Local air quality impacts due to downwash around thermal power plants: Numerical simulations of the effect of building orientation

One of the primary adverse environmental impacts associated with power generation facilities and in particular thermal power plants is local air quality. When these plants are operated at inland areas the dry type cooling towers used may significantly increase ambient concentrations of air pollutants due to the building downwash effect. When one or more buildings in the vicinity of a point source interrupt wind flow, an area of turbulence known as a building wake is created. Pollutants emitted from relatively low level sources can be caught in this turbulence affecting their dispersion. In spite of the fact that natural gas-fired combined-cycle power plants have lower air emission levels compared to other power plants using alternative fossil fuel, they can still create significant local air pollution problems. In this paper, local air quality impacts of a natural gas-fired combined-cycle power plant located in a coastal area are compared with those of another natural gas-fired combined-cycle power plant having identical air emissions but located in an inland area taking into account differences in topography and meteorology. Additionally, a series of scenarios for the inland site have been envisaged to illustrate the importance of plant lay-out configurations paying particular attention to the building downwash effect. Model results showed that different geometrical configurations of the stacks and cooling towers will cause remarkable differences in ambient air pollutant concentrations; thus it is concluded that when selecting a plant site, a detailed site-specific investigation should be conducted in order to achieve the least possible ambient air pollution concentrations with the given emissions

İzmir Aliağa endüstri bölgesinde hava kirliliğine neden olan organik ve inorganik kirleticilerin düzeylerinin, kaynaklarının ve sağlık etkilerinin belirlenmesi

TÜBİTAK ÇAYDAG01.07.200

Kocaeli’de evlerde, ofislerde ve okullarda iç ortam hava kalitesinin belirlenmesi

TÜBİTAK ÇAYDAG01.01.2008Bu çalışmada, Kocaeli’de farklı bölgelerde ve farklı mikroçevrelerde (ev, okul, ofis), iç ve dış ortamda yapılan örneklemeler ile aktif ve pasif örnekleme ve ölçüm teknikleri kullanılarak 2 farklı partikül fraksiyonunda (PM2.5 ve PM10) 16 ağır metal (Al, As, Ca, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, S, Si, Ti, V ve Zn), uçucu organik bileşikler (UOB’ler), SO2, NO2 ve O3 konsantrasyonları belirlenmiştir. Ayrıca, iç ortamda ölçülen konsantrasyonlarla maruziyet arasındaki ilişkiyi kurabilmek için, kişisel örnekleyiciler kullanılarak kişisel maruziyet düzeyleri de belirlenmiştir. NO2 için İç Ortam/Dış Ortam konsantrasyon oranlarının evlerde her 2 mevsimde de okullar ve ofislere nazaran yüksek bulunması evlerin iç ortamlarında NO2 kirletici kaynaklarının ofis ve okullara oranla daha baskın olduğu göstermektedir. İç Ortam/Dış Ortam oranlarının 1’in çok altında bulunması O3 ve SO2’in dış ortam kaynaklı bir kirletici olduğunu ve iç ortamlarda önemli bir kaynağının bulunmadığını göstermektedir. PM2.5 fraksiyonundaki toprak kaynaklı elementlerin iç ve dış ortam konsantrasyonlarının yüksek düzeylerde bulunması bu elementlerin iç ortamlara taşınımının yüksek olduğunu göstermektedir. PM2.5 kişisel maruziyet düzeylerinin As, S, V, Cu ve Cr gibi yanma kaynaklı elementler için iç ortam maruziyet düzeylerinden 2–6 kat daha yüksek olması ve bazı mevsimsel farklılıklar bulunmasına rağmen İç Ortam/Dış Ortam oranlarının genellikle 0.3–0.7 aralığında bulunması gözlenen yüksek kişisel maruziyet düzeylerinde dış ortamların etkisini göstermektedir. PM10 partikül fraksiyonunda belirlenen ağır metallerin büyük bir bölümü için İç Ortam/Dış Ortam oranlarının 1’den küçük bulunması dış ortam kirletici kaynaklarının iç ortam kirletici kaynaklarına daha baskın olduğunu göstermektedir. En yüksek UOB kirlilik düzeylerine örneklenen kişilerde rastlanırken bunu iç ortam ve dış ortam UOB kirlilik düzeyleri takip etmiştir. Her 2 mevsimde de toluen ev, ofis ve okullardaki UOB kirlilik düzeylerine en çok katkıda bulunan bileşik olurken onu etilbenzen, m,p-ksilen, stiren, nonan, hegzan, benzen, o-ksilen ve heptan bileşikleri takip etmektedir. Kentsel alanlarda elde edilen toplam UOB konsantrasyonlarının endüstriyel alanlarda elde edilen değerlerle uyum içinde bulunmuştur. Trafiğin belirteci olan bileşikler (BTEX, 1,2,4-trimetilbenzen) kentsel alanlarda yüksek bulunurken petrokimyanın belirteci olan hexane ve heptane bileşikleri endüstrinin yoğun olduğu alanlarda yüksek bulunmuştur. Ayrıca kentsel ve endüstriyel alanlarda elde edilen UOB konsantrasyonlarının sanayii ve trafikten uzak alanlarda elde edilen konsantrasyonlardan yüksek olması trafik ve sanayiinin tesbit edilen UOBlere olan katkısının ne kadar yüksek olduğunu göstermektedir. İç ortam, dış ortam ve kişisel maruziyet kirlilik düzeylerine etki ederek hava kalitesine olumsuz yönde katkıda bulunan kirletici kaynakların belirlenmesi amacıyla Pozitif Matris Faktörizasyonu (PMF) reseptör modelleme tekniği kullanılmıştır. PMF modellemesi, korelasyon analizi, iç ortam/dış ortam oranları, mikroçevre karakteristikleri, anketler ve zaman aktivite çizelgeleri incelenen kirleticilerin en önemli emisyon kaynaklarının endüstri, trafik ve sigara kullanımı olduğunu göstermektedir. İç ortam, dış ortam ve kişisel maruziyet düzeylerinin dünyanın diğer bölgelerinde yapılan çalışmalarda raporlanan düzeyler ile kıyaslanabilir olduğu bulunmuştur. Kişisel maruziyet konsantrasyonları kullanılarak çalışmada incelenen inorganik ve organik kirleticilerden kaynaklanan sağlık riski değerlendirmesi yapılmıştır. Ev, ofis ve okullarda örneklenen kişiler için hesaplanan “Toplam Kanser Riski” ve “Toplam Tehlike İndeksi” değerleri hem ortalama konsantrasyonlar hem de en kötü senaryo göz önüne alınarak incelendiğinde en yüksek risk altında bulunan kişilerin ev hanımları olduğu bunları öğretmenler ve ofis çalışanlarının takip ettiği söylenebilir. Değerlendirme kentsel, endüstriyel, endüstri ve trafikten uzak alanlar için yapıldığında her 3 alanda da yaşayan kişilerin birbirine yakın ve yüksek kanser riski taşıdıkları söylenebilir. Aynı değerlendirme sigara kullanan ve kullanmayan kişiler için yapıldığında sigara kullanan kişilerin kullanmayanlara nazaran yaklaşık %50 daha fazla kanser riski taşıdıkları gözlenmiştir.In this study, indoor and outdoor environment samples were taken from different regions and microenvironments (home, school, office) in Kocaeli. Through active and passive sampling and measurement techniques, 16 heavy metals (Al, As, Ca, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, S, Si, Ti, V and Zn) at 2 different particle fractions (PM2.5 and PM10), volatile organic compounds (VOCs), and SO2, NO2 and O3 concentrations were determined. Moreover, in an effort to establish the relationship between exposure and the indoor concentrations measured, personal samplers were used to determine personal exposure levels. Indoor/outdoor concentration ratios for NO2 were higher in homes than in schools or offices in both summer and winter, which shows that sources of NO2 pollutants in indoor environments of homes are more dominant than those found in offices or schools. The indoor/outdoor ratios were far below 1, indicating that O3 and SO2 are pollutants originating from outdoor environments and that they do not have significant sources in indoor environments. The presence of high levels of indoor and outdoor concentrations of crustal elements at PM2.5 fractions indicates that these elements are transported into indoor environments at high levels. PM2.5 personal exposure levels were 2–6 times higher than indoor levels for combustion-related elements such as As, S, V, Cu and Cr, and although there were some seasonal differences, the indoor/outdoor environment ratios generally ranged between 0.3–0.7 and indicated the effect of outdoor environments on the observed high personal exposure levels. The indoor/outdoor ratios for a major portion of the determined heavy metals at PM10 particle fractions were smaller than 1, showing that outdoor pollutants are more dominant than indoor pollutants. The highest VOC pollution levels were encountered in individuals in the sample, and this was followed by VOC pollution levels in indoor and outdoor environments. In both seasons, toluene levels were the highest pollutants for homes, offices and schools, followed by ethylbenzene, m/p-xylene, styrene, nonane, hexane, benzene, o-xylene and heptane. Total VOC concentrations obtained from urban areas were consistent with values obtained from industrial areas. Components that are indicators of traffic (BTEX, 1,2,4-trimethylbenzene) were measured at high levels in urban areas, while hexane and heptane components, which are indicators of petrochemistry, were recorded at high levels in high- industry areas. Moreover, VOC concentrations obtained from urban and industrial areas were higher than concentrations found in areas far from industry and traffic, which demonstrates the high contribution of traffic and industry to measured VOCs. This study investigated the summer and winter concentrations of selected pollutants and the relationship between indoor and outdoor environments. In order to determine pollutant sources that negatively contribute to air quality by affecting the degree of indoor, outdoor and personal exposures, the Positive Matrix Factorization (PMF) receptor modeling technique was used, which is a multivariate statistical analysis method. PMF, correlation analyses, indoor/outdoor ratios, microenvironment characteristics, responses to questionnaires, and time activity information suggested that industry, traffic and smoking represent the main emission sources of pollutants investigated. Indoor, outdoor and personal exposure concentration values were compared to values measured in different parts of the world, thereby evaluating consistency with the observed pollution level. Based on personal exposure concentrations, an assessment was conducted concerning the health risks associated with the inorganic and organic pollutants investigated in this study. When the calculated values for “Total Health Risk” and “Total Hazard Index” for people sampled in homes, offices and schools were examined by considering both the average concentrations and the worst scenarios, it was revealed that housewives are at the highest risk, followed by teachers and office workers. An examination of urban, industrial and far from urban, industrial and traffic areas revealed that people living in all of these three areas are subjected to high cancer risks, which are at similar levels. When the same evaluation was carried out for smokers and non-smokers, it was observed that smokers have a 50% higher risk of cancer compared to non-smokers

Uçucu organik bileşikler için pasif örnekleme tüplerinin tutma sabitlerinin belirlenmesi

TÜBİTAK ÇAYDAG15.08.200

Exposure of school children to Pb and Zn in an industrialized city of Turkey

Blood lead and serum zinc concentrations of school children were determined in Bursa and in a small village nearby. The geometric means of Pb were 4.78 mug/dL, both for the village and city center. Geometric means of zinc were 78.8 mug/dL, and 71.6 mug/dL for the village and city center, respectively. About 8% of the total population had blood lead levels higher than 10 mug/dL, and 28% a serum zinc concentration less than 70 mug/dL, which is below reference concentration. Bivariate analysis indicated a relation between blood Pb, sex of the children and time spent outdoors

Sampling and analysis of gaseous pollutants and related particulate matter in a Mediterranean site: Antalya-Turkey

Gas phase-pollutants, nitric acid (HNO3), sulfur dioxide (SO2), ammonia (NH3) and particulate matter, were collected simultaneously for six months from the Eastern Mediterranean atmosphere (Kucuk Calticak, Antalya) using a "filter pack" system developed in our laboratory. This system is a combination of chemically treated filters for the collection of gaseous ammonia and sulfur dioxide, and Teflon and nylon filters for the collection of particulate matter and gaseous nitric acid, respectively. After pre-treatment, Teflon, nylon and the treated filters were analyzed by ion chromatography (IC) for major ionic species: SO42-, NO3- and Cl-, and by colorimetry for NH4(+) ion. Comparison of the SRM (Standard Reference Material) results with measured concentrations showed a good precision for the IC analyses: 3%, 1% and 2% for Cl-, NO3- and SO42- ions, respectively. Most of the measured parameters were log-normally distributed. Chloride ion had the highest. (4.30 hg m(-3)) and HNO3 had the lowest (0.42 mug m(-3)) concentrations. Total acidity-in the Eastern Mediterranean is controlled by 47.7% HNO3 and 52.8% by H2SO4. Ammonium, nss-SO42- (non-sea salt sulfate) and NO3- did not show a strong correlation, (r(2)=0.4), which means that ammonia is not the major neutralizing species in the Eastern Mediterranean atmosphere

Rain water chemistry in Ankara, Turkey

Samples of rain water were collected in Ankara for the period between September 1989 and May 1990, by using wet-only sampler. Concentrations of major cations (H+, Na+, K+, Ca2+ and NH4+) and major anions (Cl-, NO3- and SO42-) were determined for the first time in Turkey. The rain water was not acidic owing to high concentrations of alkaline soil particles in the atmosphere. However, the concentrations of acid forming ions, such as SO42- and NO3-, were higher than the concentrations expected in a typical urban atmosphere. Most of the SO42- in rain water was in the form of CaSO4. Rain-aerosol coupling were examined by simultaneous sampling of aerosols with rain. The ions most efficiently scavenged from the atmosphere were found to be SO42- and Ca2+. (C) 1996 Elsevier Science Lt

The use of nuclear techniques in source apportionment studies, exemplified by recent studies in Turkey

Nuclear analytical methods are very important atmospheric tools as they provide multielement data, which is essential for receptor modeling. In this study, the application of receptor modeling is discussed on rural data to determine source regions affecting chemical composition of aerosols in the Eastern Mediterranean. The factor analysis revealed 4 sources, two of which represent anthropogenic component in aerosol mass. The source regions that determine the composition of particles is investigated using trajectory statistics

Evaluation of adsorbents with passive sampling and their analytical methods to determine volatile organic compounds emitted from vehicular exhaust

In order to accurate and precise determination of Volatile Organic Compounds (VOCs) from vehicular emissions were developed method including a) adsorption of VOCs on different adsorbents followed by thermal desorption and gas chromatography (GC) with flame ionization detector (FID) quantification, b) validation of the sampling and analytical method. The adsorption efficiency of Tenax and Chromosorb 106 adsorbents were eveluated for 104 VOCs to select of adequate sorbent for passive sampling. Since most of the anthropogenic VOCs emitted from urban location are associated with the vehicle experiments were performed near road side. The results obtained showed the both the adsorbents almost same efficieny for selected VOCs emitted from vehicular exhaust. The VOC levels measured in this study were comparable with European cities and lower than Asian cities. The differences of VOC levels measured with different cities are due to traffic composition of the cities and their characteristics of fuel