• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.1
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• pp.39-45
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• 2008

As a waste management tool, the prohibition of landfilling of food waste has enforced since 2005. the composition of municipal solid waste (MSW) has changed dramatically. In this study, MSW generated from a small city collected once a year in 2004, 2005 and 2007, to qualify the characteristics of MSW before and after implementation of the tool. The prohibition of landfilling of food waste dramatically reduces food waste in MSW to 5.5 weight %, and on the other hand results to increase papers to 50.6 % and plastics to 22.6 %, The bulk density lowers to 50 %, which newly propose the necessity of volume reduction and incineration of MSW to ensure efficient transport and disposal. As water content of MSW reduces to 15.9 %, lower heat value of MSW after prohibition of landfilling of food waste increase to 3565.6 kcal/kg. Mitigation of bad smell and waste leachate with lower contaminants are recommendable as a kind of positive effects benefited by the tool.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.80-86
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• 2007

In this study we experimented setting time and basic properties as waste wood fiber and sodium silicate substitution rate to reuse waste wood fiber produced in construction field to wood chip board. To do this construction waste woods were crushed with the size less than 10mm, mixed with the rate of 1:2, 2.5, 3, and added sodium silicate with the rate of 0, 5% of cement content. The results are as follows. As the substitution rate of construction waste wood was increased delay of setting time was also increased, and the batch of adding 5% accelerator had a 13~17 hours faster setting time than non accelerator batch. The compressive strength was lower as wood substitution rate was higher, and as the specific gravity was higher, the strength was also higher. As wood substitution rate was higher, heat conductivity was lower, and as specific gravity was higher, heat conductivity also was higher.

• Journal of Environmental Science International
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• v.12 no.9
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• pp.911-919
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• 2003

When the city water was heated for the optimum use of unused energy, the energy flows and losses were calculated and evaluated to improve the value of heated water systems at dwelling side. To obtain this purpose, it was simulated on heat flows under two conditions like with heat pumps or not and calculated the energy sayings. Furthermore, recycling water system was suggested for enhancing the value of heated water system. From this results, the energy flows without heat pumps showed that it was 3-4 percents of heat losses from pipes, 62 percents of energy savings from hot water uses and 34 percents of unutilized heat. When the heated water system adopt the recycling water system at dwelling side, it was improved 12 percents of total energy sayings.

• Resources Recycling
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• v.18 no.2
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• pp.69-76
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• 2009

Alumina powder was prepared from heat-treatment of artificial marble waste fine aggregate containing $Al(OH)_3$ for the purpose of the feasibility of its recycling. Artificial marble waste was heat-treated between $500^{\circ}C$ and $1000^{\circ}C$ and XRD, BET surface area, BJH pore size distribution and adsorption of As were analyzed for heat-treated powder. It was found that the adsorption efficiency of As was significantly affected by phase composition of alumina powder rather than its physical characteristic. Heat-treated powder compact was sintered to produce the pellet. Alumina pellet with porosity more than 60% could be obtained after sintering below $1200^{\circ}C$ and also the addition of glass powder as a sintering aid had a positive effect on lowering sintering temperature, led to the high porosity near 60% and adsorption of As over 60% even at $900^{\circ}C$.

• Resources Recycling
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• v.4 no.4
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• pp.70-75
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• 1995

Waste tires arc used as landifill, combustion and recycling. Rccenllg. lhc recycling of waste tires received a great attentmu fiam all industries. Thc rccgcling methods for w s l e tires are classified inla three culegoljz, a whole tirc, cmmb rubha and energy. T h ~ ssl iidy invesligvled the pruduclion ol Lhc ruhhcr block by using clumh cubbel oI wasle Ires. The process 01 manulacluring the ~uhher block was co~lsislerl ol several slepc: collecting lilts, ctuilnng and grinding hrcs, mixing crumh ruhher wlth bmder. and shaping under heat and pressure The effccl ol binder on ll~e ~uecl~ilnicaplr opcrlics o l r uhher hlock war also investigalcd. The economic feaqihility of a surface treiilmcnl and multilayas on the rubber block was dclcimincd

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.20-27
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• 2019

Compared to the development and manufacturing technology of electronic goods, the development of waste glass recycling technology is relatively insufficient, leading to the acceleration of waste of resources and environmental pollution. Although waste glass recycling technology is being actively developed overseas, waste glass recycling technology is insufficient in Korea, leading to the illegal dumping or burial of waste glass. Waste glass has been confirmed to have pozzolan reaction potential when having hydration reaction with cement. Waste glass is also reported to be effective in reducing bleeding and inhibiting the development of hydration heat by improving the physical properties of concrete and the rheology properties of fresh concrete. Therefore, this paper analyzed the strength characteristics and the effect of alkalic-silica reaction on the expansion of shielding concrete that used waste glass as fine aggregate. Where, suitable admixture materials were used as a measure to suppress the expansion.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.317-322
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• 2005

Nowadays, recycling of aggregates from the waste concrete is in big demand due to the protection of environment and the shortage of aggregates that are needed for ever expanding construction projects. This study was undertaken to examine the feasibility of recycling waste concrete powder produced in the crushing process of demolished concrete as a filler material for polymer mortar. In this study, polymer mortar specimens were prepared by varying the mix proportion of polymer binder (ranging 9~15 wt%), waste concrete powder (ranging 0~20 wt%) substituted for silica powder, 0.1~0.3 mm fine aggregate (ranging 21~24 wt%) and 0.7~1.2 mm fine aggregate (ranging 44~47 wt%). For the prepared polymer mortar specimens, various physical properties such as strength, water absorption, heat water resistance, acid resistance, pore distribution and SEM observation were investigated in this work. As a result, physical properties of polymer mortar were observed to have remarkably improved with an increase of polymer binder, but greatly deteriorated with an increase of substitution quantity of waste concrete powder.

• Resources Recycling
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• v.18 no.2
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• pp.3-15
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• 2009

To accomplish the greenhouse gas reduction which is over core unit project of the "Green growth" policy and "Resource circulation society", it is important to maintain proper balance and complement between energy recovery from waste and material recycling. This research(study) examined the related policies on the past of korea and foreign country, and also "The 4th resource recycling master plan" and "Energy recovery from waste plan" to provide advisable direction for resource recycling policy. The results of the research(study) showed that there were no significant difference between korea and developed foreign countries waste management policies. But in German policy, energy recovery from waste and pre-treatment are importantly considered and highly required for permission. Under current circumstance in korea, recycling will be more difficult than in the past. According to "The 4th resource recycling master plan", film type of synthetic resin was not sustainable recycled material in substance."Energy recovery from waste plan", proved that the energy recovery from RDF/RPF have lower efficiency than regular incineration generation and substance recycling. To solve these problems, the energy and remainder heat recovery must be generalized to "Energy recovery" concept and institutional improvement such as LCA(Life Cycle Assessment) system are need to support it. And also technology development to extract synthetic polymer by dissolved film type of synthetic resin must be provided.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.456-459
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• 2008

The 10t/d pyrolysis demonstration plant for waste tire recycling have been constructed and operated for commissioning of the plant. The plant have the tube reactor with chain conveyer attached disk. The reactor temperature is 500$\sim$600deg.C and pressure is -80$\sim$-100mmHg. Non-condensable gas is used as fuel for pyrolysis heat source.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.4
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• pp.38-44
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• 2010

Foundry sands are made up of silica and some coking agents, such as bentonite or resin, and used as templates for the production of various casting products. Foundry sands, which are repeatedly used, were finally transformed into the waste materials by heat, losing their proper functions. The used foundry sands have been treated as general wastes according to the contents of coking agents used. Silica, however, can be recycled through the proper treatment due to its physical property not to changed by heat. In this study, we have identified and investigated at the occurrence, treatment and recycling status of the used foundry sands, as well as for the regime and inhibitory factors of the recycling of them in domestic and foreign cases.