• Journal of the Korean Applied Science and Technology
• /
• v.21 no.2
• /
• pp.124-131
• /
• 2004

The adsorption of heavy metals in the waste water carried out on the various domestic clays and waste pottery. The effect of parameters such as pH, temperature, adsorption time and coexisting cations on the adsorption ability and characteristics were investigated to find out whether the clays could be used as adsorbents. Adsorption equilibrium was reached within 20 minutes on all the clays. The optimum pH was found to be above 5. When other cations such as Cu(II) or Zn(II) coexisted with Pb(II), the adsorption amount of Pb(II) decreased because of competing adsorption.

• Applied Chemistry for Engineering
• /
• v.5 no.6
• /
• pp.917-924
• /
• 1994

In this paper, we briefly introduce applications of optimum de-inking agent by waste-paper recycling stimulation technology. From the aspects of environmental protection and efficient use of natural sources requirement of recycle paper and higher quality pulp will be increasing. By developement of high-performance de-inking agents and its system, we would like to contribute for advance of waste paper treatment technology and higher quality pulp recycling.

• Ocean Science Journal
• /
• v.40 no.2
• /
• pp.91-100
• /
• 2005

Bioassay using the marine bacteria, Vibrio fischeri and rotifer, Brachionus plicatilis, and chemical analyses were conducted to assess the toxicity of the various sewage sludges, one of the major ocean dumped materials in the Yellow Sea of Korea. Sludge elutriates extracted by filtered seawater were used to estimate the ecotoxicity of the sludge. Chemical characterization included the analyses of organic contents, heavy metals, and persistent organic pollutants in sludge. Bacterial bioluminescent inhibition (15 min), rotifer mortality (24 hr) and rotifer population growth inhibition (48 hr) assay were conducted to estimate the sludge toxicity. EC50 15 min (inhibition concentration of bioluminescence after 15 minutes exposed) values by Microtox(R) bioassay clearly revealed different toxicity levels depending on the sludge sources. Highest toxicity for the bacteria was found with the sludge extract from dyeing waste and followed by industrial waste, livestock waste, and leather processing waste. Clear toxic effects on the bacteria were not found in the sludge extract from filtration bed sludge and rural sewage sludge. Consistent with Microtox(R) results, rotifer neonate mortality and population growth inhibition test also showed highest toxicity in dyeing waste and low in filtration bed and rural sewage sludge. High concentrations of persistent organic pollutants (POPs) and heavy metals were measured in the samples from the industrial wastes, leather processing plant waste sludge, and urban sewage sludge. However, there was no significant correlation between pollutant concentration levels and the toxicity values of the sludge. This suggests that the ecotoxicity in addition to the chemical analyses of various sludge samples must be estimated before release of potential harmful waste in the natural environment as part of an ecological risk assessment.

• Journal of Energy Engineering
• /
• v.26 no.3
• /
• pp.97-104
• /
• 2017

In this study, waste tire rubbers were pyrolyzed in a lab-scale pyrolysis plant equipped with a fluidized bed reactor in a temperature ranges of $450-650^{\circ}C$. The main object of this work is to investigate the properties of pyrolysis oil with reaction temperatures and the behavior of sulfur in the products when waste polypropylene was added for co-pyrolysis. The maximum yield of oil was about 52wt.% at the reaction temperature of $456^{\circ}C$. From GC-MS analysis, the pyrolysis oils consisted mainly of limonene, toluene, xylene, styrene, trimethylbenzene, methylnaphthalenes and some heteroatom(sulfur and nitrogen)-containing compounds. The addition of waste polypropylene resulted in decrease in sulfur contents of the pyrolysis oils.

• Applied Chemistry for Engineering
• /
• v.23 no.2
• /
• pp.195-203
• /
• 2012

Recycling method of waste LCD glass is the essential process for developing the total recycling process of LCD pannel. Pulverizing of LCD glass, determination of proper carbonacious foaming agent, the properties of residue from the recovery of valuable materials through an acid leaching process and the feasibility for the foaming of the residue obtained from leaching for indium and tin recovery were investigated for the developing of recycling method of waste LCD glass as industrial feed materials, such as heat insulation materials, sound absorbing materials, carrier of water treatment. Waste LCD glass could be pulverized finely for foaming process. Natural graphite was proper agent for foaming of the residue and the foaming technology of LCD glass would be effective recycling alternatives.

• Journal of Environmental Impact Assessment
• /
• v.6 no.2
• /
• pp.123-135
• /
• 1997

The solid waste incineration facilities which cause environmental pollution. And those are some kind of loathing facilities for residents who do not want it. This problem could be solved by location feasibility study. The purpose of location feasibility study was to determine one site out of three candidate sites. This study which was done by the law, environmental and economic factor was considered for optimum site selection. Comparative evaluation among the candidate sites was done by ordinal scale and thus the optimum site was selected.

• Journal of the Korean Professional Engineers Association
• /
• v.15 no.2
• /
• pp.43-44
• /
• 1982

What I would like to expect about this mater is that Korea would develop unique techniques of the waste water which are most suitable to social and other relevant conditions of that country, not entirely following models of sewerage construction of U.S.A. or European countries or Japan. Some cements will be made in the followings: (1) The investigation for the diffusion of seperated simple public sewerag, not the large scale sewerage treatment plant. (2) The plan for non-mixed treatment of lining waste water and industrial waste water. (3) Suggestion for "a man of ability" at the university education to cultivate a technologist of facilities and the elemental watchman at the sewerage maintenance.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1992.10a
• /
• pp.69-74
• /
• 1992

The characteristics of the landfill of coal ash and ironwork wastes are investied by performing the basic geotechnical experiments and groundwater quality analyses in the landfills. The results show that the waste materials themselves have good characteristics that can be used as reclamation materials. However, landfills need either some ground improvement or costly foundation and excavation methods to be used as construction sites, because of the careless management during the period of waste disposal.

• Analytical Science and Technology
• /
• v.26 no.4
• /
• pp.276-286
• /
• 2013

This study was performed to investigate the contents characteristics of hazardous oil wastes and wastes of liquid fuels from different industrial process. In order to establish a hazardous waste list, samples of various industrial discharge have been analyzed for 16 non-regulated inorganic hazardous substances (i.e., Cu, Pb, Cd, CN, Hg, As, T-Cr, $Cr^{6+}$, Sb, Ni, F, V, Ba, Zn, Be, Se). In more detail, hazardous waste samples including waste hydraulic oils, waste engine, gear and lubricating oils, waste insulating and heat transmission oils, bilge oils, oil/water separator contents processing were collected from 37 workplaces and analyzed. We observed that the most of the inorganic substances exceeded the proposed criteria in many samples. Especially the concentration of Sb in heat transmission oil, bilge oil and gear & lubricating oils were ranged from 6 to 419 mg/kg whereas the proposed criteria is 50 mg/kg. The assessment result of hazardous waste in Korea according to the EWC showed that the out of 24 processes, 16 belongs to absolute entry and 8 belongs to mirror entry. In conclusion, we expect the outcome of this study to align the classification system of hazardous waste management in South Korea with international legislations, and consequently contribute to reduce environmental pollution as well as health risks by toxic wastes.

• Applied Biological Chemistry
• /
• v.27
• /
• pp.68-79
• /
• 1984

An increased population and rapidly expanding industrial development have led to enormous amounts of various domestic and industrial wastes. The proper disposal of ever-increasing wastes is a growing global problem. Land treatment is one of the rational approaches that are environmentally safe and economically practical. It has long been practised in many sites. Recycling of industrial wastes on agricultural land can provide better possible means for maintaining environmental quality and utilizing waste-resources. Even though industrial wastes are beneficial as soil amendment and fertilizer, they have some limitation on land application because of wide variability as well as physicochemical problem in their composition. A direct application of solid and liquid wastes on land is being practised in Korea and some experimental results are presented. The direct application of fermentation waste on rice resulted in a 6 percent yield increase. Another organic residue from glutamic acid fermentation is widely used not only as a direct application as a liquid fertilizer but also for a raw material of organic compound fertilizer. These wastes are much promising as sources of plant nutrients, since they have large amounts of nutrients, especially nitrogen with few toxic metals. On the other hand, fertilizers developed from inorganic industrial wastes include calcium silicate, calcium sulfate and ammonium sulfate. The calcium silicate fertilizer simply produced from slag, by-product of iron and steel manufacturing plant is one of the most successful example of the conversion of wastes to fertilizer and slag production capacity totals to over three million MT/year. About 200,000 MT of calcium silicate fertilizer is currently applied in the paddy rice every year. Calcium sulfate, a waste from the wet phosphoric acid process is to some extent used as a filler of compound fertilizers but quite large quantites are directly applied for the reclamation of tidal flat.