CN201527398U - Gas supply device - Google Patents

Abstract

The utility model discloses a gas supply device comprising a light source, a light filtering module, a conversion unit and a measuring unit, wherein the conversion unit and the measuring unit are communicated through a gas path; the conversion unit is provided with a gas inlet; the measuring unit comprises a measuring chamber, a first detector, an exhaust port and an analysis module; the conversion unit and the measuring unit share one light source; the light emitted by the light source generates ozone after passing through the conversion unit; and after passing through the light filtering module and the measuring unit, the light emitted by the light source reaches the first detector. The gas supply device has the advantages of simple structure, low cost, accurate measurement and the like and is applied to the supply of ozone.

Description

A kind of gas supply device

Technical field

The utility model relates to the gas supply, particularly the conversion of ozone with and spectral analysis.

Background technology

Generally include the ozone automatic analyzer in the monitoring sub-station of auto-monitor of surrounding air quality system, the ozone automatic analyzer utilizes spectroscopy measurement to go out the content of ozone in the atmosphere.Elongated along with service time, light source and the electronic devices and components in the ozone automatic analyzer can wear out, each position component also can change, and this just needs to use O ₃Gas is calibrated the ozone automatic analyzer, guarantees the accuracy of measuring.

O ₃Because its extremely strong oxidisability can not use steel cylinder to carry out canned and storage usually, so, when being calibrated, the ozone automatic analyzer need use ozone generating apparatus to transform out O at the scene ₃Gas.O ₃The generation of gas needs as lower device:

1, O ₃Generation device, normally used method have point discharge method or ceramic discharge method or ultraviolet light chemistry method etc.Specifically can be referring to patent CN2427509Y, CN2466135Y, CN2670334Y.

Point discharge method or ceramic discharge method are the most frequently used ozone generating method, can produce the ozone concentration of very high (reaching 50%), are mainly used in industrial generation ozone.But these methods are not suitable for producing the O of normal concentration ₃, because the O of its generation ₃The concentration precision is relatively poor, and can produce minor N O ₂, be applied to timing signal and can produce certain interference.

Ultraviolet light chemistry method can produce O high-precision, low concentration ₃, be fit to very much be applied to O ₃Demarcate.Ultraviolet light chemistry ratio juris is the UV-irradiation O of ultraviolet source emission ₂, a small amount of O ₂Can absorb the feature ultraviolet light of 185nm wavelength, be converted into O ₃, suc as formula (1).

O ₂+hv _185nm→O ₃ (1)

2, ozone photometer.The ozoniferous concentration accuracy in order to guarantee need feed the ozone that transforms out in the ozone photometer, utilizes spectral technique to record the concentration of ozone.The ozone photometer can be referring to patent CN2921827Y.

Ozone photometer measurement principle is to utilize O ₃Absorption to the ultraviolet light of 254nm wavelength obtains O ₃Concentration, ultimate principle is the Beer-Lambert relational expression, i.e. formula (2),

I＝I ₀·e ^-αLC (2)

Wherein, I ₀Be light source intensity, I is the light intensity of passing behind the tested gas, and L is a light path, and C is the concentration of tested gas, and α is the absorption coefficient of tested gas at specific wavelength.

Environment temperature and pressure can influence the density of sample gas, and the ultraviolet light that ozone is absorbed changes.According to formula (2), consider the influence of temperature, pressure, then (on average) concentration computing formula is,

$C=\ln \frac{I_0}{I}\×\frac{1}{\mathrm{\αL}}\×\frac{T}{273}\×\frac{29.92\mathrm{inHg}}{P}---\left(3\right)$

Wherein, P is the pressure of sample gas, and T is the temperature of sample gas.

In the prior art, above-mentioned ozone generating apparatus and ozone photometer all are splits, have many deficiencies, as:

1, complex structure need provide two gas compartments, is respectively applied for to produce and measure ozone.Need two ultraviolet sources of launching different characteristic wavelength ultraviolet light in ozone generating apparatus and the ozone photometer: the emission wavelength of ozone generating apparatus inner light source must comprise λ=185nm characteristic spectrum, O ₂Absorb this wavelength characteristic spectrum and can produce O ₃, and the emission wavelength of light source need comprise λ=254nm characteristic spectrum in the ozone photometer, but need to get rid of λ=185nm characteristic spectrum, avoid producing in the measuring process O ₃

2, operation inconvenience is in order to obtain light source intensity I in the ozone photometer ₀, at first need in photometric gas compartment, feed the air at zero point and (promptly not comprise O ₃Air), the light intensity that detector records promptly is light source intensity I ₀And, also to repeat aforesaid operations behind the some cycles at interval.

3, measuring accuracy is lower, owing to be not to monitor in the photometer light source intensity in real time to change, therefore, the light source intensity that prestores that utilizes when at every turn measuring might not be a light source intensity real when measuring, and has influenced measuring accuracy.

4, cost is higher, and when adopting ultraviolet irradiation technique, the ozone reforming unit needs two different ultraviolet sources with the ozone photometer, and the price of ultraviolet source is higher, has improved the cost of device.

The utility model content

In order to solve above-mentioned deficiency of the prior art, the utility model provides a kind of measurement accurate, simple in structure, lower-cost gas supply device.

For achieving the above object, the utility model adopts following technical scheme:

A kind of gas supply device, comprise light source, optical filtering module, conversion unit, measuring unit, be communicated with by gas circuit between conversion unit and measuring unit, on the described conversion unit air intake opening be set, described measuring unit comprises measuring chamber, first detector, exhausr port and analysis module; The shared light source of conversion unit and measuring unit, the light that described light source sends pass conversion unit and produce ozone, after the light that described light source sends passes optical filtering module, measuring unit, arrive described first detector.

Further, described conversion unit and measuring unit are in the both sides of light source.

As preferably, also be provided with second detector that the monitoring light source sends the light intensity of light, its output terminal connects analysis module, and second detector arrives the distance of optical filtering module less than first detector to the distance of light source.

The utility model compared with prior art has following beneficial effect:

1, simple in structure, maintainable good

The utility model can be designed to one with conversion unit and measuring unit, can only need a light source (or a detector): the special wavelength light in the light source emergent light is an ozone with oxygen conversion, and light source emergent light (or after being filtered specific wavelength) is used to measure ozone concentration.

2, measure accurately

The introducing of second detector can be monitored light source intensity in real time, and is used for follow-up Measurement and analysis, has further improved the accuracy of measuring.

Second detector can be monitored light source intensity in real time and change.

The measured signal of second detector can also be transferred to analysis module, and the driving voltage of FEEDBACK CONTROL ultraviolet source is stablized the output intensity of ultraviolet source, thereby improves ozoniferous precision.

3, cost is lower

Can need not to design two independently gas compartments, need not long breather line, only need a light source (or only needing a detector), these have all reduced cost.

Description of drawings

Fig. 1 is the structural representation of gas supply device among the utility model embodiment 1;

Fig. 2 is the schematic flow sheet of gas supply method in the present embodiment 1;

Fig. 3 is the structural representation of gas supply device among the utility model embodiment 2;

Fig. 4 is the structural representation of gas supply device among the utility model embodiment 3;

Fig. 5 is the structural representation of gas supply device among the utility model embodiment 4.

Embodiment

Below in conjunction with embodiment, the utility model is done further detailed description.

Embodiment 1:

As shown in Figure 1, a kind of calibrating gas feeding mechanism is used to provide the ozone gas, and described feeding mechanism comprises light source 11, conversion unit 1 and measuring unit 2.

Described conversion unit 1 is provided with air intake opening 12, and inside is provided with light source 11, as adopting mercury lamp, comprises wavelength X=185nm, 254nm in the light of light source 11 emissions.

Described measuring unit 2 connects conversion unit 1, and the gas in the converting unit 1 can freely flow in the measuring unit 2.Measuring unit 2 is provided with exhausr port 25, and inside is provided with optical filtering module 21, gas compartment 22, first detector 23, analysis module 24.Optical filtering module 21 will filter the light of wavelength X=185nm that light source sends, can adopt optical filter.The spacing L of optical filtering module 21 and light source 11 ₁Less, as 1mm, L ₁Much smaller than the distance L between the optical filtering module 21 and first detector 23.

Therefore the utility model only needs a light source, a gas compartment, need not long breather line, thereby whole apparatus structure is become simply, is convenient to safeguard, has also reduced cost simultaneously.

A kind of calibrating gas Supply Method in order to the ozone gas to be provided, as shown in Figure 2, said method comprising the steps of:

A, with zero gas (transform at wavelength X=185nm place ozone free, at the gas of λ=254nm place nothing absorption, as nitrogen) feed as described in conversion unit 1 and the measuring unit 2, the light intensity at wavelength X=254nm place that first detector 23 records is the light intensity I at wavelength X=254nm that light source 11 sends ₀, with light intensity I ₀ Analysis module 24 is advanced in storage.

The original gas that includes oxygen enters in the conversion unit 1 by air intake opening 12 with the flow of determining;

The light that light source 11 sends passes the original gas in the conversion unit 1, comprises wavelength X=185nm, 254nm in the light that light source sends; Oxygen in the original gas is converted into ozone under the effect of specific wavelength λ=185nm light;

Gas after the conversion enters in the gas compartment 22 in the measuring unit 2;

In conversion process, (light intensity is I to the light of wavelength X=254nm that light source 11 sends ₀) owing to the absorption of ozone in the conversion unit 1 be attenuated into C ₁Concentration for ozone in the conversion unit 1; L ₁Distance for light source 11 and optical filtering module 21;

B, the light that passes behind the conversion unit 1 pass optical filtering module 21, are filtered described specific wavelength λ=185nm, become measuring light;

Measuring light is passed the gas after transforming in the gas compartments 22 in the measuring unit 2, is absorbed by ozone and the back of decaying is received in the light intensity I at wavelength X=254nm place by first detector 23, and is converted to electric signal.Analysis module 24 utilizes the Beer-Lambert relational expression to obtain following computing formula, thereby obtains the concentration C of ozone in the measuring unit 2 interior gases:

$\mathrm{CL}+{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">L</figure-callout>}}_1=\frac{1}{\mathrm{\&alpha;}}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{I_0}{I}$

In above-mentioned concentration computing formula, the concentration C of ozone in the conversion unit 1 ₁Close usually with ozone concentration C in the measuring unit 2, and L ₁L is in a small amount relatively, therefore can ignore, and ozone concentration C is:

$C=\frac{1}{\mathrm{\&alpha;}\&CenterDot;L}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{I_0}{I}$

C, the gas that includes ozone are discharged from measuring unit 2 by exhausr port 25, thereby to the known gas of external world's supply ozone concentration value.

Embodiment 2:

As shown in Figure 3, a kind of calibrating gas feeding mechanism, be used to provide the ozone gas, as different from Example 1: second detector 13 also is set in conversion unit 1, be used for monitoring in real time the light intensity at wavelength X=254nm place that light source 11 sends light, second detector 13 arrives the distance of optical filtering module 21 less than first detector 13 to the distance of light source 11.

When feeding zero gas (transform at wavelength X=185nm place ozone free, at the gas of λ=254nm place nothing absorption, as nitrogen) in conversion unit 1, measuring unit 2, the light intensity that first detector 23 records is the light intensity I of wavelength X=254nm that light source 11 sends ₀, the light intensity that second detector 13 records is I ₁, light intensity I ₀With light intensity I ₁Between definite relation be: I ₀=kI ₁Thereby, obtain scale-up factor k, and store in the analysis module 24.

A kind of calibrating gas Supply Method in order to the ozone gas to be provided, said method comprising the steps of:

A, the original gas that includes oxygen enter in the conversion unit 1 by air intake opening 12 with the flow of determining;

The light that light source 11 sends passes the original gas in the conversion unit 1, comprises wavelength X=185nm, 254nm in the light that light source sends; Oxygen in the original gas is converted into ozone under the effect of specific wavelength λ=185nm light;

Gas after the conversion enters in the gas compartment 22 in the measuring unit 2;

In conversion process, the light of wavelength X=254nm that light source 11 sends owing to the absorption of ozone in the conversion unit 1 be attenuated into

C ₁Concentration for ozone in the conversion unit 1; L ₁For the distance of light source 11 and optical filtering module 21, very little usually, as 1mm, L ₁Much smaller than the distance L between the optical filtering module 21 and first detector 23.

The light of wavelength X=254nm that light source 11 sends is received by second detector 13 after passing ozone in the conversion unit 1, and the light intensity that second detector 13 receives is $I_2=I_1\&CenterDot;e^{-\mathrm{\&alpha;}{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">L</figure-callout>}}_2},$ L ₂Be the distance of second detector 13 to light source, very little usually, as 1mm, L ₂Much smaller than the distance L between the optical filtering module 21 and first detector 23.

Therefore, by the light intensity that second detector 13 removes to monitor in real time wavelength X=254nm that light source 11 sends, saved and fed zero gas (in order to obtain the light intensity I of wavelength X=254nm that light source 11 sends ₀) trouble, solved the deficiency that can not monitor light source intensity in real time, improved the accuracy that ozone concentration is measured.

B, the light that passes behind the conversion unit 1 pass optical filtering module 21, are filtered described specific wavelength λ=185nm, become measuring light;

Measuring light is received in the light intensity I at wavelength X=254nm place by first detector 23, and is converted to electric signal after passing gas after transforming in the gas compartments 22 in the measuring unit 2.The relational expression of the light intensity I that the ozone concentration C and first detector receive in the measuring unit 2 as shown in the formula,

$C\&CenterDot;L+{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">L</figure-callout>}}_1=\frac{1}{\mathrm{\&alpha;}}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{I_0}{I}$

Ozone concentration C in the conversion unit 1 ₁The light intensity I that receives with second detector 13 ₂Relational expression as shown in the formula,

${\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">L</figure-callout>}}_2=\frac{1}{\mathrm{\&alpha;}}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{I_1}{I_2}$

So, by top two formulas and relational expression I ₀=kI ₁Can obtain:

$C\&CenterDot;L+{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;L_1-{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">C</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H2009201985255E00021.png,H2009201985255E00022.png"\; state="\{\{state\}\}">L</figure-callout>}}_2=\frac{1}{\mathrm{\&alpha;}}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{k\&CenterDot;I_2}{I}$

In above-mentioned concentration computing formula, the concentration C of ozone in the conversion unit 1 ₁Close usually with ozone concentration C in the measuring unit 2, and L ₁, L ₂L is in a small amount relatively, therefore can ignore C ₁L ₁And C ₁L ₂, ozone concentration C is:

$C=\frac{1}{\mathrm{\&alpha;}\&CenterDot;L}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{k\&CenterDot;I_2}{I}$

C, the gas that includes ozone are discharged from measuring unit 2 by exhausr port 25, thereby to the known gas of external world's supply ozone concentration value.

Embodiment 3:

As shown in Figure 4, a kind of calibrating gas feeding mechanism is used to provide the ozone gas, as different from Example 2: exhausr port 14 is set on conversion unit 1, like this, a gas part that produces in the conversion unit 1 is passed in the measuring unit 2, is used for measuring the concentration value that transforms ozone in the gas of back; Another part is then discharged by exhausr port 14, thereby to the known gas of external world's supply ozone concentration value.

A kind of calibrating gas Supply Method, in order to the ozone gas to be provided, as different from Example 2, in step c, the gas after the conversion is discharged from conversion unit 1 by exhausr port 14, thereby to the known gas of external world's supply ozone concentration value.

Embodiment 4:

As shown in Figure 5, a kind of calibrating gas feeding mechanism is used to provide the ozone gas, and described feeding mechanism comprises light source 11, is in the conversion unit 1 and the measuring unit 2 of light source 11 both sides.

Described conversion unit 1 is provided with air intake opening 12, exhausr port 14.

Described measuring unit 2 is provided with air intake opening 26, exhausr port 25, is provided with first detector 23, analysis module 24.Described exhausr port 14 and air intake opening 26 are communicated with.

Light source 11 adopts mercury lamp, comprises wavelength X=185nm, 254nm in the light of light source 11 emissions.Optical filtering module 21 is attached on the light source 11, filters the light of wavelength X=185nm.

A kind of calibrating gas Supply Method in order to the ozone gas to be provided, said method comprising the steps of:

A, with in the measuring unit 2 as described in zero gas (not having the gas that absorbs at λ=254nm place) feeding as nitrogen, the light intensity at wavelength X=254nm place that first detector 23 records is the light intensity I at wavelength X=254nm that light source 11 sends ₀, with light intensity I ₀ Analysis module 24 is advanced in storage.

The original gas that includes oxygen enters in the conversion unit 1 by air intake opening 12 with the flow of determining;

The light that light source 11 sends passes the original gas in the conversion unit 1, and the light that light source 11 sends comprises that oxygen in wavelength X=185nm, the 254nm original gas under the effect of specific wavelength λ=185nm light, is converted into ozone;

Gas after the conversion enters in the measuring unit 2 by exhausr port 14, air intake opening 26;

The light that b, light source 11 send passes optical filtering module 21, is filtered described specific wavelength λ=185nm, becomes measuring light;

Measuring light is received by first detector 23 after passing gas in the measuring unit 2, obtains the light intensity I at wavelength X=254nm place, and is converted to electric signal, and analysis module 24 utilizes following computing formula (formula 3 in the background technology) to obtain the concentration value of ozone:

$C=\frac{1}{\mathrm{\&alpha;}\&CenterDot;L}\&CenterDot;\frac{T}{273}\&CenterDot;\frac{29.92\mathrm{inHg}}{P}\&CenterDot;\ln \frac{I_0}{I}$

Wherein, I ₀Represent measuring light light intensity at wavelength X=254nm place when entering measuring unit 2, in step a, obtain.

Gas after c, the conversion is discharged from conversion unit 1 by exhausr port 14, thereby to the known gas of external world's supply ozone concentration value.

Supplemental instruction about the foregoing description: all adopt the absorption spectroanalysis technology in the foregoing description, can certainly adopt other spectral analysis technique, these technology all are the common practise of this area, do not repeat them here.

Above-mentioned embodiment should not be construed as the restriction to the utility model protection domain.Key of the present utility model is that the special wavelength light that utilizes light source to send acts on the oxygen in the original gas, changes into ozone; The light that light source sends passes the gas after the conversion, utilizes spectral technique to obtain the concentration value of ozone in the gas.Under the situation that does not break away from the utility model spirit, any type of change that the utility model is made all should fall within the protection domain of the present utility model.

Claims (3)

1. gas supply device, comprise light source, optical filtering module, conversion unit, measuring unit, be communicated with by gas circuit between conversion unit and measuring unit, on the described conversion unit air intake opening be set, described measuring unit comprises measuring chamber, first detector, exhausr port and analysis module; The shared light source of conversion unit and measuring unit, the light that described light source sends passes conversion unit and produces ozone, after the light that described light source sends passes optical filtering module, measuring unit, arrives described first detector.

2. device according to claim 1 is characterized in that: described conversion unit and measuring unit are in the both sides of light source.

3. device according to claim 1 and 2 is characterized in that: also be provided with second detector that the monitoring light source sends the light intensity of light, its output terminal connects analysis module, and second detector arrives the distance of optical filtering module less than first detector to the distance of light source.

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