• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.256-261
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• 1995

Large-scaling recycling of demolished concrete will concrete will contribute not only to the solution of a growing waste disposal problem, it will also help to consweve natural resoures of sand and gravel and to secure future supply of reasonly priced aggregates for building and other construction purposes within large urban areas. Because recycled aggregate particles consits of substantial amount of relatively soft cement paste component, it is less resistant to mechanical actions. With this view in mind, to obtain a reference data for the development of recycling system and to a basic data the guiedline of recycled aggregate concrete construction and engineering properties of recycled aggregate concrete according to the factors, such as blending ratio of recyced aggregete with the natural aggregate, addition to the factors, such as blending ratio of recycled aggregete with the natural aggregate, addition of flyash, water coment ratio.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.805-810
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• 2003

It is the real circumstance in the country that not only the data and special books but also people who have an expert knowledge are short of the field of the study about plastic wastes, so that to build the Database carrying out gathering info of that is the present question obviously. The business on recycling plastic, for some reason or other, is one of the best ways as called bright prospect industry to prevent environmental pollution and obtain economical outcome by using limited resources. Plastic wastes with construction industry especially using Polymer may have a good effect on the environment and human beings and have a fine view to produce functional and Eco-friendly concrete as well. In this study, Chemical resistance and Water Absorption test in Polymer concrete using bentonite as a shrinkage control agent was made an experiment by comparing with influence on concrete strength and used to offer some valuable data about Polymer concrete.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.359-366
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• 2003

Ecological society and energy conservative systems has become a subject of world wide attention. To examine the technologies of such systems as resource recycling society, this study is proposed for using rainwater as energy source and water resources in urban area. Useful informations for planning of utilizing rainfall as energy source, water resources, emergency water and controlling flood are discussed with model systems in urban area. It is calculated that the rate of utilizing rainwater, amounts of utilizing rainwater, substitution rate of supply water, amounts of overflow rainwater according to rain storage tank volume. By applying the past weather data, The optimum volume of rain water storage was calculated as 200m$^3$ which mean no benefits according to the increase of storage tank volumes. For optimum planing and control method at the model system, several running method of rainwater storage tank was calculated. The optimum operating method was the using weather data as 3hours weather forecast.

• Resources Recycling
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• v.27 no.2
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• pp.63-67
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• 2018

Gibbs free energy is a measure of relative stability among substances. Since the nature of the ions in aqueous solution is diverse, their thermodynamic data at extensive experimental conditions is scarce. In this work, the calculation procedure was introduced to obtain the absolute and conventional standard molar enthalpies and entropies of hydration of ions from the standard enthalpies and entropies of formation of hydrated ions. The application of correspondence principle to estimate thermodynamic data at high temperature was explained.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.2
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• pp.81-92
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• 2009

This study investigated the occurrence of residues derived animals produced during the process of slaughter and the subsequent channels of processing those residues derived animals; the status of recycling of these residues derived animals by recycling business is investigated to utilize the results as the basic data for management purposes. At present, animal slaughter is highly specialized and the residues derived animals obtained from the slaughter of animals are separated and dissected into different parts to serve as fodder and residual compost. Some of the residues derived animals obtained from slaughter, which are edible are utilized for edible purposes and those parts which are not edible such as horns, claws, fats etc. are confirmed to be recycled. Poultry residues derived animals are mostly recycled as single-component feed, used as original forms, residual compost whereas fish remains are recycled mostly as singlecomponent feed etc. Most of the companies that recycle residues derived animals are situated in provinces such as Jeollanamdo, Jeollabukdo, Gyeongsangnamdo, Gyeongsangbukdo, where many of the slaughterhouses are located. And many of these recylcing business find themselves in the vicinity of these slaughterhouse. Majority of these slaughterhouse are capable of processing residues derived animals in the range of 10~60 ton/day, which is quite small in terms of processing capacity. The problem encountered in the recycling of the residues derived animals is the occurrence of foul smell caused by the decomposition, for which appropriate measures have to be taken. The residues derived animals are on many occasions directly collected and transported to save costs and secure required amount of residues derived animals.

• Resources Recycling
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• v.24 no.3
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• pp.16-26
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• 2015

This study aims to suggest possible policy options for collection of post-consumer diapers as a sustainable prerequisite to implementation of public recycling system with the desktop monitoring results and analysis of collection cost involved. By conducting a diaper collection pilot test on daycare centers and households in the Seoul Nowon-gu, this study revealed that the odor issues did not stand out as an important hindering factor and that the collection rate was the largest contributing factor regarding collection costs. The exploratory cost analysis result shows that the implemented recycling system must guarantee collection rate over 50% via twice-a-week collection frequency, to be comparable or even superior to the current food waste collection cost. Also the pilot demonstration test showed that the final collection rate can be achieved as much as over 50%. The promising data thus obtained cost economically viable future diaper recycling system implementation in the entire Seoul metropolis and adjacent areas of dense population. With the concomitant development of recycling technology and related infrastructure for systematic collection of diaper waste, it makes our society much more sustainable.

• Elastomers and Composites
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• v.47 no.2
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• pp.129-140
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• 2012

The objective of this study was to estimate the practical recycling rate of plastic products, so that the study was conducted to build material flow diagram for PVC profile. For this objective, product generation, waste generation and recycling status were investigated. Using collected and analyzed status data, analysis of material flow by product and building material flow diagram were conducted. As result of estimating the recycling rate by product, The sum of domestic demand was 525,448 ton and waste generation was 105,853ton in PVC flooring and profile. The sum of generation of recycling product and raw material was investigated to be 76,004ton(14.46%), which is higher compared to recycling obligation(8.5%) in 2009. To build the material flow diagram in the years(5~20years) ahead, prediction of future demand was based on the assumption that there will be no difference in annual generation of current and future. As the recycling rate of flooring and profile increases, it is estimated to reach 20% in 2013 according to the material flow diagram.

• Resources Recycling
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• v.26 no.3
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• pp.17-25
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• 2017

Electric arc furnace steelmaking dust has various physicochemical properties as volatile components generated in the melting process of steel scraps in an electric arc furnace, which is captured in oxide form as fine powder by reacting with oxygen in the air. In order to efficiently recycle these electric arc furnace dust, a kinetic basic experiment and a pilot production test were carried out in parallel. As a result, it was found that the electric arc furnace dust contain a large amount of Cl and alkali components, thus it was expected that the compounds have a great adverse effect on the actual operation for the recycling. It was confirmed that the volatilization behavior was progressing actively at $1100^{\circ}C$ and the electric arc furnace dust was melted at $1250^{\circ}C$. These results are the same as a result of pilot test for the formation behavior of zinc oxide and reduced iron. These results should be useful as basic data for designing the recycling plant of the electric arc furnace dust and establishing the operating conditions.

• Resources Recycling
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• v.26 no.5
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• pp.29-38
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• 2017

This study suggests optimal policy options for collection of used diapers through benchmarking of foreign countries and perception surveys. By conducting a survey, this study can identify the actual problems involved in the collection process and enhance the social acceptance toward diaper recycling policies. As a perception survey result, the economic burden of emission bags and sanitary issues were most important for the collection pilot test. Respondents thought that twice-a-week collection frequency was appropriate and that free emission bags might be preferable to participants. Currently municipal wastes are subject to waste management laws, which are applied by local governments. Diaper waste is categorized with municipal waste, so it seems to be treated by municipal waste systems. In terms of connection with government, possible alternatives were suggested to identify the relevant local government. Useful data could be obtained, to determine the economical viability of any future diaper recycling system implementation in the entire Seoul metropolis and adjacent areas of dense population.

• Resources Recycling
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• v.27 no.6
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• pp.76-83
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• 2018

This article aims to summarize the scrap recycling status of gold, silver, platinum and palladium from foreign countries by courntires and industries in order to utilize the data for securing the raw materials of the domestic urbanmining industry. The amount of gold from scrap has shown a tendency to decrease in countries other than China, which is attributed to the large imports of scrap containing gold in China. The industry demand for gold is the highest in electronic products, but demand is decreasing. The amount of scrap recycling in silver has declined in other regions compared to those in Europe, indicating that the world's overall scrap recycling volume has declined. Production and demand from scrap of platinum and palladium are mostly for catalysts and have been steadily increasing until now. However, it is expected that the amount of waste catalysts in automobiles will decrease with the increase of electric vehicle use.