A csapvíztől a glikolig, a környezeti levegőtől a földgázig : benzol és toluol koncentráció meghatározás széles dinamikus tartományban

Az előadásban egy olyan, fotoakusztikus detektáláson és kromatográfiás elválasztáson alapuló mérési mód kerül bemutatásra, amellyel folyadék és gázmintákban széles dinamikus tartományban lehet benzol és toluol koncentrációt meghatározni. A mérési módszert kipróbáltuk környezeti levegő, valamint vízmintákban. A laboratóriumi asztalon összeállított mérési elrendezésből egy komplett, automatikusan működő, terepen is használható mérőműszert fejlesztettünk. A műszert egy speciális földgázipari alkalmazáshoz optimalizáltuk; a földgázszárításban használt glikolban valamint a földgázban való mérésekre. Terepen is kipróbáltuk, a MÓL egyik telephelyén. We present here a measuring method which is combination of chromatography and photoacoustic spectroscopy. It can detect benzene and toluene concentration in gas and liquid samples over a wide dynamic range. The method was proved in ambient air and water samples. An automatic, field usable instrument was developed based on laboratory experiments. The instrument was optimized to a special application in gas industry. It can be applied to measure in natural gas and glycol used for dehydration of natural gas. Field measurements were carried out at a gas plant of MOL

Investigation of size distribution and spectral responses of diesel engine emitted carbonaceous particulate using multi waveleng photoacoustic spectroscopy (4λ-PAS) and single mobility particle sizer (SMPS)

This work discuss some results of the extended measurement campaign focussing the in-situ microphysical characterisation of the emitted diesel particulates of different fuel types at diferent operational condition of diesel engine. For measureemnt of the spectral repsonses and the size distribution of the diesel emission customised multi wavelength photoacoustic spectrometer and single commercially single mobility particle sizer were uesd. Basee on the size distribution data we experimentally demonstarte that at idle the emitted aerosol assembly have bimodal distribution in all type of fuel and working point of engine. We also demonstarte that the spectral responses of the diesel aerosol is characterisits for the type of fuel and the operational condition of engine. Using posterior temperature treatement we manifest that especially at idle the volatile fraction of the emitted aerosol can dominantly removed above 150C temeperature. Finally, we also experimentalla demonstarted that the biodiesel content of the diesel fuel even in its relatively small blending even in a relatively small (<7%) mixing ratio can significantly modify the climate and health relevant microphysical feature of the diesel emission

Source apportionment of carbonaceous chemical species to fossil fuel combustion, biomass burning and biogenic emissions by a coupled radiocarbon-levoglucosan marker method

An intensive aerosol measurement and sample collection campaign was conducted in central Budapest in a mild winter for 2 weeks. The online instruments included an FDMS-TEOM, RT-OC/EC analyser, DMPS, gas pollutant analysers and meteorological sensors. The aerosol samples were collected on quartz fibre filters by a low-volume sampler using the tandem filter method. Elemental carbon (EC), organic carbon (OC), levoglucosan, mannosan, galactosan, arabitol and mannitol were determined, and radiocarbon analysis was performed on the aerosol samples. Median atmospheric concentrations of EC, OC and PM2.5 mass were 0.97, 4.9 and 25 mu g m(-3), respectively. The EC and organic matter (1.6 x OC) accounted for 4.8 and 37 %, respectively, of the PM2.5 mass. Fossil fuel (FF) combustion represented 36% of the total carbon (TC = EC + OC) in the PM2.5 size fraction. Biomass burning (BB) was a major source (40 %) for the OC in the PM2.5 size fraction, and a substantial source (11 %) for the PM10 mass. We propose and apply here a novel, straightforward, coupled radiocarbon-levoglucosan marker method for source apportionment of the major carbonaceous chemical species. The contributions of EC and OC from FF combustion (ECFF and OCFF to the TC were 11.0 and 25 %, respectively, EC and OC from BB (ECBB and OCBB were responsible for 5.8 and 34 %, respectively, of the TC, while the OC from biogenic sources (OCBIO made up 24% of the TC. The overall relative uncertainty of the OCBIO and OCBB contributions was assessed to be up to 30 %, while the relative uncertainty for the other apportioned species is expected to be below 20 %. Evaluation of the apportioned atmospheric concentrations revealed some of their important properties and relationships among them. ECFF and OCFF were associated with different FF combustion sources. Most ECFF was emitted by vehicular road traffic, while the contribution of non-vehicular sources such as domestic and industrial heating or cooking using gas, oil or coal to OCFF was substantial. The mean contribution of BB to EC particles was smaller by a factor of approximately 2 than that of road traffic. The main formation processes of OCFF, OCBB and OCBIO from volatile organic compounds were jointly influenced by a common factor, which is most likely the atmospheric photochemistry, while primary organic emissions can also be important. Technological improvements and control measures for various BB appliances, together with efficient education and training of their users, in particular on the admissible fuel types, offer an important potential for improving the air quality in Budapest, and likely in other cities as well

Optical Properties, Chemical Composition and the Toxicological Potential of Urban Particulate Matter

This paper discusses the diurnal variation and the interdependences between the physical, chemical and toxicological characteristics of atmospheric carbonaceous particulate matter (CPM) and co-emitted gaseous components. Measurements were carried out at two different urban sites during a 2-month period. On-line measured parameters were optical absorption coefficients (OAC), total number concentration (TNC), mass concentration of CPM and the concentration of gaseous species (CO, NOx and BTEX). Off-line analyses were carried out on filters collected with 6-hour time resolution. The concentrations of elemental carbon (EC), organic carbon (OC), total carbon (TC), levoglucosan (LG) and polycyclic aromatic hydrocarbons (PAH) were determined. The ecotoxicity of CPM was assessed by the Vibrio Fischeri marine bioluminescence inhibition bioassay (ISO 21338:2010). We found (r > 0.498) positive and wavelength dependent correlation between the CPM related parameters based on optical response (OAC, AAE) and thermal stability (TC, EC, OC, OC/TC). We also revealed weak (r = 0.309) or moderate (r = 0.448) correlation between the AAE and the ecotoxicity data indicating that carbonaceous fraction of the ambient particulate matter has ecotoxicological impact. Based on the determined correlations, we propose the applicability of the AAE determined by multi wavelength photoacoustic measurements as a possible candidate for first-screening the toxicological impact of optically active carbonaceous ambient particulate matter. The strengths and the limitations of this methodology are both discussed here