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Air quality monitoring. Air and meteorological monitoring parameters. Environmental monitoring. Air quality monitoring. Classification of air pollutants Primary pollutants (emitted directly to the atmosphere)
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Air quality monitoring Air and meteorological monitoring parameters Environmental monitoring
Air quality monitoring • Classification of air pollutants • Primary pollutants (emitted directly to the atmosphere) • Secondary pollutants (formed by reactions involving primary pollutants and other constituents within the atmosphere) Environmental monitoring • Classification of sources of air pollutants • Stationary sources • Mobile sources • Sources • Natural sources • Anthropogenic sources • Urban sources
Air quality monitoring Primary air pollutants Environmental monitoring Secondary air pollutants are formed from sunlight that results in photochemical reactions of O2 with one or more of the primary air pollutants.
Air quality monitoring Legislation regarding the concentration limits Order no. 592/2002 revized by Order 448/2007 for establishing the limit values and the evaluation methods of several primary pollutants in the environmental air (imisii) Environmental monitoring *Added by Order 448/2007
Air quality monitoring Legislation regarding the concentration limits Order no. 592/2002 for establishing the limit values and the evaluation methods of several primary pollutants in the environmental air (imisii) Environmental monitoring Reference methods for concentration measurement
Air quality monitoring National Network for Air Quality Monitoring (RNMCA) www.calitateaer.ro
Air quality monitoring Romanian legislation regarding the concentration limits • Order no. 462/1993 regarding emissions from stationary sources (emisii) • Refers to emissions produced by • Stationary sources • Vehicles • Infrastructures designed to transportation • Burning installations • Fuel burning • Measurements are mandatory for the installation owner. • The results are to be registered and archived by the owner. • The limits are given according to the source. • If the limits are exceeded, the polluter pays. Environmental monitoring
Air quality monitoring Order no. 462/1993 Burner supplied with liquid fuel Environmental monitoring Burner supplied with solid fuel
Air quality monitoring Order no. 462/1993 Environmental monitoring Burner supplied with naturalgas
Air quality monitoring Methods and instrumentation • Passive sampling methods • Active sampling methods • Automatic methods • Remote optical - long path analyzers Environmental monitoring • Any instrument measures 3 types of values: • Instantaneous value • TWA (Time Weighted Average) • STEL (Short Term Exposure Limits)
Air quality monitoring Methods and instrumentation Gas measurement using spectroscopic methods Spectrophotometry is based on the interaction of the gas molecules with light. Environmental monitoring • Absorbtion techniques – it is measured the intensity of light after passing through a gaseous medium. Usually absorption is measured at several frequencies in order to avoid offests and interferences with other species. There are 4 principles: • Differential Optical Absorption Spectroscopy (DOAS) • Fourier Transform Infrared (FTIR) • Non-Dispersive Infrared (NDIR) • Tunable Laser Diode Absorption Spectroscopy(TLDAS)
Air quality monitoring Methods and instrumentation Gas measurement using spectroscopic methods Environmental monitoring • Emission techniques – excite molecules of the gas and then examine the light emitted as they return to their ground state.The signal is passed through a narrow-band filter and measured with a photomultiplier tube. • Flame photometry • Chemiluminescence • UV fluorescence
Air quality monitoring Measurement of carbon monoxide (CO) by IR photometry A = absorbance a = absorbtion coefficient b = path length C = concentration A = log(I/Io) = abC Beer’s law Environmental monitoring I0 I
Air quality monitoring Measurement of carbon monoxide (CO) Environmental monitoring
Air quality monitoring Measurement of carbon monoxide (CO) by IR photometry Environmental monitoring
Air quality monitoring Measurement of carbon monoxide (CO) by IR photometry Schematic of a NDIR head Environmental monitoring
Air quality monitoring Measurement of nitric oxides (NOx) by chemiluminescence Environmental monitoring Chemiluminescent reaction NO + O3 ==> NO2+ O2 + hv (0.6 – 3 μm)
Air quality monitoring Measurement of sulphur dioxide (SO2) by UV fluorescence Environmental monitoring Excitation S0 + hνex → S1 Fluorescence (emission) S1 → S0 + hνem + heat
Air quality monitoring Measurement of sulphur dioxide (SO2) by UV fluorescence Environmental monitoring
Air quality monitoring Measurement of sulphur dioxide (SO2) by UV fluorescence Teledyne 100E UV Fluorescence SO2 Analyzer Environmental monitoring Ranges: 0-50 ppb to 0-20,000 ppb full scale, user selectable or autoranging Units: ppb, ppm, µg/m3, mg/m3 Zero noise: < 0.2 ppb (RMS) Span noise: < 0.5% of reading (RMS) above 50 ppb Lower Detectable Limit (LDL): 0,4 ppb Linearity: 1% of full scale Precision: 0.5% of reading above 50 ppb Analog outputs: 10V, 5V, 1V, 0.1V, selectable Serial outputs: Serial Port 1: RS-232 (DB-9M) Serial Port 2: standard RS-232 or optional RS-485 (DB-9F), Ethernet
Air quality monitoring Gas chromatography Environmental monitoring Gas chromatography (video clip)
Air quality monitoring Measurement of Volatile Organic Compounds (VOC) Photo-Ionization Detector (PID) Environmental monitoring
Air quality monitoring Measurement of Volatile Organic Compounds (VOC) Photo-Ionization Detector (PID) Environmental monitoring
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Environmental monitoring Aerosol = particles + gas
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Gravimteric method Environmental monitoring
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Beta Attenuation Method Environmental monitoring
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Beta Attenuation Method Model: BAM-1020 EnviroTechnology Environmental monitoring Technical specifications Source Carbon-14 (C-14), < 3.7 MBq Measurement Range 0 to 1.0, 2.0, 3.0, 5.0, 10.0 mg/m3 0 to 100, 1,000, 2,000, 3,000, 5,000, 10,000 μg/m3 Minimum Detection Limit 6 μg/m3 (1/2 hour), 4 μg/m3 (1hour) 3 μg/m3 (3 hour), 1 μg/m3 (24-hour) Resolution 0.1 μg/m3 Precision ±2.0 μg/m3 < 80 μg/m3, 4-5 μg/m3 > 80 μg/m3 (24-hour average) Accuracy (for mass measurement) ± 5% using NIST-traceable mass foil set
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Optical method Environmental monitoring
Air quality monitoring Measurement of suspended particles (particulate matter – PM) Tapered Element Oscillating Microbalance (TEOM) Environmental monitoring
Air quality monitoring O2 O2 SnO2-x SnO2-x E eV în aer Gaz O2 SnO2-x SnO2-x E eV în prezenţa gazelor de reducere Measurement of gaseous pollutants using electrochemical sensors Environmental monitoring R = resistance A, α = constants C = gas concentration