• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.3
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• pp.133-137
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• 2007

Ecological lightweight aggregates were made in order to recycle the dredged soils from the seaside construction area and the bottom ashes from the power plant. Various physical and chemical analysis were performed on them to identify their possibility for applying lightweight concrete fields. Lightweight aggregates were made of bottom ashes and dredged soils from Yongheung Island which is located 20km west away from Seoul, and all the raw materials were milled before mixing. The physical and chemical properties such as density, absorption rate, stability, alkali latency reaction, heavy metal leaching of the lightweight aggregates were tested and analysed by following the KS standard procedures. From the size analysis, the coarse aggregates showed a suitable fit on standard particle ranges; however, the fine aggregates showed a large deviation from the standard. The absorption rates were increased with decreasing weight of the aggregates. All the aggregates were turned out to be safe by the stability and heavy metal leaching test; however, some of the aggregates were confirmed on the border of harmless and possibly harmful region through the alkali latency reactivity test.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.113-122
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• 2007

Experimental studies were performed to investigate speciation and leaching potential of heavy metals(Cu, Cd, Pb Zn, Ni) in ten sediment samples collected from Nakdong River. Acid Volatile Sulfide (AVS) and Simultaneously Extractable Metals (SEM) measurements were used to estimate heavy metals that can be leached under anaerobic conditions. Sequential Extraction Procedure (SEP) and Toxicity Characteristic Leaching Procedure (TCLP) were used to characterize speciation and leaching potential of heavy metals under aerobic conditions. The results show that total concentrations of Cu, Zn and Ni were relatively high in the sediments from points Seongseo industrial complex stream (upper stream) (D), Seongseo industrial complex stream (midstream) (E), Dalseo stream (F), and Nakdong river estuary (J), and that Cd concentrations were higher in all sampling points except for Goriung Bridge (G) and Soosan Bridge (H). SEM and AVS analyses reveal that samples from points Ilsun Bridge (A), Namgumi Bridge (C), and Soosan Bridge (H) have potential of heavy metals leaching, although leachable concentrations are relatively low. The leaching potential of heavy metals in other points was low because of higher concentrations of AVS than SEM. SEP results show that more than 50% of Cu, Zn and Ni were present in residual fraction, which means these metals are less amenable to leaching in anaerobic conditions. On the other hand, more than 50% of Pb and Cd were extracted during the first through third step of the SEP, which means substantial fraction of these metals can be leached upon changing of redox conditions. TCLP tests predict that leaching potential of heavy metals was generally low, which is consistent with the results obtained by AVS and SEM measurements.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.153-153
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• 2023

골프장 건축 시 하부지반 구축을 위해 사용하는 잔석의 산화로 인해 중금속 용출이 발생할 수 있다. 용출된 중금속으로 인근 농업지역이 오염될 경우 인간의 식생활에 직접적인 영향을 미쳐 인체건강에 악영향을 끼칠 수 있다. 특히, 망간의 경우 식품을 통해 과다섭취할 경우 정신착란, 운동실조 등 다양한 신경학적 문제를 발생시키기 때문에 망간 오염에 대한 조사 및 관리는 필수적이다. 따라서, 본 연구는 최근 골프장이 건설된 부산시 일광 회룡리 일대 농업지역에서 망간 오염 평가를 위해 지표수, 퇴적물, 벼 작물을 채취하여 망간 농도 분석을 수행하였다. 골프장 유출조부터 시작되는 관개수로에서 지표수와 퇴적물 시료를 약 20 m 간격으로 채취하였으며, 관개수로의 구조에 따라 논을 4개의 구역(Area 1 - 4)으로 구분하여 논 토양과 벼 작물을 채취하였다. 벼 작물의 경우 뿌리, 줄기, 곡물 부분으로 나누어 채취하였으며, 퇴적물과 논 토양은 시료 내 존재하는 망간의 형태를 확인하기 위해 연속추출법을 통해 분석하였다. 분석 결과 지표수의 망간 농도는 골프장 유출조에서 하류로 갈수록 감소하는 경향을 보였으며, 하류에서의 망간농도는 상류에 비해 최대 88% 감소하였다. 퇴적물의 망간 농도는 논으로 연결되는 지점에서 20,000 mg/kg 이상의 높은 농도를 보였으며, 농업이 진행 중인 3, 5, 7월은 최대 약 25,000 mg/kg의 농도를 보였으나, 농업이 끝난 9월에는 최대 약 3,500 mg/kg으로 상대적으로 낮은 농도를 보였다. 논 토양의 망간 농도는 관개수로와 첫 번째로 연결되는 Area 1에서 1,600 mg/kg으로 측정되었으며, 이는 EPA에서 권고한 논 토양 망간 기준 1,000 mg/kg을 초과하는 농도로 확인되었다. 또한, 식물이 사용할 수 없는Residual 형태의 망간 농도는 변화가 없었으나, 식물이 사용 가능한 Acid soluble, Reducible, Oxidizable 형태의 망간 농도는 추수기 이후 80% 이상 감소하였다. 벼 작물의 곡물 망간 농도는100 - 200 mg/kg으로 USDA에서 발표한 쌀 곡물 망간 농도의 평균인 5 mg/kg보다 약 20배 이상 높게 검출되었다. 본 연구 결과를 통해 골프장 유출조로부터 발생하는 망간오염을 식별하고 주변 농업지역에 미치는 영향을 확인할 수 있었으며, 추후 골프장 운영으로 인한 환경오염에 대한 관리가 필요할 것으로 생각된다.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.575-585
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• 2007

Microbial control of the geochemical behavior of heavy metals (Cd, Cu, Pb, and Zn) and As in contaminated subsurface soil and sediment was investigated through activation of indigenous bacteria with lactate under anaerobic condition for 25 days. The results indicated that dissolved Cd, Pb and Zn were microbially removed from solutions, which was likely due to the formation of metal sulfides after reduction of sulfate by indigenous sulfate-reducing bacteria. Soils from the Dukeum mine containing a large amount of sulfate resulted in complete removal of dissolved As after 25 days by microbial activities, while there were gradual increases in dissolved As concentration in soils from the Hwabuk mine and sediments from the Dongducheon industrial area which showed low $SO_4{^2-}$ concentrations. Addition of appropriate carbon sources and sulfate to contaminated geological media may lead to activation of indigenous bacteria and thus in situ stabilization of the heavy metals; however, potential of As release into solution after the amendment should be preferentially investigated.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.32-38
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• 2011

In this study, the correlations of concentrations in sediment heavy metals between two pretreatment methods, total digestion and aqua regia digestion, have been investigated. Total 43 samples had been collected from streams and lakes in Yeongsan and Seomjin watersheds. They were decomposed in two pretreatment methods and five metal components (Cd, Cr, Ni, Pb, Zn) were analyzed. Overall average concentrations of heavy metals were Zn>Cr>Pb>Ni>Cd in the order. The concentrations of aqua regia digestion were 35.0% (Cd), 53.8% (Cr), 66.2% (Ni), 64.4% (Pb) and 76.4% (Zn) of the concentrations of total digestion and heavy metal concentrations of total digestion were higher. Heavy metal concentrations in sediments from lakes were higher than those from streams. The correlation equations between the concentrations of total digestion and aqua regia digestion were obtained. The concentrations of Zn and Ni, which showed strong linear correlations, increased in aqua regia digestion as the concentration in total digestion increased. The linear correlation coefficients between two digestion methods for most analyzed metals were above the average correlation. However, these results can be applied with limitations due to heterogeneity of sediments.

• Journal of the Korea Convergence Society
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• v.8 no.2
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• pp.157-162
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• 2017

Inorganic stiffening agents were prepared by mixing paper sludge incineration ash, blast furnace slag fine powder quicklime, anhydrous gypsum and fly ash. The main components of the solidifying agent developed for sludge treatment were SiO, $Al_2O_3$, $TiO_2$, $Fe_2O_3$, $Mn_2O_3$, CaO, MgO, $Na_2O$, $K_2O$, $P_2O$, and $SO_3$. Unlike cement, the developed solidifying agent did not contain $Cr^{6+}$, which is known as a carcinogen. Heavy metals and oil contaminated soil were mixed with solidifying agent and cured for 7 days and the heavy metal content was below the environmental standard. Sewage sludge cake, food waste and solidifying agent were mixed with each other, and after 7 days curing, soil component test showed that the heavy metal content was below the environmental standard. After mixing the sludge, solidifying agent and additive mixture into the beaker, the ammonia concentration was measured to be 0 after 3 days.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.82-91
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• 2004

In order to utilize inorganic components in coal and wastewater sludge as an environmentally stable material, slag-forming is considered as one of the suitable methods better than producing as an ash. Coal slag that was produced by gasification as well as the slag made from wastewater sludge by incineration or melting process have been analyzed with the viewpoint of recyclability. Slags produced by water quenching exhibited a cracked shape that has a size of few millimeters with sharp edges. Slags contain the unburned carbon content below 0.15％ and expose mostly amorphous structural characteristics. Analysis results in the extraction of heavy metal compounds demonstrate that both slags from coal and wastewater sludge could be utilized as a safe recycle material even with a Japanese environmental regulation that is ten times more stringent than the current Korean standard. Slags from coal and wastewater sludge show significant differences in contents of each heavy metal compound. Since the future trend of environmental regulation shifts to the control of total content for each heavy metal compound, proper mixing of slags that contain different heavy metal contents might be an option for manufacturing recycle materials.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.10
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• pp.574-579
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• 2016

This study assessed feasibility of making granular fertilizer with fly ash from a sewage sludge incinerator in Korea. Composition, characteristics, strength, and heavy metal contents of the granular fertilizers were investigated. Due to its high contents of phosphorus, fly ash from a sewage sludge incinerator could be used to make fertilizers. Granulation rates (2-4 mm granules) over 80% could be achieved as the fly ash contents were 15% or less of the fertilizer. Leaching tests of the fertilizers, based upon the Korean Standard Methods for Solid Wastes, showed the concentrations of heavy metals less than the risk limits. However, contents analysis of the fertilizers, based upon the Korean Standard Methods for Soils, experienced higher levels of heavy metals than the risk limits as the fly ash content exceeded 7% of the fertilizer. Thus, the fly ash needs to be added less than 7% of the fertilizer if there is no pretreatment to remove heavy metals.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.352-355
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• 2012

산성광산배수(Acid Mine Drainage)는 낮은 pH, 높은 Sulfate, 상대적으로 높은 Fe, Al, Mn 등의 중금속 농도가 특징으로 다양한 오염인자를 가지고 있으며, 각각의 오염인자가 오염에 미치는 영향이 매우 다양하게 나타난다. 특히 산성광산배수는 유역 내 시각적, 생태학적 문제를 일으켜 많은 환경오염을 야기하고 있으며, 많은 중금속을 용출시켜 주변 하천의 생태계를 파괴하게 된다. 이러한 산성광산 배수에 의한 환경피해의 심각성은 이미 국 내외에서 널리 인식되고 있으며, 이를 효과적으로 관리하기 위해서 산성광산배수의 거동 매커니즘 조사에 대한 연구가 필요하다. 따라서 본 연구에서는 금강수계 거풍광산 유역 장연천을 대상으로 하여 광산주변 표토, 계절별 거리별 하천수 및 저질토에서의 오염특성을 조사하고 그 영향을 평가하고자 하였다. 연구결과 하천수의 경우 대부분의 중금속 농도가 오염물질의 축적이 가장 많을 것으로 예상되는 5월에 높은 농도를 보였으며, 강우가 시작되는 6월, 7월까지 건기에 비해 높은 농도를 유지하다가, 강우가 지속됨에 따라 희석되어 농도가 감소되는 현상을 나타냈다. 저질토의 경우도 비슷한 양상을 타나냈다. 거리별 영향의 경우 하천수는 산성광산배수가 유입되는 상류에서 지속적으로 높은 농도를 나타냈으나, 저질토의 경우 건기에는 비슷한 양상을 나타내다가 우기에 강우의 영향으로 하천 하류에서 전체적으로 농도가 높아지는 경향을 나타냈다.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.11
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• pp.751-756
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• 2012

In this study, a heavy-metal stabilization treatment using stabilizing agents derived from waste resources was utilized on Incheon North Port range sediment contaminated with Pb, Zn, and Cu. Both calcined red mud (5%, 10%, and 15% w/w) and oyster shell (5%, 10%, and 15% w/w) were applied for a wet-curing duration of 15 days. From the sequential extraction results, the oxide and organic fraction of heavy metals (Pb, Zn, and Cu) were observed strongly in the contaminated sediment. However, the fraction of heavy metal in the stabilized sediment was higher than the organic and residual fraction, in comparison to the contaminated sediment. Moreover, the leaching of heavy metals was reduced in the stabilized sediment, compared with the contaminated sediment. From these results, red mud and oyster shell were shown to be potential stabilizers of heavy metals in contaminated sediment.