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[ $CO_2$ ] Recovery from LNG-fired Flue Gas Using a Multi-staged Pilot-scale Membrane Plant (파일럿규모의 다단계 막분리 공정을 통한 LNG 연소 배가스로부터 이산화탄소의 회수연구)

  • Kim, Jeong-Hoon;Choi, Seung-Hak;Kim, Beom-Sik;Lee, Soo-Bok;Lee, Yong-Taek
    • Membrane Journal
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    • v.17 no.3
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    • pp.197-209
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    • 2007
  • In this study, a multi-staged pilot-scale membrane plant was constructed and operated for the separation of $CO_2$ from LNG-fired boiler flue gas of 1,000 $Nm^3/day$. The target purity and recovery ratio of $CO_2$ required for the pilot plant were 99% and 90%, respectively. For this purpose, we previously developed the asymmetric polyethersulfone hollow fibers and evaluated the effects of operating pressure and feed concentration of $CO_2$ on separation performance[1,2]. The permeation data obtained were also analyzed in relation with the numerical simulation data using counter-current flow model[3,4]. Based on these results, we designed and prepared the demonstration plant consisting of dehumidification process and four-staged membrane process. The operation results using this plant were compared with the numerical simulation results on multi-staged membrane process. The experimental results matched well with the numerical simulation data. The concentration and the recovery ratio of $CO_2$ in the final stage permeate stream were ranged from $95{\sim}99%$ and $70{\sim}95%$, respectively, depending on the operating conditions. This study demonstrated the applicability of the membrane-based pilot plant for $CO_2$ recovery from flue gas.

Effects of Dietary Supplementation of Red Ginseng Mare and Korean Mistletoe Powder on Performance and Meat Quality of Broiler Chicken (사료 내 홍삼박과 겨우살이 분말 첨가 급여가 육계의 생산성 및 계육의 품질에 미치는 영향)

  • Kim, Young-Jik
    • Korean Journal of Poultry Science
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    • v.41 no.3
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    • pp.197-204
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    • 2014
  • The objective of this study was to evaluate the effects of different levels of red ginseng mare or Korean mistletoe powder on growth performance and physicochemical properties of thigh meat in broiler. A total of 200 broiler chicks were divided into five groups were fed a basal diet (control), basal diet supplemented with 0.5% red ginseng mare (T1), red ginseng mare 1% added (T2), Korean mistletoe 0.5% added (T3), Korean mistletoe 0.5% added (T4) for five weeks. Growth performance and proximate composition of chicken thigh meat were not influenced by all treatments, except for mortality and crude fat, which was significantly lower in all treatments with red ginseng mare or Korean mistletoe powder compared to control. Dietary red ginseng mare and Korean mistletoe supplementation had no significantly effects on pH, WHC, shear force, CIE $L^*$, $b^*$ values, triglyceride and glucose but TBARS values total cholesterol, and LDL-cholesterol were decreased (P<0.05) by the addition red ginseng mare and Korean mistletoe powder. CIE $a^*$ values increased significantly with added red ginseng mare and Korean mistletoe powder relative to the control (P<0.05). It was concluded that the addition of red ginseng mare and Korean mistletoe powder revealed minor improvements in the lipid oxidative stability of chicken meat.

Pre-treatment Characteristics of Night Soil by Microbubble (마이크로버블을 이용한 분뇨의 전처리 특성)

  • Lim, Ji-young;Kim, Hyun-sik;Park, Soo-young;Kim, Jin-Han
    • Journal of the Korea Organic Resources Recycling Association
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    • v.24 no.4
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    • pp.31-37
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    • 2016
  • This study was conducted to investigate the effect of OH radicals on organic matter oxidation and suspended solids removal using microbubble as a pre-treatment technique to reduce the organic load of night soil in connection with sewage. The experiment was conducted for three months at HRT 4 hours using pressurized type microbubble generator. The mean SS removal efficiency was achieved 71%. The average removal efficiency of $TCOD_{Cr}$, TBOD, TN and TP were achieved for 51.5%, 47.9%, and 14.7% respectively, as scum and SS were removed by flotation separation. The removal efficiency of soluble organic matters were 25.0%, 17.1% for $SCOD_{Cr}$, SBOD by air microbubble supply. Soluble nitrogen and phosphorus were removed average of 11.9% and 7.4%, respectively. As s result, it was confirmed that soluble organic matters were removed by air microbubble supplied. Generated OH radicals when the microbubble was collapsed, can decompose the soluble organic matters. Therefore, The microbubble flotation process was installed at the front of night soil treatment process, it will contribute to the stable operation of the subsequent biological treatment facility by oxidation of the dissolved organic matters as well as removal of SS by flotation separation.

Tunnelling in Bangkok - Two Case Studies (방콕의 터널공사 - 두 개의 사례연구)

  • Teparaksa, Wanchai;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.7 no.2
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    • pp.153-163
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    • 2005
  • This paper presents two case studies for tunnelling in Bangkok: a subway tunnel site and a flood diversion tunnel site. The first case study is related to ground displacement response for dual tunnel Bangkok MRT subway. The MRT subway project of Bangkok city consists of dual tunnels about 20 km long with 18 subway stations. The tunnels are seated in the firm first stiff silty clay layer between 15-22 m in depth below ground surface. The behavior of ground deformation response based on instrumentation is presented. The back analysis based on plain strain FEM analysis is also presented and agrees with field performance. The shear strain of FEM analysis is in the range of 0.1-1% and in accordance with the results of self boring pressuremeter tests. Meanwhile, the second case study is related to the EPB tunnelling bored underneath through underground obstruction. The Premprachakorn flood diversion tunnel is the shortcut tunnel to divert the flood water in rainy season into the Choapraya river. The tunnel was bored by means of EPB shield tunnelling in very stiff silty clay layer at about 20-24 m in depth. During flood diversion tunnel bored underneath the existing Bangkok main water supply tunnel and pile foundation of the bridge, instrumentation was monitored and compared with predicted FEM analysis. The prevention risk potential by means of predicting damage assessment is also presented and discussed.

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Predicting ground condition ahead of tunnel face utilizing electrical resistivity applicable to shield TBM (Shield TBM에 적용 가능한 전기비저항 기반 터널 굴착면 전방 예측기술)

  • Park, Jin-Ho;Lee, Kang-Hyun;Shin, Young-Jin;Kim, Jae-Young;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.6
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    • pp.599-614
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    • 2014
  • When tunnelling with TBM (Tunnel Boring Machine), accessibility to tunnel face is very limited because tunnel face is mostly occupied by a bunch of machines. Existing techniques that can predict ground condition ahead of TBM tunnel are extremely limited. In this study, the TBM Resistivity Prediction (TRP) system has been developed for predicting anomalous zone ahead of tunnel face utilizing electrical resistivity. The applicability and prediction accuracy of the developed system has been verified by performing field tests at subway tunnel construction site in which an EPB (Earth Pressure Balanced) shield TBM was used for tunnelling work. The TRP system is able to predicts the location, thickness and electrical properties of anomalous zone by performing inverse analysis using measured resistivity of the ground. To make field tests possible, an apparatus was devised to attach electrode to tunnel face through the chamber. The electrode can be advanced from the chamber to the tunnel face to fully touch the ground in front of the tunnel face. In the 1st field test, none of the anomalous zone was predicted, because the rock around the tunnel face has the same resistivity and permittivity with the rock ahead of tunnel face. In the 2nd field test, 5 m thick anomalous zone was predicted with lower permittivity than that of the rock around the tunnel face. The test results match well with the ground condition predicted, respectively, from geophysical exploration, or directly obtained either from drilling boreholes or from daily observed muck condition.

Removal of Ammonia-Nitrogen Contained in Landfill Leachate by Ammonia Stripping(I) (암모니아 탈기공정을 이용한 침출수의 암모니아성 질소제거(I))

  • Lee, Byung-Jin;Cho, Soon-Haing
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1893-1904
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    • 2000
  • Nitrogen compounds are one of the major pollutants which cause eutrophication problems of the river or lake and red tides problems of the ocean. Currently available technologies for the removal of nitrogen compounds are mostly biological treatment. However, biological treatment is only effective for the wastewater which contains low concentration of nitrogen compounds. Leachate from solid waste landfill or industrial wastewater which contains high concentration of nitrogen can not be effectively treated by most of the currently available biological treatment technologies. With this connection. the objective of this study is to examine the applicability of ammonia stripping technology for the removal of high concentration of ammonia nitrogen compounds of the leachate from solid waste landfill. It can be concluded that ammonia stripping technology which was placed before the biological treatment process was very effective for the removal of high concentration of ammonium compounds. The chemical cost for the ammonia stripping was 16 percent higher than MLE process, so other methods like sludge recycling are needed for the reduction of operation cost. Further details are discussed in this paper.

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Effects of Immersion Period after Tumbling Processing on the Quality Properties of Boiled Pork Loin with Soy Sauce (텀블링 공정 후 침지기간이 간장첨가 삶은 돈육의 품질 특성에 미치는 영향)

  • Choi, Yun-Sang;Jeong, Jong-Youn;Choi, Ji-Hun;Lee, Mi-Ae;Lee, Eui-Soo;Kim, Hack-Youn;Han, Doo-Jeong;Kim, Jin-Man;Kim, Cheon-Jei
    • Korean journal of food and cookery science
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    • v.22 no.3 s.93
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    • pp.379-385
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    • 2006
  • The purpose of this study was to investigate the effects of immersion period after tumbling on the physicochemical properties of boiled pork loin with soy sauce. After the samples were tumbled for 30 min with soy sauce (1.5% salt concentration), they were immersed for 1, 5 or 10 days. Boiled pork loin was cooked at an internal temperature to $75^{\circ}C$. Cooking yields of boiled pork loin were significantly increased with increasing immersion period. The reduction in diameter and thickness for pork loin were significantly decreased with increasing immersion period, but moisture content and water holding capacity were increased. Shear force in the immersed samples after tumbling was significantly lower than in the control. In sensory evaluation color, flavor, texture, and juiciness of boiled pork loin immersed after tumbling should higher ratings than those of control.

Quality Characteristics of Replacing Pork Hind Leg with Pork Head Meat for Hamburger Patties (돈육 후지를 머리고기로 대체한 햄버거 패티의 품질 특성)

  • Choi, Yun-Sang;Jeon, Ki-Hong;Ku, Su-Kyung;Sung, Jung-Min;Choi, Hyun-Wook;Seo, Dong-Ho;Kim, Cheon-Jei;Kim, Young-Boong
    • Korean journal of food and cookery science
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    • v.32 no.1
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    • pp.58-64
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    • 2016
  • The effects of reducing pork hind legs concentrations from 80% to 60% and replacing the pork head meat with up to 20% pork head meat were investigated based on chemical composition, cooking characteristics, physicochemical properties, shear force, and sensory characteristics of hamburger patties. The increasing the pork head levels from 0% to 20% increased the protein content, pH, reduction in diameter, reduction in thickness, and shear force of hamburger patties, but decreased the moisture content, lightness, redness, yellowness, cooking yield, and water holding capacity of hamburger patties. The fat and ash contents of the hamburger patties with different amounts of pork hind legs and pork head showed no significantly different sensory characteristics from the control and all the treatments (p>0.05). The hamburger patties with increasing pork head levels had lower color, flavor, juiciness, and overall acceptability scores, but the overall acceptability of control showed similar trends to T1 and T2. Therefore, replacing pork hind legs with pork head meat in the formulation was successfully similar to control hamburger patties, with best results obtainedon replacing up to 10% pork head meat.

A Study on the Appropriateness of Duck Meat Processing According to Feeding Management (사양관리에 따른 오리 육의 가공 적정성에 관한 연구)

  • Li, Guan-Hao;Choe, Il-Sin;Nam, Ki-Taeg;Kim, Sang-Hyun;O, Baatartsogt.;Lee, Chi-Ho;Choi, Kang-Duk
    • Food Science of Animal Resources
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    • v.27 no.2
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    • pp.203-208
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    • 2007
  • Organic duck's carcass weight was lower than general duck's because of the differences in breed and feeding method, but there was no difference in carcass percent among them. The rate of organic duck's fresh breast meat(17.62%) was significantly higher than that of general duck's(11.95%)(p<0.05). The rate of fresh leg meat rate was lower in organic duck, but there was no significant difference among them(p>0.05). The pH of breast and leg measured immediately after butchering were 6.48 and 6.73 in organic duck, respectively and there was significant difference among them(p<0.05). According to the sensory test, the texture, odor, tenderness, and taste showed better preference in organic duck than those of broiler chicken. According to above physicochemical analysis and sensory test, organic duck showed higher pH, higher shear force, and lower cooking loss. Therefore, it is considered to be very valuable to develop the exploitation of meat product in organic duck which had good quality and tastiness.

Static Behavior of Gravelly Soil with State Parameter (상태정수에 따른 자갈질 흙의 정적거동)

  • Heo, Seungbeom;Yoon, Yeowon;Kim, Woosoon;Kim, Jaeyoun
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.8
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    • pp.5-14
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    • 2010
  • Recent researches on the behavior of gravelly soils have been focused mainly on the relative density or on the gravel content. And some researchers presented the liquefaction behavior based on the relative density whereas others based on the gravel content of gravelly soil. However the relative densities vary with gravel content and relative density is not enough to fully express the behavior of gravelly soils. Therefore in this research state parameter which considers void ratio and effective confining pressure is introduced and Steady State Line(SSL) of gravelly soils for various gravel content are determined by undrained triaxial tests in order to express the behavior of gravelly soils. From the research the position of SSL moved downward with gravel content. And the same density of soil showed dense sand behavior or loose sand behavior depending upon the confining pressure. Especially relative density 80% of gravelly soil showed loose sand behavior under high confining pressure. However the gravelly soils with similar state parameters showed similar stress behaviors. It can bee seen that state parameter is useful tool to evaluate undrained behavior of gravelly soils. Also state parameter and undrained strength showed good correlations.