• Journal of Environmental Science International
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• v.16 no.8
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• pp.929-939
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• 2007

Red mud is a waste generated by the aluminium industry, and its disposal is a major problem for this industry. Red mud has a reddish-brown color and superfine particle characteristics. So, it can be a promising pigment admixture for concrete industry. An experimental study was conducted to investigate the potential use of red mud in color concrete. The micro structures of red mud and iron oxide pigment such as porosity, pore size distribution, diameter of particle were analyzed with the aid of SEM, X-ray diffraction(XRD), and the infrared absorbance. Tests on physical properties of color concrete, such as strength, slump, early shrinkage crack patterns, and color characteristics were carried out and the results were reported in this paper.

• Environmental Engineering Research
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• v.20 no.1
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• pp.99-104
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• 2015

The purpose of this study is to evaluate the performance of forward osmosis (FO) system for harvesting microalgae cultivated in secondary sewage effluent. Microalgae species used in this study were chlorella sp. ADE4. The drawing agents used for forward osmosis system were seawater and concentrate of sea water reverse osmosis (SWRO) system. Chlorella sp. ADE4 cultured in secondary sewage effluent illustrated moderate efficiency in removal of total nitrogen (TN) (68%) and superior performance in total phosphorus (TP) removal (99%). Comparison of seawater and SWRO concentrate as drawing agent were made in FO membrane separation of the microalgae. The result from this study depicts that SWRO concentrate is strong drawing agent in FO membrane system providing an average dewatering rate of $4.8L/(m^2{\cdot}hr)$ compared to seawater with average dewatering of $2.9L/(m^2{\cdot}hr)$. Results obtained from this study indicated that FO system could be viable option for harvesting the microalgae for further biodiesel production. SWRO concentrate as a drawing agent could be very important finding in field of membrane technology for disposal of SWRO concentrate.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.2
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• pp.81-88
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• 2008

There are increasing public concerns that the disposal of most synthetic carbon-based plastics is a great threat to the environment. These have led to intensive research and development of degradable plastics, such as biodegradable plastics, photodegradable plastics, and multi-degradable plastics. Although these degradable plastics may not completely replace common synthetic plastics, these minimize environmental impacts caused by non degradable plastics. Photodegradable plastics are synthetic polymers into which have been incorporated copolymers or light-sensitive additives to weaken the structural bonds in polymer chains when exposed to UV radiation. A better understanding of photodegradable plastics, which also play an important role in the degradation of multi-degradable plastics, will expand the usage of degradable plastics. The aim of present article is to review the formation, degradation mechanism and properties of photodegradable plastics.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.365-370
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• 2009

LCA is a tool to support for making decisions by offering information of environmental aspects of products or services. It can be used to make decisions to consumers and NGOs as well as government and enterprises. LCA evaluates the environmental aspects throughout the entire life cycle of a product. Therefore it can quantify and assess environmental impacts from raw material acquisition, manufacturing, distribution, use and disposal to end of life and recycling. The demands of the recycling rate increase and the use of suitable materials for RoHS, REACH, WEEE, ELV which are linked trade with environmental regulation have increased the worldwide. Global warming is the critical challenge of the world facing. And under post-Kyoto protocol each country has to prepare for target reduction, so it became essential to save energy and resources. In addition that, the carbon mark has been run as the way of showing example of CO2 reduction in domestic and it will be extended gradually. And also through the introduction of Eco-label, environmentally-friendly product will be promoted. When those systems are operated, global warming gases (i.e. CO2) can be calculated throughout the entire life of the products by LCA. And the environmental impacts such as harmful material emission in the process of manufacturing, energy consumption, distribution and so on, can also be assessed. Therefore, The basic concepts of LCA technique and various cases and the practical application in the future will be review in this study.

• Composites Research
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• v.36 no.4
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• pp.264-269
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• 2023

Spent coffee grounds (SCG) are a ubiquitous byproduct of coffee consumption, representing a significant waste management challenge, as well as an untapped resource for economic development and sustainability. Improper disposal of SCG can result in environmental problems such as methane emissions and leachate production. This study aims to investigate the physicochemical properties of SCG and their potential as a reinforcement material in polypropylene (PP) to fabricate an eco-friendly composite via extrusion and injection molding, with SCG filler ratios ranging from 5-20%. To evaluate the effect of SCG on the morphological and mechanical properties of the bio- composite, thermogravimetric analysis, SEM, tensile, flexural, and impact tests were conducted. The results demonstrated that the addition of SCG lead to a slight increase in brittleness of the composite but did not significantly affect its mechanical properties. Impressively, the presence of a significant organic component in SCG contributed to the enhanced thermal performance of PP/SCG composites. This improvement was evident in terms of increased thermal stability, delayed onset of degradation, and higher maximum degradation temperature as compared to pure PP. These findings suggest that SCG has potential as a filler material for PP composites, with the ability to enhance the material's properties without compromising overall performance.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.906-917
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• 2022

This study aimed to compare differences according to categories of fishery and marine environmental policies for the (estimated) amount of fishery waste generated by fishing, and to analyze the correlation between associated independent and dependent variables. The independent variables were divided into three dif erent sectors. The first sector included precautionary policies that observed eco-friendly fishing support program, institutional prevention activities, and physical barriers installation. The second sector with the current management policies included the relevant vessel operations, establishment of fishery order, fishery restructuring, and fishery ground clean-up. Thirdly, post-response policies comprised the litter purification from river to shoreline, the collection and removal of marine, sedimentary, and floating debris, purchasing salvaged debris generated while fishing, fishery waste disposal, and repairing damage caused by marine litter. The indicator used was the settlement amount by each program. The dependent variable was the estimated amount of fishery waste and the indicator was the sum of the loss of traps and gill nets and the loss of their appendages. According to the results of Kruskal-Wallis Test, the estimated amount of fishery waste was highest in the East Sea in terms of sea area and the highest in the Si(city) according to basic local municipality. The settlement amount related to the marine environment services was largest in the Gun(county). Further, there were significant differences between Gun(county) and the other regions(Si(city) and Gu(autonomous district)) with respect to most variables. The variables related to the estimated amount of fishery debris were the project purchasing salvaged debris generated while fishing and fishery waste disposal program in the post-response policies.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.4
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• pp.61-74
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• 2012

Industrial complexes in Korea have been vigorously established by economic development plan and development policy of industry in 1960s. Recently, Korean government has promoted Eco Industrial Park (EIP) project to recycle by-products and wastes in industrial park In this study, we analyzed the physical and chemical properties for the sludges discharged from A industrial complex. And we investigated the economic feasibility and environmental impact of sludge to energy facilities. The analysis results indicated that the petrochemical industry were 92% in sludge production, the highest treatment amount was landfill, followed by incineration and recycling and then ocean disposal. Wastewater sludge and process sludge samples are collected and analyzed to use as basic data on economic feasibility and environmental impact. Weighted average heating value of sludge samples was 3,891kcal/kg. Based on this data, installation and operation costs, operation returns of operating the drying facility are estimated, compared with cogeneration facility. And this study examines how the payback period of each simulation(total 8 case) with the important parameter changes. As a result, it was found that what needs the shortest payback period is 3years with connection of drying facility and cogeneration facility based on the government's financial subsidy system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.149-154
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• 2007

The zinc prosphate film treatments used to lubricating treatment of mostly cold forging processes. But there are several problems happened to lubricating treatment process such as happening harmful environment on person, complex lubrication processing occurring in energy and time consumption, eco-destructive and chemical by-product generation, the needs of waste disposal etc. As a result, a water-soluble lubricant was developed to replace the perfect or some of the zinc prosphate film in the world. In order to solve these problems, this study evaluated the performance of the typical water-soluble. In this study, for these requirement inquiry of two part. First, about possibility of replace zinc phosphate lubricant, quantitatively evaluation developed of water-soluble lubricant for cold forging vs zinc phosphate lubricant. Second, About optimization of coating Process use to equipment with practicable automatic coating Process. The performance evaluation of these lubricants was conducted using the double cup extrusion test and spike forging test. With the use of the commercial FE code DEFORM, friction factor calibration curves, i.e. cup height ratio vs. punch stroke and spike height vs. punch stroke, were established for different friction factor values. By matching the cup height ratio and the punch stroke and spike height vs. punch stroke from experiment to that obtained from FE simulations, the friction factor of the lubricants was determined. Survey of comparative analysis use to SEM that sprayed lubricant surface structure of grain shape and characteristic of lubricant performance based on grain shape and deformed lubricant surface expansion. As a result, developed lubricant were found to perform comparable to or better than zinc phosphate. And thought this result, innovatively cope with generated problem of existing lubrication process.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.477-482
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• 2008

A variety of bacterial strains were isolated from waste disposal sites of Uttaranchal, India, and some from artificially developed soil beds containing maleic anhydride, glucose, and small pieces of polyethylene. Primary screening of isolates was done based on their ability to utilize high- and low-density polyethylenes (HDPE/LDPE) as a primary carbon source. Thereafter, a consortium was developed using potential strains. Furthermore, a biodegradation assay was carried out in 500-ml flasks containing minimal broth (250ml) and HDPE/LDPE at 5mg/ml concentration. After incubation for two weeks, degraded samples were recovered through filtration and subsequent evaporation. Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis (TG-DTG-DTA) were used to analyze these samples. Results showed that consortium-treated HDPE (considered to be more inert relative to LDPE) was degraded to a greater extent (22.41% weight loss) in comparison with LDPE (21.70% weight loss), whereas, in the case of untreated samples, weight loss was more for LDPE than HDPE (4.5% and 2.5%, respectively) at $400^{\circ}C$. Therefore, this study suggests that polyethylene could be degraded by utilizing microbial consortia in an eco-friendly manner.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1236-1251
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• 2015

This study examined understanding and attitude of sustainable development(SD) of 38 college students in a nuclear power plant construction after education for sustainable development(ESD) through panel discussion. The results were as follows: First, after lesson 66% of students were expected that SD is possible if scientific technology is developed and a frugal life for the protection of environment is carried out. However, the remaining students regarded SD as an ideal concept, because they thought it is not possible to pursue environmental sustainability and socio-economic development simultaneously. Second, students' opinions in the evaluation of constructing a nuclear power plant in three aspects(environment, society and economy) before and after panel discussion were changed as follows; 1) After panel discussion, the objectors increased to 21% in economic evaluation, while the supporters increased to 11% in environmental evaluation. 2) Students majoring in engineering or natural sciences changed their opinions to agree in environmental evaluation because they considered a nuclear power plant safe and eco-energy. However students majoring in social science/business or liberal arts/arts changed their opinions to disagree in economic evaluation because they considered a nuclear power plant as high-cost energy when assessing danger-accidents cost, public consensus cost, operation and maintenance cost, and waste disposal cost. 3) This change of decision-making in students majoring in social science/business or liberal arts/arts after panel discussion was statistically significant(p<0.05). Implications of panel discussion as a teaching and learning method in ESD are also discussed.