• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.225-230
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• 2013

A new heteropolyanion-based ionic ($[Hmim]_5PMo_{10}V_2O_{40}$) was synthesized by the reaction of molybdovanadophosphoric acid ($H_5PMo_{10}O_{40}$) with N-methylimidazole. [$[Hmim]_5PMo_{10}V_2O_{40}$ showed a high catalytic activity in the oxidative desulfurization of sulfur-containing compounds in 1-methylimidazolium tetrafluoroborate ($[Hmim]BF_4$) ionic liquid using 30% aqueous $H_2O_2$ as the oxidant. The catalytic system was of high activity, simplified workup and flexible recyclability. The catalytic oxidation reactivity of sulfur-containing compounds decreased in the order dibenzothiophene (DBT) > 4,6-dimethyldibenzothiophene (4,6-DMDBT) > benzothiophene (BT). The influences of various parameters including reaction time (t) and temperature (T), catalyst dosage, and oxidant to sulfur molar ratio n(O)/n(S) on the desulfurization of model oil were investigated in details. 99.1% of DBT conversion in the model oil was achieved at atmospheric pressure under the optimal conditions: n(O)/n(S) = 4:1, $60^{\circ}C$, 100 min and molar ratio of catalyst to sulfur of 0.062. The ionic liquid can be recycled six times without significant decrease in activity.

• 한국환경보건학회지
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• 제36권2호
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• pp.136-140
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• 2010

The integrated gasification combined cycle (IGCC) is one of the most promising proposed processes for advanced electric power generation that is likely to replace conventional coal combustion. This emerging technology will not only improve considerably the thermal efficiency but also reduce or eliminate the environmentally adverse effects normally associated with coal combustion. The IGCC process gasifies coal under reducing conditions with essentially all the sulfur existing in the form of hydrogen sulfide ($H_2S$) in the product fuel gas. The need to remove $H_2S$ from coal derived fuel gases is a significant concern which stems from stringent government regulations and also, from a technical point of view and a need to protect turbines from corrosion. The waste seashells were used for the removal of hydrogen sulfide from a hot gas stream. The sulphidation of waste seashells with $H_2S$ was studied in a thermogravimetric analyzer at temperature between $600^{\circ}C$ and $800^{\circ}C$. The desulfurization performance of the waste seashell sorbents was experimentally tested in a fixed bed reactor system. Sulfidation experiments performed under reaction conditions similar to those at the exit of a coal gasifier showed that preparation procedure and technique, the type and the amount of seashell, and the size of the seashell affects the $H_2S$ removal capacity of the sorbents. The pore structure of fresh and sulfided seashell sorbents was analyzed using mercury porosimetry, nitrogen adsorption, and scanning electronmicroscopy.

• Korean Chemical Engineering Research
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• 제47권4호
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• pp.512-517
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• 2009

순산소 연소에서 $SO_2$ 농도는 배가스의 재순환으로 인해 기존의 공기연소에 비해 3배 이상 높게 나타나고, $CO_2$ 농도와 $SO_2$ 농도가 높기 때문에 탈황현상이 기존의 공기 연소와는 다르게 나타난다. 본 연구에서는 순산소 연소조건에서 로내탈황 특성을 알아보기 위해 Drop Tube Furnace(DTF)를 이용하여, 반응온도, 유입 $SO_2$ 농도 그리고 Ca/S 비 등의 운전변수에 따른 $SO_2$ 제거효율을 측정하였으며 수분의 영향에 대해서도 알아보았다. 반응온도, 유입 $SO_2$ 농도 그리고 Ca/S 비가 증가함에 따라 $SO_2$ 제거효율은 증가하였고 유입가스 내 수분이 존재할 경우 $SO_2$ 제거효율은 약 4~6% 증가하는 것으로 나타났다.

• Environmental Analysis Health and Toxicology
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• 제14권3호
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• pp.121-126
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• 1999

The present paper describes a study of the photochemical kinetics and its oxidation mechanism of DBT. The photolysis of DBT in aqueous solution media have shown to have significant oxidation activities for the photolytic desulfurization of DBT. The oxidation effect was more pronounced in 4 % NaCl solution. A mechanism was proposed that the desulfurization process arise from the substution of sulfur by the hydroxyl radicals in different aqueous medium.

• 설비공학논문집
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• 제12권2호
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• pp.120-130
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• 2000

A flow uniformity in a duct cooler of duct system of FGD(Flue Gas Desulfurization) linking a reheater and a absorber has been investigated in the present study. For this purpose, the flow characteristics according to the geometry of a vertical and horizontal vane in a curved duct of the duct system has been examined with the aid of a numerical simulation. The results indicate that the vertical vane with a little deflection toward a recirculation region makes the flow distribution in the duct cooler more uniform than that without deflection, and horizontal vane does not effect the change of the flow distribution for an angle of inclination. The mean flow uniform factor shows its maximum for duct system without the vane(case NP) and its minimum for the vertical vane with a little deflection(case P-0.8-0) .

• 자원환경지질
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• 제52권2호
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• pp.119-128
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• 2019

국내에서는 연간 약 30만 톤 내외의 굴패각이 발생되고 있어, 이를 대규모로 활용할 수 있는 적절한 방안이 요구되고 있다. $CaCO_3$가 주성분인 굴패각을 탈황재료로 사용하는 연구들이 많이 진행되어 왔으나, 지금까지는 주로 건식탈황을 대상으로 한 것이었다. 본 연구에서는 굴패각을 소성하여 습식탈황재료로 활용하는 가능성에 대하여 고찰하였다. 이를 위하여 습식배연탈황공정의 하나인 spray type 방식의 모사탈황장치를 제작하여 소성 굴패각의 탈황특성을 석회석과 비교하였다. 연구결과, 소성 굴패각은 석회석이나 소성하지 않은 굴패각에 비하여 우수한 $SO_2$ 흡수능을 보였다. 이는 굴패각이 소성 및 수화반응을 통해 상대적으로 반응성이 높은 형태($Ca(OH)_2$)로 전환되었기 때문이다. 이로 인하여 반응잔류물 중에 석고($CaSO_4{\cdot}2H_2O$)의 함량이 다른 경우에 비하여 높게 나타났다. 본 연구의 연속탈황실험에서는 소성 굴패각이 석회석에 비하여 큰 pH 변동폭을 보였으며, 석회석과 소성 굴패각을 혼합하여 수행된 탈황실험에서도 소성 굴패각의 혼합비율이 증가됨에 따라 pH변동폭이 커지는 결과를 보였다. 이러한 현상은 소성 굴패각의 $SO_2$ 흡수 반응성이 큰 것을 잘 보여주는 것이다. 본 연구결과는 소성 굴패각을 습식탈황에 이용할 경우 탈황효율을 크게 향상시킬 수 있음도 보여준다.

• 한국대기환경학회지
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• 제8권4호
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• pp.262-268
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• 1992

The trend of international concerns on environmental conservation and domestic demand of ambient air quality improvement, specially on sulfur dioxide level has resulted in the establishment of mid-term strategy of environmental improvement and stepwise strengthening of emission regulations in this decade in Korea. Development of flue gas desulfurization(FGD) process is becoming an essential task to be accomplished especially for the power plants and large industrial facilities. This study is an initial stage researc focusing on the mass transfer principles in wet type FGD process and the effects of operating variables of a jet bubbling scrubber utilizing limestone slurry on sulfur dioxide removal efficiency. Experimental results showed this type of scrubbing system has some advantages in terms of mass transfer mechanism and removal efficiency. More rigorous research is needed for the reaction system and the comparison with existing FGD processess for the possible development of a process which is compatative in view of installation cost and treatment of by-products.

• 자원리싸이클링
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• 제24권6호
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• pp.17-23
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• 2015

배연탈황 기술은 화력발전소의 연소가스에서 발생하는 $SO_2$를 제거하는 기술이다. 발전소에서는 주로 석회석을 이용한 습식 배연탈황공정을 적용하고 있으나, 천연자원인 석회석의 고갈 및 높은 운전동력 소비 등의 문제로 석회석을 대체할 수 있는 흡수제 개발에 매진하고 있다. 따라서 본 연구에서는 제철소에서 발생하는 석회석 슬러지를 흡수제로 적용하기 위해 석회석 슬러지의 입도분포에 따른 탈황성능을 검토하고자 하였다. 탈황효율 검토방법으로는 입도에 따른 석회석 슬러지의 물리 화학적 특성 검토 및 $SO_2$가스제거시험 등을 시행하였다.

• 한국세라믹학회지
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• 제51권6호
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• pp.575-583
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• 2014

The flue gas desulfurization (FGD) process is currently the most effective process utilized to remove sulfur dioxide from stack gases of coal-fired plants. However, FGD systems use a lot of limestone as desulfurizing agent. In this study, we use limestone sludge, which is a by-product of the steel industry, to replace the desulfurizing agent of the FGD system. The limestone particle size is found to be unrelated to the desulfurizing rate; the gypsum purity, however, is related. Limestone sludge mixes with limestone slurry delivered at a constant rate in a desulfurizing agent with organic acid are expected to lead to a high desulfurization efficiency and high quality by-product (gypsum).

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1995년도 특별강연 및 추계학술발표 개요집
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• pp.157-159
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• 1995