• Journal of Soil and Groundwater Environment
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• v.12 no.4
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• pp.78-85
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• 2007

This study provides an attempt to evaluate sanding wastes, generated from a chemical company as a reused adsorbent. Organic impurities in the raw sanding wastes were removed by calcination at $550^{\circ}C$. Aluminum was a major inorganic composition in the raw sanding wastes and increased from 29.09% to 52.73% after calcination. Dissolved concentrations of heavy metals from the calcined sample were below 0.3 mg/L in a stability test at pH 2. From the pH-edge adsorption experiments with the calcined sanding wastes, As (V) was found to follow an anionic-type adsorption. Adsorption isotherm obtained with variation of the dosage of the calcined sanding wastes was better described by Freundlich equation than Langmuir one. Freundlich constants of K and 1/n were 4.244 and 0.316, respectively. The As (V) adsorption capacity of calcined sanding wastes estimated from Langmuir isotherm was 13.25 mg/g. From this study, the calcined sample was identified as a good reusable adsorbent in the view point of stability and adsorption capacity on As (V).

• Clean Technology
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• v.21 no.3
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• pp.141-152
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• 2015

As environmental issues are emerging, bio-plastic suppliers in leading countries have been foreseeing the strong needs for environment-friendly materials such as eco-packing materials due to increased attention and regulation on recycle. To catch up with the demand, various types of bio-plastics based on natural feedstocks were developed and released on a market. These bio-plastic products drew the great attention even in domestic industries. At present, international oil price fluctuation and heavy charge on waste raise the unit cost of production and disposal expense of conventional plastic materials. These conditions make bio-plastic an alternative, because it is not restrained by oil prices and problem in the disposal. It is also expected that bio-plastic will be applied to various types of products including containers, industrial supplies, disposables, and medical supplies. However, the bio-plastic is still in its infancy, thus more research and understanding should be followed to put it to application. Bio-plastic is considered as environment-friendly material with high potential which has the advantages of production and disposal.

• Journal of the Korea Concrete Institute
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• v.19 no.6
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• pp.667-676
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• 2007

As the 21st century began, cement and concrete that are representatives of modem building materials became a major factor in global warming, air pollution and environmental pollution. Also, the problems that are generated while pursuing high performance and high strength became social issues. Therefore, it has become urgent to prepare counter plans. This study has aimed at the recycling of sewage sludge ash and developing it as a new concept in building material which serves the environmental considerations for long-lasting developmental purpose. Also, the study aimed to find a substitute for scarce natural resources and to secure high techniques for waste recycling. The purpose of this study was also to solve fundamentally secondary environmental pollution. The results revealed that the chemical components of sewage sludge ash are mainly $SiO_2\;and\;Al_2O_3$ which are similar to the components of pozzolan. Also, it was identified that sewage sludge ash can be utilized as a hardened specimen with an alkali activated pozzolan reaction. Considering the possibility of appropriate strength development and the advantage of drying shrinkage, compared with that of cement, it was believed that sewage sludge ash can demonstrate a function as a substitute for cement given.

• Journal of Soil and Groundwater Environment
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• v.10 no.6
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• pp.68-74
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• 2005

This study was carried out to evaluate the feasibility of field-scale sequential soil washing process for remediation on Kyongsangnamdo D mine soils which was heavily contaminated by arsonic. Arsenic concentration of untreated soils was $321\pm32mg/kg$. By applying the basic operating condition which was proposed from several pilot-scale experiments, arsenic concentration of treated soils was reduced 2.04 mg/kg ($99\%$ removal efficiency). We optimized the basic operating condition (mainly on washing solution concentration, cut-off size, and mixing ratio) to improve efficiently and economically the field-scale sequential soil washing process. The resulting optimized conditions were that solution concentration is 0.2M HCl, 1.0M HCl, 1.0M NaOH, that the cut-off size is 0.15mm (seive $\sharp$100), and that the mixing ratio is 1 3. Also, the optimized pH value for soil washing effluent treatment was 6 (33 ppb), in which the precipitation disruption caused by supersaturation of the floe did not occur. Results of TCLP tests showed that arsenic concentration from the washed gravels was 1.043 mg/L, that from soils ND (not detected), and that from filter cakes 0.066 mg/L. Also, the water content as a percentage of dewatered sludges was low $(48\%)$ and so the dewatered sludges can be disposed by landfilling. Through these results, we can concluded that tile field-scale sequential soil washing process developed in this study is adopted for remediation of arsenic-contaminated soils.

• Journal of the Korean GEO-environmental Society
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• v.17 no.10
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• pp.45-53
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• 2016

At present, coffee consumption amount is annually on the rise in Korea, which results in about 0.27 million tons of coffee waste annually. They are mostly classified as food waste and deserted with moisture contained, being a serious environmental issue. Existing slope greening techniques, which are vegetation based soil-media hydroseeding measures, have problems such as lack of coherence, dryness or lack of organic matters. Therefore in order to assess usability of Spent Coffee Ground (SCG), medium-to long-term growth test was conducted under the indoor and outdoor conditions. According to the result of growth test, when SCG was mixed with existing base materials, moisturizing power increased and organic matter content was reinforced, promoting germination and growth in a medium term. Among others, under the condition when supply of water was discontinued, withering rate was lower than existing base materials and diverse phenomena resulting from lack of nutrition decreased. Therefore, SCG as a waste organic matter with abundant nitrogen has the characteristic of inhibiting early growth but was found to have a quality favorable to long-term growth resulting from water containing ability and the supply of organic mater and is judged to be a material to replace or complement existing base materials.

• Journal of the Korean earth science society
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• v.24 no.7
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• pp.635-649
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• 2003

Heavy metal concentrations and benthic foraminiferal distributions were investigated in three short sediment cores in order to understand the pollution history in Masan Bay. Sedimentation rates were 0.33 cm/yr, 0.20 cm/yr and 0.33 cm/yr in the inner bay, the out fall of Dugdong sewage disposal plant, and bay mouth, respectively. The rapid increases of copper, zinc and lead concentrations at the core depth of 10 cm the upper part indicated that Masan Bay has been polluted with industrial wastes since the 1940s. Benthic foraminifera in core sediments show that the variations in their distribution were followed by industrial pollution in the bay. The number of individuals and species diversity decreased, whereas agglutinated tests increased upward in the cores with increased heavy metal pollution. These shifts effectd the abundance of few tolerant forms and consequently decreased the species diversity. The opportunistic species Eggerella advena and Trochammina pacifica increased in polluted sediments. These species can be used as an indicator for assessments of environmental quality in Masan Bay.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.177-189
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• 2003

The main purposes of this study are to utilize mineralogical studies such as optical microscope, XRD and SEM/EDS analyses to characterize the oxidation of sulfide minerals and the mechanisms controlling the movement of dissolved metals from waste rocks at the abandoned Seobo mine. Mineralogical research of the waste rocks confirms the presence of anglesite, covellite, goethite, native sulfur and nsutite as secondary minerals, suggesting that these phases control the dissolved concentrations of As, Cu, Fe, Mn, Pb and Zn. The dissolved metals are precipitated, adsorbed and/or coprecipitated with(or within) Fe(Mn)-hydroxides and Mn(Fe)-hydroxides. The main phases of secondary mineral, Fe-hydroxide, can be classified as amorphous or poorly crystalline and more crystallized phases(e.g. goethite) by crystallinity. Amorphous or poorly crystalline Fe-hydroxide has relatively high As contents(9-24 wt.%). This poorly crystalline Fe-hydroxide changes toward more crystallized phase(e.g. goethite) which contains relatively low As(0.6-7.7 wt.%). These results are mainly due to the progressive release of As with the crystallization evolution of the As-trapping poorly crystalline Fe-hydroxides. It is also attributed to the differences of specific surface areas between the poorly crystalline Fe-hydroxides and well crystallized phases. The dissolved metals from waste rocks at Seobo mine area are naturally attenuated by a series of precipitation(as Fe, Mn, Cu, Pb), coprecipitation(Fe, Mn) and adsorption(As, Cu, Pb, An) reactions. The results of mineralogical researches permit to assess the environmental impacts of mine waste rocks in the areas, and can be used as a useful data to lay available mine restoration plan.

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.48-53
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• 2004

This study is objected to estimate the variation of the coefficient of leachate according to designs in landfill cover systems. Design (a) is the unsanitary landfill cover system with 50 cm soil. But Design (b), (c) are sanitary cover systems which are composed of soil top layer, drainage layer, barrier liner(Design (b): Geomembrane(1.5 mm) and compacted clay liner(30 cm), Design (c) compacted clay liner(45 cm)), gas venting layer. Quantity of leachate estimates Rational Method generally and depend on the coefficient of leachate, on one of the factors in Rational Method largely. The coefficient of leachate is defined as the leachate production ratio result from incident precipitation. To estimate the variation of the coefficient of leachate, the authors use HELP(Hydrologic Evaluation of Landfill Performance) Simulation and Pilot Test. As a result of HELP Simulation, the coefficient of leachate is 0.36∼0.42 in Design (a) and 0.03∼0.15 in Design (b), (c) according to designs in landfill cover systems and quality of barrier liner placement. These numerical values are similar to 0.13 with the coefficient of leachate in Pilot Test.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.55-64
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• 2007

An analytical method using ion-exchange chromatography was developed for simultaneous quantification of low-molecularweight organic acids ($C_1-C_6$ aliphatic carboxylic acids) and inorganic anions, and then applied to the assessment of ground water contaminated by leachates from a municipal solid waste landfill. Peak interferences of halide ions to organic acids were removed by pretreatment of water samples with Ag-containing cartridges. This method allowed accurate detection of low-molecular weight organic acids (i.e., formate, acetate, propionate, pyruvate, succinate, and oxalateas) low as 0.5 mg/L with a linear dynamic range up to 20 mg/L within 11 min run time along with typical inorganic anions. High level of pyruvate and low level of formate and acetate were detected in groundwater and landfill leachates using the analytical method. Pyruvate concentration in groundwater showed a significant correlation with concentrations of $Cl^-$ and $HCO_3^-$, and pyruvate levels decreased along the downgradient from the landfill, indicating the sources of pyruvate are landfill leachate.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.2
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• pp.121-128
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• 2006

In this study, the existing MSS facilities were investigated for examination the the present condition of MSS treatment system. There are 23 MSS treatment facilities across the country, In total facilities, 6 facilities have economical problems, and 2 facilities were stopped the operation of establishments for technical problems, and most facilities are suffering from environmental problems, for example, odor and waste water. These kinds of problems play a role as obstacle to treat MSS efficiently. Accordingly, to reform current MSS treatment system, a few adequate measures are required. First a Guide line, which is a manual for establishment of MSS treatment facilities efficiently and environmentally friendly, must be offered from the agencies concerned of the Ministry of Environment to local governments. Second, to devise a plan for MSS treatment, Ministry of Environment and all local governments should devise a long-range policy synthetically not fragmentarily and temporarily.