• Resources Recycling
• /
• v.11 no.5
• /
• pp.24-29
• /
• 2002

In this study, to improve the color of iron oxide from waste pickling acid at the cold rolling mill, the quality control technologies especially about color were investigated on the spray roaster and iron oxide powder. At the operation condition of the spray roaster, the charge amount of waste acid per hour, temperature, numbers of spray nozzle were investigated. At admixing process, titanium oxide, silica, goethite were tested. Color character of iron oxide can be improved by process control at spray roaster and by admixing process at a pigment factory Iron oxide from results of this study is enough to use as the colorant of concrete product.

• Journal of Mechanical Science and Technology
• /
• v.17 no.10
• /
• pp.1485-1495
• /
• 2003

We investigate the triboelectrostatic separation of polyvinylchloride (PVC) from mixed plastics in the laboratory scale triboelectrostatic separation system. The flow and electric fields in the precipitator are obtained from the numerical solution of finite volume method. Using these flow and electric fields, we solved the particle motion equation considering the inertia, drag, gravity and electrostatic forces acted on the particles. The particle trajectories are obtained using a Lagrangian method as a function of different important variables such as Reynolds number, Stokes number, electrostatic force, electric charge and electric field distribution, inclined angle of plane electrodes, particle rebounding, particle charge decay rate after impact on the electrode surface, etc., in order to determine the optimal design conditions. The present predicted results for the cumulative yield represent well the experimental ones.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2002.05a
• /
• pp.34-45
• /
• 2002

The new measuring method of micro-stickies considering both the effects of charge neutralization and evaporation of process water was developed by KRICT PPRC. By the new KRICT method, the contamination of metal dryer surface and other machine clothes could be estimated quickly and simultaneously. According to this study, it could be confirmed that the novel method is a useful one for the evaluation of several treatments regarding the reduction of stickies troubles.

• Journal of environmental and Sanitary engineering
• /
• v.10 no.1
• /
• pp.35-44
• /
• 1995

The study was carried out to investigate on the response of environmental sanitation problems in action of the volume based waste charge system in Seoul The responses from the 346 persons who dwelled in Seoul was stimulatively answered, this system was considered as a successful on 70.5% of total answers, but little portion(29.4 % ) of those was unknown on the mean of this system. And we knew that this system was need to the communication and education through the press media about this one. After the action of the volume based waste system, the volume of refuse discharged in a day was decreased 30 ∼40% than before. In the problems of environmental sanitation after this system, the number of sanitary insect( cockroach etc ) and rat was decreased, also the production of orders and dust caused by refuse was decreased in comparison with those before. This results were considered that the Separate Collection should be perfectly performed. In response, the regular envelope of refuse was serious problems, the improvement for this one was demanded. The kind of difficult refuse treated was waste rubbers> electric products > furniture> foodstuffs> bottles, cans> papers, pulps etc, and the next proposal for this system should be prepared. Conclusively, the volume based waste charge system should be remarkable system In terms of resources recycling as well as wastes reduction. Above all in order to conform this system the separate collection system should be systematically performed, the next improvable proposal of the detailed methods in this system should be prepared.

• Journal of the Korean housing association
• /
• v.13 no.3
• /
• pp.1-9
• /
• 2002

Desolation of the earth due to environmental pollution is rising as a world wide problem and concern. At this point we need to look into the problem and set up a direction for the future. In order to reveal the change of garbage problems in our county's civil life, a researcher analyzed 369 garbage related articles from the first edition of Dong A Ilbo up to 1990. The following is the result of data from garbage related articles. It is organized by age and era(10 years). 1) Number of articles by year roses in 1921 after first publication of garbage problem article. In the 1930s, the number of articles drastically increased in 1937. From then on, the number of articles declined until early 1970s but roses again from 1978. 2) Yearly change in articles was a mere 1.2 columns in between 1920 to 1960. In the 1970's, relative importance increased and over 5 columns were published. Articles rose in the 1980s with over 3.4 and 5 columns. 3) The contents of the articles can be classified into cleaning problems, collecting and transporting, expenses, and recycling. Garbage disposal problems continued until the 1970s. Regarding garbage collecting problems, form of collecting container and location was discussed. Laws were revised after garbage disposal areas were discussed in the 1920s. Expenses were levied from the 1930s and rising cost and double charge problems were subjected. Garbage recycling began in the 1920s and continued until 1900s.

• Journal of ILASS-Korea
• /
• v.7 no.2
• /
• pp.7-15
• /
• 2002

A particle flow visualization, electrostatic charging measurement and separation of triboelectrically charged particles in the external electric field by a fluidized bed tribocharger are conducted for the removal of PVC particles from mixed waste plastics. The laboratory-scale triboelectrostatic separation system consists of the fluidized bed tribocharger, a separation chamber, a collection chamber and a controller. PVC and PET particles can be imparted negative and positive surface charges respectively due to the difference of triboelectric charging series between particles and particles in the fluidized bed tribocharger, and can be separated by passing them through an external electric field. To visualize these charged particles, He-Ne laser is used with cylindrical lenses to generate a sheet beam. In the charging measurement, the particle motion analysis system (PMAS), capable of determining particle velocity and diameter. is used to non-intrusively measure particle behavior in high strength electric field. The average charge-to-mass ratios of PVC and PET particles are $1.4\;and\;1.2{\mu}C/kg$, respectively. The highly concentrated PVC (91.9%) can be recovered with a yield of about 96.1% from the mixture of PVC and PET materials for a single-stage processing. The triboelectrostatic separation system using the fluidized tribocharger shows the potential to be an effective method for removing PVC from mixed plastics for waste plastic recycling.

• Korean Journal of Human Ecology
• /
• v.18 no.6
• /
• pp.1247-1256
• /
• 2009

The purpose of this study was to make a close inquiry into the types and characteristics of social responsibility of fashion brands, perceived by consumers in the condition that a systematic frame of social responsibility of fashion brand didn't exist. To achieve the purpose, the study carried out literary survey and FGI (Focus Group Interview) which were qualitative research methods. The study carried out interviews with 9 experts majoring in fashion and 4 staff members in charge of fashion companies. The results of the study were as follows: (1). There were five types of social responsibility activities of fashion brands: fund raising activities, scholarship/cultural volunteer activities, consumer protection activities, recycling/environment-friendly activities, and ethical responsibility activities. (2). Out of the social responsibility of fashion brand, recycling/environment-friendly activities was valued above everything else. It implicates that we should pursue economic profits and sustainability at once by recognizing the importance of environmental management and improving enterprise management. As stated above, it is thought that fashion brand companies should fulfill their social responsibility strategically for long-term profits of fashion brand by grasping and improving the present conditions of social responsibility of fashion brand.

• Resources Recycling
• /
• v.22 no.1
• /
• pp.29-35
• /
• 2013

The study on the recovery of Nylon from a radiator of End-of-Life Vehicle was conducted by using triboelectrostatic separation technique. For the effective separation of the sample(Nylon, PP glass), charge polarity and amount of each sample with various charging materials have been investigated by faraday cage. And then, charging material was selected as carrying out basic separation experiments with materials that can be possible to polarize samples. Finally, the continuos type triboelectrostatic separator was developed with selected charging material and the recovery possibility of the sample was confirmed as carrying out various separation experiments.

• Environmental and Resource Economics Review
• /
• v.21 no.1
• /
• pp.175-210
• /
• 2012

As London and post-Koyto protocols presumably affect emission of organic waste in Korea in 2012, appropriate treatment of organic waste becomes very important. Organic wastes are regarded as non-point pollutants. It has been criticized that direct emission charges on the emission of non-point pollutants are not effective due to the high uncertainty in the relationship between pollution sources and pollution levels. This study suggests indirect emission charges on production of livestocks or consumption on foods. Furthermore, it is assumed that revenue from the emission charges will be recycled to support biogas production. Biogas can be fueled to produce energy. In order to evaluate potential economic and environmental impacts of recycling the indirect emission charges on organic wastes, a static CGE model was developed. Simulation results of emission charges on the production of livestock show that livestock, agriculture, and food industry will confront relatively high burden while emission charges on consumption of food will affect more broadly and consumers will suffer more. Production charge on livestock sector will lead to higher reduction in GDP and total expenditure relative to the consumption charge. GHGs reduction effect was higher for the consumption charge relative to the production charge. Synthetically, consumption charge on food sector is more desirable as an alternative charge for the emission of organic wastes.

• Journal of the Korean Ceramic Society
• /
• v.47 no.1
• /
• pp.86-91
• /
• 2010

Among various fuel cells, solid oxide fuel cells (SOFCs) offer the highest energy efficiency, when taking into account the thermal recycling of waste heat at high temperature. However, the highest efficiency and lowest pollution for a SOFC can be achieved through the sophisticated control of its constituent components such as electrodes, electrolytes, interconnects and sealing materials. The electrochemical conversion efficiency of a SOFC is particularly dependent upon the performance of its electrode materials. The electrode materials should meet highly stringent requirements to optimize cell performance. In particular, both mass and charge transport should easily occur simultaneously through the electrode structure. Matter transport or charge transport is critically related to the configuration and spatial disposition of the three constituent phases of a composite electrode, which are the ionic conducting phase, electronic conducting phase, and the pores. The current work places special emphasis on the quantification of this complex microstructure of composite electrodes. Digitized images are exploited in order to obtain the quantitative microstructural information, i.e., the size distributions and interconnectivities of each constituent component. This work reports regarding zirconia-based composite electrodes.