• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.53-61
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• 2018

Anaerobic digestion (AD) is one of the most widely used process that can convert the organic fraction of waste activated sludge (WAS) into biogas. However, most researched actual methane yields of anaerobic digester (AD) on lab scale is lower than theoretical ones. Bioelectrochemical, anaerobic digester was used to increase methane yield from waste activated sludge. The influence of anaerobic digestion sludge and raw sludge mixing ratio (3:7, 5:5) on methane yield and organic matter removal efficiency were explored. As a result, when the mixing ratio of bioelectrochemical anaerobic sludge was 5:5 compared with 3:7, the highest methane yields were 294.2 mL $CH_4/L$ (0.63 times increase) and 52.5% (7.5% increase), the bioelectrochemical anaerobic digester(5:5) was more stable in the pH, t otal alkalinity and VFAs, respectively. These results showed that the increase in the mixing ratio of anaerobic digestion sludge was found to be effective for maintaining the stable performance of bioelectrochemical anaerobic digester.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.160-161
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• 2015

This research reviewed the characteristics of waste concrete sludge occurred from recycled aggregate producing process and the physical and mechanical properties of the mortar incorporated the pulverized the waste concrete sludge. From the results of the experiment, as the replacement ratio of waste concrete sludge powder was increased, the dosage of superplasticizer to satisfy the target flow of 200 ± 10 was increased, and the compressive and flexural strengths were decreased. On the other hand, when the sludge powder replacement ratio was 25 %, outstanding performance of general characteristics of mortar was obtained while it was lower than Plain mixture, thus, further detail study on various replacement ratios of waste concrete sludge powder is needed.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.308-313
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• 2005

실리콘 잉고트의 절단공정에서 발생하는 폐실리콘 슬러지는 실리콘과 실리콘카바이드 등의 유가자원이 함유되어 있으며, 이 중 실리콘 분말은 실리콘 화합물인 알콕시실란 등을 제조하는데 원료로 사용이 가능하다. 본 연구에서는 폐실리콘 슬러지로부터 분리, 합성된 사에 톡시실란(TEOS)을 원료로 이용하여 실리카 나노분말을 합성하였다. TEOS 원료물질을 외부 혼합형 이류체 노즐을 이용하여 미세액적으로 분무하고 화염 속으로 도입시키고 화염열분해 반응을 진행시켜 실리카 나노분말을 합성하였다. 합성된 실리카 나노입자의 특성은 투과형 전자현미경 및 BET에 의하여 입자형상 및 평균 입자크기가 분석되었다. 주요 공정변수인 분산공기의 압력, 반응가스의 조성을 변화시켜 실험한 결과 평균크기가 $9{\sim}68nm$인 실리카 나노분말을 제조하였다.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.49-49
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• 2002

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.215.1-215
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• 2003

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05a
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• pp.183-186
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• 2001

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.58-65
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• 2001

To produce the substitute for farmland were mixed concrete waste and organic wastes. To estirnate the application of the mixture for farmland components in the solid and the leachate from the mixture were analyzed according to the ordinance of the Waste Society in Germany. Plants were cultivated in the mixture and its harvests were measured. The results showed that the mixture from waste may be used for the reclamation of landfill and landscaping according to circumstances, and the best mixture was from 85% of concrete waste, 10% of sewage sludge and 5% of paper mill sludge.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.310-311
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• 2003

본 연구에서는 폐수산자원인 불가사리와 조개껍질 분말을 이용한 탈수보조제(물리개량제)의 가능성을 확인하였다. 불가사리와 조개껍질을 이용한 탈수보조제는 유가자원 소모라는 기존의 탈수보조제의 문제점을 보완하여 폐자원의 자원화라는 이점이 있으며 탈수케이크의 함수율을 효과적으로 낮추어 주어 소각등의 후속공정에 도움을 줄 수 있는 것으로 사료된다. 뿐만아니라 천연 비료로 사용되어지는 불가사리의 활용이라는 점에서 탈수슬러지 퇴비화등 자원 재이용에의 적용성 또한 증대시킬 수 있다.

• Resources Recycling
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• v.16 no.5
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• pp.41-45
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• 2007

Tetramethylorthosilicate (TMOS) and silica nanopowder were synthesized from the waste silicon sludge containing 15% weight of silicon powder. TMOS, a precursor of silica nanopowder, was firstly prepared from the waste silicon sludge by catalytic chemical reaction. The maximum recovery of the TMOS was 100% after 5 hrs regardless of reaction temperature above $130^{\circ}C$. But the initial reaction rate became faster while the reaction temperature was higher than $150^{\circ}C$. As the methanol feedrate Increased from 0.8 ml/min to 1.4 ml/min, the yield of reaction was not varied after 3 hrs. Then, silica nanopowder was synthesized from the synthesized TMOS by flame spray pyrolysis. The morphology of as-prepared silica nanopowder was spherical and non-aggregated. The average particle diameters ranged from 9 nm to 30 nm and were in proportional to the precursor feed rate, and precursor concentration.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.353-358
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• 2009

The ability of natural abrasives which were recovered from CRT glass polishing process was evaluated. Comparing the center line average roughness values of a glass polished with new pumice (Ra = $0.039{\mu}m$) and with new garnet (Ra = $0.031{\mu}m$), the glass surface polished with the recycled pumice and the garnet had less pits on the surface with smaller Ra values (Ra = $0.025{\mu}m$ for recycled pumice and Ra = 0.029 for recycled garnet). Recycled rouge contains amorphous glass fragments so that it should be used as a cement replacement rather than recycle into an abrasive. Nnatural abrasives, pumice and garnet powder, which are used in CRT glass polishing process can be recycled into abrasives so that it can help to minimize costs and environmental impact from the production of abrasives and the disposal of waste sludge.