• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.04a
• /
• pp.318-322
• /
• 2004

Arsenic is a toxic and carcinogenic metalloid, whose sources in nature include mineral dissolution and volcanic eruption. Abandoned mines and hazardous waste disposal sites are another major source of arsenic contamination of soil and aquatic systems. To predict concentrations of the toxic inorganic arsenic in aqueous phase. the biogeochemical redox processes and transport behavior need to be studied together and be coupled in a reactive transport model. A new reaction module describing the fate and transport of inorganic arsenic species (As(II)), dissolved oxygen, nitrate, ferrous iron, sulfate, and dissolved organic carbon are developed and incorporated into the RT3D code.

• Journal of Environmental Health Sciences
• /
• v.27 no.3
• /
• pp.43-48
• /
• 2001

Terephthalic acid and ethylene glycol resulting form the weight-reduction process of polyester make trouble in the operation of activated sludge process. Also, polyester weight loss wastewater shows high pH, high organic strength and wide variation of organic loading. Therefore, this study was conducted in order to improve treatment efficiency by activated sludge process with Pseudomonas sp degrading components of polyester weight loss wastewater. The CO $D_{Mn}$ and BO $S_{5}$ of the waste wastewater were 560~3,000 mg/$\ell$ and 8000~3,000 mg/$\ell$, respectively. pH was 11.8~12.3. COD removal efficiency by activated sludge-coagulation process with Pseudomonas sp was 94.1~95.8% for 35 hr of hydraulic retention time. Total organic carbon removal efficiency was 97.1%. Ethylene glycol and terephthalic acid in the wastewater were completely degraded during 32 hr of hydraulic retention time.e.

• Journal of environmental and Sanitary engineering
• /
• v.11 no.2
• /
• pp.1-7
• /
• 1996

The behavior of total organic carbon (TOC) and phosphate were observed for 15 days with immobilized activated sludge using polyacrylamide (PAA) by sequencing batch reactor (SBR). In the preparation of immobilized sludge by PAA, it was found that suitable acrylamide concentration for actual wastewater treatment was to be 15% through the batch test. When SBR system was operated in the repeated aerobic and anaerobic conditions, TOC removal efficiency was 92%. The uptake rate of phosphate was increased from 1.78 mg-P/g cell/hr on the 5th day of acclimation to 2.5 mg-P/g cell/hr on the 15th day of acclimation. And the total phosphorus content in PAA bead was increased from 40 mg-P/g cell on the 1st day of operation to 55 mg-P/g cell on the 15th day of operation. From this study, lowering the volume of aeration tank was possible when PAA bead was used in wastewater treatment and long operation was also possible without the settler.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.813-816
• /
• 2009

A commercial-scale RDF boiler that its burning capacity is 400 kg-RDF/hr and steam production capacity is 2 ton/hr. It has a chain type stoker and waste heat recovery system. Heat exchanger is vertical water-pipe so that soot blowing and removal is convenient during operation. Dry scrubber, bag filter and activated carbon tower have been installed for the reduction of air pollutant gases and dust. Analysing data of pollutants from stack such as $SO_x$. $NO_x$ and dioxin shows so good results that the boiler system could comply the regulated emission limits.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.79-82
• /
• 2006

Fueled by ballooning oil prices, waste plastics are now regarded as being cheap and abundant renewable sources, removing their stigma of dirty wastes Catalytic pryolysis of plastics in liquid phase allows recovery of light fuel oil as well as green treatment of polymerics wastes, and therefore significant efforts have been devoted to this research field. In this study, catalytic Pyrolysis of LDPE was carl ied out in semi-batch reactor which equipped a unit of separation and recirculation. The effect of react ion conditions were examined by analyzing liquid oil yield and carbon number distribution of products

• Journal of the Korean Society of Industry Convergence
• /
• v.21 no.3
• /
• pp.109-115
• /
• 2018

This paper proposes the method to develop the fuel of suljigemi pellet using agricultural by-products the occurred during the manufacturing of alcohol. The goal of the development of suljigemi using biomass is to make the pellet fuel of high calorie. The suljigemi pellet is difficult to recycle waste in the manufacture company of alcohol. suljigemi pellet has the effect of zero emission as the soil conditioner using ash after burning. Also suljigemi pellet has the reduction effect of carriage fee, fuel economy and low-cost high-efficiency effects, environmentally clean fuel as CO2 emissions savings. So the technologies of the suljigemi fuel pellet are developing low carbon, green growth renewable energy fuel through futuristic energy system will be. In experiments, suljigemi pellets confirmed the calories by about 10% higher than wood pellets with the same conditions.

• Environmental Analysis Health and Toxicology
• /
• v.6 no.3_4
• /
• pp.149-154
• /
• 1991

Biodegradation of carbon tetrachloride (CTC) in denitrifying and aerobic columns was investigated under various conditions of electron-acceptor and electron-donor availability. CTC removal increased when the electron-acceptor (nitrate) injection was stopped in the denitrifying column; however, CTC remova1 decreased when electron donor (acetate) was deleted in the denitrifying and the aerobic column. Small fractions of the CTC removed appeared as chloroform, indicating that reductive dechlorination of CTC was occurring. The results from the denitrifying column support the hypothesis that CTC behaves as an electron acceptor that competes for the pool of available electrons inside the bacterial cells.

• Environmental Engineering Research
• /
• v.19 no.1
• /
• pp.47-57
• /
• 2014

The aim of this paper was to study the effect of five different waste combinations (C/N 15, C/N 20, C/N 25, C/N 30, and control) of sewage sludge coupled with sawdust and cattle manure in a pilot scale rotary drum reactor, during 20 days of the composting process. Our results showed that C/N 30 possesses a higher temperature regime with higher % reduction in moisture content, total organic carbon, soluble biochemical oxygen demand and chemical oxygen demand; and higher % gain in total nitrogen and phosphorus at the end of the composting period implying the total amount of biodegradable organic material is stabilized. In addition, $CO_2$ evolution and oxygen uptake rate decreased during the process, reflecting the stable behavior of the final compost. A Solvita maturity index of 8 indicated that the compost was stable and ready for usage as a soil conditioner. The results indicated that composting can be an alternate technology for the management of sewage sludge disposal.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.512-515
• /
• 2000

A parallel reactor system which is consisted of two trickle bed reactors (TBR) was developed for the biodegradation of trichloroethylene (TCE) in waste gas stream. The reactor were packed with porous ceramic materials and Burkholderia cepacia G4 was inoculated to form biofilms. Each reactor was operated alternatively in TCE degradation or reactivation mode, and the effect of switching time on TBR performance was investigated. The MO (monooxygenase) activity during the TCE transformation decreased below 10 % within 24 hr, but could be recovered to the initial high level within 10 hr after supplying the reactivation medium supplemented with phenol as a carbon source. This shows that the parallel TBR system has a great potential for the long-term stable treatment of TCE.

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.250-255
• /
• 2005

Trichoderma inhamatum KSJ1, a filamentous fungus, isolated from rotten wood showed high ability to hydrolysis of cellulosic materials. Enzyme productivity by strain KSJ1 was high in the cultivation using carbon sources such as cellulosic materials and lignocellulosic wastes as rice straw and paper waste. In previous study peptone was one of optimum organic nitrogen sources in producing cellulases for saccharification of food wastes. However, it was too expensive using peptone as organic nitrogen source, so, in this study, soybean and yeast were applicated to substitute peptone. Yeast showed producing high enzyme activity, so it was estimated that yeast is available in producing cellulase using Trichoderma inhamatum KSJ1 at industrial Production.