• 한국산업보건학회지
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• 제16권1호
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• pp.36-43
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• 2006

The principal aim of this field study was to determine the concentrations and emissions of gaseous contaminants such as ammonia and hydrogen sulfide in the different types of pig buildings in Korea and allow objective comparison between Korea and the other countries in terms of pig housing types. This field study was performed from May to June and from September to October in 2002. Pig buildings investigated in this research were selected in terms of three criteria; manure removal system, ventilation mode and growth stage of pig. Measurements of concentration and emission of ammonia and hydrogen sulfide in the pig buildings were done in 5 housing types and the visited farms were 15 sites per each housing type. Concentrations of ammonia and hydrogen sulfide were measured at three locations of the central alley in the pig building and emission rates of them were estimated by multiplying the average concentration($mg/m^3$) measured near the air outlet by the mean ventilation rate($m^3/h$) and expressed either per pig of liveweight 75kg(mg/h/pig) or per area($mg/h/m^2$). Concentrations of ammonia and hydrogen sulfide in the pig buildings were averaged to 7.5 ppm and 286.5 ppb and ranged from 0.8 to 21.4 ppm and from 45.8 to 1,235 ppb, respectively. The highest concentrations of ammonia and hydrogen sulfide were found in the mechanically ventilated buildings with slats; 12.1 ppm and 612.8 ppb, while the lowest concentrations of ammonia and hydrogen sulfide were found in the pig buildings with deep-litter bed system(2.2 ppm) and the naturally ventilated pig buildings with manure removal system by scraper(115.2 ppb), respectively(p<0.05). All the pig buildings were investigated not to exceed the threshold limit values(TLVs) of ammonia(25 ppm) and hydrogen sulfide(10 ppm). The mean emissions of ammonia and hydrogen sulfide per pig(75kg in terms of liveweight) and area($m^2$) from pig buildings were 250.2 mg/h/pig and 37.8 mg/h/pig and $336.3mg/h/m^2$ and $50.9mg/h/m^2$, respectively. The pig buildings with deep-litter bed system showed the lowest emissions of ammonia and hydrogen sulfide(p<0.05). However, the emissions of ammonia and hydrogen sulfide from the other pig buildings were not significantly different(p>0.05). Concentrations and emissions of ammonia and hydrogen sulfide were relatively higher in the pig buildings managed with deep-pit manure system with slats and mechanical ventilation mode than the different pig housing types. In order to prevent pig farm workers from adverse health effect caused by exposure to ammonia and hydrogen sulfide in pig buildings, they should wear the respirators during shift and be educated sustainably for the guideline related to occupational safety.

• 한국환경보건학회지
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• 제40권2호
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• pp.127-136
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• 2014

Objectives: This study was conducted to investigate the removal of high odor concentration from swine wastewater treatment facility by full scale biofilter using liquid with deodorant mixed with earthworm cast and distillery sludge. Methods: The supply of the culture liquid to the microorganism on the media in the biofilter increases the activity and growth of biomass. The experimental equipment was biofilter tower with treatment capacity of 90 m 3/min. The experimental conditions included gas flow of $60m^3/min$, retention time of 20 sec, and gas/liquid ratio of 67. Results: With changing season from winter to summer, the inlet odor concentration of ammonia increased from 2.5 ppm to 29 ppm, and of hydrogen sulfide from 21 ppm to 91 ppm, respectively. The odor treatment system with biofilter using the culture liquid was stable when the high loading rate increased and showed excellent removal grade with an average of 96.7% for ammonia, and an average of 93.7% for hydrogen sulfide. The pH and SCOD in the recirculating culture liquid near the bottom of the biofilter tower decreased with operation time, but its influence on the odor removal rate was negligible, because the organic matter (SCOD) was replaced by some culture liquid supplied 2-4 times per day. Conclusions: The biofilter using culture liquid could successfully remove high odor concentration which was generated from swine wastewater treatment facility.

• Journal of Microbiology and Biotechnology
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• 제13권2호
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• pp.301-304
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• 2003

In this study, hydrogen sulfide ($H_2S$), ammonia ($NH_3$), and benzene, which represent the major odor from a natural leather process plant, were removed using a fluidized bed bioreactor and biofilter including Thiobacillus sp. IW and a MY microbial consortium. The critical removal rate was $12g m^{-3}h^{-1}\;for\;H_2S,\;11g m^{-3}h^{-1}\;for\;NH_3\;and\;28 g m^{-3}h^{-1}$ for benzene by the fluidized bed bioreactor, and $8.5g m^{-3}h^{-1}\;for\;H_2S\;7g m^{-3}h^{-1}\;for\;NH_3,\;and\;25 g m^{-3}h^{-1}$ for benzene in the biofilter. The average removal efficiency of $H_2S$, $NH_3$, and benzene by continuous operation for over 30 days with the fluidized bed bioreactor was $95{\pm}3\%,\;99{\pm}1\%,\;and\;98{\pm}5\%$, respectively, whereas that with the biofilter was $96{\pm}4\%,\;95{\pm}4\%,\;and\;97{\pm}3\%$, respectively. Therefore, the critical removal rate of $H_2S$, $NH_3$, and benzene was higher in the fluidized bed bioreactor, whereas the removal efficiency on the continuous operation was similar in both bioreactors.

• 한국축산시설환경학회지
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• 제12권2호
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• pp.95-100
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• 2006

양돈액비에서 인을 회수하기 위한 연속식 공정을 개발하고자 시험을 수행하였다. $MgCl_2$를 마그네슘 원으로 사용하였고 pH를 NaOH로 조정해준 구와 폭기를 시켜준 구를 서로 비교하였다. 몰비가 증가할수록 용해인의 회수율도 증가함을 알 수 있었다. 1. pH를 NaOH로 조정하였을 때 비육돈사 액비의 경우에 용해인은 몰비 1:1.5에서 초기값 353(${\pm}9$)mg/L에서 19(${\pm}1.6$)mg/L로 감소하여 95%의 회수효과를 보았으며, 암모니아성 질소의 경우에는 5,527(${\pm}174$)mg/L에서 5,009(${\pm}161$)mg/L로 감소하여 9%의 제거율을 나타내었다. 2. 자돈사 액비의 경우에 몰비 1:1.5에서 용해인은 초기치 111(${\pm}2.8$)mg/L에서 1(${\pm}1.1$)mg/L로 감소하여 회수율은 98%를 나타내었으며, 암모니아성 질소의 경우에는 2,317 (${\pm}37$)mg/L에서 2,226(${\pm}39$)mg/L으로 감소하여 제거율 4%를 나타내었다. 3. 자돈사 액비의 경우에 폭기공정의 몰비 1:1.5에서 용해인은 초기값 321(${\pm}10.2$)mg/L에서 113(${\pm}3.6$)mg/L로 감소하여 회수율은 66%로 되었으며, 암모니아성 질소의 경우에는 2,364(${\pm}5$)mg/L에서 2,017(${\pm}2$)mg/L로 낮아져서 제거율은 15%로 높게 나타났다. 4. pH를 NaOH로 조정해준 구가 폭기를 시켜준 구보다 용해인 회수에서 효과가 좋았다. 암모니아성 질소의 제거에서는 반대로 폭기구에서 높게 나타났다.

• Korean Chemical Engineering Research
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• 제51권3호
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• pp.335-341
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• 2013

목질계 바이오매스인 옥수수대 전처리를 위하여 고안된 순환식 암모니아 전처리 반응기(Ammonia Circulation Reactor (ACR))를 이용하여 연구하였다. 이 전처리 방법은 적은 양의 액체를 사용하도록 고안되었으며 이 연구에선 기존의 전처리 공정보다 낮은 전처리 온도($60{\sim}80^{\circ}C$), 반응시간(4~12 hour) 그리고 고체:액체 비율(1:3~1:8) 등의 공정 조건을 실험 하여 효과를 비교하였다. 즉 여러 공정 조건에서 전처리 후 고형물의 잔류 고체량, 당, Lignin 함량, 그리고 효소당 화율 등을 측정하였다. 여러 실험 조건에서 공통적으로 관찰된 것은 전처리 조건이 더 가혹해 지면 Lignin의 제거율이 가장 큰 영향을 받았으며, 47.6~70.6% 범위로 나타났다. 반면 다른 당(Glucan, Xylan)은 손실이 비교적 작게 나타났다. 모든 실험 조건에서, 전처리된 고형물의 Glucan 손실율은 4.7~15.2% 범위로 변화가 크지 않았으며 Xylan 손실율은 여러 조건의 변화에 따라 7.4~25.8% 정도 범위로 나타났다. 암모니아 순환 전처리로 8~12 hour 동안 처리된 옥수수대는 90.1~94.5%의 높은 72-h Glucan 당화율을 (15 FPU-GC220+30 CBU)/g-glucan의 효소 투입으로 나타냈으며 순수 Cellulose인 Avicel의 당화율(92.7%)과 비슷하거나 높았다. 또한 8~12 hour 처리된 옥수수대의 초기 24-h Glucan 당화속도는 73.0~79.4%로 Avicel의 같은 시간 당화율인 69.5% 보다 높게 나타났다. 반응시간을 증가는 보다 많은 Lignin을 제거하였으며 따라서 효소 당화율 증가에 기인한 것으로 보인다.

• 한국해양환경ㆍ에너지학회지
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• 제7권3호
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• pp.116-121
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• 2004

고밀도 순환여과식 해산어 양식장의 순환수 처리에 EMMC공정의 적용 가능성을 평가하기 위한 실험을 실시하였다. 처리공정의 운전효율에 유기물 및 암모니아성 질소 부하가 미치는 영향을 평가하기 위하여 수리학적 체류기간을 12시간에서 10분까지 점차적으로 줄여가며 실험을 실시하였다. HRT 2시간까지는 수리학적 체류시간 변화에 따른 제거효율 변화가 거의 없었으나 그 이하의 체류시간에서는 체류시간 단축에 따른 제거효율의 감소가 비교적 크게 나타났다. COD의 경우에는 체류시간 단축에 따른 급격한 제거효율의 변화가 관측되지 않았으며 10분 정도의 체류시간에서도 90％이상의 제거효율을 나타내었다. 메디아 충진율에 따른 반응조 운전효율변화를 보면 HRT가 1시간보다 긴 경우에는 메디아 충진율에 따른 제거효율 변화가 극히 미미하였다. 그러나 1시간 이하의 체류시간에서는 그 차가 상당히 크게 나타나 충진량이 많을수록 제거효율이 높게 나타났으나 50％이상의 메디아 충진이 반응조 운전효율 측면에서는 큰 역할을 하지 못함을 나타내어 경제성 등을 고려할 경우 25％정도만을 충진 시키는 것이 오히려 합리적이라 판단되었다. 이와 같은 경향은 암모니아성 질소 제거의 경우에도 유사한 양상을 나타내었다. 메디아 충진율 50％와 75％사이에는 처리효율의 차이가 거의 없었고 25％충진 반응조와의 차이도 그리 크지 않은 것으로 나타났다.

• 환경위생공학
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• 제13권1호
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• pp.44-56
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• 1998

This study was performed to investigate the reaction characteristics of piggery wastewater for biological nutrient removal. The reaction characteristics were discussed the fraction of organics, the behavior of nitrogen, nitrification, denitrification, and the behavior of phosphorus. The fraction of readily biodegradable soluble COD was 11-12 percent. The ammonia nitrogen was removed via stripping, nitrification, autotrophic cell synthesis, and heterotrophic cell synthesis. The removal percents by each step were 12.1%, 68.9%, 15.0%, and 4.0%, respectively. Nitrification inhibition of piggery wastewater was found to occur at an influent volumetric loading rate over 0.2 NH$_{3}$-N kg/m$^{3}$/d. Denitrification rates were the highest in the raw wastewater and the lowest in the anaerobic effluent. The denitritation of piggery wastewater came out to be possible, and the rate of organic carbon consumption decreased about 10 percent. The phosphorus removed was released in the form of ortho-p in the aerobic fixed biofilm reactor, it was caused by autooxidation. The synthesis and release of phosphorus were related to the ORP and the boundary value for the phase change was about 170mV. In the synthesis phase, the phosphorus removal rate per COD removed was 0.023mgP$_{syn}$/mgCOD$_{rem}$. The phosphorus contents of the microorganism were 4.3-6.0% on a dry weight basis.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.406-409
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• 1999

Experimental Investigations were carried out to remove NOx, SOx simultaneously from simulated flue gas[NO(0.02%)-SO$_2$(0.08%)-$CO_2$-Air-$N_2$] by using a plasma chemical reaction. Ammonia gas(14.81%) balanced by argon was diluted by all and was Introduced to mall simulated flue gas duct through NH$_3$ Injection system which is in downstream of reactor. The NH$_3$ molecular ratio(MR) was determined based on (NH3) to [NO+S0$_2$]. MR is 1, 1.5, 2.5. The NOx removal rate significantly increased with increasing NaOH bubble quantity. The SO$_2$ removal rate was not significantly effected by applied voltage, however it fairly Increased with increasing NH$_3$ molecule ratio. By-product aerosol particle was observed by XRD(X-ray diffraction) after sampling, The NOx, SOx removal rates, when H2O vapour bubbled by dry all was injected to plasma reactor, were better than those of other cases. When aqueous NaOH solution(20%) bubbled by 2.5( ι /min) of $N_2$ and 0.5 ( ι /min) NH$_3$(MR=1.5) were injected to simulated flue gas, The NOx. SOx removal rate was 95 ~ 100[%]

• Environmental Engineering Research
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• 제25권2호
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• pp.135-146
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• 2020

This study was aimed to investigate the possibility of using raw and anaerobically-digested piggery wastewater as culture media for a green microalga Chlorella vulgaris (C. vulgaris). Due to high concentration of ammonia and dark color, the microalga did not grow well in this wastewater. In order to solve this problem, air stripping and NaOCl-treatment were applied to reduce the concentration of NH₃-N and the color intensity from the wastewater. Algal growth was monitored in terms of specific growth rate, biomass productivity, and nutrient removal efficiency. As a result, C. vulgaris grew without any sign of inhibition in air-stripped and 10-folds diluted anaerobically-digested piggery wastewater with enhanced biomass productivity of 0.57 g/L·d and nutrient removal of 98.7-99.8% for NH₃-N and 41.0-62.5% for total phosphorus. However, NaOCl-treatment showed no significant effect on growth of C. vulgaris, although dark color was removed greatly. Interestingly, despite that the soluble organic concentration after air stripping was still high, the biomass productivity was 4.4 times higher than BG-11. Moreover, air stripping was identically effective for raw piggery wastewater as for anaerobic digestate. Therefore, it was concluded that air stripping was a very effective method for culturing microalgae and removing nutrients from raw and anaerobically-digested piggery wastewaters.

• 한국응용과학기술학회지
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• 제23권2호
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• pp.130-136
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• 2006

Theoretical total nitrogen removal efficiency and reactor volume ratio in oxic-anoxic-oxic system can be found by influent water quality in this study. The influent water quality items for calculation were ammonia, nitrite, nitrate, alkalinity, and COD which can affect nitrification and denitrification reaction. Total nitrogen removal efficiency depends on influent allocation ratio. The total nitrogen removal follows the equation of 1/(1+b). Optimal reactor volume ratio for maximum TN removal efficiency was expressed by those influent water quality and nitrification/denitrification rate constants. It was possible to expect optimal reactor volume ratio by the calculation with the standard deviation of ${\pm}14.2$.