• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.880-883
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• 2009

석탄가스화복합발전(IGCC) 시스템에서 합성가스 중에 포함된 황화수소($H_2S$)는 후단의 가스 터빈과 같은 장치의 부식을 방지하고, 합성가스를 이용하는 연료전지 등의 연계 공정에서 요구하는 수준에 맞추어 정제되어야 한다. 본 연구에서는 $H_2S$ 정제공정 추가에 따른 IGCC 시스템의 효율저하를 최소화하기 위하여 고온고압에서 사용가능한 탈황제를 분무건조법을 이용하여 제조하고 제조된 탈황제에 대해 물성 및 황 흡수능 시험을 실시하였다. 형상, 내마모도, 평균입자크기, 충진밀도와 함께 제조된 탈황제가 적용되는 유동층 공정에 적합한 강도를 보유하는지 여부를 미국표준시험방법에 의하여 측정하였다. 황 흡수능은 열중량분석기를 반응기로 사용하여 모사 합성 가스 분위기에서 측정하였다. 분무건조 성형된 탈황제의 일부가 구형이 아닌 타원형 또는 도넛 형태를 나타내고 있어 형상 개선을 위한 제조방법 개선이 필요한 것으로 나타났다. 제조된 탈황제는 기공도가 65% 이상으로 macropore가 기공부피의 대부분을, mesopore가 비표면적의 대부분을 제공하고 있었다. 소성온도를 650 $^{\circ}C$에서 750 $^{\circ}C$로 증가시킴에 따라 대체로 강도가 감소하는 경향을 나타내었다. 열중량분석기로 측정된 황 흡수능은 약 10 wt%로 나타났다. 제조된 탈황제 중 일부는 유동층 공정에 적합한 물성을 보유하고 있었으며 반응성 또한 기존에 개발된 탈황제에 버금가는 성능을 나타내어 향후 공정 적용이 가능할 것으로 분석되었다.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.47-53
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• 2007

The aim of this study is to research applicable possibility or Dry Sorbent Injection Technique(DSI) in sox removal process using Computational Fluid Dynamics(CFD) software package. It will be applied for 500MW in capacity coal-fired thermal power plant operated by South Korea N. Power Co., Ltd. The DSI process is adapted between a preheater and an EP process in the technological assembly. The numerical analysis performs in predicting and optimizing of DSI process's characteristics, which consists of structure of duct, position of injection nozzles, injection speed, and dispersion of sorbent. Computing results are shown that degree of sorbent dispersion depends on structure of duct and position of injection nozzles strongly. The highest dispersion efficiency was obtained when we set a Lobed-plate inside the duct and 6 injection nozzles on the duct(4 injection nozzles at the corners and 2 injection nozzles on upper and under walls as a rectangle duct shape). We also know that change of injection speed of sorbent doesn't have an large effect on the sorbent dispersion but it can effect to drop pressure.

• Resources Recycling
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• v.27 no.5
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• pp.49-53
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• 2018

In developing an optimum steelmaking process, the purity of the product, environmental impact, capability and cost of the process should be considered. Desulfurization of molten iron is conducted during preliminary treatment stage before converter operation. Although fluorite is added as a desulfurizing agent in CaO and $CaCO_3$ based agents, the concentration of fluorine in slag is strictly regulated. In order to develop desulfurizing agent without fluorine, CaO was mixed with Al dross and ladle slag containing alumina. The characteristics and desulfurizing capacity of the CaO based desulfurizing agent thus prepared were tested by varying temperature of Kanvara Reactor. Our results showed that the desulfurizing capacity of the samples prepared in this work was found to be similar to that of the traditional desulfurizing agents with fluorine.

• Resources Recycling
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• v.25 no.5
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• pp.14-27
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• 2016

Theoretical reviews of integrated gasification combined cycle one of the clean coal technologies and trends in the study and technology development for high temperature desulfurization sorbents were investigated. Reactivity, durability and abrasion resistance is an important key for development of high temperature desulfurization sorbents, the kind of things include calcium, zinc, manganese, iron and copper-based sorbents. Current status of high temperature desulfurization sorbents, manufacturing techniques of zinc-based sorbent in advanced countries has commercialized. In case of Korea, various research studies are underway to commercialize the Zn and non Zn-based high temperature desulfurization sorbents to cheaper and superior capability using various supports.

• 한국연소학회:학술대회논문집
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• 2002.06a
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• pp.237-246
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• 2002

가압유동층연소로(bed dia. 0.17m, freeboard dia. 0.25, total height 5m)에서 국내무연탄을 연소시켜 이에 대한 탈황특성을 고찰하였다. 실험은 압력($2{\sim}6atm$), 요동층온도(($850{\sim}950^{\circ}C$), 과잉공기(10, 20, 30,%)등의 조건과, 탈황을 위한 Ca/S몰비(($0.8{\sim}4.8$)가 탈황특성에 미치는 영향을 고찰하였다. 결과적으로, 본 연구의 실험범위에서 연소효율은 $80{\sim}99%$를 보였고, 연소온도, 압력 그리고 과잉공기가 증가 할수록 증가하였다. 배가스중의 $SO_2$배출농도는 압력, Ca/S몰비가 증가함에 따라 감소하였다. 탈황율은 상압에서 층(bed)온도의 증가에 따라 감소하였다. 운전압력이 증가함에 따라 탈황율의 감소폭이 둔화되었다. 과잉공기가 증가함에 따라 탈황율은 증가하는 경향을 나타냈다. 각각의 운전압력에서 과잉공기의 증가에 따라 약 10%의 증가폭을 보였다. 국내무연탄을 연소하는 경우 운전압력 4atm일 때 Ca/S몰비는 4이상 주입하여야 하고, 6atm일 때 Ca/S 몰비가 2.5이상주입하여야 150ppm이하를 보여 배출규제치를 만족하는 것을 보였다.

• Resources Recycling
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• v.24 no.6
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• pp.17-23
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• 2015

Flue gas desulfurization(FGD) is the technique to remove $SO_2$ gas from stack gases of coal-fired plants. Many researcher have studied to replace the desulfurizing agent because FGD systems use a lot of limestone and energy. In this study, we use the limestone sludge which is a by-product of steel industry in order to replace desulfurizing agent of FGD system by control the particle size of limestone sludge. And desulfurization performance test is implemented by investigating $SO_2$ gas removal properties upon the characteristic of the limestone sludge with various particle size.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.278-285
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• 2005

In the present work, a reaction of sulfur removal and simulation of desulfurization based on the grain model and two-phase theory were studied using natural manganese ore (NMO) as a sorbent in a continuous fluidized bed reactor. The effect of desulfurization was investigated through the grain model considered the change of pore structure as a function of desulfurization time, particle size of NMO, and diffusion velocity of $SO_2$ in the pores. Among these parameters, the diffusion of $SO_2$ in the pores of NMO was the most important factor. Moreover, the reaction of sulfur removal and desulfurization in a continuous fluidized bed reactor using NMO as a sorbent could be well predict through the grain model and two-phase theory, respectively.

• Economic and Environmental Geology
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• v.52 no.2
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• pp.119-128
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• 2019

About 300,000 tones of oyster shell are annually produced in Korea and, thus, a massive recycling plan is required. Many desulfurizing studies using oyster shells with chemical composition of $CaCO_3$ have been performed so far; however, most of them have focused on dry desulfurization. This study investigates the possibility of using oyster shells for wet desulfurization after calcination. For this, a simulated wet desulfurization facility of spray type was devised and compared the SOx-stripping characteristics of calcined oyster shell with those of limestone. The calcined oyster shell slurry indicate a better desulfurizability than the slurries of raw shell or limestone because the oyster shell transformed to a more reactive phase ($Ca(OH)_2$) by the calcination and hydration. Because of this reason, when the calcined oyster shell slurries were used, the reaction residue showed the higher gypsum ($CaSO_4{\cdot}2H_2O$) contents than any other cases. In the continuous desulfurization experiments, calcined oyster shell slurry showed a wider pH variation than limestone or raw oyster shell slurries, another clear indication of high reactivity of calcined oyster shells for $SO_2$ absorption. Our study also shows that the efficiency of wet desulfurization can be improved by the use of calcined oyster shells.

• Resources Recycling
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• v.24 no.3
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• pp.59-65
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• 2015

Recycling of vulcanized rubber products is a serious problem in the world. A quantity of generated waste tires becomes much more and more because of increasing demands on automobiles, resulted in the cause of serious secondary pollution by sulfur component that is crosslinked to incineration or landfill. In addition, crosslinked surfur is used to interfere with the binding of the raw material rubber. In this study, we analyzed the degree of devulcanization by the chemical devulcanization. Devulcanization ratio of the samples were systematically analysed by variables such as time and temperature. In addition, the effect of swelling method as a pre-treatment process was also measured. A rubber specimen was deepened in a organic 2-buthanol solutions during various times of 1 ~ 5 hrs at 100, 150, $200^{\circ}C$ respectively, then to calculate the crosslink density and the number average molecular weight by using a parallel expansion process, which showed devulcanization degree of analyzed samples quantitatively. Also, the mechanical properties were measured with the samples prepared by using a hot press.

• Clean Technology
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• v.7 no.1
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• pp.81-88
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• 2001

Limestone has been used as absorbent in the FGD(Flue Gas Desulfurization) system, the DeSOx system of thermal power plant. This study investigated the desulfurization characteristics of the two different limestones, 325mesh and 200mesh particle size. Experimental analysis showed that the dissolving rate of limestone became much slower as the particle size increased. But the desulfurization efficiency depended on the L/G(liquid/gas) ratio and slurry pH regardless of the limestone particle size. The quality of gypsum produced in the FGD process increased as the limestone particle size or the slurry pH decreased. To reduce the cost of absorbent, the mixed limestone which were composed of 200 and 325mesh limestone with 5 different ratios were tested.