고온건식탈황 유동층 반응기에서 아연계 탈황제의 재생반응에 미치는 산소농도의 영향

조성호,이봉희,진경태,이창근 한국화학공학회 2001 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.39 No.6

Zinc titanate 탈황제를 사용하여 내경 4.5㎝인 소형유동층 반응기에서 재생반응특성을 연구하였다. 산소농도를 5%에서 21%까지 변화시키면서 재생실험을 수행하였다. 산소의 농도변화에 따라 배출되는 SO_2의 최대농도는 양론적으로 이론치와 일치하였다. 발열반응으로 인한 재생반응기의 온도상승은 산소농도가 증가함에 따라 증가하였다. 2차 황화반응 초기에 SO_2가 발생되지 않는 것으로 보아 sulfate가 형성되지 않았다는 것을 확인할 수 있었다. 재생반응 후 시료의 물리-화학적 특성 분석결과 zinc titanate 탈황제는 부반응 및 물성변화가 없는 것으로 판단할 수 있었다. 이와 같은 실험으로 분무 건조법으로 성형된 zinc titanate 탈황제는 유동층 반응기에서 산소농도 21%의 공기로 재생 가능성을 보여 주었다. The regeneration characteristics of spray-dried zinc titanate sorbent in a fluidized bed reactor were examined at temperatures of 650℃ and 700℃ with the regenerated gas of the oxygen concentrations from 5% to 21%. The outlet SO_2 peak concentrations were coincided with the theoretical values depending on inlet O_2 concentration. As the oxygen concentration was increased, the temperature rise in the regeneration reactor was increased due to the heat of exothermic reaction. During the initial stage of the second sulfidation reaction, SO_2 was not detected in the outlet gases. It was an indirect indication that zinc sulfate had not been formed during the first regeneration reaction. The various analysis results showed little differences in physical and chemical properties between fresh and regenerated sorbent.

매체순환식 가스연소기 적용을 위한 Ni계 및 NiO계 산소공여입자의 반응특성

류호정,배달희,조성호,진경태 한국화학공학회 2004 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.42 No.1

매체순환식 가스연소기에 적용하기 위한 최적의 산소공여입자를 결정하기 위해 금속산화물(NiO)의 함량 변화에 따라 네 가지 (NiO 26, 44, 58, 78wt%)의 산소공여입자를 제조하여 열중량 분석기에서 환원반응특성을 측정 및 비교하였다. 제조된 입자들 중에서 NiO 약 60wt%인 입자가 산소전달능력 및 반응속도 면에서 다른 입자들에 비해 우수한 성능을 나타내었다. 산소공여입자의 제조과정에서 금속산화물 형태의 영향을 살펴보기 위해 금속산화물의 출발물질로 Ni과 NiO를 사용하여 NiO 함량이 동일한(약 60%) 두 종류의 입자를 제조하였으며 열중량 분석기와 고정층 반응기를 이용하여 반응속도, 재생성, 환원반응 유지시간 및 CO_(2) 선택도 등을 측정 및 고찰하였다. 금속산화물의 출발물질로 NiO를 사용한 입자가 Ni을 사용한 입자에 비해 반복 실험시에 정상반응조건에 빨리 도달하였고 반응속도와 CO_(2) 선택도가 높았으며 환원반응 유지시간인 길게 나타났다. 실험결과에 의해 본 연구에서 고려한 산소공여입자 중에서 금속산화물의 출발물질로 NiO를 사용한 NiO 함량이 60wt%인 입자를 최적의 산소공여입자로 선정하였다. To find a suitable oxygen carrier particle for chemical-looping combustor, four kinds of particles (NiO 26, 44, 58, 78wt%) were prepared and the reactivity of the reduction was measured and investigated by a thermo-gravimetrical analyzer. From the viewpoint of oxygen transfer capacity and reaction rate, the particle containing 60wt% of NiO showed better performance than the other particles. Also, we have prepared two kinds of oxygen carrier particles to investigate the effect of the starting material for a metal oxide component(i.e., Ni based and NiO based particles, where the weight percents of both samples were set at 60wt% as NiO). The reaction rate, regenerative ability, duration of the reduction, and CO₂ selectivity were easured and investigated by a thermo-gravimetrical analyzer and a fixed bed reactor. The results obtained here indicated that the NiO based oxygen carrier particle containing 60wt% of NiO showed better regenerative ability, reaction rate, CO₂ selectivity, and duration of the reduction, compared with the other particles, therefore we selected this particle as an optimum oxygen carrier particle.

매체순환식 가스연소기 산소공여입자의 최소유동화속도 및 고속유동층으로의 전이유속

류호정,임남윤,배달희,진경태 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.5

기포유동층과 고속유동층의 2탑 연결 가압순환유동층으로 조업되는 매체순환식 가스연소기의 설계와 조업조건 선정을 위해 산소공여입자의 최소유동화속도와 고속유동층으로의 전이유속을 측정 및 고찰하였다. 층물질로 매체순환식 가스연소기의 산소공여입자인 NiO/bentonite (평균입경 : 0.181 mm, 입자밀도 : 4,080 kg/㎥)를 사용하여 가압 기포유동층(내경 0.052 m, 높이 1.66 m)에서 층압력강하를 측정하여 온도(25-1,000℃)와 압력(1-6 atm)의 변화에 따른 최소유동화속도의 변화를 측정 및 고찰하였고 고온순환유동층(내경 0.02 m, 높이 2.0 m)에서 emptying time method에 의해 고속유동층으로의 전이유속(U_(tr))에 대한 온도(25-600℃)의 영향을 측정 및 고찰하였다. 측정된 최소유동화속도는 온도와 압력이 증가함에 따라 감소하였으며, 고속유동층으로의 전이유속은 온도가 증가함에 따라 증가하였다. 최소유동화속도와 고속유동층으로의 전이유속에 대한 본 실험의 측정값을 기존의 상관식과 비교하였으며 기존 상관식을 바탕으로 수정된 상관식을 제시하였다. In order 10 design and select appropriate operating conditions for the practical operation of chemical-loaping combustor, which consists of two interconnected fluidized beds (bubbling fluidized bed and fast fluidized bed), minimum fluidization velocity and transition velocity to fast fluidization were measured and investigated. Oxygen carrier particle of NiO bentonite particle (specific surface mean diameter: 0.181 mm, particle density: 4,080 ㎏/㎥) was used as a bed material. The minimum fluidization velocity was determined by measuring the bed pressure drop in the pressurized fluidized bed (0.052 m i.d. and 1.66 m high) with variations of temperature (25-1,000℃) and pressure (1-6 atm). The transition velocity from bubbling to fast fluidization was determined by means of emptying tim method in the high temperature circulating fluidized bed (0.02 m i.d. and 2.0 m high) with variation of temperature (25-600℃). The measured minimum fluidization velocity was increased with increasing temperature and pressure. The measured transition velocity to fast fluidization was increased with increasing temperature. The previous correlations on the minimum fluidization velocity and transition velocity to fast fluidization were compared with the present measured values to develop new correlation.

가압유동층연소로에서 국내무연탄의 황산화물 배출특성

한근희,송용식,류정인,손재익,진경태 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.1

본 연구는 가압유동충연소로에서 국내 무연탄을 연소함에 있어서 SO_2 배출농도에 대하여 고찰하였다. Bench scale PFBC에서 석탁을 연소하는 동안에 탈황제로 식회석을 사용하였으며, 배가스의 배출특성을 조사함에 있어서 SO_2의 제어에 주안점을 두었다. 석탁은 강원도 태백지역에서 채탄된 무연탄이고, 석회석은 강원도 삼척지역에서 얻은 것이다. 실험장치는 층 직경 0.17m, freeboard 직경 0.25m이고, 총 높이가 5m로 이루어졌다. 실험은 운전압력(1-6 atm), 운전온도(850-950℃), 과잉공기(10-30%), Ca/S 몰비(0.8-4.8)의 조건으로 수행하였다. 결과적으로 최대 탈황율을 보인 층(bed)온도는 1, 2 기압일 때 850℃, 4 기압일때 900℃, 6 기압일 때 950℃로 나타났다. 또 탈황율은 모든 실험조건에서 운전압력, Ca/s 몰비, 과잉공기가 증가함에 따라 증가하였다. 국내무연탄의 가압유동충연소시 안정적인 SO_2의 배출을 위하여 각각의 운전압력에서 적정한 Ca/S 몰비는 2 기압 이하일때 Ca/S≥4.8, 4기압일 때 Ca/S=4.8, 6 기압 이상일때 Ca/S≤4.8를 보였다. This study was to investigate the SO_2 emission with Korean anthracite in a PFBC (Pressurized Fluidized Bed Combustor). This work focuses on the control of SO_2, one of the severe air pollutants in flue gas, emission characteristics by injecting sorbent during the combustion of coal in a bench scale PFBC. The coal and limestone used in this work were Taeback anthracite and Samchuck limestone, respectively, in Korea. The effects of operation parameters such as pressure (1-6 atm), bed temperature (850-950℃), excess air ratio(10-30%), and Ca/S mole(0.8-4.8) on desulfurization was investigated in PFBC(0.17m of bed diamether, 0.25m of freeboard diameter and 5.0m height). The bed temperature showing maximum sulfur capture increased from 850℃ at 1 and 2 atm. to 950℃ at 6 atm. with 10% of excess air ratio. Sulfur capture increased as excess air ratio increased at all experimental condition. Both the sulfur capture and the temperature showing maximum sulfur capture increased as operation pressure increased. It was recognized that Ca/S mole ratio higher than 4.8 was needed below 2 atm. and lower Ca/S mole ratio than 4.8 was needed at 4 and 6 atm. for the stable SO_2 emission in combustion of Korean anthracite.

공기재생용 고온건식탈황제의 가압유동층 반응기에서의 사이클 성능실험

조성호,이봉희,이중범,류청걸,진경태,이창근 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.2

고온고압 기포유동층 반응기에서 분무건조기로 성형제조한 아연계 탈황제(ZAC C)에 대하여 총 6회 황화-재생 반복실험을 500℃, 5atm 조건에서 수행하였다. 1% H_2S를 포함한 석탄모사가스를 반응기에 주입하여 황화반응을 시킨 결과 배출가스 중 H_2S 농도는 10ppmv 이하로 유지되었다. ZAC C의 황흡수력은 6회 황화반응 동안 각각 11.1, 10.9, 11.1, 11.1, 10.9, 10.5g S/100g sorbent으로 유지되어 초기 황흡수력을 유지하였다. 공기를 이용한 500℃ 재생반응에서 배출되는 SO_2의 최대농도는 양론적으로 이론값과 일치하였다. 재생반응에서 탈황제 층의 온도는 발열반응에 의해 500℃에서 최대 750℃까지 상승하였다. 연속 70시간 동안 유동층 반응기내에서 실시된 ZAC C 탈황제의 비산되어 유출된 양은 1.07%이고, 실험 후 탈황제의 크기와 조직특성의 변화도 적었다. 고온고압반응기 multi-cyclone 실험결과 ZAC C 탈황제는 이론 황흡수력의 50% 이상을 유지하였고, 공기를 사용한 500℃의 재생반응이 원활하고 완전히 이루어졌고, 황산염생성과 같은 부반응이 없었다. Two desulfurization-regeneration experiments for a spray-dried zinc-based sorbent(ZAC C) were performed at 500℃ and 5 atm in a fluidized-bed reactor(ID 0.097㎜) facility. The H_S concentration after each desulfurization run was maintained below 10 ppmv from a simulated coal gas of 1% H_2S. The estimated sulfur absorption capacities of ZAC C sorbent were 11.1, 10.9, 11.1, 11.1, 10.9, 10.5 g S/100g sorbent, and the sorption capacity of sorbent was maintained in spite of six times sorption experiments. The maximum SO_2 concentration in regeneration effluent gas agreed with a stoichiometric value of 500℃(ca. 14vol%). In regeneration run, the peak temperature of sorbent bed in the reactor reached up to 750 due to the vigorous exothermicity of regeneration reaction with neat air. While entrainment rate for 70h continuous run in fluidized-bed reactor is 1.07%, the size and the textural properties of ZAC C sorbent also show a little change. Multi-cycle tests in fluidized-bed show that ZAC C sorbent maintains over 50% of its theoretical sorption capacity during 70h run and regeneration reaction undergoes smoothly and completely without side reactions such as sulfate formation.

The effect of noncondensable gas on heat transfer in the preheater of the sewage sludge drying system

Gyoung Tae Jin,Young Cheol Park,Joeng-Geun Kim,Sang-Ho Lee,Jong-Ho Moon,Seung-Yong Lee,Sang Il Choi 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.7

We used a shell-and-tube type preheater to investigate the effect of noncondensable gas on heat transfer. In the preheater of the drying system, heat is exchanged between steam-air mixed gas which is dryer outlet gas and sewage sludge. To evaluate the performances of the preheater, water was first used in the tube-side material instead of sewage sludge and steam-air mixed gas in the shell-side material. The test variables were as follows: mixed gas inlet temperatures range from 95 to 120 oC; inlet air content, mair/msteam from 55 to 83%; tube-side water flow rate from 42to 62 kg/h. The shell-side heat transfer coefficient varied from 150 to 550W/m2K, which corresponds to the amount of noncondensable gas in the steam-air mixed gas and the overall heat transfer coefficient varied from 60 to 210W/m2K. Using sewage sludge as a tube-side material the overall heat transfer coefficient varied from 60 to 130W/m2K and the outlet temperature of sewage sludge was above 90 oC, which is high enough for reducing energy consumption in the dryer by preheating the sewage sludge.

Dual roles of a variable number of tandem repeat polymorphism in the TERT gene in lung cancer

Jin, Guang,Yoo, Seung Soo,Cho, Sukki,Jeon, Hyo-Sung,Lee, Won-Kee,Kang, Hyo-Gyoung,Choi, Yi Young,Choi, Jin Eun,Cha, Sung-Ick,Lee, Eung Bae,Kim, Chang Ho,Jung, Tae Hoon,Kim, Young Tae,Park, Jae Yong Wiley (Blackwell Publishing) 2011 CANCER SCIENCE Vol.102 No.1

Hydrogen production in fluidized bed by chemical-looping cycle

Gyoung Tae Jin,Ho-Jung Ryu,Sung-Ho Jo,Seung-Yong Lee,Sung Real Son,Sang Done Kim 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.3

Characterization and application of oviductal epithelial cells in vitro in Gallus domesticus.

Jung, Jin Gyoung,Park, Tae Sub,Kim, Jin Nam,Han, Beom Ku,Lee, Seon Duk,Song, Gwonhwa,Han, Jae Yong Society for the Study of Reproduction [etc.] 2011 BIOLOGY OF REPRODUCTION Vol.85 No.4

<P>Chicken oviductal epithelium produces large quantities of egg white protein in daily cycles. In this study, we cultured and characterized oviductal epithelial cells (OECs) from juvenile (10-wk-old) chickens and from actively laying (30-wk-old) hens. The juvenile OECs were maintained over passage 25 and were positive for toluidine blue, lectin-ConA, HPA, UEA-1, WFA, WGA, anti-OVA, anti-ESR1, and anti-PGR, whereas the adult OECs were cultured over passage 6 and were positive for toluidine blue, periodic acid-Schiff, lectin-ConA, WFA, WGA, anti-OVA, anti-ESR1, and anti-PGR. To investigate the optimal concentration of steroid hormones for inducing egg white protein genes in vitro, we examined the effects of estrogen, diethylstilbestrol, progesterone, and corticosterone on OECs. Results showed that oviduct-specific levels of avidin, ovalbumin, ovomucin, lysozyme, ESR1, and PGR gene expression were significantly elevated in steroid hormone-treated OECs compared with those of untreated cells (P < 0.05). Ovalbumin protein was also secreted into culture medium from hormone-treated OECs. In addition, to examine the application of OECs for avian transgenesis, we introduced human thrombopoietin (THPO)-expressing lentiviral vector controlled by a 3.5-kb ovalbumin promoter into cultured OECs, and THPO expression was significantly induced with diethylstilbestrol or progesterone in juvenile OECs (P < 0.05) and in adult OECs (P < 0.05). In conclusion, these data demonstrate the potential of cultured OECs as a model system for providing a better understanding of the regulation of gene expression and for the production of an avian transgenic bioreactor.</P>

Effects of cadmium, copper, chromium, nickel, silver, and zinc on the embryonic development of the starfish, Asterias amurensis

Tae-Kwon Ryu,Chang-Hoon Lee,Chan-Gyoung Sung,Jin-Young Seo,Gi-Myung Han,Jin-Woo Choi 환경독성보건학회 2004 한국독성학회 심포지움 및 학술발표회 Vol.- No.-