control deviceAfter the start of measurement, when the command signal is input, the ozone concentration detector is configured to output a control signal to measure the ozone concentration, and the command signal is input from the start of measurement. A timer that measures the elapsed time t until the start of the measurementInitial ozone concentration in the container detected by the ozone concentration detector x₀WhenA half-life calculation unit that calculates the half-life of the ozone concentration based on the ozone concentration detected by the ozone concentration detector when the command signal is input, the elapsed time t measured by the timer, and the following ozone concentration attenuation formula: HaveIs.
  x = x ₀ × exp (−0.693t / τ)
Where t: elapsed time (hr), x: ozone concentration after elapse of t time (g / m ³ ), X ₀ : Initial concentration of ozone (g / m ³ ), Τ: half-life of ozone concentration (hr).
[0009]
  A second invention of the present application is an ozone concentration half-life measuring device for measuring a half-life, which is a half decay time of ozone, by detecting a change in the supplied ozone concentration. An ozone generator for supplying ozone into a container containing a liquid; an ozone concentration detector for detecting the ozone concentration in the container; a controller for calculating the half-life of the ozone concentration;
  An input / output device that inputs a command signal for sampling to the control device and outputs a calculation result of the control device, and the control device receives the command signal after driving of the ozone generator is started. A timer for measuring the time from the start of driving to the input of the command signal, and a configuration for outputting a control signal to the ozone concentration detector at the time when the ozone signal is measured. The amount of ozone Z injected into the container per unit time by the ozone generator, the volume V of the container, the initial ozone concentration in the container detected by the ozone concentration detector at the start of measurement, and the input of the command signal Half-life calculation that calculates the half-life of the ozone concentration based on the ozone concentration detected by the ozone concentration detector, the time measured by the above timer, and the following ozone concentration increase formula With the doorA half-life measuring device characterized by that.
  x = (Z / V) × (τ / −0.693) × (1-exp (−0.693 t / τ))
However, Z: ozone injection amount per unit time (g / hr), V: capacity of container (m ³ ), T: elapsed time (hr), x: ozone concentration after elapse of t time (g / m ³ ), Τ: half-life of ozone concentration (hr).
[0010]
  theseAccording to the invention,Compared to the half-life measurement method in which ozone concentration must be measured continuously and continuously with an ozone concentration detector until the ozone reaches a saturated concentration, the measurement time is significantly shortened. Is greatly improved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an explanatory view showing an embodiment of an ozone concentration half-life measuring apparatus 100 according to the present invention, and FIG. 2 is a perspective view showing an embodiment of the external shape of the half-life measuring apparatus shown in FIG. It is. The half-life measuring apparatus 100 supplies ozone having a predetermined concentration to sample air collected from the contaminated space to be measured for the half-life of the ozone concentration, and appropriately detects the ozone concentration of the sample air, and based on the detection result. And calculates the half-life of the ozone concentration.
[0012]
As shown in FIG. 1, the half-life measuring apparatus 100 has a basic configuration including a measuring apparatus main body 10 and a sampling box (container) 50 provided adjacent to the measuring apparatus main body 10. The half-life measuring device 100 is formed by mounting the measuring device main body 10 and the sampling box 50 in a box-shaped casing 101 as shown in FIG.
[0013]
Such a half-life measuring device 100 is brought into a contaminated space to be measured, and in this contaminated space, contaminated air is taken into the sampling box 50 as sample air, and the partition member support structure 50 is hermetically sealed. Then, ozone is supplied to the sample air to calculate the half-life of the ozone concentration and output the calculation result.
[0014]
Thus, the sampling box 50 includes a wall portion 51 that surrounds the five sides, and an openable opening / closing door 52 provided on the right side of the casing 101 that is the other side in FIGS. 1 and 2. ing. A sampling space 53 for taking in contaminated air is formed by a space surrounded by the wall portion 51 and the opening / closing door 52.
[0015]
In addition, a rectangular contaminated air intake 102 is opened on the right side of the casing 101, and the open / close door 52 rotates around a horizontal shaft 103 that is installed so as to cross the upper portion of the contaminated air intake 102. It is supported freely. Accordingly, the contaminated air in the measurement target space is taken into the sampling space 53 by bringing the half-life measuring device 100 into the measurement target space and then reciprocating the opening / closing door 52 around the horizontal axis 103 a plurality of times. It will be.
[0016]
Further, a stirring fan 54 is provided at an appropriate position of the wall 51 of the partition member support structure 50 (in the example shown in FIG. 2, the bottom of the sampling space 53), and the stirring of the air in the sampling space 53 by driving the stirring fan 54 is performed. Thus, the odor component from the measurement target contaminated space is uniformly diffused, and the ozone introduced from the measurement apparatus main body 10 is also diffused uniformly.
[0017]
As shown in FIG. 1, the measuring apparatus main body 10 that measures the half-life of the ozone concentration in the sampling space 53 generates an ozone generator 20 that supplies ozone into the sampling space 53, and the sampling space 53. The ozone concentration detector 30 for detecting the ozone concentration in the inside, and calculating the half-life of the ozone concentration in the sampling space 53 based on the detection signal from the ozone concentration detector 30 and various controls for this measurement It has the basic composition provided with control device 40 which performs.
[0018]
The ozone generator 20 generates a discharge by applying an AC high-frequency high voltage from the AC high-voltage generation circuit 21 and an AC high-voltage generation circuit 21 that generates commercial power and generates an AC high-frequency high voltage. A counter electrode 22 and a fan 23 for sending air between the counter electrodes 22 are provided. A part of oxygen in the air supplied between the counter electrodes 22 by the drive of the fan 23 is converted into ozone by the action of discharge, and this ozone is supplied to an ozone supply line 24 provided at the downstream end of the ozone generator 20. And is introduced into the sampling space 53.
[0019]
The ozone concentration detector 30 is a commercially available product configured to supply sample air in the sampling space 53 sucked through the sample pipe 31 to a predetermined ozone sensor such as an ultraviolet absorption method or a semiconductor sensing method. The thing is adopted. The ozone concentration detection signal detected by the ozone sensor is inputted to the control device 40 one by one.
[0020]
In the present embodiment, the ozone generator 20 using the discharge generated by applying an AC high frequency high voltage to the counter electrode 22 is used as a device for generating ozone. However, the present invention generates ozone. The apparatus is not limited to the ozone generator 20 as described above, and an ultraviolet lamp capable of irradiating ultraviolet rays having a wavelength near 170 nm may be adopted.
[0021]
The control device 40 is a small computer called a so-called microcomputer, and is equipped with a CPU (Central Processing Unit) and a storage device, and has an input keyboard, an output display and a printer. The input / output device 41, the RAM 42 which is a readable / writable external storage device, and the ROM 43 which is a read-only external storage device are packaged.
[0022]
From the input / output device 41, various measurement conditions, operating conditions of the ozone generator 20, and the like are input, the detection result by the ozone concentration detector 30, and the ozone concentration in the sampling space 53 calculated by the control device 40. The half-life of is output.
[0023]
The RAM 42 is used to temporarily store data that can be updated, such as input data from the input / output device 41, intermediate data being calculated in the control device 40, and the like.
[0024]
The ROM 43 stores a program for calculating the half-life of the ozone concentration and a program for controlling the operation of the ozone generator 20 and the ozone concentration detector 30. Accordingly, by turning on a start switch (not shown) provided in the input / output device 41, each program is read into the control device 40, whereby the control device 40 can perform control based on each program. It becomes a state.
[0025]
The control device 40 includes a half-life calculation unit 44 configured by combining an internal CPU and a storage device. The half-life calculation unit 44 is based on a detection signal from the ozone concentration detector 30. Therefore, the half-life of the ozone concentration is to be calculated. This calculation result is output via the input / output device 41.
[0026]
The input / output device 41 has an interface part for exchanging with an operator provided in the input / output space 104 on the left side of the casing 101 in FIG. The input / output space 104 is formed by recessing a part of the outer plate and the top plate of the casing 101, and includes a panel plate 105 on the side plate side and a display plate 106 on the top plate 107 side.
[0027]
The panel board 105 is provided with a numeric keypad and other operation keys, a power switch, and the like, and the display board 106 is provided with a display screen 46 including, for example, a liquid crystal. An input result via the operation key, a calculation result by the control device 40, and the like are displayed on the display.
[0028]
Further, an output port 108 which is an elongated opening for feeding out the output paper 47 of a printer (not shown) is provided at an appropriate position of the top plate 107, and the calculation result of the control device 40 is output from the output port 108. The paper 47 is printed out.
[0029]
Hereinafter, a calculation method of a program stored in the ROM 43 and called up whenever necessary and the half-life calculation unit 44 calculates the half-life of the ozone concentration will be described. The capacity of the sampling space 53 is represented by V (m^Three) And ozone of Z (g / h) is injected through the ozone supply line 24. And
x: ozone concentration in the sampling space 53 (g / m^Three)
t: Time elapsed from the start of ozone injection (h)
γ: Decay rate of ozone concentration
The amount of change in ozone concentration (dx) over the course of a minute time (dt) is
dx = (Z / V) · dt−γx · dt (1)
It becomes.
[0030]
Solving this equation (1)
x = ∫ ((Z / V) −γx) dt
= (Z / V) · (1 / γ) · (1-e^{- γ t})… ▲ 2 ▼
It becomes.
[0031]
And since there exists a relationship of “γ = −0.693 / τ” between the attenuation rate (γ) and the half-life (τ), by substituting this relationship into the equation (2),
x = (Z / V) · (τ / −0.693) · (1-e^{-(-0.693 / τ ) ・ t})… ▲ 3 ▼
It becomes.
[0032]
Since the expression (3) derived in this way is a constant in which the values of (Z) and (V) are preset, the ozone concentration (x) in the sampling space 53 is the half-life of the ozone concentration ( It is a function of τ) and elapsed time (t). Then, if “t → ∞” is set, “(1-e^{-(-0.693 / τ ) ・ t}) → 1 ”
x_∞= (Z / V) · (τ / -0.693) ... (4)
In the sampling space 53, the ozone saturation concentration (x) in a state where the ozone supplied from the ozone supply line 24 and the consumption of the ozone consumed by the pollutants in the sample air are balanced._∞) And half-life (τ).
[0033]
Therefore, the equation (4) is stored in advance in the ROM 43 of the measuring apparatus main body 10, and the detection signal of the ozone concentration detector 30 is sent when the ozone concentration in the sampling space 53 reaches the saturated concentration. The half-life calculation unit 44 may be input to cause the half-life calculation unit 44 to calculate the half-life (τ) value according to the equation (4). Is the saturation concentration (x_∞) Takes a long time (usually 3 to 5 hours).
[0034]
Therefore, in the present embodiment, the half-life of the ozone concentration is calculated based on the ozone concentration in the sampling space 53 when an arbitrary time has elapsed since the start of ozone injection into the sampling space 53. For this purpose, an arithmetic expression obtained by modifying the above expression (3) is adopted. That is, in the formula (3), “(Z / V) · (1 / −0.693)” is a constant, so this is set as “c”. Then, the above equation (3) is expressed as “x = cτ · (1-e^{-0.693t / τ}) ”. In this equation, the elapsed time t₀The ozone concentration at time x is x₀Is "x₀= Cτ · (1-e^{-0.693t0 / τ}) ", And by transforming this expression," 1- (x₀/ Cτ) = e^{-0.693t0 / τ}Is obtained.
[0035]
In this formula, for convenience of calculation, “C = x₀/ C "," T = -0.693t₀”And“ τ_x= 1 / τ ”and the expression is transformed,“ ln (1-C · τ) = − T · τ_x" If the left side of this expression is expanded according to the regular method,
ln (1-C · τ_x) =-C · τ_x+ C²・ Τ_x ²/ 2-C^Three・ Τ_x ^Three/3...▲5▼
The expansion formula is obtained. By ignoring the third and subsequent terms on the right side of equation (5) and adopting up to the second term, “−T · τ_x= -C ・ τ_x+ C²・ Τ_x ²/ 2 "is obtained. Based on this formula τ_x, And undoing and rearranging each replacement of the above formula for convenience,
τ = {x₀/[(Z/V)·(1/−0.693)]²} / 2 {x₀/[(Z/V)·(1/−0.693)]−0.693t₀}… ▲ 6 ▼
Can be obtained. In equation (6), x₀, Z, V and t₀Are all known values, the values of the ozone concentration half-life (τ) can be obtained by substituting these values into the equation (6) for calculation.
[0036]
In the present invention, the above formula (6) is stored in the ROM 43 in advance, and the formula (6) is called from the ROM 43 to the half-life calculation unit 44 whenever necessary, and the half-life based on the formula (6) is here. The operation is executed.
[0037]
Specifically, after ozone is injected into the sampling space 53 from the ozone generator 20, a command signal for sampling is input to the control device 40 via the input / output device 41 after an arbitrary time has elapsed. Then, the control device 40 outputs a control signal to the ozone concentration detector 30, whereby the ozone concentration detector 30 sucks the sample gas from the sampling space 53 through the sample pipe line 31, and predetermined ozone The sensor detects the ozone concentration and outputs this detection signal to the half-life calculation unit 44.
[0038]
The half-life calculator 44 that has received this detection signal calculates the half-life of the ozone concentration based on the above equation (6). Incidentally, a timer 45 is built in the half-life calculation unit 44, and this timer is turned on when the driving of the ozone generator 20 is started, and the command signal from the input / output device 41 is inputted to the control device 40. At this point, the timer is turned off, so that the elapsed time from the start of driving the ozone generator 20 to the sampling by the ozone concentration detector 30 (t in equation (6))₀) Is measured. The calculation result of the half-life (τ) by the half-life calculation unit 44 is output to the input / output device 41. The input / output device 41 displays the calculation result on the screen and prints it out from the printer as necessary. The half-life (τ) of the ozone concentration in the sampling space 53 to be measured can be known from this output value.
[0039]
As described above, according to the method for obtaining the half-life of the ozone concentration using the equation (6), the ozone from the ozone generator 20 starts to be injected into the sampling space 53, and then the ozone is passed after an arbitrary time has passed. By detecting only one point of the ozone concentration in the sampling space 53 by the concentration detector 30, the half-life (τ) of the ozone concentration can be obtained immediately, so that the ozone concentration in the sampling space 53 is changed over time until it reaches saturation. The measurement time can be greatly shortened compared to the half-life measurement method in which the measurement is continuously performed and the measurement result is graphed and the half-life is obtained.
[0040]
Next, a method for obtaining the half-life based on an arithmetic expression different from the expression (6) will be described. In this method, contrary to the previous embodiment, the ozone concentration in the sampling space 53 is the initial value (x₀) Is applied when it is set as).
[0041]
In this case, a differential equation is created assuming that ozone of a predetermined concentration already exists in the sampling space 53 at the start of measurement, and that ozone is consumed by a contaminant in the sample air at a predetermined attenuation rate. By solving the equation
x = x₀・ E^{-0.693t / τ}… ▲ 7 ▼
The ozone concentration attenuation formula can be obtained. In the formula (7), τ is the half-life (h) of the ozone concentration, t is the elapsed time (h) from the start of measurement, x₀Is the initial ozone concentration in the sampling space 53, x is the ozone concentration at the elapsed time t (g / m^Three).
[0042]
For obtaining the half-life (τ) by modifying the above formula (7)
τ = (− 0.693t) / ln (x / x₀) ... ▲ 8 ▼
Can be obtained. This equation (8) is the concentration of ozone in the sampling space 53 x₀Is measured by the ozone concentration detector 30 and the ozone concentration in the sampling space 53 is again measured by the ozone concentration detector 30 when t time has elapsed from the measurement of the initial concentration. It shows that the concentration half-life is calculated immediately.
[0043]
In this embodiment, instead of the above equation (6), equation (8) is stored in the ROM 43, and each time measurement is performed, the equation (8) is read into the half-life calculation unit 44 and half-life calculation is executed. Will be.
[0044]
As described above in detail, the measurement apparatus main body 10 of the present invention measures the half-life (τ) of the initial concentration of ozone by detecting a change in the concentration of ozone supplied in the predetermined sampling space 53. The ozone generator 20 that supplies ozone into the sampling space 53, the ozone concentration detector 30 that detects the ozone concentration in the sampling space 53, and the half-life (τ) of the ozone concentration The control device 40 has a half-life calculation unit 44, and the half-life calculation unit 44 has a sampling space 53 detected by the ozone concentration detector 40. Is configured to calculate the ozone concentration half-life (τ) based on the initial ozone concentration and the ozone concentration after an arbitrary period of time. When determining, the ozone concentration half-life (τ) of the sampling space 53 can be obtained only by measuring the initial ozone concentration in the sampling space 53 and the ozone concentration at an arbitrary time point, and the ozone is saturated. Compared with the half-life measurement method in which the inside of the sampling space 53 must be measured with time and continuously with the ozone concentration detector 30 until the concentration is reached, the measurement time is remarkably shortened, and thereby the ozone concentration half-life (τ) The measurement efficiency can be greatly improved.
[0045]
As a calculation formula for calculating the ozone concentration half-life (τ), x = x₀Xexp (−0.693t / τ) (the above formula (7)) is adopted, and this calculation formula is stored in the control device 40, and the half-life calculation unit 44 stores the ozone concentration half-life (τ) based on this calculation formula. ) Can be calculated. When this calculation formula is adopted, the initial ozone concentration (x₀) And the ozone concentration (x) in the sampling space 53 at the elapsed time (t) are measured by the ozone concentration detector 30 to obtain the ozone concentration half-life (τ). .
[0046]
Further, instead of the above formula, x = (Z / V) × (τ / −0.693) × (1-exp (−0.693 t / τ)) (the above formula (3)) is adopted. Also good. When this equation is adopted, the initial ozone concentration in the sampling space 53 is “0 g / m 2.^ThreeSince it is known in advance, the ozone concentration half-life is obtained by measuring only one point of the ozone concentration in the sampling space 53 at an arbitrary elapsed time (t) after the supply of ozone to the sampling space 53 is started. (Τ) can be obtained.
[0047]
In the above embodiment, air as a gas has been described as an example of the contamination target. However, the present invention is not limited to the contamination target being a gas, and the contamination target is water or the like. It may be a liquid.
[0048]
【Example】
When the measurement apparatus main body 10 according to the present invention measures the ozone concentration half-life (τ) in the sampling space 53 in which a predetermined pollutant exists, the measurement device main body 10 in the sampling space 53 is based on the half-life (τ) of the measurement result. In order to verify whether or not the change in ozone concentration with time coincides with the actual half-life, the following test was performed.
[0049]
First, 1m^ThreeA predetermined amount of a banana as a contamination source is loaded into a rectangular parallelepiped sealed sampling space (the surface of the wall 51 is covered with vinyl chloride) as shown in FIG. Was injected into the sampling space 53 through the ozone supply line 24. The injection amount of ozone was set to 0.7 mg / h.
[0050]
Then, while the ozone concentration detector 30 measures the ozone concentration in the sampling space 53 in a predetermined measurement span, the ozone is saturated (x_∞) Until ozone is reached and the saturation concentration (x_∞The ozone injection was stopped when it was deemed that the Measurement of the ozone concentration with the ozone concentration detector 30 was continued even after the ozone injection was stopped, and the measurement with the ozone concentration detector 30 was stopped when the ozone concentration became substantially “0”. These measured values were printed out by the input / output device 41.
[0051]
On the other hand, based on the ozone concentration (x) measured by the ozone concentration detector 30 when 1 hour has passed since the start of the measurement of the ozone concentration (t = 1), the ozone concentration is halved by the above equation (6). The period (τ) was determined, and the value of τ was substituted into the above equations (3) and (7), and the calculated ozone concentration over time was printed out from the input / output device 41.
[0052]
FIG. 3 is a graph showing the change over time of the ozone concentration in the sampling space 53 obtained by these printouts. The measured value is indicated by a broken line, and the calculated value is indicated by a black circle.
[0053]
As is apparent from the graph of FIG. 3, the calculated value of the ozone concentration corresponds well with the actually measured value, and from this, the half-life using the half-life measuring apparatus 100 of the present invention is It was proved that the measurement results were extremely accurate.
[0054]
【The invention's effect】
  According to the present invention,Initial ozone concentration in the containerOr the amount of ozone injected into the container per unit time by the ozone generator and the capacity of the container, the elapsed time from the start of measurement until the input / output device inputs a command signal to the control device, and the command signal Is detected by ozone concentration detectorThe ozone concentration half-life in the container can be obtained simply by measuring the ozone concentration, and the ozone concentration in the container must be measured over time and continuously with an ozone concentration detector until the ozone is saturated. Compared with the half-life measurement method that does not become necessary, the measurement time is remarkably shortened, and thereby the measurement efficiency of the ozone half-life can be greatly improved.
[0055]
Therefore, if the half-life of the ozone concentration measured by such a half-life measuring device is adopted as an evaluation index for the degree of contamination in the contaminated space, the concentration of the pollutant itself is measured, and the degree of contamination in the contaminated space is measured using the measured value. Compared with the conventional evaluation method for evaluating the ozone, it is possible to evaluate the degree of total contamination more quickly and appropriately, and the ozone injection plan for determining the ozone amount and ozone concentration to be injected is more effective. Can be a thing.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of an ozone concentration half-life measuring apparatus according to the present invention.
2 is a perspective view showing an embodiment of an external shape of the half-life measuring apparatus of FIG. 1. FIG.
FIG. 3 is a graph showing a change in ozone concentration with time, in which a measured value is indicated by a broken line, and a calculated value is indicated by a black circle.
[Explanation of symbols]
100 Half-life measuring device 101 Casing
102 Contaminated air inlet 103 Horizontal axis
104 Input / output space 105 Panel board
106 Display board 107 Top board
108 Output port
10 Measuring device body 20 Ozone generator
21 AC high voltage generation circuit 22 Counter electrode
23 Fan 24 Ozone supply line
30 Ozone concentration detector 31 Sample pipe
40 control device 41 input / output device
42 RAM 43 ROM
44 Half-life calculator 45 Timer
46 Display screen 47 Output paper
50 Sampling box (container)
51 Wall 52 Opening / closing door
53 Sampling space 54 Stirring fan

Claims (2)

An ozone concentration half-life measuring device that measures a half-life that is a half decay time of ozone by detecting a change in the supplied ozone concentration,
A container a gas or liquid to be measured is Ru is accommodated,
An ozone generator for supplying ozone into the container ;
An ozone concentration detector for detecting the ozone concentration in the container;
A control device for calculating the half-life of the ozone concentration ;
An input / output device that inputs a command signal for sampling to the control device and outputs a calculation result of the control device,
The control device
After the start of measurement, when the command signal is input, the ozone concentration detector is configured to output a control signal to measure the ozone concentration, and
A timer for measuring an elapsed time t from the start of measurement until the command signal is input;
The initial ozone concentration x ₀ in the container detected by the ozone concentration detector at the start of the measurement, the ozone concentration detected by the ozone concentration detector at the time of inputting the command signal, the elapsed time t measured by the timer, and the following ozone A half-life measuring device comprising a half-life calculating unit for calculating a half-life of ozone concentration based on a concentration decay equation .
x = x ₀ × exp (−0.693 t / τ)
However, t: elapsed time (hr), x: ozone concentration (g / m ³ ) after elapse of t time, x ₀ : initial ozone concentration (g / m ³ ), τ: half-life of ozone concentration (hr) . An ozone concentration half-life measuring device that measures a half-life that is a half decay time of ozone by detecting a change in the supplied ozone concentration,
An ozone generator for supplying ozone into a container containing a gas or liquid to be measured;
An ozone concentration detector for detecting the ozone concentration in the container;
A controller that calculates the half-life of the ozone concentration;
An input / output device that inputs a command signal for sampling to the control device and outputs a calculation result of the control device,
The control device
After the start of driving the ozone generator, the control signal is output to the ozone concentration detector at the time when the command signal is input, and the ozone concentration is measured.
A timer for measuring the time from the start of driving to the input of the command signal;
The amount Z of ozone injected into the container per unit time by the ozone generator, the volume V of the container, the initial ozone concentration in the container detected by the ozone concentration detector at the start of measurement, and the input of the command signal A half-life measurement characterized by having a half-life calculation unit for calculating the half-life of the ozone concentration based on the ozone concentration detected by the ozone concentration detector, the time measured by the timer, and the following ozone concentration increase formula apparatus.
x = (Z / V) × (τ / −0.693) × (1-exp (−0.693 t / τ))
However, Z: injection amount of ozone per unit time (g / hr), V: capacity of container (m ³ ), t: elapsed time (hr), x: ozone concentration after elapse of t time (g / m ³⁾ ), Τ: half-life of ozone concentration (hr).

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