CN104280355B - Ammonia gas and sulfur dioxide gas concentration detection apparatus and the detection method - Google Patents

Ammonia gas and sulfur dioxide gas concentration detection apparatus and the detection method Download PDF

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CN104280355B
CN104280355B CN 201410578821 CN201410578821A CN104280355B CN 104280355 B CN104280355 B CN 104280355B CN 201410578821 CN201410578821 CN 201410578821 CN 201410578821 A CN201410578821 A CN 201410578821A CN 104280355 B CN104280355 B CN 104280355B
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ammonia
sulfur dioxide
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董作人
郁敏捷
孙延光
蔡海文
叶青
刘铭晖
魏芳
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中国科学院上海光学精密机械研究所
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一种氨气和二氧化硫气体浓度的检测装置和检测方法,该装置由紫外光源、准直透镜、转轮、气体吸收池、会聚透镜、紫外光纤、光谱仪和计算机组成;解决了两种气体吸收谱线的FFT特征频率处峰值相互干扰的问题。 Detection apparatus and method for detecting the concentration of ammonia gas and sulfur dioxide gas, which means the ultraviolet light source, a collimator lens, a runner, a gas absorption cell, a condenser lens, UV fiber, a spectrometer and a computer; address two gas absorption spectrum problems FFT line peak characteristic frequencies interfering with each other. 本发明具有无需测量气体吸收截面、计算简单、响应速度快等优点,无需用温度与压强来修正吸收截面,因此成本低,且稳定性好。 The present invention has no need to measure gas absorption cross section, the calculation is simple, fast response speed, etc., without the pressure and temperature corrected absorption cross-section, resulting in low cost and good stability.

Description

氨气和二氧化硫气体浓度的检测装置和检测方法 Ammonia gas and sulfur dioxide gas concentration detection apparatus and the detection method

技术领域 FIELD

[0001] 本发明涉及气体浓度检测,特别是一种氨气和二氧化硫气体浓度的检测装置和检测方法。 [0001] The present invention relates to a gas concentration detection, particularly an ammonia gas and sulfur dioxide gas concentration detection apparatus and the detection method.

背景技术 Background technique

[0002] 随着我国经济的发展,电力和煤炭的消耗日益增多,火力发电会产生大量的氮氧化物和二氧化硫,对环境造成危害,因此是全国节能减排的重点之一。 [0002] As China's economic development, electricity and coal consumption increasing, thermal power will produce large amounts of nitrogen oxides and sulfur dioxide, causing harm to the environment, and therefore is one of the key national energy conservation. 一般对燃煤电厂氮氧化物减排用选择性催化还原(SCR)烟气脱硝技术。 Usually fired power plant emissions of nitrogen oxides reduction (SCR) flue gas denitrification technique using selective catalytic. 其中用于脱硝的NH3逃逸是该过程控制的关键指标之一。 NH3 denitration escape wherein one of the key indicators of the process control. 对于氨气(NH3)浓度的检测,相比于传统的电化学方法,光学法具有非接触、 快速和灵敏度高等特点,被广泛应用于工业过程的监测与监控以及工业废气排放的连续在线监测等,如非分散红外分析法、差分吸收光谱法、可调谐二极管激光吸收光谱法等。 For detecting the concentration of ammonia (NH3), as compared to conventional electrochemical methods, an optical non-contact method, rapid and high sensitivity, it is widely used in monitoring, and monitoring and continuous online monitoring of industrial emissions of industrial processes and the like , such as non-dispersive infrared analysis, differential absorption spectroscopy, tunable diode laser absorption spectroscopy method. 一台二极管激光器只能测量一种气体,若要同时检测多种气体,需要增加激光器数量,成本高, 也难于集成。 A diode laser can only measure one gas, to detect a variety of gases at the same time, the need to increase the number of lasers, high cost, difficult to integrate. 非分散红外分析法及差分吸收光谱法可用于多组分气体的测量。 Non-dispersive infrared analysis and differential optical absorption spectroscopy can be used to measure a multi-component gas.

[0003] 在先技术一,利用非分散红外技术测量气体浓度,见《专利:非分散红外多组分烟气分析仪[P] .2011》。 [0003] a prior art, the use of non-dispersive infrared gas concentration measurement, see "Patent: multi-component non-dispersive infrared gas analyzer [P] .2011". 这一装置含有一个光学滤波轮,滤波轮上的多个窄带滤光片将宽带(1 〜10M1)的红外光分成多个波段,每个波段对应一种气体的吸收,红外光经多次反射吸收池被红外探测器接收,经处理计算得出各种气体的浓度。 The optical filtering means comprises a wheel, a plurality of narrowband filter wheel on a broadband filter (1 ~10M1) infrared light into a plurality of bands, each corresponding to one gas absorption, infrared light is reflected a plurality of times cuvette is received by an infrared detector, the processed calculated concentrations of various gases. 多次反射吸收池的使用增加了吸收光程,提高了精度,但该技术使用的前提是各组分气体无交叉重叠吸收,且稳定性没有差分吸收光谱法好。 Multiple reflection absorption cell is used to increase the absorption path, improve the accuracy, but only if this technique is used for each component gas absorption without overlap, and no good stability differential optical absorption spectroscopy.

[0004] 在先技术二,利用吸收截面测量气体浓度,见《专利:同时监测二氧化硫和一氧化氮气体浓度的便携装置及测量方法[P] . 2008》。 [0004] The prior art two, using the measured gas concentration absorption cross-section, see "Patent: simultaneous monitoring apparatus and the portable gas concentration measuring method of sulfur dioxide and nitric oxide [P] 2008.". 这一方法依据SOdPNO气体在两个波段处的吸收峰不同特征,测量SO2和NO气体浓度,S〇2在200nm和300nm波段都有明显的吸收峰,而NO 气体在300nm波段处没有吸收峰。 The method according SOdPNO gas peaks at two different characteristic absorption bands at the measured concentrations of SO2 and NO gas, S〇2 have significant absorption peaks at 200nm and 300nm band, and NO gas in the band no absorption peak at 300nm. 具体实施:首先利用300nm波段SO2气体的吸收谱线计算SO2 气体浓度,然后选择200nm波段与S〇2有重叠吸收的NO气体的一个吸收峰(226nm),利用300nm波段测量得到的SO2浓度与226nm处的吸收谱线计算得到NO气体浓度。 DETAILED DESCRIPTION: Firstly 300nm band SO2 gas absorption lines of the gas concentration is calculated SO2, then select a peak of 200nm absorption band overlapping with S〇2 have absorbed NO gas (226nm), 300nm band by using the measured concentrations of SO2 and 226nm absorption lines at the gas concentration calculated NO. 该技术可用于测量SOdPNH3混合气体的浓度,但需测量气体的吸收截面,而吸收截面会随温度压力等因素改变,精确测量需要对其做温度与压力的修正,计算过程复杂。 This technique can be used to measure the concentration SOdPNH3 mixed gas, but the gas to be measured absorption cross-section, and the absorption cross section varies with temperature pressure and other factors, accurate measurement requires correction for temperature and pressure thereof, calculation complexity.

[0005] 在先技术三,运用傅里叶变换测量气体浓度,见《文献:傅里叶变换在差分吸收光谱技术气体浓度计算中的应用[J].光谱学与光谱分析,2008,28 (12) : 2830-2834》。 [0005] The three prior art, the use of Fourier transform gas concentration measurement, see "Document: Fourier transform calculation of gas concentration differential optical absorption spectroscopy technology application [J] and Spectral Analysis, 2008,28 ( 12): 2830-2834. " 该技术对SO2、NO、NO2等具有准周期特性的吸收光谱做傅里叶变换,利用特征频率的幅值与气体浓度呈线性关系从而反演气体的浓度。 This technique has a quasi-periodic characteristics of SO2, NO, NO2 and other absorption spectra in the Fourier transform, the amplitude and frequency characteristics of the gas concentration using a linear relationship between the concentration of gas such inversion. 但是当两种气体在同一波段的准周期吸收特性相同或者相近时,两种气体的相互影响将会十分严重,由于两种气体的吸收谱线非绝对周期,一方的吸收会对另一方的FFT峰值也有贡献,直接运用FFT特征频率处的峰值来同时反演两种气体浓度将产生较大的误差,特别是在高SO2气体浓度(5000〜IOOOOppm)下,无法精确测量200〜230nm波段与S〇2有严重重叠吸收的低NH3气体的浓度(0〜20ppm)。 But when the same two gases in the same band of quasi-periodic absorption characteristics or similar mutual influence of the two gases will be very serious, because the FFT absorption lines of the two gases not absolutely cycle, one would absorb the other also contribute to peak, direct use of the peak FFT characteristic frequencies simultaneously inversion of the two gases will have a greater concentration of errors, especially at high concentrations of SO2 gas (5000~IOOOOppm), can not accurately measure the S band 200~230nm 〇2 have a low concentration of NH3 gas is absorbed overlapping (0~20ppm).

发明内容 SUMMARY

[0006] 本发明的目的是为了解决上述在先技术的不足,利用氨气与二氧化硫气体的吸收谱线具有准周期性规律的特点,提供一种氨气和二氧化硫气体浓度的检测装置和检测方法,解决两种气体吸收谱线的FFT特征频率处峰值相互干扰的问题。 [0006] The object of the present invention is to solve the problem of the above-described prior art, the use of ammonia gas and sulfur dioxide gas absorption lines having the characteristics of a quasi-periodic law, to provide detection apparatus and method for detecting the concentration of ammonia gas and sulfur dioxide , FFT peak at a frequency characteristic absorption lines of the two gases to solve interference problems. 无需测量气体吸收截面,计算简单,可在高SO2气体浓度(5000〜IOOOOppm)下精确测量低NH3气体浓度(0〜 20ppm) 〇 Without measuring gas absorption cross-section, simple calculation can accurately measure low concentrations of NH3 gas (0~ 20ppm) under (5000~IOOOOppm) SO2 gas at a high concentration billion

[0007] 本发明的技术解决方案如下: [0007] The technical solutions of the present invention are as follows:

[0008] —种氨气和二氧化硫气体浓度的检测装置,其特点在于该装置由紫外光源、准直透镜、转轮、气体吸收池、会聚透镜、紫外光纤、光谱仪和计算机组成;沿所述的紫外光源发出的紫外光依次是所述的准直透镜、转轮上的氮气参比气室或氨气参比气室、气体吸收池、 会聚透镜、紫外光纤,该紫外光纤的输出端连接光谱仪的接收端,该光谱仪的输出端接计算机的输入端; [0008] - seed ammonia and sulfur dioxide gas concentration detection means, characterized in that the apparatus by a UV light source, a collimator lens, a runner, a gas absorption cell, a condenser lens, UV fiber, a spectrometer and a computer; along said UV ultraviolet light source is emitted sequentially said collimator lens, a nitrogen gas or ammonia gas reference cell on the reference gas chamber wheel, a gas absorption cell, a condenser lens, an ultraviolet optical fiber output end of the optical fiber connected to the ultraviolet spectrometer receiving terminal, an input terminal of the computer output termination spectrometer;

[0009] 所述的氨气参比气室的氨气浓度为IOOOppm〜2000ppm; [0009] The ammonia concentration of the reference gas chamber ammonia ratio IOOOppm~2000ppm;

[0010] 所述的紫外光源为氙灯、氘灯或卤钨灯,发射的光波段覆盖185〜400nm; [0010] The UV source is a xenon lamp, a deuterium lamp or tungsten halogen lamps, light emitting wavelength band covering 185~400nm;

[0011] 利用上述氨气和二氧化硫气体浓度的检测装置检测氨气和二氧化硫气体浓度的方法,其特点在于该方法包括如下步骤: [0011] With the method for detecting the concentration of ammonia gas and sulfur dioxide gas and the ammonia gas concentration of sulfur dioxide detection means, characterized in that the method comprises the steps of:

[0012] 步骤一、标定: [0012] Step a calibration:

[0013] 1)在所述的气体吸收池充入氮气,将所述的氮气参比气室通过转轮置于光路中, 启动所述的紫外光源和计算机,紫外光源发出紫外光经准直透镜后变成平行光通过高浓度氮气参比气室,入射到气体吸收池,从气体吸收池出射的光经会聚透镜聚焦耦合进紫外光纤输入到所述的光谱仪的接收端,光谱仪输出的数据信号输入所述的计算机,计算机通过软件采集得到背景光强Io (λ); [0013] 1) in the absorption cell charged with nitrogen gas, the reference gas chamber is nitrogen gas in the optical path, starts by turning the UV light sources and a computer, the ultraviolet light source emits ultraviolet light collimated after the lens into parallel light by the nitrogen-enriched gas reference cell, enters the gas absorption cell, the focus is coupled into the ultraviolet optical input to the receiver of the spectrometer from the gas absorption cell the light emitted through the converging lens data of the spectrometer output the computer input signal, the computer to obtain background light intensity Io (λ) collected by the software;

[0014] 2)在所述的气体吸收池充入浓度为IOOOppm的二氧化硫气体,将所述的氨气参比气室通过转轮置于光路中,紫外光源发出紫外光经准直透镜后变成平行光通过高浓度氨气参比气室,入射到气体吸收池,从气体吸收池出射的光经会聚透镜聚焦耦合进紫外光纤输入到所述的光谱仪的接收端,光谱仪输出的数据信号输入所述的计算机,计算机通过软件采集得到气体吸收后的光强I1 (λ); [0014] 2) in the gas absorption cell is charged at a concentration of IOOOppm of sulfur dioxide gas, the ammonia gas chamber through the reference wheel in the optical path, the ultraviolet light source emits ultraviolet light after the collimator lens becomes into parallel light by a high concentration of ammonia reference gas chamber, enters into a gas absorption cell, a light through the converging lens from the gas absorption cell exit focus coupled into the ultraviolet optical input to the receiver of the spectrometer, a data signal input spectrometer output the computer, computer software, obtained by collecting the gas absorption intensity I1 (λ);

[0015] 3)计算机对数据信号进行计算处理,选取195〜225nm的光谱数据,根据Beer-Lambert定律:I1 (λ) = 1〇(λ) exp (-σ (λ) CL),σ (λ)为吸收截面,C为气体浓度,L为吸收长度,得到吸收度 [0015] 3) a computer data signal calculation processing, spectral data 195~225nm select, according to the Beer-Lambert law: I1 (λ) = 1〇 (λ) exp (-σ (λ) CL), σ (λ ) is the absorption cross-section, C is the concentration of the gas, L is the length of the absorbent, absorption to give

Figure CN104280355BD00051

其中i表示气体组分;由于待测对象多为混合气体和颗粒的混合物,所以存在水蒸气的吸收、CCD的响应、米氏散射、瑞利散射因素的影响,因而吸收度分为快变(λ)和慢变(λ)两部分: Where i represents the gas component; mostly due to the object to be measured and the gas mixture was mixed particles, so that the presence of water vapor absorption, the impact response of the CCD Mie scattering, Rayleigh scattering factors and thus becomes faster absorption into ( [lambda]) and slowly varying ([lambda]) of two parts:

Figure CN104280355BD00052

[0019] 其中εΚ、εΜ分别表示瑞利散射系数和米氏散射系数,是随波长快速变化的窄带吸收截面,〇lb是随波长缓慢变化的宽带吸收截面;对由195〜225nm的光谱数据计算得到的吸收度〇1(1)进行五阶多项式拟合,得到拟合系数&1、131、(31、(11、61、£1,吸收度慢变部分表示为: [0019] wherein εΚ, εΜ represent Rayleigh scattering and Mie scattering coefficient coefficient, is rapidly changing with wavelength narrowband absorption cross section, 〇lb is slowly varying with wavelength broadband absorption cross section; calculated from the spectral data of 195~225nm the resulting absorbance 〇1 (1) for fifth order polynomial fitting, fitting coefficients to obtain & amp; 1,131, (31, (11,61, £ 1, the absorbance of the slowly varying part is expressed as:

[0020] [0020]

Figure CN104280355BD00061

[0021] 差分吸收度 [0021] Differential absorbance

Figure CN104280355BD00062

对具有准周期性规律的差分吸收度D71 (λ)进行傅里叶变换,得到二氧化硫气体的特征峰值 Wherein the difference Fourier transform absorbance D71 (λ) has a quasi-periodic law, sulfur dioxide gas obtained peak

Figure CN104280355BD00063

:

[0022] 4)重复步骤2)、3),所不同的是在所述的气体吸收池依次充入浓度为1500、2000、 2500、3000、3500、4000、4500、5000??111的二氧化硫气体,分别得到二氧化硫气体的特征峰值 [0022] 4) repeating steps 2), 3), except that a concentration of 1500, 2000 are sequentially charged in the gas absorption cell, the sulfur dioxide gas 111 2500,3000,3500,4000,4500,5000 ?? characteristic peak, respectively sulfur dioxide gas

Figure CN104280355BD00064

[0023] 5)用最小二乘法对二氧化硫气体的特征峰值A02与二氧化硫的气体浓度Cs〇2进行线性拟合,得到拟合系数Hi1、m, [0023] 5) by the least square method wherein sulfur dioxide gas peak concentration of sulfur dioxide gas A02 Cs〇2 linear fitting, fitting coefficients obtained Hi1, m,

Figure CN104280355BD00065

[0024] 6)重复步骤2)、3),所不同的是在所述的气体吸收池充入浓度分别为2、4、6、8、10、 12、14、16、18、20ppm的氨气以及IOOOppm的二氧化硫混合气体,用最小二乘法对氨气的特征峰值Ah3与氨气浓度Cnh3进行线性拟合,得到拟合系数m2、n2,所述的氨气浓度 [0024] 6) repeating steps 2), 3), except that in the gas absorption cell charged respectively 2,4,6,8,10 12,14,16,18,20ppm concentrations of ammonia, sulfur dioxide gas and a mixed gas of IOOOppm, characterized by the least square method ammonia and the ammonia concentration peak Ah3 Cnh3 linear fitting, fitting coefficients to obtain m2, n2, the ammonia concentration

Figure CN104280355BD00066

[0025] 7)重复步骤6),所不同的是二氧化硫的浓度依次换成1500、2000、2500、3000、 3500、4000、4500、5000??111,得到不同二氧化硫浓度下的氨气的特征峰值&11,与氨气浓度Qh1线性拟合公式,所述的拟合系数肥与二氧化硫浓度Cs〇2近似三次函数关系,通过三次拟合得到拟合系数Pl、P2、P3、P4, [0025] 7) Repeat step 6), except that the concentration of sulfur dioxide are sequentially replaced 1500,2000,2500,3000, 3500,4000,4500,5000 ?? 111 to obtain characteristic peaks at different ammonia concentrations of sulfur dioxide & amp; 11, and the ammonia concentration Qh1 linear fitting equation, fitting the fertilizer and the sulfur dioxide concentration coefficient Cs〇2 cubic function approximation, cubic fit obtained by fitting coefficients Pl, P2, P3, P4,

Figure CN104280355BD00067

所述的拟合系数Π2与二氧化硫浓度Cs02近似线性关系,通过线性拟合得到系数Φ、q2,所述的拟合系数 The fitting coefficients Π2 Cs02 and sulfur dioxide concentration is approximately linear, obtained by linear fitting coefficients Φ, q2, said fitting coefficient

Figure CN104280355BD00068

[0026] 步骤二、测量: [0026] Step II Measurement:

[0027] 1)重复步骤一中的2)、3),所不同的是在所述的气体吸收池充入待测氨气和二氧化硫混合气体,得到经参考气室氨气、待测氨气和二氧化硫混合气体吸收后的光强I2 (λ), 计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氮气参比气室和氨气、二氧化硫混合气体吸收的吸收度D2 (λ),D2 (λ) =D'2 (λ) +D〃2 (λ),对由195〜225nm的光谱数据计算得到的吸收度D2 (λ)进行五阶多项式拟合, [0027] 1) Repeat steps 2), 3), except that in the gas absorption cell charged with a mixed gas of sulfur dioxide and ammonia gas to be measured, to obtain the reference gas chamber via an ammonia gas, ammonia test after a mixed gas of sulfur dioxide and the absorption intensity I2 (λ), the computer data signal optical transmission spectrometer was calculated to give the degree of absorption wavelength of 195~225nm D2 of the reference gas chamber with nitrogen and ammonia, a mixed gas of sulfur dioxide absorbed (λ), D2 (λ) = D'2 (λ) + D〃2 ([lambda]), to be calculated from the absorbance spectral data 195~225nm D2 (λ) for fifth order polynomial fitting,

Figure CN104280355BD00069

€2,得到拟合系数32、62、02、(12、62、;^2,差分吸收 2 €, fitting coefficients obtained 32,62,02, (12, 62,; ^ 2, differential absorption

Figure CN104280355BD000610

对具有准周期性规律的差分吸收度d'2 (λ)进行傅里叶变换,得到待测二氧化硫气体的特征峰值,通过下式计算二氧化硫气体浓度Cso2 : Differential absorption of the periodicity of the quasi d'2 (λ) Fourier transform, wherein the peak measured sulfur dioxide gas, sulfur dioxide gas calculated by the concentration Cso2:

[0028] [0028]

Figure CN104280355BD000611

[0029] 2)重复步骤二中的1),所不同的是:转轮转动180°,切换到氮气参比气室,得到待测氨气和二氧化硫混合气体吸收后的光强I3 (λ),计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氮气参比气室和氨气、二氧化硫混合气体吸收的吸收度D3 (λ),D3 (λ) =D73 (λ) +D〃3 (λ),对由195〜225nm的光谱数据计算得到的吸收度D3㈨进行五阶多项式拟合: The two 1 [0029] 2) repeating step), except that: the wheel is rotated 180 °, switching to a nitrogen reference gas chamber, after the test to obtain a mixed gas of ammonia and sulfur dioxide absorbed light intensity I3 (λ) computer data signal optical transmission spectrometer was calculated to give a wavelength of 195~225nm reference gas chamber with nitrogen and ammonia, a mixed gas of sulfur dioxide absorbed absorbance D3 (λ), D3 (λ) = D73 (λ) + D〃3 (λ), the absorption spectrum of the data obtained from the D3㈨ calculated 195~225nm fifth order polynomial fit is performed:

Figure CN104280355BD00071

得到拟合系数a3、b3、C3、d3、Θ3、f3,差分吸收度 Fitting coefficients obtained a3, b3, C3, d3, Θ3, f3, differential absorption of

Figure CN104280355BD00072

,对具有准周期性规律的差分吸收度(λ)进行傅里叶变换,得到氨气气体的特征峰值^3,通过下式计算氨气的浓度: , The difference of the periodicity of quasi Fourier transformation absorbance ([lambda]), wherein the peak of the ammonia gas to give 3 ^, calculated by the concentration of ammonia:

[0030] [0030]

Figure CN104280355BD00073

[0031] 本发明的技术效果如下: [0031] Technical effects of the present invention are as follows:

[0032] 本发明利用傅里叶变换方法,加入高浓度氨气参比气室与氮气参比气室,并通过转轮实现两者的切换,与在先技术三相比,解决傅里叶变换法不能测量两种准周期吸收特性相同或相近的气体,克服SO2和NH3两种气体吸收谱线的FFT特征频率处峰值相互干扰的问题,能够同时测出SOdPNH3气体的浓度,相较于在先技术二所用的差分吸收光谱法,本发明具有无需测量气体吸收截面、计算简单、响应速度快等优点,无需用温度与压强来修正吸收截面,因此成本低,稳定性好。 [0032] The present invention utilizes a Fourier transform, addition of a high concentration of ammonia nitrogen and the reference gas chamber reference gas chamber, and to achieve both of the switching by the wheel, compared with the three prior art, to solve a Fourier transformation can measure two kinds of quasi-periodic absorption characteristics identical or similar gas, to overcome the problems FFT peak characteristic frequencies of the two gases SO2 and NH3 absorption line interference can be measured simultaneously SOdPNH3 gas concentration, compared to the used in prior art two differential optical absorption spectroscopy, the present invention has no need to measure gas absorption cross section, the calculation is simple, fast response speed, etc., without the pressure and temperature corrected absorption cross section, and therefore low cost, good stability.

附图说明 BRIEF DESCRIPTION

[0033] 图1是本发明氨气和二氧化硫气体浓度的检测装置的结构框图; [0033] FIG. 1 is a block diagram of the present invention, ammonia and sulfur dioxide gas concentration detection apparatus of;

[0034] 图2是本发明所述的二氧化硫气体在183〜227nm波段的吸收截面; [0034] FIG. 2 is a cross section of the absorption band at 183~227nm sulfur dioxide gas according to the present invention;

[0035] 图3是本发明所述的氨气在170〜230nm波段的吸收截面; [0035] FIG. 3 is a cross-sectional ammonia absorption band at 170~230nm the present invention;

[0036] 图4是本发明所述氨气与二氧化硫混合气体的FFT幅值图; [0036] FIG. 4 is a magnitude plot of the FFT of the present invention, a mixed gas of ammonia gas and sulfur dioxide;

[0037] 图5是本发明所述方法的测量流程图。 [0037] FIG. 5 is a flowchart illustrating the measuring method of the present invention.

具体实施方式 detailed description

[0038] 下面结合实例与附图对本发明进一步说明,但不限于此。 [0038] The following examples in conjunction with the accompanying drawings of the present invention is further illustrated, but is not limited thereto.

[0039] 实施例一 [0039] Example a

[0040] 请参阅图1,图1是本发明氨气和二氧化硫气体浓度的检测装置的结构框图,由图可见,本发明氨气和二氧化硫气体浓度的检测装置由紫外光源1、准直透镜2、转轮3、氮气参比气室301、氨气参比气室302、气体吸收池4、会聚透镜5、紫外光纤6、光谱仪7和计算机8组成;紫外光源1发出的紫外光经过准直透镜2变成平行光通过转轮3上的参比气室并入射至气体吸收池4,会聚透镜5将从气体吸收池出射的光输出耦合进紫外光纤6,紫外光纤6连接光谱仪7的接收端,光谱仪7将数据信号传输到计算机8,计算机8对数据信号进行处理,反演出气体浓度。 [0040] Referring to FIG. 1, FIG. 1 is a block diagram of the present invention, ammonia and sulfur dioxide gas concentration detection apparatus is seen from the figure, according to the present invention, ammonia and sulfur dioxide gas concentration detected by the ultraviolet light source means 1, the collimator lens 2 , runner 3, reference gas chamber 301 of nitrogen, ammonia reference gas chamber 302, the gas absorption cell 4, a condenser lens 5, an ultraviolet optical fiber 6, a spectrometer 7 and 8 consisting of a computer; ultraviolet light emitted from the ultraviolet light source 1 is collimated lens 2 into parallel light by the reference cell 3 and is incident on the reel to a gas absorption cell 4, the light outcoupling converging lens 5 from the gas absorption cell into the outgoing ultraviolet optical fiber 6, the optical fiber 6 is connected to receiving ultraviolet spectrometer 7 end, the spectrometer 7 8 data signal to the computer, the computer 8 data signal processing, gas concentration was deduced.

[0041] 本实施方式的步骤如下: [0041] The procedure of the present embodiment is as follows:

[0042] 步骤一、标定: [0042] Step a calibration:

[0043] 1)在所述的气体吸收池4充入氮气,将所述的氮气参比气室301通过转轮3置于光路中,启动所述的紫外光源1和计算机8,紫外光源1发出紫外光经准直透镜2后变成平行光通过高浓度氮气参比气室301,入射到气体吸收池4,从气体吸收池4出射的光经会聚透镜5 聚焦耦合进紫外光纤6输入到所述的光谱仪7的接收端,光谱仪7输出的数据信号输入所述的计算机8,计算机8通过软件采集得到背景光强Io (λ); [0043] 1) the gas absorption cell 4 is charged with nitrogen, the nitrogen gas chamber 301 through the reference wheel in the optical path 3, the start of the ultraviolet light source 1 and the computer 8, the ultraviolet light source 1 by emitting ultraviolet light into a parallel light after the collimator lens 2 by a high concentration of nitrogen reference gas chamber 301, the gas enters the absorption cell 4, the gas absorption cell 4 emitted light is coupled into the converging lens 5 to focus the UV to the input optical fiber 6 said output data signal input to the receiving end 7 of the spectrometer, the spectrometer 7 8 computers, computer software acquisition 8 obtained background light intensity Io (λ);

[0044] 2)在所述的气体吸收池4充入浓度为IOOOppm的二氧化硫气体,将所述的氨气参比气室302通过转轮3置于光路中,紫外光源1发出紫外光经准直透镜2后变成平行光通过高浓度氨气参比气室302,入射到气体吸收池4,从气体吸收池4出射的光经会聚透镜5聚焦耦合进紫外光纤6输入到所述的光谱仪7的接收端,光谱仪7输出的数据信号输入所述的计算机8,计算机8通过软件采集得到气体吸收后的光强I1 (λ); [0044] 2) in the gas absorption cell 4 is charged at a concentration of IOOOppm of sulfur dioxide gas, the ammonia reference gas chamber 302 through the reel 3 is placed in the optical path, the ultraviolet light source 1 emits ultraviolet light collimated by after the collimator lens 2 into parallel light by a high concentration of ammonia reference gas chamber 302, the gas enters the absorption cell 4, the gas absorption cell 4 emitted light is coupled into the converging lens 5 focuses the optical fiber 6 is inputted to ultraviolet spectrometer of said output data signal input terminal 7 is received, the computer 8 spectroscope 7, 8 by computer software collects the gas obtained after the absorption intensity I1 (λ);

[0045] 3)计算机8对数据信号进行计算处理,选取195〜225nm的光谱数据,根据Beer- Lambert定律:I1 (λ) = 1〇(λ) exp (-σ (λ) CL),σ (λ)为吸收截面,C为气体浓度,L为吸收长度,得到吸收度 [0045] 3) the computer 8 calculates the data signal processing, spectral data 195~225nm select, according to the law of Beer- Lambert: I1 (λ) = 1〇 (λ) exp (-σ (λ) CL), σ ( [lambda]) is the absorption cross section, C is the concentration of the gas, L is the length of the absorbent, absorption to give

Figure CN104280355BD00081

其中i表示气体组分;由于待测对象多为混合气体和颗粒的混合物,所以存在水蒸气的吸收、CCD的响应、米氏散射、瑞利散射因素的影响,因而吸收度分为快变(λ)和慢变(λ)两部分: Where i represents the gas component; mostly due to the object to be measured and the gas mixture was mixed particles, so that the presence of water vapor absorption, the impact response of the CCD Mie scattering, Rayleigh scattering factors and thus becomes faster absorption into ( [lambda]) and slowly varying ([lambda]) of two parts:

Figure CN104280355BD00082

[0049] 其中εκ、εΜ分别表示瑞利散射系数和米氏散射系数,V1是随波长快速变化的窄带吸收截面,〇lb是随波长缓慢变化的宽带吸收截面;对由195〜225nm的光谱数据计算得到的吸收度〇1(1)进行五阶多项式拟合,得到拟合系数&1、131、(31、(11、61、£1,吸收度慢变部分表示为: [0049] wherein εκ, εΜ represent Rayleigh scattering and Mie scattering coefficient coefficient, V1 is rapidly changing with wavelength narrowband absorption cross section, with a broad band of wavelengths 〇lb slowly varying absorption cross section; spectral data of 195~225nm calculated absorbance 〇1 (1) for fifth order polynomial fitting, fitting coefficients to obtain & amp; 1,131, (31, (11,61, £ 1, the absorbance of the slowly varying part is expressed as:

[0050] [0050]

Figure CN104280355BD00083

[0051] 差分吸收度 [0051] Differential absorbance

Figure CN104280355BD00084

,对具有准周期性规律的差分吸收度D71 (λ)进行傅里叶变换,得到二氧化硫气体的特征峰值 , Wherein the difference Fourier transform peak absorbance D71 (λ) has a quasi-periodic law, sulfur dioxide gas obtained

Figure CN104280355BD00085

[0052] 4)重复步骤2)、3),所不同的是在所述的气体吸收池4依次充入浓度为1500、2000、 2500、3000、3500、4000、4500、5000??111的二氧化硫气体,分别得到二氧化硫气体的特征峰值 [0052] 4) repeating steps 2), 3), except that in the gas absorption cell concentration of 4 successively charged 1500, 2000, 2500,3000,3500,4000,4500,5000 dioxide 111 ?? characterized in peak gas, sulfur dioxide gas respectively

Figure CN104280355BD00086

[0053] 5)用最小二乘法对二氧化硫气体的特征峰值巧(¾与二氧化硫的气体浓度Cs〇2进行线性拟合,得到拟合系数Hi1、m, [0053] 5) by the least square method wherein sulfur dioxide gas peak Qiao (¾ and sulfur dioxide gas concentration Cs〇2 linear fitting, fitting coefficients obtained Hi1, m,

Figure CN104280355BD00087

[0054] 6)重复步骤2)、3),所不同的是在所述的气体吸收池4依次充入浓度分别为2、4、6、 8、10、12、14、16、18、20ppm的氨气以及IOOOppm的二氧化硫混合气体,用最小二乘法对氨气的特征峰值#与氨气浓度Cmi3进行线性拟合,得到拟合系数m2、n2, [0054] 6) repeating steps 2), 3), except that in the gas absorption cell 4 concentrations were successively charged 2,4,6, 8,10,12,14,16,18,20ppm a mixed gas of sulfur dioxide and ammonia IOOOppm of peak # performed by the least squares method wherein the concentration of ammonia and ammonia Cmi3 linear fitting, fitting coefficients to obtain m2, n2,

Figure CN104280355BD00088

[0055] 7)重复步骤6),所不同的是二氧化硫的浓度依次换成1500、2000、2500、3000、 3500、4000、4500、5000??111,得到不同二氧化硫浓度下,氨气的特征峰值朽《13与氨气浓度£^3 线性拟合公式,1112与二氧化硫浓度满足三次函数关系,通过三次拟合得到拟合系数Pl、 P2、P3、P4, [0055] 7) Repeat step 6), except that the concentration of sulfur dioxide are sequentially replaced 1500,2000,2500,3000, 3500,4000,4500,5000 ?? 111, obtained at different concentrations of sulfur dioxide, ammonia Characteristic Peak rot "13 and the ammonia concentration linear fitting equation £ ^ 3, 1112 with the sulfur dioxide concentration satisfies cubic function, fitting coefficients obtained by fitting the three Pl, P2, P3, P4,

Figure CN104280355BD00089

12与二氧化硫浓度CS02满足线性关系,通过线性拟合得到系数Φ、Φ, And the sulfur dioxide concentration 12 CS02 satisfies a linear relationship, obtained coefficients Φ, Φ through linear fitting,

Figure CN104280355BD000810

[0056] 步骤二、测量:请参阅图5,图5是本发明所述方法的测量流程图。 [0056] Step two, measuring: Referring to FIG. 5, FIG. 5 is a flowchart showing the measuring method of the present invention.

[0057] 1)重复步骤一中的2)、3),所不同的是在所述的气体吸收池4充入待测氨气和二氧化硫混合气体,得到经参考气室氨气、待测氨气和二氧化硫混合气体吸收后的光强I2 (λ), 计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氮气参比气室和氨气、二氧化硫混合气体吸收的吸收度D2 (λ) [0057] 1) Repeat steps 2), 3), except that in the gas absorption cell charged under test 4 mixed gas of ammonia gas and sulfur dioxide, ammonia gas obtained after the reference gas chamber, measured ammonia after the mixed gas and sulfur dioxide gas absorption intensity I2 (λ), the computer data signal optical transmission spectrometer calculation processing is performed to obtain the absorption wavelength of 195~225nm reference gas chamber with nitrogen and ammonia, a mixed gas of sulfur dioxide absorbed D2 (λ)

Figure CN104280355BD00091

对由195〜225nm的光谱数据计算得到的吸收度D2 (λ)进行五阶多项式拟合 The obtained spectrum data calculated from the absorbance 195~225nm D2 (λ) for fifth order polynomial fitting

Figure CN104280355BD00092

€2,得到拟合系数32、62、02、(12、62、;^2,差分吸收度 2 €, fitting coefficients obtained 32,62,02, (12, 62,; ^ 2, the differential absorption

Figure CN104280355BD00093

,对具有准周期性规律的差分吸收度D'2 (λ)进行傅里叶变换,得到待测二氧化硫气体的特征峰值马〇2,通过下式计算二氧化硫气体浓:: , Quasi differential absorption of the periodicity of D'2 (λ) Fourier transform, wherein sulfur dioxide gas measured peak horse 〇2, calculated by the formula of concentrated sulfur dioxide gas ::

[0058] [0058]

Figure CN104280355BD00094

[0059] 2)重复步骤二中的1),所不同的是:转轮转动180°,切换到氮气参比气室301,得到待测氨气和二氧化硫混合气体吸收后的光强I3 (λ),计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氮气参比气室和氨气、二氧化硫混合气体吸收的吸收度 [0059] 2) two repeating steps 1), except that: the wheel is rotated 180 °, switching to a nitrogen reference gas chamber 301, after the test to obtain a mixed gas of ammonia gas and sulfur dioxide absorbed light intensity I3 (λ ), the computer data signal optical transmission spectrometer calculation processing is performed to obtain the absorption wavelength of 195~225nm reference gas chamber with nitrogen and ammonia, a mixed gas of sulfur dioxide absorbed

Figure CN104280355BD00095

,对由195〜225nm的光谱数据计算得到的吸收度D3 (λ)进行五阶多项式拟合: , To be calculated from the absorbance spectral data 195~225nm D3 (λ) for fifth order polynomial fitting:

Figure CN104280355BD00096

,得到拟合系数a3、b3、C3、d3、e3、f3, 差分吸收度DS (λ) =D3 (λ) -D〃3 (λ),对具有准周期性规律的差分吸收度DS (λ)进行傅里叶变换,得到氨气气体的特征峰值巧% _,通过下式计算氨气的浓度cWi To give fitting coefficients a3, b3, C3, d3, e3, f3, differential absorption of DS (λ) = D3 (λ) -D〃3 ([lambda]), differential absorption degree DS quasi periodic law ([lambda] ) Fourier transform, wherein the ammonia gas is _% peak Qiao, calculated by the concentration of ammonia cWi

[0060] [0060]

Figure CN104280355BD00097

[0061] 本发明所述检测装置对氨气和二氧化硫浓度测量的原理如下: [0061] The detecting means of the present invention to ammonia and sulfur dioxide concentration measurement principle is as follows:

[0062] 结合图2、3、4说明本发明的工作原理,紫外光源发出的紫外光被氨气和二氧化硫混合气体吸收后,在195〜225nm波段出现振荡吸收谱,这是由于氨气和二氧化硫共同吸收产生的,该波段二氧化硫两吸收峰间的间隔约为1.6〜1.8nm,氨气两吸收峰间的间隔约为3.6〜3.8nm。 [0062] described in conjunction with FIG. 2, 3, operation of the present invention, ultraviolet light is absorbed by the ultraviolet light emitted by the source of sulfur dioxide and a mixed gas of ammonia gas, oscillation occurs in the absorption spectrum of 195~225nm wavelength band, which is due to ammonia and sulfur dioxide common absorption generated, the spacing between the two bands of sulfur dioxide absorption peak of about 1.6~1.8nm, the interval between the two peaks is approximately ammonia 3.6~3.8nm. 因此我们可以通过紫外光在200nm附近波段的周期振荡吸收对其特征吸收光谱数据做快速傅里叶变换(FFT),因两种气体吸收谱线的周期不同,会出现不同的特征峰, 如图4所示。 Therefore, we can absorb ultraviolet light in the oscillation period of the characteristics in the vicinity of 200nm absorption band spectrum data to make a fast Fourier transform (an FFT), due to two different absorption lines of the gas cycle, there will be different characteristic peaks, in FIG. Fig. 且当一种气体浓度固定的时候,另外一种气体FFT的特征峰值与气体浓度呈良好的线性关系。 When the concentration of a gas is fixed and when the additional feature of a gas to the gas concentration peak of the FFT is a good linear relationship.

[0063] 本方法主要依据是Beer-Lambert定律: [0063] The present method is mainly based on Beer-Lambert law:

[0064] I (λ) =Ι〇(λ) exp (-〇(λ) CL) [0064] I (λ) = Ι〇 (λ) exp (-〇 (λ) CL)

[0065] 其中Io (λ)为背景光强,I (λ)为经过气体吸收之后的光强,σ (λ)为吸收截面,C为气体浓度,L为吸收长度。 [0065] where Io (λ) is the background light intensity, I (λ) is elapsed after the gas absorption intensity, σ (λ) is the absorption cross section, C is the concentration of the gas, L is the length of the absorbent.

[0066] 由于待测对象多为混合气体和颗粒的混合物,所以存在水蒸气的吸收、CCD的响应、米氏散射、瑞利散射等因素的影响,因而吸收截面分为两部分,一是随波长快速变化的窄带吸收截面,二是随波长缓慢变化的宽带吸收截面= ,所以对上式做如下修正: [0066] Since the object to be measured and the mixed gas is a mixture of multiple particles, the absorption of water vapor is present, affect the response of the CCD, Mie scattering, Rayleigh scattering and other factors, and thus the absorption cross section is divided into two parts, with rapid changes in the wavelength of the narrowband absorption cross section, the second is a slowly varying function of wavelength = broadband absorption cross section, so the correction formula as follows:

Figure CN104280355BD00098

[0070] 其中 [0070] in which

Figure CN104280355BD00101

[0071] Ιο'(λ)表示吸收光谱随波长的慢变部分,εκ、εΜ分别表示瑞利散射系数和米氏散射系数。 [0071] Ιο '(λ) represents the absorption wavelength with the slowly varying part of the spectrum, εκ, εΜ represent Rayleigh scattering coefficient and Mie scattering coefficient. 定义差分吸收度: Differential absorbance defined:

[0072] [0072]

Figure CN104280355BD00102

[0073] 未通待测混合气体,经过高浓度氨气之后的差分吸收度为: [0073] The mixed gas test does not pass through differential absorption of the ammonia concentration is high after:

[0074] [0074]

Figure CN104280355BD00103

[0075] 通入待测氨气与二氧化硫混合气体之后的差分吸收度为: [0075] After the differential absorption of ammonia gas and sulfur dioxide into the mixed gas to be measured is:

[0076] [0076]

Figure CN104280355BD00104

[0077] 其中,〇NH3、oSQ2分别为氨气和二氧化硫的吸收截面, [0077] wherein 〇NH3, oSQ2 are ammonia and sulfur dioxide absorption cross section,

Figure CN104280355BD00105

、Cs〇2分别为参比气室高浓度氨气、待测低浓度氨气和待测二氧化硫气体浓度。 , Respectively Cs〇2 reference gas chamber high concentration of ammonia, and the ammonia concentration measured low concentrations of sulfur dioxide gas test. 因氨气参比气室装有高浓度的氨气(1000〜2000ppm),而待测氨气浓度较低(0〜20ppm),S卩 Ammonia because ammonia reference gas chamber filled with high concentration (1000~2000ppm), while lower ammonia concentration tested (0~20ppm), S Jie

Figure CN104280355BD00106

,所以可忽略待测氨气浓度,得到二氧化硫的差分吸收度: , The measured ammonia concentration can be ignored, resulting differential absorption of sulfur dioxide:

[0078] [0078]

Figure CN104280355BD00107

[0079] 根据二氧化硫气体在固定氨气浓度下的FFT特征峰值与二氧化硫气体浓度呈线性关系而得出的拟合标定公式. [0079] FFT characteristic peaks at a fixed linear relationship between the ammonia concentration of sulfur dioxide gas and sulfur dioxide gas according to the concentration of the calibration equation derived fitting.

Figure CN104280355BD00108

计算得到二氧化硫的浓度,其中Csa2为待测SO2气体浓度,为二氧化硫气体FFT特征峰值,mi、如分别为拟合得到的斜率与截距。 Calculated concentration of sulfur dioxide, SO2 wherein Csa2 gas concentration is measured as a characteristic peak FFT sulfur dioxide gas, mi The, such as the slope and intercept were obtained by fitting. 切换氮气参比气室301,即已知二氧化硫气体浓度,在固定二氧化硫气体浓度下氨气的FFT特征峰值与氨气的浓度呈线性关系,拟合公式为 Nitrogen handover reference gas chamber 301, i.e., a known concentration of sulfur dioxide gas, sulfur dioxide gas concentration at a fixed concentration of ammonia and the peak FFT wherein ammonia is linear fitting formula

Figure CN104280355BD00109

其中Cnh3为待测NH3气体浓度,Fnh3为氨气FFT特征峰值,m2、n2分别为拟合得到的斜率与截距;通过大量数据计算发现氨气的FFT特征峰值与氨气浓度的线性关系式的斜率m2与二氧化硫浓度满足三次函数关系 Wherein the concentration of the test gas Cnh3 is NH3, Fnh3 characterized ammonia gas FFT peak, m2, n2 are obtained by fitting the slope and intercept; linear relationship was found ammonia and ammonia concentration peak FFT characterized by a large number of data calculation the slope m2 and meet three times a function of the concentration of sulfur dioxide

Figure CN104280355BD001010

,截距1!2与二氧化硫浓度满足线性关系 Intercept 1! 2 satisfy the linear relationship between the concentration of sulfur dioxide

Figure CN104280355BD001011

•其中口142 43^4、91、92为拟合系数。 • wherein the opening is 14,243 ^ 4,91,92 fitting coefficients. 即通过标定,当获得二氧化硫气体浓度时,便可计算得到氨气线性公式的斜率Hi2与截距n2,再根据氨气的特征峰值即可按照标定公式(N丨丨,=坩2厂_,十…计算得出M气的浓度。 That is, through calibration, it is obtained when the concentration of sulfur dioxide gas, ammonia gas can be calculated from the slope of the linear equation intercept Hi2 n2, then according to the calibration formula _ (N Shushu, crucible 2 = peak ammonia plant according to the characteristics, ten ... M calculated gas concentration.

Claims (1)

  1. 1.利用氨气和二氧化硫气体浓度的检测装置检测氨气和二氧化硫气体浓度的方法,该装置由紫外光源(1)、准直透镜(2)、转轮(3)、气体吸收池(4)、会聚透镜(5)、紫外光纤(6)、 光谱仪(7)和计算机(8)组成;沿所述的紫外光源(1)发出的紫外光依次是所述的准直透镜(2)、转轮(3)上的氮气参比气室(301)或氨气参比气室(302)、气体吸收池(4)、会聚透镜(5)、紫外光纤(6),该紫外光纤(6)的输出端连接光谱仪(7)的接收端,该光谱仪⑵的输出端接计算机(8)的输入端;其特征在于该方法包括如下步骤: 步骤一、标定: 1) 在所述的气体吸收池(4)充入氮气,将所述的氮气参比气室(301)通过转轮(3)置于光路中,启动所述的紫外光源(1)和计算机(8),紫外光源(1)发出紫外光经准直透镜(2)后变成平行光通过高浓度氮气参比气室(301),入射到气体吸收池⑷,从气体吸收池⑷出射的 1. The method of detection using ammonia and sulfur dioxide gas concentration of ammonia and sulfur dioxide gas concentration detection means by the ultraviolet light source (1), a collimating lens (2), the runner (3), a gas absorption cell (4) , converging lens (5), an ultraviolet optical fiber (6), a spectrometer (7) and a computer (8) the composition; ultraviolet light emitted along said ultraviolet light source (1) followed by said collimator lens (2), transfer wheel nitrogen reference gas chamber (301) or ammonia reference gas chamber (302) on the (3), a gas absorption cell (4), converging lens (5), an ultraviolet optical fiber (6), the UV fibers (6) connecting spectrometer (7) of the receiving end of the output terminal, the spectrometer ⑵ output end computer (8) is input; characterized in that the method comprises the following steps: step a, calibration: 1) the gas absorption cell (4) charged with nitrogen, the nitrogen reference gas chamber (301) in the optical path, activating the ultraviolet light source (1) and the computer (8), the ultraviolet light source (1) through a runner (3) after emits ultraviolet light by a collimator lens (2) into parallel light by a high concentration of nitrogen reference gas chamber (301) into the gas absorption cell ⑷, the gas absorption cell from exiting ⑷ 经会聚透镜⑶聚焦耦合进紫外光纤(6)输入到所述的光谱仪(7)的接收端,光谱仪(7) 输出的数据信号输入所述的计算机(8),计算机(8)通过软件采集得到背景光强Io (λ); 2) 在所述的气体吸收池(4)充入浓度为IOOOppm的二氧化硫气体,将所述的氨气参比气室(302)通过转轮⑶置于光路中,紫外光源⑴发出紫外光经准直透镜⑵后变成平行光通过高浓度氨气参比气室(302),入射到气体吸收池(4),从气体吸收池(4)出射的光经会聚透镜⑶聚焦耦合进紫外光纤(6)输入到所述的光谱仪⑵的接收端,光谱仪⑵输出的数据信号输入所述的计算机(8),计算机(8)通过软件采集得到气体吸收后的光强I1 (λ); 3) 计算机(8)对数据信号进行计算处理,选取195〜225nm的光谱数据,根据Beer-Lambert定律:I1 (λ) = 1〇(λ) exp (-σ (λ) CL),σ (λ)为吸收截面,C为气体浓度,L为吸收长度,得到吸收度 By a converging lens ⑶ focusing coupled into the UV fibers (6) into the spectrometer (7) of the receiving end, the spectrometer (7) a data signal input to the output of the computer (8), a computer (8) obtained by the software acquisition background light intensity Io (λ); 2) the gas absorption cell (4) is charged at a concentration of IOOOppm of sulfur dioxide gas, the ammonia reference gas chamber (302) by turning in the optical path ⑶ , ⑴ ultraviolet light source emits ultraviolet light after the collimator lens becomes parallel light by ⑵ high ammonia concentration reference gas chamber (302) into the gas absorption cell (4), the light from the gas through the absorption cell (4) emitted a converging lens ⑶ focusing coupled into the UV fibers (6) into the receiving end of the spectrometer ⑵, the data signal input of the spectrometer ⑵ output computer (8), a computer (8) of the light after gas absorption obtained by the software acquisition strong I1 (λ); 3) a computer (8) calculates the data signal processing, spectral data 195~225nm select, according to the Beer-Lambert law: I1 (λ) = 1〇 (λ) exp (-σ (λ) CL), σ (λ) is the absorption cross section, C is the concentration of the gas, L is the length of the absorbent, absorption to give
    Figure CN104280355BC00021
    7其中i表示气体组分;由于待测对象多为混合气体和颗粒的混合物,所以存在水蒸气的吸收、CCD的响应、米氏散射、瑞利散射因素的影响,因而吸收度分为差分吸收度D7 i (λ)和慢变(λ)两部分: 7 where i represents the gas component; since the object to be measured and the mixed gas is a mixture of multiple particles, there is absorption of water vapor, affect the response of the CCD Mie scattering, Rayleigh scattering factor, thus absorbance differential absorption into of D7 i (λ) and slowly varying ([lambda]) of two parts:
    Figure CN104280355BC00022
    其中εΚ、εΜ分别表示瑞利散射系数和米氏散射系数,〇\是随波长快速变化的窄带吸收截面,〇lb是随波长缓慢变化的宽带吸收截面;对由195〜225nm的光谱数据计算得到的吸收度以(λ)进行五阶多项式拟合,得到拟合系数^bhC1 J1,吸收度慢变部分表示为: D"i (λ) =aiA5+biA4+ciA3+diA2+eiA+fi, 差分吸收度(λ) =D1 (λ) -D% (λ),对具有准周期性规律的差分吸收度(λ)进行傅里叶变换,得到二氧化硫气体的特征峰值; 4) 重复步骤2)、3),所不同的是在所述的气体吸收池(4)依次充入浓度为1500、2000、 2500、3000、3500、4000、4500、500(^口111的二氧化硫气体,分别得到二氧化硫气体的特征峰值 Wherein εΚ, εΜ represent Rayleigh scattering and Mie scattering coefficient coefficient, square \ is rapidly changing with wavelength narrowband absorption cross section, 〇lb is slowly varying with wavelength broadband absorption cross section; Calculation of the spectrum data obtained in 195~225nm in absorbance ([lambda]) for fifth order polynomial fitting, fitting coefficients to obtain ^ bhC1 J1, the slowly varying part of the absorption is expressed as: D "i (λ) = aiA5 + biA4 + ciA3 + diA2 + eiA + fi, differential absorbance (λ) = D1 (λ) -D% (λ), difference Fourier transform on the periodicity of quasi absorbance ([lambda]), wherein the peak to give sulfur dioxide gas; 4) repeating steps 2), 3), except that in the gas absorption cell (4) are sequentially charged to a concentration of 1500, 2000, 2500,3000,3500,4000,4500,500 sulfur dioxide gas (the ^ port 111, respectively sulfur dioxide gas characteristic peak
    Figure CN104280355BC00023
    5) 用最小二乘法对二氧化硫气体的特征峰值与二氧化硫的气体浓度Ao2进行拟合, 得到拟合系数6) 重复步骤2)、3),所不同的是在所述的气体吸收池⑷充入浓度分别为2、4、6、8、10、 12、14、16、18、20ppm的氨气以及IOOOppm的二氧化硫混合气体,用最小二乘法对氨气的特征峰值巧%与氨气浓度cW3进行线性拟合,得到拟合系数m 2、η 2,所述的氨气浓度 5) by the least square method wherein sulfur dioxide gas and sulfur dioxide gas concentration peak Ao2 by curve fitting fitting coefficient 6) repeating steps 2), 3), except that in the gas absorption cell charged ⑷ concentrations respectively 2,4,6,8,10, 12,14,16,18,20ppm sulfur dioxide and ammonia in the mixed gas IOOOppm, characterized in ammonia by the least square method with peak Qiao% ammonia concentration cW3 linear fitting, fitting coefficients to obtain m 2, η 2, the ammonia concentration
    Figure CN104280355BC00031
    7) 重复步骤6),所不同的是二氧化硫的浓度依次换成1500、2000、2500、3000、3500、 4000、4500、5000ppm,得到不同二氧化硫浓度下的氨气的特征峰值巧啤与氨气浓度Cnh3拟合公式,所述的拟合系数肥与二氧化硫浓度cso。 7) Repeat step 6), except that the concentration of sulfur dioxide are sequentially replaced 1500,2000,2500,3000,3500, 4000,4500,5000ppm, ammonia to give specific peak at different concentrations of sulfur dioxide and ammonia concentration beer clever Cnh3 fitting formula, the fertilizer and the sulfur dioxide concentration fitting coefficient cso. 近似三次函数关系,通过三次拟合得到拟合系数Pl、P2、P3、P4 Cubic function approximation, cubic fit obtained by fitting coefficients Pl, P2, P3, P4
    Figure CN104280355BC00032
    .,所述的拟合系数Π2与二氧化硫浓度Cso。 ., The sulfur dioxide concentration and fitting coefficients Π2 Cso. 近似线性关系,通过拟合得到系数qi、q2,所述的拟合系数》2 =%Cs〇2 +% ; 步骤二、测量: 1) 重复步骤一中的2)、3),所不同的是在所述的气体吸收池(4)充入待测氨气和二氧化硫混合气体,得到经氨气参比气室、待测氨气和二氧化硫混合气体吸收后的光强I2 (λ),计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氨气参比气室和氨气、二氧化硫混合气体吸收的吸收度D2 (λ),D2 (λ) =DS (λ) +D〃2 (λ),对由195〜225nm的光谱数据计算得到的吸收度D2 (λ)进行五阶多项式拟合,D〃2 (λ) =a2f+b2A4+C2A3+d2A2+e2A+f2, 得到拟合系数32、&2、。 Approximate linear relationship, obtained by fitting coefficients qi, q2, fitting coefficients "a 2 =% +% Cs〇2; step two, measuring: 1) Repeat steps 2), 3), except that is measured in a mixed gas of ammonia gas and sulfur dioxide gas in the absorption cell (4) charged, obtained by the ammonia after the reference gas chamber, a mixed gas of sulfur dioxide and ammonia gas to be measured absorbs light intensity I2 (λ), the computer optical transmission spectrometer data signal is calculated to give a wavelength of the reference gas chamber via ammonia and ammonia 195~225nm, and a mixed gas of sulfur dioxide absorbed absorbance D2 (λ), D2 (λ) = DS (λ) + D〃2 ([lambda]), to be calculated from the absorbance spectral data 195~225nm D2 (λ) for fifth order polynomial fitting, D〃2 (λ) = a2f + b2A4 + C2A3 + d2A2 + e2A + f2, fitting coefficients to obtain 32, & amp; 2 ,. 2、(12、62、€2,差分吸收度〇/2〇〇=〇2〇〇-〇〃2〇〇,对具有准周期性规律的差分吸收度DS (λ)进行傅里叶变换,得到待测二氧化硫气体的特征峰值巧〇_,通过下式计算二氧化硫气体浓度cso:: 2, (12,62, € 2, differential absorption of square / 2〇〇 = 〇2〇〇-〇〃2〇〇, differential absorption DS (λ) has a quasi-periodic regular Fourier transform, characteristics measured to obtain a peak coincidence 〇_ sulfur dioxide gas, sulfur dioxide gas calculated by the concentration cso ::
    Figure CN104280355BC00033
    2) 重复步骤二中的1),所不同的是:转轮转动180°,切换到氮气参比气室(301),得到待测氨气和二氧化硫混合气体吸收后的光强I3 (λ),计算机对光谱仪传输的数据信号进行计算处理,得到波长为195〜225nm的经氮气参比气室和氨气、二氧化硫混合气体吸收的吸收度D3 (λ),D3 (λ) =D73 (λ) +D〃3 (λ),对由195〜225nm的光谱数据计算得到的吸收度D3㈨进行五阶多项式拟合,D〃3 (λ) =a3X5+b3X4+C3X3+d3X2+e3X+f 3,得到拟合系数a3、b3、C3、d3、Θ3、f 3,差分吸收度DS (λ) =D3 (λ) -D〃3 (λ),对具有准周期性规律的差分吸收度DS (λ)进行傅里叶变换,得到氨气气体的特征峰值11«13,通过下式计算氨气的浓度cNH,: 2) repeating steps 2 to 1), except that: the wheel is rotated 180 °, switching to a nitrogen reference gas chamber (301), to give the mixed gas of sulfur dioxide and ammonia gas to be measured absorbs light intensity I3 (λ) computer data signal optical transmission spectrometer was calculated to give a wavelength of 195~225nm reference gas chamber with nitrogen and ammonia, a mixed gas of sulfur dioxide absorbed absorbance D3 (λ), D3 (λ) = D73 (λ) D〃3 + ([lambda]), the absorption spectrum of the data obtained from the D3㈨ calculated 195~225nm fifth order polynomial fit is performed, D〃3 (λ) = a3X5 + b3X4 + C3X3 + d3X2 + e3X + f 3, to give fitting coefficients a3, b3, C3, d3, Θ3, f 3, differential absorption of DS (λ) = D3 (λ) -D〃3 (λ), differential absorption on a quasi-periodic DS having regular ([lambda]) Fourier transform, wherein the peak of the ammonia gas to give 11 «13, calculated by the concentration of ammonia cNH ,:
    Figure CN104280355BC00034
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