• 열처리공학회지
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• 제6권4호
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• pp.243-248
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• 1993

A Circulating Fluidized-Bed (CFB) with an internal nozzle and a partition wall was proposed. The technique of fluidization is related to operations first used commercially in the fields of metallurgical and mechanical engineering such as the heat treatment of metals and power station combustors. In the modified CFB, an internal nozzle and a partition wall were additionally set in the main bed. This cold mode CFB apparatus made of acrylic resin; the main bed is 1,500mm high and 100mm in the inner diameter, the internal nozzle is 130mm high and 10mm in the inner diameter, and the partition wall is 7mm thick and 100mm in the diameter. Glass beads of $89{\mu}m$ in the mean diameter were employed as bed materials.

• 상하수도학회지
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• 제14권2호
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• pp.164-173
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• 2000

Fluoridation of drinking water to a level of about 0.8mg/l (below 1.5mg/l) for reducing the incidence of tooth decay is recommended. However, concerns about potential problems of unknown effects and overdosing hinders the fluoridation. This study describes the work performed to obtain information on the behavior of fluoride under various conditions in the process of water fluoridation. Effects of water treatment chemicals, water treatment unit, and water distribution on water fluoridation were investigated at both lab and an actual water treatment plant. Residual fluoride concentration was not affected by lime and chlorine dosage up to 20mg/l. Flocculation with PAC slightly decreased the residual fluoride concentration as PAC dosage increased. Average fluoride concentration of 0.87mg/l at an intake basin was decreased to 0.83mg/l by sedimentation, 0.81mg/l by dual media(sand+anthracite) filtration, and 0.79mg/l by granular activated carbon filtration in the water treatment plant.

• 한국환경보건학회지
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• 제26권4호
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• pp.38-44
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• 2000

Compared to other waste, waste tire has much discharge quantity and calorie. When we use waste heat from waste tire, it can be definitely better substitute energy than coal and anthracite in high oil price age. To use as a basic data for providing low cost and highly effective heating system, following conclusion was founded. Annual waste tire production was 19,596 million in 1999, Recycling ratio was almost 55% and more than 8.78 million was stored. Waste tire has lower than 1.5% sulfur contain ratio which is resource of an pollution, So it is a waste fuel which can be combustion based on current exhaust standard value without any extra SOx exclusion materials. Waste tire has 9,256Kcal/kg calorific value and it is higher than waste rubber, waste rubber, waste energy as same as B-C oil. When primary and second air quantity was 1.6, 8.0 Nm$^3$/min, dry gas production time was 270min and total combustion time was 360 min. In the SOx, NOx, HC of air pollution material density were lower than exhaust standard value at the back of cyclone and dusty than exhaust standard value without dust collector.

• 전기의세계
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• 제16권1호
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• pp.19-28
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• 1967

Indigenous energy resources available in Korea are limited to the three major resources such as Korean anthracite, hydraulic potential and wood and straws. As reported in various reports concerning energy problem in Korea, unfortunately these three major resources are not only poor in quality but also limited in quantity. The amount of energy to be imported, which will be increased at a considerably high rate by years due to the shortage in the supply by domertic sources against the demand, is studied in the view-pint of sound and logical energy dependence upon the external sources. What would occur, if the imported energy would be exclusively limited to an energy source only, has an enough reason to be paid a significant consideration. As a result, the feasibility is discarded in favour of nuclear power plants after an extensive prospect for electric power development plan covering more than coming thirty years, i.e., up to the year of 2,000 A.D. In briefing, this paper indicates that a measures to accomodate as large amount of nuclear power plants as possible in the electric power system is not only inevitable for a sound solution of the severe energy problem with which Korea is to be confronted but also leads to the national benefit.

• 한국안전학회지
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• 제12권2호
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• pp.111-118
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• 1997

Granulation procedure was carried out in a 0.109m I. D., 1.8m height fluidized bed coal combustor of the multi-sized particles. The domestic anthracite with heating value 3240kcal/kg was used. Granulation of fine coal particles and fluidizing characteristics were investigated by the pressure fluctuation properties such as mean pressure, standard deviation of pressure fluctuation and power spectrum distribution. Defluidization state and granulation mechanism were also studied by the various analysis. It was found that the conversion efficiency in the elutriated stream was increased by the coalescence of fine coal particles. Defluidization and pressure fluctuation properties were interrelated and this result was indication of the capabilities of pressure fluctuation properties analysis in the diagnostics of fluidizing state.

• 자원리싸이클링
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• 제4권1호
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• pp.20-24
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• 1995

어룡무연탄의 수력채탄시 산출될 수 있는 -200mesh의 분탄과 물위 슬러리를 COM(Coal Oil Mixture)화에 의하여 탈수시킴에 있어서 고분자응집제를 병행한 효과를 상징액의 빛 투과율로 조사하였다. 경유와 음이온 고분자응집제(A110)를 같이 사용하면 경유로만 응집시킬 때보다 낮은 교반속도에서도 COM이 형성되며 대단히 높은 상징액의 청정도를 보인다. 이때의 고분자응집제의 소요농도는 100g/t이고 경유의 소요량은 석탄량의 10%정도이다.

• Nuclear Engineering and Technology
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• 제34권1호
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• pp.9-21
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• 2002

Recently each domestic NPP has achieved zero release in liquid effluent activity. However, when looking back past experiences in world nuclear power operation, it is thought that another maximum activity reduction in the released liquid effluent just prior to falling it into environment, if possible, will bring a good effect in PA viewpoint. As the intent of applying the safety concept of diversity to conducting the above activity reduction measure, a scheme passing that effluent through the Deposition Bed just before discharging it into ocean environment was divised. Both Zeolite and ＂the mixed ＂Anthracite-sand＂ were derived as the main activity adsorption medium used in the Deposition Bed, and the schematic drawings of this Bed were presented.

• 한국토양비료학회지
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• 제25권2호
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• pp.143-148
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• 1992

석탄회(石炭灰) 과량시용(過量施用)은 콩의 발아(發芽) 및 초기생육(初期生育)에 해로운 영향(影響)을 주었으며 특히 유연탄회(有煙炭灰) 10MT/10a 이상(以上) 시용(施用)한 경우는 잎에 뚜렷한 독증(毒症)을 나타냈고 생육후반기(生育後半期)까지도 콩의 생장(生長)에 해로운 효과를 주었다. 그러나 초기생육 단계(段階)에서의 해작용(害作用)은 생육이 진전(進展)되면서 점차로 감소(減少)되어 없어지고 오히려 생육을 증진(增進)시키는 효과를 나타내어 무연탄회(無煙炭灰)의 경우 시용(施用) 수준(水準)을 15MT/10a까지 증가(增加)시킬수록 초장 및 건물중(乾物重)이 증가되었다. 그러나 유연탄회(有煙炭灰)의 경우 10MT/10a 이하(以下) 수준(水準)에서는 무연탄회(無煙炭灰)의 경우와 마찬가지로 생육후반기(生育後半期)로 갈수록 해(害)작용이 없어지며 콩의 생육(生育)에 양호한 영향을 주었지만, 10MT/10a이상(以上) 시용(施用)했을 경우는 생육후기(生育後期)에도 잎에 붉은 반점이 생기며 말라 버리는 증상(症狀)이 발현(發現)되었다. 석탄회(石炭灰)의 시용(施用)은 토양 pH를 증가(增加)시키는 경향(傾向)을 보였으며 무연탄회(無煙炭灰)보다는 유연탄회(有煙炭灰)에서 그 효과가 더 현저(顯著)하였다. 석탄회(石炭灰)의 시용(施用)에 의한 토양 pH 교정효과는 토양중 유효인산(有效燐酸)의 함량을 증대(增大)시켰으며 이는 콩의 생장(生長) 및 수량(收量)을 증대 시키는데 기여(寄與)한 것으로 생각된다. 종합적(綜合的)으로 고찰(考察)해 볼 때 석탄회(石炭灰)의 사용은 토양(土壤)의 물이화학성(物理化學性)을 개선(改善)시켜 콩의 생육(生育)을 증진(增進)시키는 것으로 나타났으며 콩의 생장촉진(生長促進)을 위한 석탄회(石炭灰)의 적정(適正) 시용수준(施用水準)은 무연탄회(無煙炭灰)의 경우 5MT-10MT/10a, 유연탄회(有煙炭灰)의 경우는 5MT/10a 정도(程度)가 바람직할 것으로 생각된다.

• 한국토양비료학회지
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• 제27권2호
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• pp.72-77
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• 1994

무연탄회(無煙炭灰)와 유연탄회(有煙炭灰)를 논토양(土壤)의 식양토(植壤土)와 사양토(砂壤土)에 각 12톤/10a씩 3('91~'93)연간(年間) 연용(連用)하고, 밭 토양(土壤)도 식양토(植壤土)와 사양토(砂壤土)에 각 9톤/10a씩 3년('91~'93)간 연용하면서 벼와 콩을 각각 재배(栽培)한 후에 토양(土壤)을 I, II, III층으로 구분 채취(採取)하여 중금속(重金屬)인 Cd, Cu, Pb, Zn, Ni, Cr, Fe, Mn함량(含量)을 조사(調査)한 결과(結果)는 다음과 같다 1. 토양(土壤) 깊이별(別) 중금속(重金屬) 함량(含量)은 표층(表層)이 가장 높고 토심이 깊어질수록 낮았으며 석탄회(石炭灰) 시용량(施用量) 증가(增加)에 따라서 논 밭 모두 표층(表層)에서만 일부 성분이 증가(增加) 경향이 있고 심층(深層)은 일정한 경향이 없었으며, 토성(土性)에 따라서도 일정한 경향이 없었다. 2. 무연탄회(無煙炭灰)는 논토양(土壤)에서는 Cd, Cu, Zn, Cr함량(含量)이, 밭토양(土壤)에서는 Cd, Cr함량(含量)이 증가(增加)되었고 그 함량(含量)은 우리나라 평균치(平均値) 또는 평균치(平均値)+표준편차(標準偏差) 범위(範圍)이었다. 3. 유연탄회(有煙炭灰)는 논토양(土壤)에서는 Cd, Zn, Cr함량(含量)이 밭토양(土壤)에서는 Cd, Zn, Cr, Ni함량(含量)이 증가(增加)되는 경향이었고. 그 함량(含量)은 우리나라 평균치(平均値) 또는 평균치(平均値)+표준편차(漂準偏差) 범위(範圍)이었다.

• 공업화학
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• 제9권6호
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• pp.835-841
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• 1998

활성탄제조에 적합한 유연탄과 무연탄을 선정하여 활성탄을 제조하고, 유연탄과 무연탄의 혼합비율을 달리하였을 때 나타나는 물리적 특성을 규명하였다. 유연탄에 무연탄인 Dandong탄을 25, 50, 75 wt.%로 혼합하여 활성탄을 제조할 경우 활성탄 수율은 Dandong탄의 함량 증가에 따라 증가되었으나 겉보기 밀도는 유연탄의 성상에 관계없이 일정하게 나타났고, 흡착력을 나타내는 요오드가는 반대로 감소되었다. Fushun탄과 Dandong탄을 75:25 wt.%로 혼합한 후 활성화조건에 따른 기공특성을 관찰한 결과 기공분포는 활성화온도 $850{\sim}900^{\circ}C$에서 $20{\AA}$ 이하의 미세기공이 발달되었고, $830^{\circ}C$와 $950^{\circ}C$에서는 중간기공이 발달되었다. 또한 제조된 석탄혼합 활성탄의 성능을 고찰하기 위해 상용화된 제품과 실험을 통해 흡착성능을 비교하였는데 경쟁력있는 흡착력을 갖는 것으로 확인되었다. 따라서 활성탄 제조시 탄화 및 활성화 과정에서 여러 가지 조업변수와 원료탄 혼합효과에 의해 그 특성이 달라짐이 확인되었다.