• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.37-44
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• 2003

Fuel oxygenates, such as Methyl tertiary Butyl Ether (MTBE) is additive in gasoline used to reduce air pollution. Gasoline components and fuel additives can leak: form underground storage tanks. MTBE is far more water soluble than gasoline hydrocarbons like BTEX then it travels at essentially the same velocity as groundwater. MTBE in drinking water causes taste and odor problems. Therefore, the purpose of the this study is to examine the ability of ground tire to sorb MTBE in water. The study consisted of running both batch and column tests to determine the sorption capacity, the required sorption equilibration time, and the flow through utilization efficiency of ground tire. The batch test result indicated that ground tire can attain equilibrium sorption capacities about 0.5 mg of MTBE. The result of column test indicate that ground tire has on the 36% utilization rate. Finally, it is clear that ground tire represented an attractive and relatively inexpensive sorption medium for a MTBE. Authors thought that to determine the economic costs of ground tire utilization, the cost to sorb a given mass of contaminant by ground tire will have to be compared to currently accepted sorption media. The cost comparison will also have to include regeneration and disposal cost.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.231-238
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• 2008

This study proposed the method of phosphate recovery from municipal wastewater by using ferrous iron waste, generated from the mechanical process in the steel industry. In the analysis of XRD, ferrous iron waste was composed of $Fe_3O_4$ (magnetite), practically with $Fe^{2+}$ and $Fe^{3+}$. It had inverse spinel structure. In order to identify the adsorption characteristic of phosphate on ferrous iron waste, isotherm adsorption test was designed. Experimental results were well analyzed by Freundlich and Langmuir isotherm theories. Empirical constants of all isotherms applied increased with alkalinity in the samples, ranging from 1.2 to 235 $CaCO_3/L$. In the regeneration test, empirical constants of Langmuir isotherm, i.e., $q_{max}$ (maximum adsorption capacity) and b (energy of adsorption) decreased as the frequency of regeneration was increased. Experiment was further performed to evaluate the performance of the treatment scheme of chemical precipitation by ferrous iron waste followed by biological aerated filter (BAF). The overall removal efficiency in the system increased up to 80% and 90% for total phosphate (TP) and soluble phosphate (SP), respectively, and the corresponding effluent concentrations were detected below 2 mg/L and 1 mg/L for TP and SP, respectively. However, short-circuit problem was still unsolved operational consideration in this system. The practical concept applied in this study will give potential benefits in achieving environmentally sound wastewater treatment as well as environmentally compatible waste disposal in terms of closed substance cycle waste management.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.34-40
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• 2012

This research has looked into the treatment process of wood waste generated from industrial waste within the region and in order to modify the problem that may occurred during the mass balance were analyzed for development of suitable solid waste recycling network regionally. As as result, quite amount of wood waste are being transferred to another region, even though a treatment facility's capacity could bear the total amount of waste generated within the area. Although the wood waste could be treated locally, it is analyzed that amount of wood waste are being transferred due to inefficient and irrational processing system between regions. It is assumed that $CO_2$ generated and loss of unnecessary fuel cost from these inefficient system is quite a lot and in order to modify this disorganized system, it will not inevitable to treat the waste based on the characteristics of each regions. Also, the wood waste recycling system should be studied with the efficient, environmental friendly processing and delivering network by minimized transfer distance and local systemizing the waste treatment system.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.3
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• pp.285-299
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• 2006

At the end of 2005, 443 nuclear reactors were operating in 32 countries worldwide. They had provided about 3,000 TWh, which was just over 16 percent of global electricity supply. With the generating capacity of 368 GWe in 2004, the spent fuel generation rate worldwide, now becomes at about 11,000 tHM/y. Projections indicate that cumulative amounts to be generated by the year 2020, the time when most of the existing NPP will be closed to the end of their licensed lifetime, may be close to 445,000 tHM. In this regard, spent fuel management is a common issue in all countries with nuclear reactors. Whatever their national policy and/or strategy is selected for the backend of the nuclear fuel cycle, the management of spent fuel will contribute an impending and imminent issues to be resolved in the foreseeable future. The 2nd Review Meeting of the Contracting Parties to the Joint Convention was held in Vienna from 15 to 24 May 2006. The meeting gave an opportunity to exchange information on the national policy and strategy of spent fuel management of the Contracting Parties, to discuss their situations, prospects and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should be taken. In this paper, an overview of national and global trends of spent fuel management is discussed. In addition, some directions are identified and recent activities of each Member States in the subject area are summarized.

• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.469-482
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• 2018

This research has developed the criteria and index for systematically and objectively assessing the quality of river water by fixing the various factors that affect Gyeongin ARA waterway's water quality through analysis with the Delphi Technique and analytic hierarchy program (AHP) Method. Based on the results, the highest criteria are, in order of importance, physical and environmental factors 28%, administrative factors 26%, natural fixed factors 26% and finally, cultural and social factors 20%. The three dimensions of the criteria show that for the internal physical and environmental factors, the most important are the loss of self-purification capacity, and the external factors are Gulpocheon and the sludge deposit due to Gyulhweon-weir the bridge. The facility factor in management was affected by the coagulation and waste water disposal facilities. The problem for the policy and institutional factors was seen in the regulatory area. The aquatic ecology/ point pollution source for the natural fixed factors show that it is due to the polluted water of Gulpo-cheon and the living environment/ non-point pollution source is shown through the inflow water from other rivers. Cultural and social factors show that the economical causes were due to the cargo and passenger flight operations and the external factors of having a lack of sewage treatment equipment have an importance effect. In order to estimate the order of priority through logical evidence and objectivity, future research must be continued on the evaluation indexes to measure the specific methodology and technique needed to improve the Gyeongin ARA Waterway.

• Journal of Radiation Protection and Research
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• v.21 no.4
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• pp.313-327
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• 1996

As an at-reactor(AR) storage method o( spent fuel, there are horizontal concrete module type, metal storage cask type, concrete storage cask type, dual purpose (transportation and storage) cask type and multi-purpose (transportation, storage and disposal) cask type. All other types except multi-purpose one have been already used for AR dry storage of spent fuels after obtaining operation license in various foreign countries. Also the development of multi-purpose type has been continued for operation license. In America, Japan, Germany, Canada, Spain, Switzerland, and Czech Republic, etc., AR dry storage facilities are under operation or on propulsion, and spent fuels are transported to interim storage facility or reprocessing plant after dry storage at reactor temporarily. At Wolsung site, in case of Korea, concrete silo type has already been introduced, and it is believed to be inevitable to store spent fuels at reactor temporarily, considering the reality that storage capacity of spent fuel is approaching to the limit in some nuclear power plants. In this report, the system characteristics, design requirements, technical standards and status of AR storage system, which is suitable for domestic site such as Kori, have been studied. In most cases, the licensed period of storage cask is limited up to 20 years and the integrity of material and maintenance of leaktightness are required during the whole service life.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.585-597
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• 2008

The aim of this study was to find an analytic solution to the problem of determining the optimal capacity (lot-size) of a batch-storage network to meet demand for a finished product in a system undergoing random failures of operating time and/or batch material. The superstructure of the plant considered here consists of a network of serially and/or parallel interlinked batch processes and storage units. The production processes transform a set of feedstock materials into another set of products with constant conversion factors. The final product demand flow is susceptible to short-term random variations in the cycle time and batch size as well as long-term variations in the average trend. Some of the production processes have random variations in product quantity. The spoiled materials are treated through regeneration or waste disposal processes. All other processes have random variations only in the cycle time. The objective function of the optimization is minimizing the total cost, which is composed of setup and inventory holding costs as well as the capital costs of constructing processes and storage units. A novel production and inventory analysis, the PSW (Periodic Square Wave) model, provides a judicious graphical method to find the upper and lower bounds of random flows. The advantage of this model is that it provides a set of simple analytic solutions while also maintaining a realistic description of the random material flows between processes and storage units; as a consequence of these analytic solutions, the computation burden is significantly reduced.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.428-432
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• 2013

From the forest areas in Chungbuk, large amounts of wood wastes by pruning are generated, however most of them considered as by-products are not treated properly with no disposal options. In this work, among diverse wood wastes such as Quercus variabillis, Juniperus chinensis, Larix kaemoferi, and Pinus densiflora, Juniperus chinensis was found to be more effective biosorbent for the removal of lead ions than other wood wastes. Also, the enhancement of lead removal efficiency from the aqueous phase was investigated using Juniperus chinensis waste. It was observed that the optimal initial pH to increase the removal efficiency of 20 mg/L lead ions was 4.0 and the optimal dosage concentration with regard to the biosorbent for the enhanced removal of 50 mg/L lead ions was 0.6 g/100 mL. In addition, chemical treatment of Juniperus chinensis waste with sulfuric acid was required to improve the adsorption capacity for high lead concentrations (over 100 mg/L). When Juniperus chinensis waste was chemically treated with 6 M sulfuric acid, the adsorption quantities of lead ions were 180, 340, and 425 mg/g with regard to 200, 400, and 500 mg/L lead ions concentrations, respectively. These results indicate that the practical biosorbent technology developed in this study is a highly efficient method to treat the lead ion from an aqueous solution.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.69-74
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• 2009

In Korea, large amounts of chestnut shell as by-products are produced from food industries. However, most of the by-products exist with no disposal options. Biosorption uses biomass that are either abundant or wastes from industrial operations to remove toxic metals from water. Objective of this research was to evaluate the feasibility of using chestnut shell as by-products for removal of metal ions(Pb, Cu and Cd) from aqueous solution. The chestnut shell was tested for its efficiency for metal removal by adopting batch-type adsorption experiments. The adsorption selectivity of chestnut shell for metals was Pb > Cu > Cd at solution pH 5.5. The Langmuir isotherm adequately described the adsorption of chestnut shell for each metal. Using The maximum adsorption capacity predicted using Langmuir equation was 31.25 mg $g^{-1}$ 7.87 mg $g^{-1}$ and 6.85 mg $g^{-1}$ for Pb, Cu and Cd, respectively. Surface morphology, functional group and existence of metals on chestnut shell surface was confirmed by FT-IR, SEM and EDX analysis. The chestnut shell showed an outstanding removal capability for Pb compared to various adsorbents reported in the literatures. The overall results suggested that chestnut shell might can be used for biosorption of Pb from industrial wastewater.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.203-213
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• 1998

To investigate impacts of waste disposal on the marine environment for 9 years since dumping activity commenced in the Yellow Sea, chemical analysis of seawater has been done in and around the ocean dumping site. Results show that biogeochemical changes have occurred locally in the dumping area compared with the reference area, resulting in low dissolved oxygen saturation, low pH, and high accumulation of nutrients in the bottom layer. According to cluster analysis, chemical environment of the study area can be largely divided into surface layer and bottom layer, and again the bottom layer can be divided into that of dumping area where nutrients are accumulated and that of reference area. Low pH, low dissolved oxygen, high COD and accumulation of nutrients mainly characterize the dumping area. Average concentration of total inorganic nitrogen in the bottom layer below the thermocline has increased from $3.7{\mu}M$ to $9.5{\mu}M$, 250% accumulation in the dumping area since 1988. Therefore, the present results clearly show that the dumping site of Yellow Sea has received excessive sewage input beyond the environmental assimilatory capacity during the last decade. It may result in serious aggravation of seawater quality and basic ecosystem, and devastation of overall fishing grounds of Yellow Sea in the near future.