• 한국환경과학회지
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• 제16권9호
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• pp.1085-1090
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• 2007

The performance of EF (electroflotation) on the thickening of activated sludge were investigated using laboratory scale batch flotation reactor. In this paper, the effects of parameters such as electrode material, NaCl dosage, initial sludge concentration and electrode distance were examined. The results showed that the performance for sludge thickening of the five electrodes lay in: Pt/Ti > Ru/Ti > Ir/Ti > Ti mesh > Ti plate. The more NaCl dosage was high, the more sludge was thickened and the shorter thickening time was obtained. However, considering the final thickening time and sludge concentration, optimum NaCl dosage was 0.5 g/L. Thickening time and sludge concentration was not affected by electrode distance. In DAF (dissolved air flotation) system, optimum recycle ratio was 40% and thickening performance was lower than that of the EF.

• 한국양봉학회지
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• 제34권4호
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• pp.315-323
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• 2019

Large amounts of sludge produced by paper mill industries represent one of the most serious environmental problems in the world. Recently, beekeepers living in the neighborhood of the paper mill in Hwasan County, Youngcheon city, GB, Korea, became alarmed that honey bee colonies were dying off suddenly across the neighborhood. A preliminary study was conducted to evaluate the toxicity (oral, fumigation, repellent) of recycled solid paper mill sludge (SPMS) and leachate paper mill sludge (LPMS) to honey bee workers under laboratory conditions, and to analyze the volatile organic compounds(VOC). The SPMS and LPMS were separately subjected to a liquid-liquid extraction (LLE) at three temperatures to extract VOC(highest VOC yields: 1.52% SPMS and 0.34% LPMS). A total of 70 chemicals were detected in the VOC of paper mill sludges, of which 49 and 21 volatile organic compounds from SPMS and LPMS, respectively. The SPMS was dominated by high degree presence of stanols (saturated sterols), such as cholestanol, cholestan-3-ol and also saturated hydrocarbons. However, LPMS was characterized by the absence of sterols. Both SPMS and LPMS showed an influence on the olfactory behavior of honey bee on Y-tube assay, with repulsion rates of 72 and 68%, respectively. Both SPMS and LPMS at concentration of 100mg/mL caused higher honey bee oral mortality than the untreated controls at 48, 72, 96 and 120 hours after treatment(highest oral mortality at 120 hr: 85.74%(SPMS); 93.51 % (LPMS)). A similar pattern was observed when honey bees were tested to fumigant toxicity. Both SPMS and LPMS caused significant higher mortality than the untreated control 24 hour after the exposure (highest fumigation mortality at 120 hr: 69.4% (SPMS); 56.8% (LPMS)). These preliminary results indicated that paper mill sludge could be partly responsible for sudden death and disappearance of honey bees, especially in hot humid summer days. With climate change, the risk of environmental chemical exposure to honey bee would pose greater attention.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.333-338
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• 2000

The purpose of this study is to evaluate the compressive strength properties of municipal waste ash hardening using the unrefined fly-ash and paper sludge ash and to offer basic data to someone for recycling municipal waste ash. Unrefined fly-ash and paper sludge ash are used with admixture. MWA are tested that grading, specific gravity and pH value and observed microsructure of particle with SEM. The compressive strengths of MWA hardening which is mixed with regular ratio according to each admixture are measured. In the results of test, fly-ash is very effective for reducing content of cement by 50% in the recycling of MWA. But proper content mixed paper sludge ash is recommend by about 20% in binder.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.40-47
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• 2005

Modeling and simulation for simultaneous saccharification and fermentation (SSF) process in bioconversion of paper mill sludge to lactic acid was carried out. The SSF process combined the enzymatic hydrolysis of paper mill sludge into glucose and the fermentation of glucose into lactic acid in one reactor. A mathematical modeling for cellulose hydrolysis was developed, based on the proposed mechanism of cellulase adsorption deactivation. Another model for simple lactic acid fermentation was also made. A whole mathematical model for SSF was developed by combining the above two models for cellulose hydrolysis and lactic acid fermentation. The characteristics of the SSF process were investigated using the mathematical model.

• 펄프종이기술
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• 제42권2호
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• pp.12-19
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• 2010

This study was carried out to explore the availability of seedling pots made from paper mill sludge using red pepper species called Nokkwang. The seedling pots were made by several conditions such as different mixing ratios between sludge and old newspaper (ONP), sterilizing treatment and latex coating. After 30 day cultivation in a green house, the growth condition of the red peppers was evaluated by comparison with those raised in the plastics seedling pots. The red peppers in the plastics pot showed a better growth than those in the sludge pots. Sterilizing treatment, latex coating and different mixing ratios between paper sludges and ONP did rarely affect a growth rate of the plant and the contents of inorganic elements. However, latex coating contributed to protection of physical structure of the sludge pots in spite of constant water feeding. Even though some inorganic elements from the sludge pots migrated into the bed soils, electronic conductivity of the bed soils was within the proper range for the plant growth. Finally it was confirmed that the seedling pots made from paper mill sludges could be used to cultivate horticultural plants as the alternative to the plastics pots.

• 펄프종이기술
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• 제35권1호
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• pp.27-32
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• 2003

To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.

• 한국습지학회지
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• 제15권4호
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• pp.471-476
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• 2013

위생용지 제조 폐수처리장에서 발생하는 슬러지를 3년간의 일일 운전일지를 토대로 분석하였다. 발생 폐기물은 79% 슬러지, 14% 재, 5%의 합성폐기물 및 기타 2%로 구성되었다. 일일 최대 슬러지 생산량은 233톤, 평균 슬러지 생산량은 113톤으로 분석되었는데, 일차 슬러지가 85% 및 이차슬러지는 15%를 차지하였다. 슬러지 탈수용 응집제의 농도는 과량 주입되고 있어 적정 응집제 주입을 위해 주기적으로 쟈테스트와 같은 부가적인 실험에 의한 주입농도의 설정이 필요한 것으로 나타났다. 현재 발생되는 폐슬러지의 일부는 위탁처리되고 있고, 일부는 자체 처리되고 있지만, 장기적으로는 대부분의 폐슬러지가 제철소 슬러거의 진정재로 재활용될 계획이다.

• 한국자동차공학회논문집
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• 제12권6호
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• pp.151-157
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• 2004

In this paper deals with behavior of the magnetic abrasive using sludge on polishing characteristics in a new internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. The magnetic abrasive using sludge-abrasive grain WA and GC used to resin bond fabricated low temperature. And sludge of magnetic abrasive powder fabricated that sludge was crused into 200 mesh. The previous research have made an experiment in the static state the movement of magnetic abrasive grain is nevertheless in the dynamic state. In this paper, We could have investigated into the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.165-166
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• 2018

Researches for the development of renewable energy as a fuel substitute for global warming and depletion of petroleum resources are actively being carried out. Among them, the annual growth rate of PV generation is 20.73%, which is higher than other renewable energy sources. However, the production of 1 ton of polysilicon, which is known as a raw material for solar power generation panels, generates 2 tons of waste. As the demand for PV panels increases, the problem of the treatment of polysilicon sludge is attracting attention, and studies on the utilization of polysilicon sludge are needed. Therefore, in this study, the applicability of polysilicon sludge treated as industrial waste to the lightweight panel for architectural purposes was examined.

• 유기물자원화
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• 제14권3호
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• pp.101-109
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• 2006

쌍용 P&G 제지공장 및 유한킴벌리 제지공장에서 발생한 제지슬러지 또는 우분을 줄지렁이의 먹이로 공급하면서 줄지렁이의 섭식량, 증체율 및 먹이에 대한 배설률을 조사하였다. 제지슬러지를 먹이로 공급하였을 경우에는 줄지렁이의 생체량이 증가하였으나, 우분을 먹이로 공급하였을 때는 먹이급이 70일 후에 지렁이 개체군이 사멸하였다. 섭식한 먹이의 지렁이 생체로의 전환률은 먹이급이 84일후에 건중량 기준으로 성충, 노령 유충 및 유령 유충 순으로 P&G 제지슬러지의 경우 0.48, 0.40, 0.76%로 유령유충이 입식된 사육상에서 높았고, 유한킴벌리 제지슬러지의 경우 0.26, 0.45, 0.42%로 성충이 입식된 사육상에서 가장 낮았다. 섭식한 먹이에 대한 지렁이의 배설률은 성충, 노령 유충 및 유령 유충 순으로 P&G 제지슬러지의 경우 49.02, 54.32, 55.39%이었고, 유한킴벌리 제지슬러지의 경우 32.22, 41.86, 40.69%로 P&G 제지슬러지에 대한 배설률이 유한 킴벌리에 대한 배설률보다 높았다. 우분에 대한 배설률은 성충, 노령 유충 및 유령 유충 각각 73.73, 57.89, 76.38%로 제지슬러지보다는 높은 배설률을 나타내었다.