1 INDUSTRIAL MEASUREMENTS USING FTIR GAS ANALYZER Brief introduction, thoughts and experiences
MOTIVATION FOR EMISSION MEASUREMENTS 2 Condition of environment Air quality Emission studies Dispersion models RESEARCH LEGISLATION ABATEMENT Control policies Air quality control Safety Environmental permission Control of cleaning technologies Process operation Maintenance Optimization Warranty
EMISSION COMPOUNDS 3 Sulfur dioxide (SO 2 ) Nitrogen oxides (NOx) Particulate matter (PM2.5 & PM10) Heavy metals Polycyclic aromatic hydrocarbons (PAHs) Volatile organic compounds (VOCs) Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) CO 2 & CO
4 AIR POLLUTION MEASUREMENTS Air quality assessment (environmental authorities) Measuring directly from emission source (industrial measurements) In-situ continuous monitoring Process control, data acquisition Occasional on-site reference measurements Emission limits, comparison from continuous monitoring Standards Accredited measurer
5 STANDARD Defines the equipment, conditions, methods and actions to be conducted during measurements Crucial in order to have comparable results Ensures the work quality and repeatability of results SFS, CEN, ISO, EPA etc.
6 ACCREDITATION Process resulting in a certification of competency, authority or credibility by a specific organization Proofs that the measurer fulfills all the requirements and is able to do the job properly!
TO CONSIDER BEFORE MEASURING 7 Variety of things to take into account before, during, and after the measurements!! For example: Selection of sample probe placement Number of measuring points Proper connectors Used materials (e.g. inertness) Desired outcome Surrounding conditions Disturbing compounds Calibration Repeatability and linearity ANALYSIS OUTCOME Quantitative Qualitative Quantitative & qualitative Analysis results: VOC content in mg/m 3 548 Analysis results: VOC content in mg/m 3 benzene 53 benzo(a)pyrene 28 butadiene 12 1,2-dichlorethane 108 phenol 8 pyrene 98 1,1,2,2- tetrachloroethane 352 sum 659
8 MEASURING TECHNIQUES Continuous methods for on-site measurements (in situ) e.g. portable devices Gasmet Technologies Sample extraction methods to collect sample in a container in order to perform analysis in the laboratory Remote sensors
INFRARED SPECTROSCOPY Molecules absorb IR light at specific frequencies characteristic of their structure unique fingerprint quantitative and qualitative detection Reference spectrum library in which the sample gas spectra are compared Cannot detect homonucleus molecules such as H 2, O 2, or N 2 advantage if we want to measure air pollutant concentrations Non-dispersive and dispersive 9 TYPICAL ABSORPTION BANDS http://upload.wikimedia.org/wikipedia/en/6/6f/ir_summary_version_2.gif
ON-SITE FTIR GAS ANALYZER Non-destructive Real-time data Applicable in moist conditions Recorded spectra can be reanalyzed Gasmet TM DX4000 FTIR Gas Analyzer 10 Multicomponent measurement capability (up to 50) Quantitative and qualitative detection reliably above levels of 2 ppmv typically set to measure H 2 O, CO 2, CO, NO, NO 2, N 2 O, SO 2, NH 3, CH 4, HCl, HF and different VOCs Common applications: stack emission measurements, industrial monitoring
CASE EXAMPLE VOC ABATEMENT 11 Collaboration with local chemical plant Catalytic oxidizer in use for VOC emission treatment DATA FOR: Environmental permission Annual verification to meet the strict regulations of the VOC directive Process control operating conditions, maintenance, optimization, warranty Input Catalytic Oxidizer Output
CASE EXAMPLE LANDFILL SITE 12 A preliminary test to check if FTIR is a suitable technique for measuring ambient low-concentrated odorous gases Testing at many locations Directly from the stack Plastic bucket used to avoid immediate dilution to ambient air Ambient air
CASE EXAMPLE LANDFILL SITE 13 Directly from stack: Methane 10 to 18 [vol-%] CO 2 4 to 7 [vol-%] H 2 O 0 to 1 [vol-%] Ambient air: Analysis challenging due to relatively high methane concentration interference and overlapping Calibration concentrations exceeded Methane 3 to 7 [ppm] CO 2 0.05 [vol-%] H 2 O 0 to 1 [vol-%]
EXAMPLE LIBRARY 14
SAMPLE COMPARED TO REFERENCE 15 http://upload.wikimedia.org/wikipedia/en/6/6f/ir_summary_version_2.gif Sample spectrum Reference spectrum CH 4 calibrated up to 2000 ppm Indicative analysis result 9.9 vol-% unreliable since response is non-linear
REFERENCES & ANALYSIS AREAS / BUTYRIC ACID 10 vol-% of water 2000 ppm of methane 16 50 ppm of butyric acid
REFERENCES & ANALYSIS AREAS / BUTYRIC ACID AS A RESULT 17
SOME THOUGHTS 18 FTIR gas analyzer is a multi-purpose equipment Simultaneous measurement of organic and inorganic compounds from hot, wet and corrosive gas sources Identification of unknown sample matrix Low detection limits For example excessive water or carbon dioxide in the sample affects the spectra interpretation unreliable results Good reference gas library important Some idea of the compounds in the gas sample is very beneficial
19 Thank you!