• Journal of Korean Society for Atmospheric Environment
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• 제23권E2호
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• pp.47-56
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• 2007

Among all the nitrogen species present in the atmosphere, ammonia forms a considerable portion along with the nitrogen oxides. The major sources of atmospheric ammonia are animal feedlot operations including emission from excreta of domestic animals and agricultural activities, followed by emission from synthetic fertilizers, biomass burning and to some lesser extent, fossil fuel combustion. Ammonia emission factor, expressed as the weight of ammonia per unit weight, volume, or duration of the activity emitting it, is generally used in developing emission estimates for emission inventories. The factors determining ammonia loss from soil or from manures are the temperature, pH, humidity, precipitation and the velocity of wind above it.

• 한국유기농업학회지
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• 제8권2호
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• pp.89-96
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• 2000

To reduce loss of nitrogen and generation of ammonia gas during composting, poultry manure and sawdust were mixed at the equivalent ratio and calcium chloride, fused superphosphate and vermiculite were added. Ammonia and sulfurous gas during composting, and NH4-N and NO3-N contents of composts were periodically measured. With the treatments of 0.5∼3% calcium chloride and 3% fused superphosphate, ammonia and sulfurous gas during composting significantly decreased, and especially generation of gases sharply reduced and a increase of calcium chlorde. Extractable NH4-N content in composts treasted with calcium chloride and fused superphosphate were high but extractable NO3-N markedly decreased. In conclusion, the results suggest that it is necessary the additon of 1∼3% calcium chloride or 3% fused superphosphate to reduce loss of nirogen and generation of offensive odor during composting of poultry manure mixed with sawdust.

• 한국염색가공학회지
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• 제7권3호
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• pp.44-52
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• 1995

Cotton and cellulosic other fabrics, such as rayon, polynosic, and linen were treated with liquid ammonia, and then were treated with cellulase after or before dyeing, as well as in the presence of dye. Dyeing was carried out with C. I. Direct Blue 1 at 5$0^{\circ}C$, for 6hr in the case of rayon, and 24hr in the case of cotton, polynosic, and linen. The optimum condition of cellulase was at 55$^{\circ}C$, pH 4~5. Weight loss of fabrics were increased by the liquid ammonia treatment and it was predominant when they were treated with cellulase alone and in the presence of dye. Changes of color strength of the cotton, polynosic, and linen were increased by liquid ammonia treatment compare with untreatment. Especially, in the presence of dye, K/S value of the liquid ammonia-treated fabrics were nearly the smae as untreated.

• 유기물자원화
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• 제8권3호
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• pp.81-88
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• 2000

음식쓰레기, 슬러지 등과 같이 C/N비가 낮은 폐기물을 호기성으로 퇴비화하는 경우 질소 성분이 많이 손실될 수 있으며, 이는 비료성분의 손실, 악취를 비롯한 환경오염 발생 등을 유발할 수 있다. 본 연구에서는 퇴비화 공정에서 질소성 물질의 보존방법을 도출하기 위한 기초 연구로 음식쓰레기를 실험실 규모로 퇴비화하면서 일반적인 호기성 퇴비화 공정에서 일어나는 질소의 거동을 분석하였다. 음식쓰레기는 종이나 나무조각과 혼합하여 퇴비화하였으며, 질소성 물질의 거동을 평가하기 위해 퇴비시료에 포함된 암모니아, 산화성 질소, 유기성 질소를 측정하였다. 배가스로 손실되는 질소도 황산으로 흡수시켜 정량하였다. 퇴비화 반응의 활성화 여부가 유기성 질소의 무기화에 큰 영향을 미치는 것으로 조사되었다. 활성이 좋은 퇴비를 식종한 경우 반응 초기부터 유기성 질소의 무기화가 활발히 진행되어 많은 양의 질소가 손실된 반면 초기의 낮은 pH 기간이 길어지면 유기성 질소의 분해가 지연되는 것으로 나타났다. 암모니아 손실량은 주입된 공기량의 영향이 큰 것으로 판단되며, 암모니아 손실이 증가하면 퇴비의 암모니아 함량이 크게 감소하였다. 질소에 대한 물질수지 분석을 통하여 초기 질소의 28~38%가 암모니아로 전환되었으며, 전환된 암모니아의 77~94%가 가스로 손실된 것으로 나타났다.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.133-142
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• 2007

화학비료의 과다사용으로 환경오염의 문제가 심각해 지면서 친환경 농자재(목초재 또는 축산분뇨 등)를 사용하는 유기농업의 필요성이 대두되어 왔다. 이러한 친환경 농자재의 시용량은 작물 종류별, 토양 종류별, 계절별, 재배환경 등에 따라 결정되어져야 한다. 유기비료로서 축산분뇨량의 효율적 사용과 축산분뇨로부터의 암모니아 방출량 저감을 위해서는 먼저 축산분뇨의 경작지 시비 후 암모니아 방출모델이 제시되어야 한다. 그리고 암모니아 방출에 영향이 큰 인자들을 찾아내어 이 인자들을 변화시킴으로서 암모니아 방출량을 감소시킬 수 있을 것이다. 이 연구에서는 인공신경망(artificial neural network) 기법을 이용하여 시비된 돈분의 암모니아 휘산량을 예측한다. 유럽지역에서 얻은 암모니아 방출 실험데이터(ALFAM database)를 바탕으로, 암모니아 손실 영향인자에 따른 암모니아 방출량을 Michaelis-Menten 모델식을 이용하여 예측한다. 이 모델식의 모델인자(암모니아 최대 방출량과 암모니아 최대 방출량의 50%에 도달하는 시간)는 feedforward-backpropagation 인공신경망 기법으로 예측하였고, 가중치 분할법(weight partitioning method)으로 암모니아 손실에 미치는 총 15개의 영향인자의 상대적인 중요도를 분석하였다. 그 결과 암모니아 방출량은 기후에 따라 크게 좌우되고, 돈분의 상태도 상당한 영향을 주고 있다.

• 한국작물학회지
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• 제44권3호
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• pp.230-235
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• 1999

To study the effects of an urease inhibitor, N-(n-butyl)-thiophosphoric triamide (NBPT), and a nitrification inhibitor, dicyandiamide (DCD), on nitrogen losses and nitrogen use efficiency, urea fertilizer with or without inhibitors and slowrelease fertilizer (synthetic thermoplastic resins coated urea) were applied to direct-seeded flooded rice fields in 1998. In the urea and the urea+DCD treatments, NH$_4$$^{+}$ -N concentrations reached 50 mg N L$^{-1}$ after application. Urea+NBPT and urea+ NBPT+DCD treatments maintained NH$_4$$^{+}$ -N concentrations below 10 mg N L$^{-1}$ in the floodwater, while the slow-release fertilizer application maintained the lowest concentration of NH$_4$$^{+}$ -N in floodwater. The ammonia losses of urea+NBPT and urea+NBPT+DCD treatments were lower than those of urea and urea+DCD treatments during the 30 days after fertilizer application. It was found that N loss due to ammonia volatilization was minimized in the treatments of NBPT with urea and the slow-release fertilizer. The volatile loss of urea+DCD treatment was not significantly different from that of urea surface application. It was found that NBPT delayed urea hydrolysis and then decreased losses due to ammonia volatilization. DCD, a nitrification inhibitor, had no significant effect on ammonia loss under flooded conditions. The slow-release fertilizer application reduced ammonia volatilization loss most effectively. As N0$_3$$^{[-10]}$ -N concentrations in the soil water indicated that leaching losses of N were negligible, DCD was not effective in inhibiting nitrification in the flooded soil. The amount of N in plants was especially low in the slow-release fertilizer treatment during the early growth stage for 15 days after fertilization. The amount of N in the rice plants, however, was higher in the slow-release fertilizer treatment than in other treatments at harvest. Grain yields in the treatments of slow-release fertilizer, urea+NBPT+ DCD and urea+NBPT were significantly higher than those in the treatments of urea and urea+DCD. NBPT treatment with urea and the slow-release fertilizer application were effective in both reducing nitrogen losses and increasing grain yield by improving N use efficiency in direct-seeded flooded rice field.field.

• 한국환경농학회지
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• 제28권4호
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• pp.392-396
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• 2009

For the reduction of ammonia ($NH_3$) volatilization from the cow manure composting process, a cow manure pile was covered with vinyl (white polyethylene) and the ammonia emissions were evaluated using the dynamic chamber system for 47 days. Nitrogen and phosphorus loss from cow manure pile by rainfall was also measured in this study. In the cow manure pile without covering, the amount of $NH_3$ emission was 0.78 N kg/Mg which accounted for 9.4% of total nitrogen contents in the cow manure. Eighty nine percent of the total $NH_3$ emission during experimental period from the cow manure pile without covering was emitted for the first 21 days. The vinyl covering of cow manure pile reduced 91% of $NH_3$ emission compared to the pile without covering. The amounts of nitrogen and phosphorus loss by rainfall from cow manure pile without covering were 1.27 N kg/Mg and 0.23 P kg/Mg for 47 days, respectively. Results from this study demonstrated that vinyl covering of cow manure pile could reduce $NH_3$ emission and loss of nitrogen and phosphorus by rainfall during composting.

• 한국농공학회지
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• 제43권6호
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• pp.143-153
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• 2001

Hog manure amended with sawdust (moisture 56~60% wet basis, C/N 19-21) was composted in pilot-scale vessels using continuous aeration(CA) and intermittent aeration(IA) for 3 and 4 weeks. In two subsequent runs of the same duration, composts resulting from each of the first runs were used as a biofilter on the exhaust gas from newly composting material. Conditions between each of these paired sets appeared to be similar. Ammonia was released from the biofilter material during the first week of stabilization while the compost produced ammonia after the first week of composting. In both cases substantial absorption, 61~96 %, of ammonia production from the composting raw material was achieved in the stabilizing material during the final weeks of operation and indicates the use of the stabilizing hog manure/sawdust compost as a biofilter can reduce ammonia emissions. Total $NH_3-N$ emissions during run 2 in IA was less than 2/3 of those in CA. Dry solids loss for the stabilized compost (6~8 weeks) was 19~46%.

• Journal of Plant Biology
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• 제14권3호
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• pp.43-46
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• 1971

Losses of nitrogenin the gaseous form were determined with closed systems in the filed under different vegetation types. Ammonia volatilization was greatest from the pine stand, and least from the sod stand, and was greatly reduced in all three sites in the rainy season due to the low temperature. There were only insignificant differences in the nitrogen dioxide volatilization from the soil of the three vegetation types. Losses of ammonia and nitrogen dioxide at various soil depth also showed little variation. Evidently the microbial activity responsible for the $NO_2$ loss was relatively unaffected by the changes in temperature and soil moisture content during the investigation.

• Korean Chemical Engineering Research
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• 제48권2호
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• pp.253-258
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• 2010

암모니아수를 이용한 이산화탄소 흡수분리공정에서 흡수액의 재생조건(온도, 압력)이 이산화탄소 흡수성능에 미치는 영향을 조사하였다. 실험에 사용된 흡수액은 탄산암모늄($(NH_4)_2CO_3$)을 물에 용해시키어 $CO_2$ 로딩($mol\;CO_2/mol\;NH_3$)이 0.5, 용액 내의 암모니아수 농도가 14, 20, 26 및 32 wt%로 되도록 제조하였고, 이산화탄소의 흡수에 앞서 재생압력(6~18 bar)을 조절하면서 $120{\sim}160^{\circ}C$의 온도범위로 제조된 흡수액을 가열하여 재생하였다. 재생된 흡수액을 기포 반응기에 넣고 12 vol%의 $CO_2$를 함유한 기체를 주입하여 흡수반응을 수행하였다. 실험결과 26 wt%의 암모니아수가 대체적으로 $CO_2$ 흡수량이 높았으며, 특히 재생온도가 $150^{\circ}C$, 재생압력이 14 bar일 때의 $CO_2$ 흡수량은 본 연구의 실험조건에서 $45ml\;CO_2/g$ solution으로 가장 높은 값을 보였다. 적정을 통해 재생된 용액을 분석한 결과 재생압력이 높아질수록 암모니아 손실량은 감소하고, 재생온도가 높아질수록 암모니아 손실량이 증가하였다. 또한 암모니아 농도증가에 따라 암모니아 손실량이 비례적으로 증가하였다. Electrolyte NRTL 모델을 사용하여 Aspen Plus에 적용한 결과 실험 데이터와 거의 일치함을 보였다.