• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.660-667
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• 2020

This study focused on the epoxy resin production process, which uses the steam of 155 ℃ or higher as a heat source, and discards all condensate generated. A part of the process is operated at low temperatures of 70 ℃ or below, thus there are opportunities to reduce the steam consumption by recycling wasted condensate as a heat source for the low temperature section of process. In this study, we developed process models that can reduce steam by recovering waste heat through recycling condensate and conducted a case study to find an optimal condensate recycling system. Three different process designs were proposed and economic evaluations were performed by comparing annual capital costs and steam savings in each case. Finally, an annual steam consumption of the low-temperature section could be reduced by up to 67.6%, which could also bring an additional economic benefit of 522.1 million won/yr.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.115-118
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• 2001

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.614-619
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• 2010

We proposed perfect recycling method of sea waste. The sea waste(rotten sea fish, rotten shell fish etc.) have bad smell and generate waste water, so these waste materials must be treated quickly. If we use speedy dryer, these sea waste can be changed to useful feed and liquid composts. Also this study relates to a method for drying a variety of untreated waste materials in a hermetically sealed state, and subsequently carbonizing the dried waste materials under a reduced pressure, thereby achieving a more stable and economical treatment for the waste materials, and an apparatus for performing the method. This effects of preventing generation of contaminants and environmental pollution while reducing fuel costs, and a carbide, obtained via the drying and carbonization of the waste material, are available into feed for poultry. The condensate water can be used to deodorants.

• Fashion & Textile Research Journal
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• v.25 no.6
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• pp.673-689
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• 2023

To realize the traceability of sustainable textile products, this study presents a low-carbon process through energy savings in the textile material manufacturing process. Traceability is becoming an important element of Life Cycle Assessment (LCA), which confirms the eco-friendliness of textile products as well as supply chain information. Textile products with complex manufacturing processes require traceability of each step of the process to calculate carbon emissions and power usage. Additionally, an understanding of the characteristics of the product planning-manufacturing-distribution process and an overall understanding of carbon emissions sources are required. Energy use in the textile material manufacturing stage produces the largest amount of carbon dioxide, and the amount of carbon emitted from processes such as dyeing, weaving and knitting can be calculated. Energy saving methods include efficiency improvement and energy recycling, and carbon dioxide emissions can be reduced through waste heat recovery, sensor-based smart systems, and replacement of old facilities. In the dyeing process, which uses a considerable amount of heat energy, LNG, steam can be saved by using "heat exchangers," "condensate management traps," and "tenter exhaust fan controllers." In weaving and knitting processes, which use a considerable amount of electrical energy, about 10- 20% of energy can be saved by using old compressors and motors.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.2
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• pp.41-48
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• 2020

In this study, organic carbon was extracted from the condensed water of food waste drying process to estimate the applicability as external organic carbon sources. The COD, TN, TP and TS of condensed water were 21,374 mg/L, 148 mg/L, 4.19 mg/L, and 455.7 mg/L, respectively. In addition, the content of biodegradable organics in condensed water was 47%. The fractional distillation and the vacuum evaporation were employed for extracting organic carbon. There were 8 extraction conditions, but 4 conditions were available for extraction. They were 1) 0mmHg, 110℃ 2) -600mmHg, 70℃ 3) -500mmHg, 80℃ 4) -600mmHg, 80℃. All 4 conditions showed the highest organic concentration and the highest quantity of organics when extracted 10% of initial volume. It was estimated that optimum conditions were 80℃, -600mmHg and 10% extraction. Then, extraction concentration, extraction quantity, extraction efficiency, extraction time, BOD/TCOD ratio, TVFAs/TCOD ratio and NH₃-N were 174,200 mg/L, 8,710 mg, 46%, 10 min, 0.97, 0.74 and 75.5 mg/L respectively. Therefore, the extracted organic carbon can be utilized as external organic carbon sources.

• Resources Recycling
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• v.27 no.3
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• pp.30-38
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• 2018

In this study, the behaviors of Fe selective chlorination in ilmenite ore by using PVC or $CO-Cl_2$ gas mixture as reducing agents under the condition of 1173 K, for 60 minutes were investigated. The weight loss ratio was 28% when PVC was applied as the reducing agent. The condensate formed at the outlet of reaction tube was identified as $FeCl_2$ by X-ray diffraction analysis. From these results, it was observed that iron in ilmenite ore reacted with HCl gas and Fe was selectively removed in the form $FeCl_2$. However, when $CO-Cl_2$ gas mixture was used as a reducing agent, the weight reduction ratio was 54%, and the condensate formed at the outlet of reaction tube after the experiment was estimated to be $FeCl_3$. It was observed that the ilmenite ore reacted with the $CO-Cl_2$ gas mixture and was simultaneously removed in the form of $FeCl_3$ and $TiCl_4$. However, the results of X-ray diffraction of ilmenite ore after the reaction showed that Fe was almost removed.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.15-25
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• 2022

In this study, the efficiency of treatment of moisture and organic matter in food waste was analyzed according to the air blast volume and preheating using the bio-drying method. Te mount of air blast volume and preheating were determined by the evaluation of temperature and CO2 during food waste treatment using the bio-drying method. As a results, the increase in the air blast volume increased the moisture removal efficiency and removal rate, but, lowered the temperature inside the bio-drying by the decease in microbial activity. In order to maintain the activity of microorganisms, it was estimated that it was necessary to inject an appropriate air blast rate according th the properties of the food waste. In this study, the injection of air blast volume at 15L/min was optimal. It was evaluated that the organic matter and water removal rates according to the presence or absence of air preheating, the organic matter removal rate and water removal rate increased by 3-5% when air preheating was not performed. Also, there was no internal aggregation caused by the generation of condensate inside the bio-drying. Therefore, for effective bio-drying of food waste, it is necessary to maintain an appropriate air blast volume to maintain microbial activity, and it is considered that injection through preheating of air is required.