• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.294-299
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• 2007

Natural gypsum has been used as a soil amendment in the United States. However, flue gas desulfurization (FGD)-gypsum has not traditionally been used for agricultural purpose although it has potential benefit as a soil amendment. To expand use of FGD-gypsum for agricultural purpose, the effect of FGD-gypsum on soil chemical properties was investigated in the field scales. Application rates for this study were 0 (control), 1.1, and 2.2 Mg ha-1 of FGD-gypsum. After two year application, the soil samples were taken to 110 cm depth and sub-sampled at 10 cm intervals. The heavy metal contents in FGD-gypsum were lower than ceiling levels allowed by regulations for land-applied biosolids. Soil pH was not largely affected by FGD-gypsum application. Although degree of calcium (Ca) saturation in surface horizons increases only slightly with respect to the control, there is a clear decrease in exchangeable aluminum (Al). FGD-gypsum clearly increases the soil electrical conductivity (EC) with increasing application rate. Water-soluble Ca and sulfate is increased with FGD-gypsum application and these ions moved to a depth of at least 80 cm after only 2 years. We conclude that surface application of FGD-gypsum can mitigate toxicity of Al and deficiency of Ca in subsoil of acid soil.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.157-164
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• 2016

In this research, based on the condition of using desulfurization gypsum(FGD) as a stimulator for high-volume blast furnace slag cement mortar, sieving and heating process methods of removing activated carbon in FGD were compared with the non-processed FGD and recycled and natural fine aggregates were compared for suitable aggregate to be used. According to the result of experiment, sieving with 0.3mm was more efficient than $500^{\circ}C$ heating for processing the FGD, and recycled fine aggregate showed more favorable result than natural fine aggregate at the FGD content was 5 to 10%. On the other hand, the mortar mixture including recycled fine aggregate had a high drying shrinkage, and absorption ratio, and thus specific limitations on applying recycled fine aggregate should be required.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.303-309
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• 2020

The purpose of this study was to identify the changes in the components of unfermented Gongjin-dan (GD) and fermented Gongjin-dan (FGD) and to confirm whether GD or FGD has an inhibitory effect on viral neuraminidase (NA) activity. A major component of FGD was isolated and identified as nodakenetin, which is the aglycone of nodakenin. After fermentation, the nodakenetin content in FGD was approximately 10-fold higher than that in GD. Then, we examined the viral NA-inhibitory activity of GD, FGD, nodakenin, and nodakenetin. At a concentration of 500 ㎍/ml, FGD inhibited viral NA activity by 92% compared to the DMSO-treated control, while GD barely inhibited viral NA activity. In addition, 250 ㎍/ml of nodakenetin inhibited viral NA activity by 68% compared to the control, while nodakenin inhibited viral NA activity by only 4% at the same concentration as nodakenetin. Collectively, these results suggest that FGD has a more remarkable viral NA-inhibitory activity than GD because the content of the anti-viral component nodakenetin was higher in FGD due to the hydrolysis of nodakenin by Lactobacillus plantarum KCTC 3104.

• Journal of Environmental Health Sciences
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• v.27 no.4
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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.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.46-52
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• 2007

As flue gas desulfurization (FGD) wastewater contains high concentrations of nitrate and is very low in organic carbon, the feasibility of nitrate removal by autotrophic denitrification using Thiobacillus denitrificans was studied. This autotrophic bacteria oxidizes elemental sulfur to sulfate while reducing nitrate to elemental nitrogen gas, thereby eliminating the need for addition of organic compounds such as methanol. Owing to the unusually high concentrations of dissolved salts $(Ca^{2+},\;Mg^{2+},\;Na^+,\;K^+,\;B^+,\;SO_4^{2-},\;Cl^-,\;F^-,)$ in the FGD wastewater, extensive laboratory-scale and pilot-scale tests were carried out in sulfur-limestone reactors (1) to determine the effect of salinity on autotrophic denitrification, (2) to evaluate the use of limestone for pH control and as source of inorganic carbon for microbial growth, and, (3) to find the optimum environmental and operational conditions for autotrophic denitrification of FGD wastewater. The experimental results demonstrated that (1) autotrophic denitrification is not inhibited up to 1.8 mol total dissolved salt content; (2) inorganic carbon and inorganic phosphorus must be present in sufficiently high concentrations; (3) limestone can supply effective buffering capacity and inorganic carbon; (4) the high calcium concentration may interfere with pH control, phosphorus solubility and limestone dissolution, hence requiring pretreatment of the FGD wastewater; and, 5) under optimum conditions, complete autotrophic denitrification of FGD wastewater was obtained in a sulfur-limestone packed bed reactor with a sulfur:limestone volume ratio of 2:1 for volumetric loading rates up to 400g $NO_{3^-}N/m^3.d$. The interesting interactions between autotrophic denitrification, pH, alkalinity, and the unusually high calcium and boron content of the FGD wastewater are highlighted. The engineering significance of the results is discussed.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.185-191
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• 2017

The objective of this paper is to investigate the effect of waste refractory powder(WRP) and desulfurization gypsum(FGD) as activators on the flow properties and the strength development of high volume blast furnace slag mortar incorporating illite(BSM) having adsorption and deodorization. To fabricate the BSMs with 60% of W/B, blast furnace slag are incorporated with 45% and 65%, respectively. WRP and FGD are substituted from 5 to 10%. Test results indicate that the flow is decreased with increase of WRP and FGD, while increase of WRP and FGD enhance the compressive strength due to accelerated reaction of blast furnace slag, The use of illite results in a decrease of compressive strength. pH has increasing tendency until 7days, while it has reduction. In this paper, optimal dosages of WRP and FGD are believed to be around 5% each.

• Journal of the Korean Ceramic Society
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• v.52 no.6
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• pp.479-482
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• 2015

The flue gas desulfurization (FGD) process is one of the most effective methods to reduce the amount of $SO_2$ gas (up to 90%) generated by the use of fossil fuel. Limestone is usually used as a desulfurizing agent in the wet-type FGD process; however, the limestone reserves of domestic mines have become exhausted. In this study, limestone sludge produced from the steel works process is used as a desulfurizing agent. Seven different types of additives are also used to improve the efficiency of the desulfurization process. As a result, alkaline additive is identified as the least effective additive, while certain types of organic acids show higher efficiency. It is also observed that the amount of FGD gypsum, which is a by-product of the FGD process, increases with the used of some of those additives.

• Journal of the Korean Ceramic Society
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• v.53 no.6
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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.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.475-477
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• 2005

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.205-213
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• 2019

A number of small and medium design companies in Korea are making efforts to develop distinguished products with an aim to survive and prosper. However, it is quite difficult to succeed due to insufficient experience in product planning and the challenges in applying known methodologies, which are based on a large amount of data presented as best practices in designing process, in the actual small and medium enterprise operations. To this end, this study suggested the usefulness of the user participation process as the methodology for small and medium design companies and chose the user FGD method implemented by Company P which is a small design company as an empirical case study. The following are the processes used in the case study; First, the problems of existing baby bath were derived through user FGD. Second, opinions were collected from various classes of users through in-depth interviews. Third, the ideas derived were analyzed with the KJ method and grouped based on similar elements, through which six design directions and detailed design concepts covering size, material, safety, purchase factors of existing product, direction of improvement, additional elements were derived. Through the case study, this study verified that the FGD method of Company P could improve the practical verification, integration and promptness of the product planning process in small and medium enterprises. This is valuable as a realistic process that small and medium enterprises with limited capital and manpower may adopt.