• 자원리싸이클링
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• 제27권1호
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• pp.14-21
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• 2018

희유금속이 포함된 제품의 소비 급증으로 이를 재활용을 통해 자원화하는 것이 매우 중요한 이슈로 떠오르고 있다. 본 연구에서는 폐금속자원 중 코발트와 팔라듐의 폐자원흐름분석을 통해 자원순환 활성화 방안을 각 단계별로 모색하였다. 자원순환 활성화를 위해서 배출/수입단계에서는 대상금속이 포함된 폐기물을 자원으로 분류하는 것이 필요하며, 해당 폐금속자원에 대해 할당관세를 적용할 것을 제안하였다. 수거/폐기단계의 가장 큰 문제는 스크랩 원료 확보의 불안전성으로, 이를 해결하기 위해 현재의 입찰 시스템 개선과 같은 수급안정화 방안의 모색이 필요하다. 전처리 단계에서는 기술 개발 지원, 물질재활용 효율 향상 방안 등의 기술적 부분과 친환경 설계 의무 강화, 클로즈드 리사이클링에 대한 인센티브 부여, 재활용 방법과 기준의 강화 등 제도적 개선이 추진되어야 할 것이다. 자원회수 단계에서는 대기업과 중소기업의 경쟁력 확보를 위해 대 중소기업 상생방안이 마련되어야 할 것이다. 마지막으로 제품생산/수출단계에서는 폐금속자원의 국외 반출량 억제를 위해 코발트와 팔라듐이 포함된 폐자원 수출에 대한 관세를 부과하여야 할 것이다.

• 한국폐기물자원순환학회지
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• 제35권8호
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• pp.721-730
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• 2018

We investigated the effects of heavy metals in cement in the last 3 years and the amount of waste in the cement manufacturing process. The result shows that the average $Cr^{6+}$ content in cement products is controlled at 10 mg/kg. Cu and Pb have lower detection tendency in white cement than in ordinary portland cement. In addition, heavy metals such as Cd show a certain level of detection regardless of the input wastes. Copper slag and phosphate gypsum are the main influencing factors on the heavy metals in cement products. In auxiliary fuels, plastics waste and wood waste are considered to affect heavy metals in cement products. Alternative raw materials are considered to be affected by the alternative raw materials managed as byproducts. In the case of supplementary fuels, auxiliary fuels managed as waste instead of auxiliary fuels managed as byproducts affect the heavy metals in cement. This study examined the input amount without considering the heavy metals in each waste. Therefore, the result may vary in different situations, and further research must be conducted to supplement the findings. However, if the heavy-metal contents in the waste are constant, it can be used as a reference material for the control of heavy metals in cement products.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권4호
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• pp.9-18
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• 2012

This study was carried out to leach valuable metal ions from the mine waste ore using the adapted indigenous bacteria. In order to tolerance the heavy metals, the indigenous bacteria were repeatedly subcultured in the adaptation-medium containing $CuSO_4{\cdot}5H_2O$ for 3 weeks and 6 weeks, respectively. As the adaptation experiment processed, the pH was rapidly decrease in the adaptation-medium of 6 weeks more than the 3 weeks. The result of bioleaching with the adapted bacteria for 42 days, the pH value of leaching-medium in the 3 weeks tend to increased, whereas the pH of the 6 weeks decreased. In decreasing the pH value in the adaptation-medium and in the leaching-medium, it was identified that the indigenous bacteria were adapted $Cu^{2+}$ the ion and the mine waste ores. The contents of Cu, Fe and Zn in the leaching solution were usually higher leached in 6 weeks than 3 weeks due to the adaptation. Considering the bioleaching rates of Cu, Fe and Zn from these leaching solutions, the highest increasing the efficiency metal ion were found to be Fe. Accordingly, it is expected that the more valuable element ions can be leached out from the any mine waste, if the adapted bacteria with heavy metals will apply in future bioleaching experiments.

• 한국광물학회지
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• 제28권3호
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• pp.209-220
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• 2015

폐광산에 방치되어 있는 폐광석으로부터 유용금속이온을 그 지역 토착박테리아를 이용하여 효과적으로 용출시키고자 하였다. 토착호산성박테리아를 중금속 이온에 내성이 형성될 수 있도록 중금속 이온에 주기적으로 반복 적응시켰다. 그 결과 적응실험이 진행될수록 성장-배양액의 pH가 더 안정적으로 감소하였다. $CuSO_4{\cdot}5H_2O$에 9주와 12주 동안 적응시킨 박테리아를 이용하여 42일 동안 미생물용출을 수행한 결과, 용출-배양액의 pH는 적응 횟수에 비례하여 더 빠르게 감소하였다. 황동석과 Cu 함량이 고성 폐광석에 비하여 상대적으로 적게 포함된 연화 폐광석에서 더 많은 박테리아들이 부착하였고, 또한 Cu와 Fe 함량은 고성 박테리아 시료(각각의 용출률 = 66.77%와 21.83%)에 비하여 연화 박테리아 시료(각각의 용출률 = 92.79%와 55.88%)에서 더 많이 용출되었다. 따라서 중금속으로 오염된 광산에 오랫동안 서식한 토착호산성 박테리아를 이용한다면 또한 이 박테리아들을 목적중금속 이온이 포함된 성장-배양액에 계속하여 주기적으로 적응시킨다면, 폐광석으로부터 유용금속이온을 더 효과적으로 용출시킬 수 있을 것으로 확신한다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.253-259
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• 2005

Mine is quickly decline, Nowadays, many of abandoned and closed mines. AMD is abandoned surface water by accumulated yellowboy and caused environmental pollution by amount of heavy metals. The aim of this study waste lime was mixed with the sediment to produce an aggregate far the purpose of neutralizing the acidity and stabilization the heavy metal in the aggregate structure .to pozzolan effect. The result of Waste lime and sediment mixed(5%, 10%, 20%)ration by curing days(3, 7, 38days), After 28 curing days as 5% mixed waste lime leaching solution concentration of all heavy metals is satisfied with regulation limit. Also, the result of fractionate heavy metals to stabilization as 28 curing days very decrease exchangeable and reducible type, and then increase carbonate type. With the above results, waste lime the most effective for the sediment treatment and useful for the recycling waste resource.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.183-187
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• 2001

Present states on reutilization of metal-bearing solid wastes in China including metal-containing gangue, red mud, nonferrous metallurgical slag or residue, arsenical slag, steel - iron slag, waste batteries, were described in detail. The wastes pile up at a large quantity, resulting in seriously potential harm to environment. Most of these wastes, however, contain valuable metals, which are regarded as important secondary resources for extracting metals. Waste slag and batteries with a high grade of metals are treated by a hydro-based and / or pyre-based method for extracting valuable metals. While gangue and waste slag with a low grade are as a raw material in architecture field. In the future, a novel technology, such as high-grads magnetization separation technique and biological technique, will be designed to treat these wastes for protecting environment and recycling valuable components. These wastes, furthermore, are synthetically reutilized to produce various architectural materials, including glass and ceramics.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2019년도 정기학술대회 발표논문집
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• pp.134-134
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• 2019

Utilization of organic waste as a renewable energy source is promising for sustainability and mitigation of climate change. Pyrolysis converts organic waste to gas, oil, and biochar by incomplete biomass combustion. Biochar is widely used as a soil conditioner and adsorbent. Biochar adsorbs/desorbs metals and ions depending on the soil environment and condition to act as a nutrient buffer in soils. Biochar is also regarded as a carbon storage by fixation of organic carbon. Phosphorus (P) and nitrogen (N) are strictly controlled in many wastewater treatment plants because it causes eutrophication in water bodies. P and N is removed by biological and chemical methods in wastewater treatment plants and transferred to sludge for disposal. On the other hand, P is an irreplaceable essential element for all living organisms and its resource (phosphate rock) is estimated about 100 years of economical mining. Therefore, P and N recovery from waste and wastewater is a critical issue for sustainable human society. For the purpose, intensive researches have been carried out to remove and recover P and N from waste and wastewater. Previous studies have shown that biochars can adsorb and desorbed phosphates implying that biochars could be a complementary fertilizer. However, most of the conventional biochar have limited capacity to adsorb phosphates and nitrate. Recent studies have focused on biochar impregnated with metal salts to improve phosphates and nitrate adsorption by synthesizing biochars with novel structures and surface properties. Metal salts and metal oxides have been used for the surface modification of biochars. If P removal is the only concern, P adsorption kinetics and capacity are the only important factors. If both of P and N removal and the application of recovery are concerned, however, P and N desorption characteristics and bioavailability are also critical factors to be considered. Most of the researches on impregnated biochars have focused on P removal efficiency and kinetics. In this study, coffee waste is thermally treated to produce biochar and it was impregnated with Mg/Al to enhance phosphates and nitrate adsorption/desorption and P bioavailability to increase its value as a fertilizer. Kinetics of phosphates and nitrate adsorption/desorption and bioavailability analysis were carried out to estimate its potential as a P and N removal adsorbent in wasewater and a fertilizer in soil.

• 한국식품영양과학회지
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• 제30권2호
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• pp.299-306
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• 2001

As a part of basic investigation for utilization of canned food processing by-products, a food components of the canned oyster processing waste water such as boiled and released water(BRW), wash water(WW) were investigated and compared with hot-water extracts from oyster. From the results of measuring heavy metal conte수, viable cells and coliform group, the canned oyster processing waste waters might not invoke health risk in using food resource. The contents of taste compounds (free amino acids, ATP related compounds, TMA (O) and total creatinine) of BRW and WW accounted for about 254% and 95%, respectively, in comparison with those of control (hot-water extract from oyster). The BRW showed a very high content of salt in comparing to the WW and control. In descending order, the values of whiteness index was WW, control and BRW. Sensory scores for color, oyster flavor intensity and saline taste were not significantly different between WW and control. But, BRW had the highest score in oyster flavor intensity, while had the lowest score in color and saline taste. But, the color and saline taste of BRW might be able to control by some pretreatment (concentration and drying in mild condition, desalination and recipe control etc). These results indicated that BRW and WW generated from various step during canned oyster processing could be a potential food resource by controlling of saline taste and color intensity.

• 대한환경공학회지
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• 제31권6호
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• pp.449-453
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• 2009

본 연구에서는 사업장에서 발생되는 지정폐기물 중 폐기물관리법상 규제되고 있는 유해물질류 7종의 함량 특성을 조사하였다. Cu, Pb 등과 같이 규제되고 있는 중금속의 배출 가능성이 높은 표본사업장을 선정하여 9개 업종, 90개 사업장에서 슬러지, 폐촉매 등 폐기물 종류별 시료 108건을 채취 분석하였다. 분석방법은 선진국의 분석방법을 토대로 제안한 함량시험방법으로 분석하였고 그 결과는 함량기준으로 관리하고 있는 오스트리아의 규제기준과 비교검토하였다. 그 결과 Cu는 모든 업종에서 비교적 높은 농도로 검출되었으며, 특히 코크스.석유정제품 제조업, 1차 금속산업, 전자부품, 영상, 음향 및 통신장비제조업에서 발생된 오니, 분진, 소각재 등의 폐기물이 오스트리아 기준 100 mg/kg 보다 높은 농도로 나타났다. Pb은 1차 금속산업에서 발생된 분진에서 높은 농도로 검출되었으며 총 크롬의 경우에는 상업분류코드 18, 19, 23 등에서 높은 농도로 나타났다. 또한 Cr(VI)을 분석한 결과, 봉제의복 및 모피 산업에서 발생된 분진에서 높은 농도를 나타나는 것으로 조사되었다.

• 상하수도학회지
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• 제33권4호
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• pp.291-297
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• 2019

Phosphorus is a vital resource for sustaining agriculture and nutrition, but a limited non-renewable resource. Thus, the recovery of phosphorus from waste activated sludge(WAS) was attempted by microwave heating and magnesium ammonium phosphorus(MAP) crystallization. Polyphosphate-accumulating organisms(PAOs) in WAS release phosphate from the cell when they are exposed to high temperature environments. Microwave heating caused phosphorus and ammonia to release from WAS. The amount was increased with increasing temperature, showing that 88.5% of polyphosphate present in the cells were released in the form of phosphate at $80^{\circ}C$. A similar result was also observed in the release of ammonia. On the other hand, both phosphorus and ammonia were crystallized with magnesium, and then was harvested as MAP. Phosphorus recovery rate reached almost 97.8%, but the ammonia was about 13.4%. These results cleary indicate that phosphorus could be recovered from WAS using a physiological trait of PAOs. Heavy metal analyses also show that the MAP crystal is useful and safe as a phosphorus fertilizer.