• 한국건축시공학회지
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• 제16권6호
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• pp.497-503
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• 2016

배연탈황석고는 화력발전소에서 연료가 연소되면서 발생된 황산화물을 흡수, 제거하는 공정에서 발생되는 산업 부산물로서 최근 석탄 화력발전소의 배출가스에 관련된 환경규제가 대폭 강화됨에 따라 생산량이 점차 증가하고 있다. 배연탈황석고는 자연에서 얻어지는 형태의 천연석고와 거의 유사한 화학적 특성을 지니기 때문에, 이를 재활용하게 되면, 주로 수입에 의존하는 천연석고의 훌륭한 대체재로서 활용할 수 있다. 본 연구에서는 국내의 보령 화력발전소에서 생산된 배연탈황석고의 화학적 특성을 분석하고, 이를 이용하여 만든 시멘트 페이스트의 물성분석을 통하여, 배연탈황석고의 활용가능성을 평가하고자 하였다. 본 연구의 결과에 따르면, 배연탈황석고는 상당히 높은 순도를 가지며, 천연석고와 물성이 매우 유사한 것으로 나타났다. 또한 이를 적절하게 열처리하게 되면, 압축강도 및 건조수축에서의 개선효과를 얻을 수 있는 것으로 나타났다.

• 한국대기환경학회지
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• 제14권4호
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• pp.273-280
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• 1998

The investigation on the removal of 502 gas fro.In flue gas which causes serious air pollution was made by using a semi dry flue gas desulfurization method. Experiments were carried out as a function of process variables which would affect SO2 removal efficiency. Process variables inclilded SO2 inlet concentration, inlet temperature of simulated flue gas, sorbent weight fraction, and volume flow rate of sorbent slurry. In this study, used sorbent was Ca(OH), and simulated flue gas was prepared by mixing pure SO2 gas with air. Experimental conditions were varied at 140~18$0^{\circ}C$ of inlet temperature of the simulated flue gas, 500~2000ppm of inlet SO2 concentration, 0.4~1.0% of sorbent concentration, and 10~25 mL/min of flow rate of sorbent slurry. Among process variables, inlet concentration of SO2 was found to be the most significant factor to affect SO2 removal efficiency. The concentration of Ca(OH2) had a lower effect on SO2 removal than SO2 inlet concentration removal amount was 0.108, 0.141, 0.153 g SO2/g Ca(OH)2 respectively- As 200 mmol of HNO3 was added into slurry to improve removal efficiency, initial pH was maintained and solubility of slurry increased, so that removal efficiency elevated. Adding over 200 mmol of HNO3 into slurry caused removal efficiency lower. Therefore it could be concluded the optimum was 200 mmol of HNO3 input.

• 환경위생공학
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• 제14권2호
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• pp.84-89
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• 1999

This experiment was performed to develop the new desulfurization process which can eliminate the possibility of generation of the secondary pollutants by regenerating the limestone from the sulfite/sulfate slurry generated from the wet lime/limestone flue gas desulfurization process by treating it with the ammonium hydroxide and carbon dioxide and using it again. In the experiments, regent grade calcium carbonate was dissolved to obtain the 200ml of sample slurry of the concentration of 2.0~0.4 weight percent. After three times of regeneration and desulfurization process, the coefficients of regeneration and desulfurization efficiencies are calculated/measured. The obtained results are that the coefficients of generation of the first. second, and third regenerated calcium carbonate were 90.88, 92.13, and 91.50%, respectively; and the desulfurization efficiencies of those are 93.4, 94.2 and 93.0%, respectively.

• 한국환경과학회지
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• 제22권9호
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• pp.1073-1078
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• 2013

This paper presents the results of the electrochemical treatment of chemical oxygen demand(COD) and total nitrogen(T-N) compounds in the wastewater generated from flue gas desulfurization process by using a lab-scale electrolyzer. With the increase in the applied current from 0.6 Ah/L to 1.2 Ah/L, the COD removal efficiency rapidly increases from 74.5% to 96%, and the T-N removal efficiency slightly increases from 37.2% to 44.9%. Therefore, it is expected that an electrochemical treatment technique will be able to decrease the amount of chemicals used for reducing the COD and T-N in wastewater of the desulfurization process compared to the conventional chemical treatment technique.

• 한국환경보건학회지
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• 제27권4호
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• pp.9-14
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• 2001

This study was performed to develop the modified FGD(Flue Gas Desulfurization) process which can eliminate the possibility of generating secondary pollutants. Limestone was regenerated by adding ammonium hydroxide and carbon dioxide, and reusing it as a absorbent in FGD gypsum Process. A series of the new or modified FGD process which include desulfurization and regeneration limestone from CaSO$_3$. 1/2H20 and CaSO4 . 2H2O, were carried out under various experimental conditions. The results showed that the optimum injection ratio for regeneration of limestone was 0.3 ml/min of CO2 flow rate, 2 ml of NH4OH per 0.01 M of regent grade CaSO4 . 2H20O and the optimum regeneration temperature was 50. The increaser was the number of times of limestone regeneration, the faster was the breakthrough point of desulfurization at the desulfurination process which the regenerated limestone was used. Then the efficiency of desulrurization was decreased. This study can be confirmed the possibility for reuse of regenerated limestone due to the similarity of desulfurization characteries both reagent grade calcium carbonate and regenerated calcium carbonate. Finally, it appeared that the new technology using regenerated 1imestone can be applied to the FGD process.

• 한국세라믹학회지
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• 제53권6호
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• pp.676-681
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• 2016

For the purpose of reducing the amount of limestone, which is used as a desulfurization agent to absorbing $SO_X$ gas in thermal power plants, and to recycle limestone sludge generated from a steel mill, limestone sludge was utilized as a desulfurization agent. In this study, cement, made of flue gas desulfurization (FGD) gypsum obtained in a desulfurization process using limestone sludge, was manufactured then, experiments were conducted to identify the physical properties of the paste and mortar using the cement. The results of the crystal phase and microstructure analyses showed that the hydration product of the manufactured cement was similar to that of ordinary Portland cement. No significant decline of workability or compressive strength was observed for any of the specimens. From the results of the experiment, it was determined that FGD gypsum manufactured from limestone sludge did not influence the physical properties of the cement also, quality change did not occur with the use of limestone sludge in the flue gas desulfurization process.

• 한국환경보건학회지
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• 제29권1호
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• pp.34-42
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• 2003

The objective of this study is to investigate the waste recycling possibility, practicability, economic efficiency and acid gas sorbent use of the hard-shelled mussel. This study is to investigate the hydration/calcination reaction and fixed bed reactor. The physical-chemical characteristics of the hard-shelled mussel were analyzed by ICP SEM-EDX, BET and pore volume. Thus, the results could be summarized as follows; Hard-shelled mussel can be used as iron-manufacture and chemical sorbents considering more than 53.7% of the mussel is lime content. The SO$_2$removal efficiency of the hard-shelled mussel after calcined hydration increased thirty times as a result of the higher pore size, specific surface area and pore volume. Also, the CaO content, pore volume, pore size distribution and specific surface area greatly influenced the SO$_2$ and NOx removal reactivity. The optimum particle diameter average of hard-shelled mussel was $\pm$100 mesh, which was applied to the sorbent on the medium/small scale waste incinerator and flue gas desulfurization processes.

• 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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• 제25권5호
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• pp.44-49
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• 2016

배연탈황기술은 화력발전소에 발생하는 $SO_2$ 가스를 제거하기 위한 효과적인 방법이며, 흡수제로 석회석을 사용하고 있다. 본 연구에서는 천연자원인 석회석의 사용량을 저감하고 산업 폐기물의 재활용을 위해, 제철소에서 발생하는 석회석 슬러지를 흡수제로 사용하고자 하였다. 흡수제 원료의 물리 화학적 특성분석을 실시하였으며, 전처리 설비를 구축하여 석회석 슬러지를 사용한 흡수제를 제조한 후 배연탈황 공정에 적용하였다. 제조 흡수제 적용 결과, $SO_2$ 농도 변화상에서의 경향성은 나타나지 않았으며, 흡수탑에서의 운전 제어를 통해 석회석 슬러지를 흡수제로 사용 가능할 것으로 사료되었다.

• 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).