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A Study on the Biological Nitrogen Removal of the Chemical Fertilizer Wastewater Using Jet Loop Reactor (Jet Loop 반응기를 이용한 화학비료폐수의 생물학적 질소제거 연구)

  • Seo Jong-Hwan;Lee Chul-Seung
    • Journal of Environmental Science International
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    • v.14 no.2
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    • pp.157-165
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    • 2005
  • This study was conducted to determine optimum design parameters in nitrification and denitrfication of chemical fertilizer wastewater using pilot plant, Jet Loop Reactor. The chemical fertilizer wastewater which contains low amounts of organic carbon and has a high nitrogen concentration requires a post-denitrfication system. Organic nitrogen is hydrolyzed above $86\%$, and the concentration of organic nitrogen was influent wastewater 126mg/L and of effluent wastewater 16.4mg/L, respectively. The nitrification above $90\%$ was acquired to TKN volumetric loading below $0.5\;kgTKN/m^3{\cdot}d$, TKN sludge loading below $0.1\;kgTKN/kgVSS{\cdot}d$ and SRT over 8days. The nitrification efficiency was $90\%$ or more and the maximum specific nitrification rate was $184.8\;mgTKN/L{\cdot}hr$. The denitrification rate was above $95\%$ and the concentration of $NO_3-N$ was below 20mg/L. This case was required to $3\;kgCH_3OH/kgNO_3-N$, and the effluent concentration of $NO_3^--N$ was below 20mg/L at $NO_3^--N$ volumetric loading below $0.7\;kgNO_3^--N/m^3{\cdot}d$ and v sludge loading below $0.12\;kgNO_3^-N/kgVSS{\cdot}d$. At this case, the maximum sludge production was $0.83\;kgTS/kgT-N_{re}$ and the specific denitrfication rate was $5.5\;mgNO_3-N/gVSS{\cdot}h$.

A Study on the Chemical Components of Acid Deposition (산성 강하물질의 화학적 성분에 관한 연구)

  • 권오영;윤오섭
    • Journal of Environmental Health Sciences
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    • v.20 no.2
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    • pp.39-54
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    • 1994
  • Dry and wet deposition samples were continuously collected by deposit gauge. In Bulkwang area of Seoul and Kanghwa in west coastal area of Korea. In order to evaluate the level of air pollution and its chemical composition, Bulkwang area located in Seoul and Kanghwa in west coastal area were chosen for sampling site. dry deposition concentrations, pH, electric conductivity and water soluble ion concentrations of deposit gauge were analysed. The results of comparison between urban area and coastal area were summarized as follows. Mean concentrations of dry deposition in Bulkwang was 2.807 ton/km$^2$/month (range: 5.171~1.128 ton/km$^2$/month) while that in Kanghwa was 1.990 ton/km$^2$/month (range: 3.358 ~ 1.084 ton/km$^2$/month), which showed a significant difference between two areas. The rainfall during the period from June to September in 1990 recorded 1859.7 mm which was 78.8% of its mean amount in Seoul, and 1846.9 mm which was 81.6% that of Kanghwa. In Bulkwang area, correlation coefficients of deposit chemical composition were 0.95 for SO$_4^{-2}$ and Na$^+$, 0.94 for SO$_4^{-2}$ and NH$_4^+$, 0.93 for CI$^-$ and NH$_4^+$ and 0.85 for Cl$^-$ and Ca$^{2+}$, respectively. Then, the results indicate that sulfates such as $Na_2SO_4$, $(NH_4)_2SO_4$, and CaSO$_4$ were the major chemical state of deposit. In Kanghwa area, it was considered that NaCl, $NH_4NO_3$, NaNO$_3$, and $Ca(NO_3)_2$ were the major chemical state of deposit.

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Antigenicity Study of CFA-001, cefazolin, a cephalosperin Derivative Produced by an :Enzymatic Semisynthesis

  • Park, Jong-Il;Jeong, Tae-Cheon;Kim, Hyoung-Chin;Han, Sang-Seop;Roh, Jung-Koo;Kim, Jeong-Hwan;Jeon, Yeong-Joong;Kim, Dal-Hyun;Kim, Je-Hak;Park, Kwan-Ha
    • Biomolecules & Therapeutics
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    • v.5 no.1
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    • pp.48-52
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    • 1997
  • The antigenic potential of CFA-001, cefazolin, a cephalosporin derivative produced by an enzy-matic semisynthesis, was determined in Hartley guinea pigs. A battery of tests employed consisted of active systemic anaphylaxis (ASA), passive cutaneous anaphylaxis (PCA), and indirect hemagglutination test (IHA). The results were as follows: 1) In ASA, no signs attributable to anaphylaxis was observed in guinea pigs sensitized with CFA-001, whereas OVA-sensitized animals induced severe anaphylactic symptoms; 2) guinea pigs did not produce antibodies against CFA-001 when sensitized with or without Freund's complete adjuvant (FCA) in homologous PCA tests. Meanwhile, antibodies against ovalbumin (OVA) were clearly detected; 3) No CFA-001-specific hemagglutination was observed in the IHA using sera obtained from CFA-001- sensitized guinea pigs. These results suggest that CFA-001 has no antigenicity potential in guinea pigs.

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Analysis of Gas Emissions and Power Generation for Co-firing Ratios of NG, NH3, and H2 Based on NGCC (NGCC 기반 천연가스, 암모니아, 수소 혼소 발전 비율에 따른 CO2와 NOx 배출량 및 전력 생산량 분석)

  • Inhye Kim;Jeongjae Oh;Taesung Kim;Minsuk Im;Sunghyun Cho
    • Korean Chemical Engineering Research
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    • v.62 no.3
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    • pp.225-232
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    • 2024
  • The reduction of CO2 emissions in the energy production sector, which accounts for 86.8% of total greenhouse gas emissions, is important to achieve carbon-neutrality. At present, 60% of total power generation in South Korea is coal and natural gas. Replacing fossil fuel with renewable energy such as wind and solar has disadvantages of unstable energy supply and high costs. Therefore, this study was conducted through the co-firing of natural gas, ammonia and hydrogen utilizing the natural gas combined cycle process. The results demonstrated reduction in CO2 emissions and 34%~238% of the power production compared to using only natural gas. Case studies on mass fractions of natural gas, ammonia and hydrogen indicated that power production and NOx emissions were inversely proportional to the ammonia ratio and directly proportional to the hydrogen ratio. This study provides guidelines for the use of various fuel mixtures and economic analysis in co-firing power generation.