• Geomechanics and Engineering
• /
• 제19권5호
• /
• pp.383-392
• /
• 2019

How to safely and economically dispose mining tailings is a challenge to mine operators. This paper presents an alternative upstream method for tailings dam construction, termed as the template construction method (TCM), which has been successfully implemented at Zhelamuqing tailings impoundment since 2004. By the beginning of 2015, the tailings dam wall had reached 95 m in height for the 46 upstream raises, with the total height of the dam including the starter dyke being 128 m. The proposed TCM is relatively simple and cost-effective and provides a good way for constructing rapidly raising tailings dam based on this case.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2003년도 추계학술발표회
• /
• pp.422-425
• /
• 2003

This study was carried out to apprehend the variation of quality of mine drainage in the abandoned Samtan coal mine. After closure of coal mine, although still pumping, water level in underground was raised to loom and the concentration of some elements such as Fe and Mn was elevated. At present, the worst pollution source in this area is too the acidic leachate drained from uncovered mine waste impoundment. The flow rate of mine drainage from the adit is ave. about 20,000t/d. If water were flooded and deteriorated due to stopping pumping, the impact of the mine drainage on the stream around the abandoned mine would be more severe. Therefore, It is considered that the prediction of water quality of mine drainage from the adit after stopping pumping will be very important with a view to establishing countermeasures.

• 한국세라믹학회지
• /
• 제33권2호
• /
• pp.135-142
• /
• 1996

Fly Ashes which are produced from coal-fired powder plants and classified as general waste can be used as raw materials for bricks and tiles because of their compositional similarity with clays. There was a limit of substituting fly ash for clay because plasticity decreased with increasing fly ash additions. Accordingly this study tried to suggest a feastibility of enhancing the substitution ratio by controlling the interfacial properties of fly ash. The slip with 1:1 volume ratio showed that best dispersive characteristics under the condition of pH 2 Filter pressed cakes made of pH 2 slips also showed better plastickity than those of untreated ones. of pH 2 Filter pressed cakes made of pH 2 also shwoed better plasticity than those of untreated ones.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 1996년도 사용종료 매립지의 안정화 에 관한 국제 세미나
• /
• pp.97-101
• /
• 1996

Municipal and sanitary landfills can pose environmental problems due to leachate, landfill gas md unstable geotechnical properties. Most governmental bodies delay the correction of landfill problems or landfill replacement until a crises stage is reached. The replacement of a landfill is often made difficult due to costly regulatory controls, public opposition to siting and the high cost of closure for the previous landfill unit. Solutions to extending landfill life and capacity Involve waste minimization by recycling, refuse compaction and waste-to-energy incineration. Incineration can reduce the volume of refuse by 50-95%. The largest installed bases of municipal waste Incinerators are located in Japan and the U.S. The volume of waste contained in a landfill can be estimated by load count tabulations, weight-and-volume measurements or a material balance analysis based on the trash profile of user categories. for an existing landfill, core samples may be collected and analyzed for use in a material balance analysis. Newly generated refuse contains approximately 50% of the heating value of coal. However, landfill properties vary significantly due to the waste profile of the contributors and biodegradation due to time and weathering. The volume of the Nanji-do landfill

• Korean Chemical Engineering Research
• /
• 제54권4호
• /
• pp.501-509
• /
• 2016

황함유량이 높아 독성 폐기물로서 분류되는 석유코크스를 역청탄 및 아역청탄과 혼합하여 가스화 공정을 통해 액체연료를 생산하는 공정의 경제성을 분석하였다. 공정의 경제성을 분석하기 위한 2,000 톤/일 규모의 액화 공정은 가스화, 정제, Fischer-Tropsch 전환 등으로 이루어진다. 기발표된 자료들로부터 적절한 검토 기준을 통해 건설비용 및 매출액을 산정하였고 석유코크스/석탄의 혼합비에 따른 경제성을 평가하였다. 경제성 평가 결과, 원소황의 생산과 판매 증가로 인해서 석유코크스의 경제성이 석탄보다 우수했으며 수분 함량이 낮은 역청탄과의 혼합이 보다 높은 경제성을 가지는 것으로 나타났다. 아역청탄의 경우, IRR (Internal rate of return)이 10% 이상이 되기 위해서는 석유코크스와의 혼합이 적어도 40 wt% 이상이 되어야 함을 확인하였다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
• /
• pp.1051-1060
• /
• 2008

The use of the coal ash for surcharge material, in a view of the environmental aspect, can decrease amount of the reclamation through recycling waste materials as well as prevent a destruction of the ecosystem attributed to sand picking. In addition, it can reduce both unit cost of material and construction expenses. In this study, new construction material as alternative surcharge material using coal ash, which is by-product from thermoelectric power plant, were developed. Mixing ratios of fly ash and bottom ash derived from the coal ash in Samchunpo thermoelectric power plants were determined. Furthermore, mixing conditions depending on the ratios of the cement and gypsum used for chemical additive were determined too. Uniaxial compression strength tests were conducted at different mixing conditions and Design graph of optimum mixing ratio at each required strength for economic efficiency is indicated in this paper.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제18권4호
• /
• pp.40-49
• /
• 2013

In the beginning of $20^{th}$ century, the coal mining industry had an important role in Japan at which two-thirds of the coal product came from the Kitakyushu-Chikuho District (KCD). As a consequence of mining activities, land-use condition in this district showed notable changes. This paper presented a study of land-use changes in coal mining area by characterizing land-use pattern transition over the last 100 years. In order to carry out the rigorous analysis of land-use, a series of land-use maps over the last 100 years was developed using geographic information systems (GIS). The historic topographic map and another available old data were used to investigate the long-term changes of land-use associated with past mining within the GIS platform. The results showed that the utilization of a series of developed land-use maps successfully indicated the difference of land-use pattern in the KCD before and after the peak of mining activities. The general findings from land-use analysis described that forest and farm lands were lost and turned into abandoned sites in the last 100 years.

• 한국환경과학회지
• /
• 제23권12호
• /
• pp.1987-1998
• /
• 2014

Zeolite was synthesized from power station waste, coal fly ash, as an alternative low-cost adsorbent and investigated for the removal of Sr(II) and Cs(I) ions from single- and binary metal aqueous solutions. In order to investigate the adsorption characteristics, the effects of various operating parameters such as initial concentration of metal ions, contact time, and pH of the solutions were studied in a batch adsorption technique. The Langmuir model better fitted the adsorption isotherm data than the Freundlich model. The pseudo second-order model was found more applicable to describe the kinetics of system. The adsorption capacities of Sr(II) and Cs(I) ions obtained from the Langmuir model were 1.7848 mmol/g and 0.7640 mmol/g, respectively. Although the adsorption capacities of individual Sr(II) and Cs(I) ions was less in the binary-system, the sum of the total adsorption capacity (2.3572 mmol/g) of both ions in the binary-system was higher than the adsorption capacity of individual ion in the single-system. Comparing the homogeneous film diffusion model with the homogeneous particle diffusion model, the adsorption was mainly controlled by the particle diffusion process.

• 청정기술
• /
• 제29권1호
• /
• pp.22-30
• /
• 2023

몽골은 전 세계에서 대기오염문제가 매우 심각한 나라 중 하나이다. 그 원인으로는 몽골 울란바타르시 내 게르촌에서 사용되는 저급연료의 난방연소 때문이다. 본 연구에서는, 몽골 울란바타르시 게르촌에서 사용되고 있는 저급연료 및 몽골 폐식용유의 연료품질을 분석하였으며, 전통난로와 시작품 연소난방장치의 연소테스트를 통해 환경성을 평가하였다. 또한 인체위험도 분석을 통해 난방장치의 대체효과를 평가하였다. 연료특성분석 결과, 몽골석탄 중 조개탄은 회분, N, S 함량이 높은 이유로 환경성이 상대적으로 안좋은 것으로 분석되었다. 또한 3종의 석탄에 비해 폐식용유를 연소하였을 때, 대기질 개선효과가 높은것으로 나타났다. 몽골 전통난로를 시작품난로(폐식용유 사용)로 교체할 경우, 몽골 울란바타르시의 대기환경문제를 개선할 수 있는 효과가 있을 것으로 판단된다.

• 에너지공학
• /
• 제26권4호
• /
• pp.35-44
• /
• 2017

Disposal of municipal solid waste has become a major problem in many countries around the world. As landfill space for the disposal of ash from Municipal Solid Waste Incineration (MSWI) becomes scarce, numerous reports and researches address the various environmental issues about the municipal solid waste incineration waste management and other particulate matters with the range of 10 ~ 2.5. Although in many developing and industrialization countries landfill with the disposal of municipal solid waste, open incineration has become a common practice. Large municipal waste incinerators are major industrial facilities and have the potential to be significant sources of environmental pollution. Despite the significant volume reduction from incineration, waste recycling is important to ensuring the future welfare of mankind. The main goal of the present work is the physical and chemical characterization of the local incineration bottom ash towards its eventual re-utilization. In this paper, we reported the studies on physical and chemical characteristics of municipal solid waste incineration (MSWI) fly ash and bottom ash containing particulate matter whose particulate sizes are lower than $PM_{10}$, $PM_{2.5}$ and heavy metal were investigated.