• Journal of Animal Environmental Science
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• v.10 no.2
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• pp.101-110
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• 2004

A solid of Thermophilic Aerobic Oxidation(TAO) System was mixed with sawdust or a rice husks. After fermentation was finished, molding machine and a dryer were used, and pellet fertilizer was produced. The fertilizing experiment was carried out as five pieces by Bed soil, TAO solid(TAO-S), TAO pellet fertilizer(TAO-PF), Chemical fertilizer(NPK) and Control(no fertilizer). Growth rate of the Chinese cabbage by each treatment was examined. Analysis of microbe and soil characteristic before and after crop experiment were carried out. When the moisture contents of TAO-PF were $18\%$ and $25\%$, the occurrence rate of microbes for the storage time was increased to $80\%$ and $100\%$ respectively. However, in the $12\%$ of water content treatment was not increased microbes. The concentration of soil bacteria in TAO-PF and TAO-S for 15 day after treatment was $1.5\times10^7\~8.0\times10^7$ CFU/ml, and the concentration of bacteria for 50 day was increased to $6.3\times10^7$ and $8.3\times10^7$ CFU/ml. However, Fungus decreased. The concentration of Actinomycetes was increased in TAO solid, Bed soil and TAO-PF treatment. The TAO-S and TAO-PF treatment were normal to compare to the NPK treatment. In this experiment the height and width of the Chinese cabbage were 22.3 cm, 16.8 cm in Bed soil and 28.8 cm, 21.3 cm in TAO solid. The leaf number of TAO-S, TAO-PF and NPK treatment were similar to 39.8, 38.3, 40.3 sheet. As the result, the TAO-PF knew that use was possible with fertilizer.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.9
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• pp.526-532
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• 2015

A bioreactor filling with pellets and stones was equipped to the swine manure treatment system, which is expected to emit high concentration of odor in the process of the organic wastewater treatment system, and in comparison with the activated sludge process as the control process, the reactor operation state, treatment water quality and odor emission concentration were measured. The reactor using the bioreactor proved to be much more stable in the bubble condition, treatment water transparency, etc, and BOD removal efficiency was also much better. The removal efficiency of T-N and T-P, however, showed little difference in the two reactors. Odor, as a result of examining $NH_3-N$, $NH_3$ concentratio, and complex odor, was 4 times to 24 times less emitted in the system using bioreactor than in the activated sludge system. $H_2S$, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide were not found or were found in only 5 ppbs in each reactor and showed little difference between the two reactors. In the bioreactor process, Bacillus sp./ Pseudomonas sp. species were mainly found and in the activated sludge process, acterium sp. Chryseobacterium sp. species were mainly found.

• Journal of the Korean Society of Combustion
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• v.22 no.1
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• pp.14-22
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• 2017

Co-firing of renewable fuel in coal fired boilers is an attractive option to mitigate $CO_2$ emissions, since it is a relatively low cost option for efficiently converting renewable fuel to electricity by adding biomass as partial substitute of coal. However, it would cause reducing plant efficiency and operational flexibility, and increasing operation and capital cost associated with handling and firing equipment of renewable fuels. The aim of this study is to investigate the effects of biomass co-firing on $CO_2$ emission and capital/operating cost. Wood pellet, PKS (palm kernel shell), EFB (empty fruit bunch) and sludge are considered as renewable fuels for co-firing with coal. Several approaches by the co-firing ratio are chosen from previous plant demonstrations and commercial co-firing operation, and they are evaluated and discussed for $CO_2$ reduction and cost estimation.

• Journal of the Korean Solar Energy Society
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• v.36 no.1
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• pp.19-26
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• 2016

Biomass has been used for energy sources from the prehistoric age. Biomass are converted into solid, liquid or gaseous fuels and are used for heating, electricity generation or for transportation recently. Solid biofuels such as bio-chips or bio-pellet are used for heating or electricity generation. Liquid biofuels such as biodiesel and bioethanol from sugars or lignocellulosics are well known renewable transportation fuels. biogas produced from organic waste are also used for heating, generation and vehicles. Biomass resources for the production of above mentioned biofuels are classified under following 4 categories, such as forest biomass, agricultural residue biomass, livestock manure and municipal organic wastes. The energy potential of those biomass resources existing in Korea are estimated. The energy potential for dry biomass (forest, agricultural, municipal waste) were estimated from their heating value contained, whereas energy potential of wet biomass (livestock manure, food waste, waste sludge) is calculated from the biological methane potential of them on annual basis. Biomass resources potential of those 4 categories in Korea are estimated to be as follows. Forest biomass 355.602 million TOE, agricultural biomass 4.019 million TOE, livestock manure biomass 1.455 million TOE, and municipal organic waste 1.074 million TOE are available for biofuels production annually.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.29-35
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• 2019

The purpose of this study was to assess the applicability of acid mine drainage sludge (AMDS) pellets for the arsenic (As) stabilization and to suggest an evaluation method for arsenic stabilization efficiency in soil around abandoned coal mines. The soil samples were collected from the agricultural field around Ham-Tae, Dong-Won, Dong-Hae, and Ok-Dong coal mine. The As concentration in soil was exceeding the criteria of soil pollution level, except for Ham-Tae coal mine. The AMDS pellets are more appropriate to use by reducing dust occurrence during the transport and application process than AMDS powder. In addition, AMDS pellets were maintained the As stabilization efficiency. The application of AMDS pellets for the As stabilization in soil was assessed by column experiments. The AMDS pellets were more effective than limestone and steel slag, which used as the conventional additives for the stabilization process. The As extraction by $0.43M\;HNO_3$ or $1M\;NaH_2PO_4$ solution were appropriate evaluation methods for evaluation of As stabilization efficiency in the soil.

• Clean Technology
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• v.12 no.2
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• pp.67-77
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• 2006

A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.917-922
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• 2005

The wastewaters from textile and dyeing industries are difficult to treat due to its high pH, temperature, color intensity and non-biodegradable organic contents. This study investigated the removal of recalcitrant organics in a dyeing wastewater by using a packed bed reactor (PBR) that contained cell-immobilized pellets. The feed, obtained from an effluent of a biological treatment plant, had $SCOD_{Cr}$ of 330 mg/L and $SBOD_5$ of 20 mg/L on average. In immobilizing the cells to a Polyethylene Glycol(PEG) based medium, activated sludges from either a sewage treatment plant or an industrial wastewater treatment plant were used. When the empty bed contact time (EBCT) was above 8 hrs in the PBR, the $COD_{Cr}$ removal efficiency was over 50% and the $COD_{Mn}$ concentration was 72 mg/L or lower on average, which was substantially lower than the discharge standard of 90 mg/L. The results indicated that the optimum EBCT in the PBR was 8 hrs. The PBR with cell-immobilized pellets was effective as an advanced treatment process after an activated sludge process for treating dyeing wastewaters.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.197-203
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• 2018

Biochar is the carbon solid produced through the pyrolysis of a biomass from organic sources such as agricultural waste, animal manure, and sludge under limited or anaerobic conditions. Biochar has the effect of reducing greenhouse gases through the carbon sequestration method; additionally, biochar is known to function as a soil amendment. This experiment was conducted to evaluate the application of biochar on the growth characteristics of Chinese cabbage at Chungnam National University in Daejeon, Korea. The Chinese cabbage was grown for 50 days in a glasshouse in pots. A pruning branch was used to produce the bead and pellet forms of biochar through pyrolysis. The biochar was added to the soil at 0, 2, and 5% by weight. The Chinese cabbage with the 2% treatment of the bead form of biochar had the highest fresh weight ($149.43{\pm}15.92g\;plant^{-1}$) which was increased by 10% compared to the control ($136.91{\pm}31.46g\;plant^{-1}$). Moreover, for the 5% treatment of the bead form of biochar ($60.91{\pm}9.82g\;plant^{-1}$), the growth decreased by 57% compared to the control. As the content of the bead form of biochar increased, the shoot dry weight, leaf number, leaf length and lead width that appeared decreased. An increase in the total organic matter, Avail. $P_2O_5$, Ex. cation and EC was observed when the biochar content was increased. Our results support the application of 2% biochar in the bead form for increased growth of Chinese cabbage.