OT21 Optical Absorption Black Carbon Analyzer

Measurement principle:

By utilizing the light absorption properties of black carbon aerosols, the mass concentration of black carbon is obtained by measuring the absorption of specific wavelengths of light (370nm, 880nm) emitted by a light source by black carbon on an offline filter membrane.

Explanation: 880nm measurement is used for black carbon (or elemental carbon), while 370nm measurement is used for aromatic organic compounds, such as those produced by biomass combustion, such as smoke from wood combustion.

Instrument advantages:

*The absorption of other types of aerosol particles in the visible light range is less than 0.001 times that of elemental carbon. The black carbon analyzer can effectively eliminate other interfering factors and obtain accurate readings;

*Internal comparison: This optical absorption analysis instrument can obtain concentration values of BC or EC;

*Sensitivity: 1ATN unit, equivalent to a mass concentration of black carbon on the filter membrane of 0.06? g/cm2。 Under the conditions of a 24-hour sampling period, 16.7 L/min, and using a 47 mm sampling filter membrane, the sensitivity of BC is 0.075 μ g/m3;

*Measurement range: 0~125 ATN optical units, equivalent to a 24-hour sampling period, 16.7 L/min, under the condition of using a 47mm sampling filter membrane, the black carbon concentration range is 0~3.1?? g/m3。 The instrument can operate within a higher concentration range, but its linear range is easily affected;

*Reference membrane: Blank membrane analysis is used for 'zero' reference;

*Sampling membrane materials: quartz fiber filter membrane, Teflon filter membrane covered with borosilicate glass fiber, and Teflon filter membrane are recommended;

*Sample analysis area: OT21 uses 25 mm, 37 mm, and 47 mm filter membranes;

*Sample retention: OT21 analysis is non-destructive and can be followed by laboratory chemical analysis;

*Calibration: Use NIST reference filters for calibration;

*Internal control: All functions are controlled by embedded microprocessors. The program and operating parameters are stored in memory that is not easily modifiable;

*Data output: Digital data is transmitted from the RS232 (COM port) or USB port at the back;

*Display and interface: Two line display screen with menu selection confirmation key area;

*Regular maintenance: We recommend cleaning the optical analysis chamber once a year.

Technical parameters:

*Size and weight: 102 mm (H) x 270 mm (W) x 274 mm (D), 5.5 kg;

*Power supply: Use a transformer with 100~230 VAC, 50/60 Hz;

*Operating environment: indoor;

*Temperature: 0-40 ℃, no condensation;

*Vibration: The vibration of vehicles driving on highways has no effect on the instrument;

*Installation: It takes approximately 15 minutes from starting the power to obtaining valid data.

Application scope:

*Atmospheric aerosol black carbon monitoring;

*Monitoring of atmospheric radiation transmission;

*Monitoring of aromatic compounds with UV absorption;

*Monitoring of combustion emissions of carbon containing substances;

*Monitoring of combustion emissions from internal combustion engines;

*Other applications of black carbon analyzer:

※The black carbon analyzer calculates the concentration of black carbon aerosols based on the attenuation of transmitted light caused by black carbon aerosols on the sampling film, and therefore can also calculate the optical absorption coefficient of aerosols;

※The thermal optical carbon analysis method can also be applied to measure the elemental carbon (EC) aerosols on the sampling film, and the results can be compared with the optical method for measuring black carbon aerosols (BC) to establish a comparison of different measurement techniques.