• Journal of Families and Better Life
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• v.16 no.4
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• pp.197-220
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• 1998

This study is conducted to examine the ways to reduce the garbage amount by effective recycling food wastes in the cooking. The data is collected from 864 housewives who live in Seoul/Sungnam/Choongju by using questionnaires from 24 November 1997 to 5 January 1998. The results are as follows; The level of their needs of reusing food wastes in the cooking is high but the level of their participation and its satisfaction to reuse housewives is low. Especially they take part in reusing the garbage in pre-treatment less than edibile plate wastes. These factors result from lacking of their consciousness and knowledge of methods to reuse food wastes. Therefore it is said that consumer should make an effort themselves to participate in reusing food waste researcher should search the way to efficiently reuse the food waste and government should found the policy to provide information and education program for reusing food waste. The more seriously they perceive food waste reuse the mo e they want the way to accelerate food waste reuse by consumer researcher and government.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.5
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• pp.415-420
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• 2013

The new recycling technology for aged Aluminum wires in overhead conductor have been carried out. We are attempting to develop remanufacturing method for them for more effective way of recycling in stead of its conventional remelting process. The weld of aged aluminum wires play a vital role in remanufacture process. The paper investigates the mechanical properties during cold welding process of aged Aluminum wire. The tensile tests and microscopic analysis results are discussed to underscore the hardening features of welded aluminum wire. Various graphs are presented accompanied by discussion about their relevance on the process.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.525-528
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• 2006

Recently, Korea government prepared Act on facilitation of construction waste recycling in December 2003 for effective recycling of rapidly increasing construction wastes, and has enforced the Act on Jan. 2005. This Act limits the definition of recycled aggregates to the aggregates which obtained quality certificate and for this purpose, government has operated quality standard and certificate system of recycling aggregate. The objective of this experimental study is to evaluate the mechanical properties of recycled coarse aggregate concrete according to curing method by ready-mixed concrete. Compressive strength ratio of recycled aggregate concrete under air-dry curing/wet curing was $74{\sim}91%$. KCI code for conventional concrete overestimated elastic modulus for recycled coarse aggregate concrete.

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.38-44
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• 2000

Compared to other waste, waste tire has much discharge quantity and calorie. When we use waste heat from waste tire, it can be definitely better substitute energy than coal and anthracite in high oil price age. To use as a basic data for providing low cost and highly effective heating system, following conclusion was founded. Annual waste tire production was 19,596 million in 1999, Recycling ratio was almost 55% and more than 8.78 million was stored. Waste tire has lower than 1.5% sulfur contain ratio which is resource of an pollution, So it is a waste fuel which can be combustion based on current exhaust standard value without any extra SOx exclusion materials. Waste tire has 9,256Kcal/kg calorific value and it is higher than waste rubber, waste rubber, waste energy as same as B-C oil. When primary and second air quantity was 1.6, 8.0 Nm$^3$/min, dry gas production time was 270min and total combustion time was 360 min. In the SOx, NOx, HC of air pollution material density were lower than exhaust standard value at the back of cyclone and dusty than exhaust standard value without dust collector.

• Journal of information and communication convergence engineering
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• v.15 no.1
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• pp.62-71
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• 2017

This paper presents a low-power voltage converter based on a reconfigurable capacitor array. Its energy recycling capacitor array stores the energy during a charge stage and supplies the voltage during an energy recycle stage even after the power source is disconnected. The converter reconfigures the capacitor array step-wise to boost the lost voltage level during the energy recycle stage. Its energy saving is particularly effective when most of the energy remaining in the charge capacitors is wasted by the leakage current during a longer sleep period. Simulations have been conducted using a voltage source of 500 mV to supply a $V_{DD}$ of around 800 mV to a load circuit consisting of four 32-bit adders in a 65-nm CMOS process. Results demonstrate energy recycling efficiency of 85.86% and overall energy saving of 40.14% compared to a conventional converter, when the load circuit is shortly active followed by a long sleep period.

• Journal of the Korean Electrochemical Society
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• v.4 no.2
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• pp.77-81
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• 2001

Recently, used batteries are causing an environmental contamination and a waste of limited resources with increasing demand of portable secondary batteries in market. In developed countries, their governments have legally required the manufacture to collect and recycle the used batteries, so the related companies have formed an organization for collecting the used batteries and they are effectively recycling them. Unfortunately, an infrastructure for collecting and recycling the used batteries are not established at home yet, while volume of the used batteries are increasing. Therefore, we need an effective measure to ensure the recycling of the used batteries as soon as possible.

• Journal of Environmental Science International
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• v.21 no.10
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• pp.1255-1263
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• 2012

Batch cultivations were performed to evaluate the influences of the initial pH condition on mesophilic and thermophilic acidogenic fermentation with food waste recycling wastewater. In both conditions of mesophilic and thermophilic fermentation, TVFAs production rates were maximized at the initial pH 7 condition as 0.15 and 0.23 g TVFAs/L hr, respectively. And pH was also maintained stably between 6 and 7 during 72hr acidogenic cultivation at both conditions. However, predominant VFA components were different according to reaction temperature conditions. In mesophilic condition, propionic acid which has low conversion efficiency to methane was accumulated up to 1,348 mg/L while acetic and butyric acid were predominant in thermophilic condition. Therefore, thermophilic acidogenic fermentation was superior for the effective VFAs production than mesophilic condition. From the DGGE analysis, the band patterns were different according to the initial pH conditions but the correlations of the each band were increased in similar pH conditions. These results mean that microbial communities were certainly affected by the initial pH condition. Consequently, the adjustment of the initial pH to neutral region and thermophilic operation are needed to enhance acidogenic fermentation of food waste recycling wastewater.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.240-244
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• 2001

Recycling process involving mechanical, thermal, hydrometallurgical, and sol-gel step has been applied to recover cobalt and lithium from spent lithium ion batteries and to synthesize LiCoO$_2$from leach liquor as cathodic active materials. Electrode materials containing lithium and cobalt could be concentrated with 2-step thermal and mechanical treatment. Leaching behaviors of the lithium and cobalt in nitric acid media was investigated in terms of reaction variables. Hydrogen peroxide in 1 M HNO$_3$solution turned out to be an effective reducing agent by enhancing the leaching efficiency. O f many possible processes to produce LiCoO$_2$, the amorphous citrate precursor process (ACP) has been applied to synthesize powders with a large specific surface area and an exact stoichiometry. After leaching used LiCoO$_2$with nitric acid, the molar ratio of Li/Co in the leach liquor was adjusted at 1.1 by adding a fresh LiNO$_3$solution. Then, 1 M citric acid solution at a 100% stoichiometry was also added to prepare a gelatinous precursor. When the precursor was calcined at 95$0^{\circ}C$ for 24 hr, purely crystalline LiCoO$_2$was successfully obtained. The particle size and specific surface area of the resulting crystalline powders were 20 пm and 30 $\textrm{cm}^2$/g, respectively The LiCoO$_2$powder was proved to have good characteristics as cathode active materials in charge/discharge capacity and cyclic performance.

• Resources Recycling
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• v.18 no.3
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• pp.11-19
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• 2009

Recently the problem of global environment is became by social issue. Accordingly the interests to recycling and saving of resources are growing from daily life to varieties field of industry. To preserve the global environment, prevent global warming, environmental destruction, environmental pollution by wastes, the drain of aggregate, plasticity energy of cement and decrease in carbon dioxide are an urgent problem that must be resolved. So there is to a field of building industry and stands but on the inside of the building the many double meaning resources usefully, applies. Also the seller masterpiece building where the service life is long planned is safe and comfortably, maintenance, suppresses the construction which is not necessary is unnecessary. Also the seller masterpiece building where the service life is long planned is safe and comfortably, maintenance, suppresses the construction which is not necessary is unnecessary. By revitalizing effective use of limited earth resources, recycling and controling production of construction waste, this study introduced to a method for Long-Term Durability of Construction Structure and Effective Use of Technology for Construction Waste considering architectural demand and earth environment. It is for reduction of an earth environment load from the side of construction production and performance design of a structure.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.52-58
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• 2015

White ledger usually includes white office paper, computer paper, and copy machine paper. Because these grades need high optical properties, fluorescent whitening agents (FWAs) are widely used in the papermaking process. FWAs are the most powerful and effective chemical used to obtain high CIE whiteness and ISO brightness in papers. The rising demand for white or ultra-white papers has increased the use of FWAs. However, FWAs used in white ledger can restrict its use, even though white ledger is widely used as a raw material in paperboard mills. Therefore, it is necessary to develop methods to control FWAs from white ledger to increase its use in paperboard mills. In this study, the behaviors of disulpho fluorescent whitening agent (D-FWA), tetrasulpo fluorescent whitening agent (T-FWA), and hexasulpho fluorescent whitening agent (H-FWA) during the recycling process were identified as a first step to remove FWAs from white ledger. We prepared four types of papers (dyed with D-FWA, T-FWA, and H-FWA), disintegrated these papers, and made handsheets. This recycling process was carried out three times in a laboratory. After each round of recycling, the hand-sheets' CIE whiteness and fluorescence index were measured, and the distribution of FWAs in the Z-direction was observed using CLSM images. FWA reductions in the model papers were calculated using fluorescence indices as a function of the number of recycling. FWAs in handsheets containing T-FWA and H-FWA decreased linearly as a function of the number of recycling, but D-FWA did not show a significant reduction in the fluorescence index after recycling. T-FWA and H-FWA showed similar distributions of D-FWA after recycling. Therefore, as much T-FWA and H-FWA as possible must be detached in the early processes of papermaking at paperboard mills.