There is a need for a robust and accurate technique to measure ammonia (NH3) emissions from animal feeding operations (AFOs) to obtain emission inventories and to develop abatement strategies. Two consecutive seasonal studies were conducted to measure NH3 emissions from an open-lot dairy in central Texas in July and December of 2005. Data including NH3 concentrations were collected and NH3 emission fluxes (EFls), emission rates (ERs), and emission factors (EFs) were calculated for the open-lot dairy. A protocol using flux chambers (FCs) was used to determine these NH3 emissions from the open-lot dairy. NH3 concentration measurements were made using chemiluminescence-based analyzers. The ground-level area sources (GLAS) including open lots (cows on earthen corrals), separated solids, primary and secondary lagoons, and milking parlors were sampled to estimate NH3 emissions. The seasonal NH3 EFs were 11.6 +/- 7.1 kg-NH3 yr(-1)head(-1) for the summer and 6.2 +/- 3.7 kg-NH3 yr(-1)head(-1) for the winter season. The estimated annual NH3 EF was 9.4 +/- 5.7 kg-NH3 yr(-1)head(-1) for this open-lot dairy. The estimated NH3 EF for winter was nearly 47% lower than summer EF. Primary and secondary lagoons (approximately 37) and open-lot corrals (approximately 63%) in summer, and open-lot corrals (approximately 95%) in winter were the highest contributors to NH3 emissions for the open-lot dairy. These EF estimates using the FC protocol and real-time analyzer were lower than many previously reported EFs estimated based on nitrogen mass balance and nitrogen content in manure. The difference between the overall emissions from each season was due to ambient temperature variations and loading rates of manure on GLAS. There was spatial variation of NH3 emission from the open-lot earthen corrals due to variable animal density within feeding and shaded and dry divisions of the open lot. This spatial variability was attributed to dispirit manure loading within these areas.
Studies show that agricultural and animal feeding operations (AFOs) contribute a considerable amount of ammonia (NH3) to the atmosphere. Agricultural NH3 emissions are recognized as an important air quality issue. Biological decomposition of manure from dairy operations results in emissions of NH3 and other gases. There is a need to determine NH3 emission factors (EFs) to compile annual NH3 inventories. NH3 emissions should be estimated from different ground-level area sources (GLAS) including open-lots (cows on earthen corrals), free-stalls (cows in barns), manure composting sites, primary and secondary lagoons, separated solids, and milking parlors. A protocol using flux chambers was used to determine NH3 EFs from different GLAS of a free-stall dairy in central Texas. Data including NH3 emissions from GLAS were collected during winter and summer seasons. NH3 concentration measurements were made using chemiluminescence-based analyzers. The EFs for the free-stall dairy were estimated as 11 +/- 4.9 (confidence interval [CI]) kg-NH3 x yr(-1) x head(-1) for summer and 4.7 +/- 4.9 kg-NH3 x yr(-1) x head(-1) for winter. The estimated annual NH3 EF was 8.4 +/- 4.9 kg-NH3 x yr(-1) head(-1) for this free-stall dairy. This seasonal difference was attributed to temperature, loading rate of dairy waste, and manure bacterial activity of GLAS. In winter, composted manure and free-stalls contributed nearly 77% of the total NH3 emissions for the dairy; however, in summer, two lagoons at the dairy contributed 65% of the overall NH3 emissions.
Her geçen gün artan nüfusla birlikte oluşan hızlı ve düzensiz şehirleşme çevresel gürültü sorununu da beraberinde getirmektedir. Öyle ki, Çevresel Gürültünün Değerlendirilmesi ve Yönetimi Yönetmeliği gereğince "eğitim kurumları" gürültü açısından en hassas mekânlardan biri olarak ifade edilmektedir. Bu nedenle, yaklaşık 20.000 kişinin (öğrenci ve personel) gün boyu fiilen bulunduğu Balıkesir Üniversitesi Çağış kampüs ortamının gün içinde maruz kaldığı gürültü seviyelerine ait gürültü haritalarının oluşturulması amaç edinilmiştir. Balıkesir Üniversitesi bünyesinde ilk defa yapılacak olan bu çalışma ile kampüs alanını içerisinde ki hassas noktalar olan fakülteler ve üniversite araştırma hastanesinin maruz kaldığı gürültü kirliliğinin temel kaynakları, incelenen mekânlara ait sabah ve akşam gürültü seviyeleri analiz edilmiş olup elde edilen sonuç ve çözüm önerileri çalışmamızda sunulmuştur. Çağış Kampüs'ünde en yüksek gürültü seviyelerinin ölçüldüğü yerler (Leq); İktisadi ve İdari Bilimler Fakültesi (İBF) öğrenci kantini 67,3 dB(A), Fen Edebiyat Fakültesi (FEF) öğrenci kantini 66,1 dB(A) gibi sosyal amaçlı ortak kullanım alanlarında gürültü aşımı gözlemlenmiştir. Mühendislik ve Mimarlık fakültesi ve Meslek Yüksek Okulunda sınır aşımı 65 dB(A) olduğu görülmüştür. Ayrıca, Balıkesir Üniversitesi araştırma hastanesi, modellenmiş sonuçları incelendiğinde 60,2 dB(A) ve 62,6 dB(A)'lık bir gürültü kirliliğine maruz kaldığı ve yasal sınırı aşmadığı gözlemlenmiştir.
Controlled bench-scale laboratory experiments were conducted to evaluate the recovery of ammonia (NH 3 ) and hydrogen sulfide (H 2 S) from dynamic isolation flux chambers. H 2 S (80 -4000 ppb) and NH 3 (5000 -40,000 ppb) samples were diffused through the flux chamber to simulate ground level area source emissions while measuring the inlet and outlet flux chamber concentrations simultaneously. Results showed that the recovery of H 2 S during a 30-min sampling time was almost complete for concentrations Ͼ2000 ppb. At the lowest concentration of 80 ppb, 92.55% of the H 2 S could be recovered during the given sampling period. NH 3 emissions exhibited similar behavior between concentrations of 5000 -40,000 ppb.Within the 30-min sampling period, 92.62% of the 5000-ppb NH 3 sample could be recovered. Complete recovery was achieved for concentrations Ͼ40,000 ppb. Predictive equations were developed for gas adsorption. From these equations, the maximum difference between chamber inlet and outlet concentrations of NH 3 or H 2 S was predicted to be 7.5% at the lowest concentration used for either gas.In the calculation of emission factors for NH 3 and H 2 S, no adsorption correction factor is recommended for concentrations Ͼ37,500 ppb and 2100 ppb for NH 3 and H 2 S, respectively. The reported differences in outlet and inlet concentration above these ranges are outside the fullscale sensitivity of the gas sensing equipment. The use of 46 -90 m of Teflon tubing with the flux chambers has apparently no effect on gas adsorption, because recovery was completed almost instantaneously at the beginning of the tests.
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