• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.24-30
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• 1999

A biological filter for treatment of toluene among volatile organic compounds was studied. The investigation was conducted using specially built stainless steel columns packed with granular activated carbon and cold for removal of toluene. The G.A. and mold as filter material was also coated with Pseudomonas putida microorganisms.The biofilter unit was operated in the condition of moisture content vairation at gas loading rate of 12.5 l/min. Gaseous toluene taken from tedlar bag was analyzed by the use of G.C equipped with F.I.d detector. The removal efficiency of gaseous toluene was 95% at average inlet concentration of 950 ppm during bio-degradation operating condition. Effective removal efficiency was obtained with moisture content 27.5% at activated carbon and 32% at mold in this study. The effective operating condition were obtained with pH 6-8, temperature 28-42℃ for microbial degradation at gas loading rate of 12.5 l/min in packed material.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.11
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• pp.776-780
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• 2013

TPH degrdation patterns in diesel contaminated soil was investigated with microwave radiation. When microwave radiation on the soil was applied, temperature increment of the aridic soil was quite low, but temperature in the moist soil was dramatically increased even if short period of running time. Up to 20% of the moisture content, the higher moisture content has more increment of temperature, whereas over 20% of the moisture content, temperature in the soil was rather decreased. when 100~700 W power of microwave radiation was applied into the contaminated soil, a lot of TPH removals was observed under 300 W, but negligible increment of TPH removal was detected over 300 W. 60% of TPH removal was achieved with initial 20% moisture content and microwave radiation. Additional 25% removal was accomplished when moisture content was kept constant during radiation period. It indicated that maintaining of constant moisture is an important factor for TPH removal with microwave radiation because moisture and temperature in the soil are decreased with reaction time.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.2
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• pp.115-120
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• 2024

In this study, the extent of water removal in the high-moisture coal was measured. The simplified adsorption model was developed to predict the extent of water removal. The water removal was observed to increase up to 25% at saturation condition of 25℃. The modeling work shows that adsorption contributes the water removal only by 3%, whereas other factors such as CO₂ solubility and wettability would be responsible for the water removal.

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.88-94
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• 1998

This study was investigated the application of biofiltration using cometabolic process to remediate gaseous toluene that are highly recalcitrant to adsorption, absorption and biodegradation. The investigation was conducted using specially built steel columns packed with granular activated carbon for removal of toluene and G.A.C was also coated with Pseudomonas putida microorganisms by addition of KH$_{2}$PO$_{4}$. The biofilter unit was operated in the condition of dry and 27.5% moisture content at gas loading rate of 12.5 l/min. Gaseous toluene taken from tedlar bag was analyzed by the use of G.C. equipped with F.I.D. detector. The removal efficiency of gaseous toluene was 85% at average inlet concentration of 970 ppm during dry operating condition. For gaseous toluene, 91% removal efficient was obtained at the filter material with moisture content and 97% removal efficiency was obtained with Pseudomonas putida microorganisms at gas loading rate of 12.5 l/min.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.2
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• pp.55-60
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• 2014

The present study has been conducted to develope a heating system for a green house with heat from underground air at Jeju Island. The temperature of the air deposited in the underground is $16{\sim}18^{\circ}C$ throughout the year, and it also has a large amount of moisture. Therefore, the air could not directly used for the heating of a green house. In this study, a heat pump with dehumidification function has been developed, which consisted of three evaporators, where the moisture removal occurs, accompanied by temperature drop. The dropped temperature is recovered, while passing through a series condenser. The air temperature increased from $17^{\circ}C$ to 35 with a 2.1 kg/h of moisture removal rate. The developed system moisture removal performance shows 0.91 kg/kWh.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.457-464
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• 2003

The purpose of this study was to develop a pilot scale bio-filter system removing ammonia gas with microorganisms. The system consisted of chaff(filter medium), a blower, a temperature sensor, a moisture sensor, a solenoid valve, and a heating system. Temperature and moisture contents were controlled via a PC to provide the microorganisms with proper environment. The microorganisms used in this study were Bacillius. coagulans NLRI T-6 and Pseudononas. putida NLRI S-21 of bacilli. Performance tests were performed to evaluate gas removal rate during 20 days. The result was shown that the removal rate was high in early days and gradually dropped below 90% without injecting the microbes. However, it was shown that when injecting the microbes, the removal rate was almost 100% and pH value was maintained at between 7 and 9 during the whole twenty-day period.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.728-736
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• 1996

Solid/Liquid(S/L) separation is crucial for biological treatment of animal wastewater. Liquid portion from S/L separation has less BOD-load and proper post-strip treatment can be obtained . Screen or declined sieve was normally used to separate the solid parts. For better separating efficiency a vibration and a cylindrical separator were constructed and tested. The results are summarized as follows : Solids removal efficiency and moisture content of separated solid were 15-26% and 85-88%, respectively for the vibration separator. For the cylindrical separator, solid removal efficiency and moisture content of solid were 16-39% and 86-89% , respectively. The greatest amount of drymatter was obtained when operating vibration separator with 10。 inclination and 100% vibrating power. For the cylindrical separator maximum efficiency was obtained with 40rpm and 19 inclination . The vibration and the cylindrical separator have shown 21% and 26% in BOD removal, respectively. These two types of separator were proved to be applicable methods for animal wastewater separation.

• Textile Coloration and Finishing
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• v.11 no.3
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• pp.41-48
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• 1999

The removal of hemoglobin from acrylic acid grafted Nylon fabrics has been investigated. In order to change detergency of Nylon 6 fabric, acrylic acid(AA) were graft copolymerized on Nylon fabric using ammonium persulfate(APS) as a initiator, and then acrylic acid grafted Nylon was treated with NaOH solution. The graft ratio increased linearly with increasing acrylic acid concentration. The graft ratio was the highest when the concentration of APS was 0.05%, and it decreased as the concentration of APS increased. The surface of Nylon fabric became rough due to graft. Moisture regain was increased by graft and alkaline treatment, contact angle was also improved compared with the ungrafted. The hemoglobin was easily solubilized and removed from grafted Nylon fabric, while it was difficult to remove hemoglobin from ungrafted Nylon fabric. The effects of graft on removal of hemoglobin was related with increase of moisture regain and transformation of COOH to COONa by alkaline treatment.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.687-694
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• 1999

This study was conducted to develop new drying process for automatic control and marine engi-neering system. Air-water tests were carried out to investigate dryer performance. The dispersed flow in he dryer test apparatuses was also simulated by using a numerical code which solves the Dittus-Boelter equation for continuous liquid phase and the Reynolds equation of droplet motion for continuous liquid phase and the Reynolds equation of droplet motion for dispersed phase to predict droplet removal efficiency. Proper conditions for dehumidification were optimized by response ambient conditions. When the selected indexes were constrained in the range of 85-98% moisture content above $15^{\circ}$ and more than mass flow rates of moist air 750kg/h. The numerical results were compared with the experimental data pertaining to the removal effi-ciency at chamber stage and overall pressure drop along concentric tubes Good agreement was obtained as for the efficiency while relatively poor agreement was obtained for the relative humidity. The results also showed that the efficiency depended strongly on the relative humidity at the inlet condition which indicated the importance of estimating the heat exchanger length. Effects of some design parameters in both removal efficiency and breakthrough onset condition are discussed.

• Tribology and Lubricants
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• v.38 no.4
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• pp.121-127
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• 2022

This study presents the development of an integrated oil purification system consisting of moisture removal, oil flushing, and oil filtering devices. In this system, the oil flushing device is combined with a micro-bubble generator. Oil purification is necessary for ensuring the high performance of the lubricant through the efficient removal of contaminants and thus enables good maintenance of mechanical systems. The developed purification system removes moisture, varnish, and solid particles. Moreover, during oil purification, the oil flushing device separates foreign materials and contaminants remaining in the lubricating oil piping or mechanical systems. The microbubble generator, which is combined with the oil flushing device, can separate harmful contaminants, such as sludge, wear particles, and rust, from piping or lubrication systems through the cavitation effect. Moisture is removed using a double high-vacuum chamber, while sludge and varnish are removed via electro-absorption using a high-voltage generator. Additionally, the total maintenance cost of the system is reduced through the use of domestically fabricated cartridge filters composed of glass fiber and cellulose. The heater, which maintains the temperature of the lubricant at 60℃, can process 41,000 L of lubricant simultaneously. Multiple tests confirmed that the proposed integrated purification system exhibits good performance in oil flushing and removal of water and varnish.