• 펄프종이기술
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• 제47권4호
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• pp.66-75
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• 2015

Disposable diaper waste is consisted of plastic, fiber, and SAP (Super Absorbent Polymer). They are valuable to be used as raw materials of other products including plastic blocks and pulp mold. Nevertheless, disposable diaper waste have been disposed by landfill and incineration without recycling. Due to strict environmental regulations it is necessary to develop fractionation technique to recycle the disposable diaper waste. In this study the fractionation technique using pilot-scale stock preparation units was investigated. Process for separation of plastic and fibers from disposable diaper waste was composed by the combination of pilot-scale pulper, drum screen, screen and cleaner. Recovery rate of plastics and fiber was checked according to the various operating conditions. In drum screen, recovery rate of plastic was high when the cut size of disposable diaper waste was $5cm{\times}5cm$. The highest recovery rate of fiber was achieved with 0.3 mm slot screen. It is important to control the neutral state of SAP for improvement of recovery rate of fiber since SAP can be swelled easily in water. Therefore SAP can be controlled efficiently by the addition of calcium chloride into the pulper. Consequently recovery rates of plastics and fibers were over 90 and 80% under the optimum pilot operating conditions.

• Membrane and Water Treatment
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• 제2권3호
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• pp.175-185
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• 2011

Ultrafiltration is an emerging technology for drinking water treatment because it produces better water quality as compared with conventional treatment systems. More recently, the combination of UF technology with other processes in order to improve its performance has been observed. These associations aim to maximize the contaminants removal and reduce membrane fouling. The operational performance of contaminants removal and water production of two UF pilot plants was compared. The first plant (Guarapiranga) was fed with raw water and the second plant (ABV) with pre-treated water by the coagulation, flocculation and sedimentation processes at Alto da Boa Vista WTP (Sao Paulo, Brazil). Both units operated continuously for approximately 2,500 hours, from September/2009 to January/2010. The results showed that the ABV UF pilot plant was able to operate at higher specific fluxes (6.2 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$) than Guarapiranga (3.1 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$). However, the number of chemical cleanings conducted in both pilot units during the considered operation period was the same (4 chemical cleanings for each plant), which shows that the pre-treatment reduced the membrane fouling. The water quality at ABV for all the variables analyzed was better, but the feed water quality was also better due to pretreatment. The rejection values for the different contaminants were higher at Guarapiranga mainly because of a pollution load reduction after pre-treatment at ABV. Even with the better performance of the ABV UF pilot plant, it is necessary to take into consideration the complexity of the complete treatment system, and also the costs involved in the construction and operation of a full-scale treatment unit.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.221-222
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• 2003

Typically, closed production system units are subject to an accumulation of fine suspended solids and dissolved organics (Weeks et at., 1992). Foam fractionation process is believed to be most effective in marine application for solids removal. In present experiment, the performance of foam fractionator for removal of solids, protein, and other dissolved materials was evaluated at different foam overflow heights and air flow rates in a pilot-scale recirculating aquaculture system for culture of Korean rockfish. (omitted)

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2002년도 추계총회 및 연구발표회 초록집
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• pp.124.2-124
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• 2002

• Applied Biological Chemistry
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• 제27권
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• pp.3-17
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• 1984

Anaerobic digestion has recently attracted all over the world and Korea also shows no exception. The major benefits of anaerobic digestion are energy production, water pollution control, pathogen reduction and effective manure production. In Korea it was recognized in late sixties that there was a positive need to find alternative energy for farmers household. The main traditional energy sources in rural area were crop residues and forestry products. Therefore Office of Rural Development through its Rural Guidance Bureau disseminated about 29,000 household biogas units from 1969 to 1975 to provide cooking fuel for farmers household and to improve the mode of farmers living standards. The units were welcomed by farmers at that time. Now, however, most of them are not using due to a number of reasons associated with cold winter and some techno-economical problems (in those day, fossil fuel was quite expensive to compare with other prices and since then farmers income was quickly increased). The author studied on bag type household biogas plant to solve some technical problems of existing household biogas plants, but this also has little appeal for the farmers. From 1977 author studied on village scale biogas plant with two pilot plants. From the viewpoint of energy production, COD removal, kill rate of pathogen and fertilizer value, the results obtained from the experiments were quite promising, but the construction cost of the village scale biogas plant was too high for the farmers in Korea. To find most suitable biogas plant for farmers in Korea through the simplifying the biogas digester, the author developed batch-load biogas plant. By feeding coarse crop residues and manures, total solids concentrations of the batch-load biogas plant are about 28 percent which is much higher than continous digester of 5-8 percent. The batch-load biogas plant was welcomed by many farmers in Korea when it was reported on TV and newspapers. The plant was disseminated 154 units in 1982, 766 units in 1983 and 812 units in 1984 as a promissing project. Besides these biogas plant experiments, studies were also conducted 1) to determine gas production rate with agricultural wastes, 2) to evaluate the effect of loading rate, dilution, retention time on biogas production, 3) to project the amount of potencial energy from agricultural wastes.

• 한국대기환경학회지
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• 제10권1호
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• pp.49-56
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• 1994

Electrostatic Precipitators( EP ) are widely used in industry for controlling the emission of particulate pollutant Recently, a number of researches have been conducted to solve performance and reliability problems of EP, As a result of researches in the laboratory and of pilot scale, a technology of wide-pitch-spacing has been successfully applied to full scale units. It has been known that the wide-pitch-spacing can reduce the capital cost of newly installed precipitators, and the cost of rebuilding existing uints. In this paper, a systematic study was performed to develop a wide-pitch electrostatic precipitator. The study includes experimental and numerical work on the following : Particle collection characteristics for a bench-scale unit; gas flow characteristics( temperature and velocity distributions): other EP operating variables such as electric Power supply/control. The results are applied directly to design of wide-pitch-spacing EP and the developed numerical model was found to be a good argreement with the experimental results. The EHD simulation program is necessary to design the high efficiency EP.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1995년도 제2회 KOSCI Workshop
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• pp.91-103
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• 1995

In recent years, significant advances have been made in the development of methods to predict ash behavior in utility boilers. This paper provides an overview of methods used to assess and predict ash formation and deposition. It has discussed some of the key problems associated with the formation and deposition of ash during the combustion of pulverized coal. Although considerable progress has been made in understanding of the fundamental mechanisms of ash formation, transport, growth, and strength development, there is still much work to be done. There is a need to develop quantitative relationships between the characteristics of the entrained ash and the physical properties of ash deposits that influence deposit growth, strength development, and cleanability. Also data from bench-scale, pilot-scale, and full-scale units are needed in order to determine operating conditions which will minimize deposition problems, maximize efficiency, and reduce emissions.

• 신재생에너지
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• 제2권2호
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• pp.118-125
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• 2006

The target of this work was the process development of demonstration plant to produce the high quality alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70 t/y and the pilot plant of 360 t/y had been developed. Main research contents in this step were the process performance test of pilot plant of 360 ton/year and the development of demonstration plant of 3,000 t/y, which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/y showed about 80% yield of liquid product, which was obtained by both light gas oil(LGO) and heavy gas oil(HGO), The boiling point range distribution of LO product that was mainly consisting of olefin components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

• 한국습지학회지
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• 제9권1호
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• pp.69-78
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• 2007

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of $5{\times}5{\times}0.65m$ (width ${\times}$ length ${\times}$ media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/$m^2.yr$ and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 - 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of $4.5{\times}4.5m$ ($width{\times}length$). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The $5,200-m^2$ CW systems on Phi Phi Island are not only for treatment of $400m^3/day$ wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.523-526
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• 2006

The target of this work was the process development of demonstration plant to produce the high quailty alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70t/y and the pi lot plant of 360 t/v had been developed. Main research contents in this step were the process performance test of pilot plant ot 360ton/year and the development of demonstration plant of 3 000 t/y which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/v showed components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.