• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.794-800
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• 2011

To develop biochar for soil conditioner using water plants, characteristics of nutrients release of biochars were investigated under different water plants, manufacturing times and manufacturing temperatures. Under different water plants for manufacturing biochar, the concentrations of T-N and $P_2O_5$ in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. The concentrations of $K_2O$ in the water were in the order of TYHOR ${\fallingdotseq}$ CRXDM > ZIZLA > PHRCO > MISSA. Under different manufacturing times for biochar, the concentrations of T-N, $P_2O_5$ and $K_2O$ in the water with biochars were higher in the order of 2 hr > 30 min ${\fallingdotseq}$ 1 hr. The concentrations of T-N, $P_2O_5$ and $K_2O$ in the water with biochars were on the order of $350^{\circ}C$ > $500^{\circ}C$ > $600^{\circ}C$ under different manufacturing temperatures. Total amounts of T-N and $K_2O$ releases in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. Using biochars by water plants, total amounts of $P_2O_5$ releases in the water with biochars were on the order of CRXDM > ZIZLA > MISSA >PHRCO > TYHOR. The results of this study suggest that biochars by water plants can supply some of the nutrient requirements of crops and can be a valuable fertilizer.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1243-1252
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• 2019

The purpose of this study is to investigate the optimum conditions of biomass pretreatment with potassium hydroxide (KOH) for efficient utilization of cellulose, hemicellulose and lignin from Miscanthus. The optimization of variables was performed by response surface methodology (RSM). The variation ranges of the parameters for the RSM were potassium hydroxide 0.2~0.8 M, reaction temperature 110~190℃ and reaction time 10~90 min. The optimum conditions of alkali pretreatment from Miscanthus were determined as follows: concentration of KOH 0.47 M, reaction temperature 134℃ and reaction time 65 min. At the optimum conditions, the yield of cellulose from the solid fraction after pretreatment was predicted to be 95% by model prediction. Finally, 66.1 ± 1.1% of cellulose were obtained by verification experiment under the optimum conditions. The order contents of solid extraction were hemicellulose 26.4 ± 0.4%, lignin 3.7 ± 0.1% and ash 0.5 ± 0.04%. The yield of ethanol concentration of 96% was obtained using separated saccharification and fermentation.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.704-711
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• 2010

Lignocellulose ($2^{nd}$ generation) is difficult to hydrolyze due to the presence of lignin and the technology developed for cellulose fermentation to ethanol is not yet economically viable. However, recent advances in the extremely new field of biotechnology for the ethanol production are making it possible to use of agriculture residuals and nonedible crops biomass, e.q., rice straw and miscanthus sinensis, because of their several superior aspects as agriculture residual and nonedible crops biomass; low lignin, high contents of carbohydrates. In this article, as the basic study of AP(Ammonia Percolation), the properties and the optium conditions of process were established, and then the overall efficiency of AP was investigated. The important independent variables for AP process were selected as ammonia concentration, reaction temperature, and reaction time. The percolation condition for maximizing the content of cellulose, the enzymatic digestibility, and the lignin removal was optimized using RSM(Response Surface Methodology). The determined optimum condition is ammonia concentration; 11.27%, reaction temperature; $157.75^{\circ}C$, and reaction time; 10.01 min. The satisfying results were obtained under this optimized condition, that is, the results are as follows: cellulose content(relative); 39.98%, lignin content(relative); 8.01%, and enzymatic digestibility; 85.89%.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.117-117
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• 2017

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.151-151
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• 2017

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.04a
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• pp.105-105
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• 2018

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6B
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• pp.345-354
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• 2012

The main objective of this study is evaluating experimentally roughness coefficients of the Korean riparian vegetations based on the n-VR analysis to suggest the practical guideline for Manning's roughness coefficients for the channel design. Hydraulic experiments were conducted for Phragmites japonica Steud., Miscanthus sacchariflorus (Maxim.) Benth., and Phragmites communis Trin. under both submerged and un-submerged conditions, and the n-VR relationships are developed for each grass. Three vegetations tested in this study can be considered as same group showing similar roughness characteristics, though these grasses are strongly affected by vegetation stiffness. Vegetation roughness are also affected by the growth state of plants according to experimental results of Phragmites communis Trin.

• Korean Journal of Environment and Ecology
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• v.13 no.3
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• pp.288-294
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• 1999

경상북도 안동 사문암지역 및 부근의 화강암지역에 분포하는 암석, 토양 및 식물체에 함유되어 있는 원소의 농도를 조사한 결과는 다음과 같다. 본 조사지역에분포하는 사문암에 함유되어 있는 주요 전이원소 함량(Ni 1.164ppm. Cr 366ppm. Co 109ppm. Fe 7.48%) 및 다른 대부분의 전이원소(Sc, Mn, Cu)도 화강암보다 높았으며 우리나라 efms 지역의 사문암에 함유되어 있는 농도와 비교하여 볼 때 매우 유사한 경향을 보이고 있다. 사문아토양의 경우 암석풍화토양 및 산림토양 모두 화강암토양에 비해 Ni, Co, Cr, Fe, Sc, Mn, Cu, Mg, Zn 농도가 높았으며 Pb는 반대의 경향을 나타내었다. 토양내 원소 함량은 이들의 모암에 함유되어 있는 원소 함량의 변화와 일치하고 있으며 같은 모암인 경우 산림식생의 영향에 따라 면 원소들의 차이가 다소 나타났다. 식물체 내 원소의 농도는 토양의 농도에 비해 모두 낮았다. 참억새, 쑥, 소나무에 함유되어 있는 원소별 평균 농도는 모두 동일종간 대부분의 전이원소(Ni, Co, Cr, Fe) 및 As 농도가 화강암토양에 비해 사문암토양에서 더높았다 사문암토양에서 생육하는 식물체 3종 모두 대부분의 원소(Ni, Co, Cr. As, Sc, Fe) 함랴이 지하부에서 더 높았으며 Zn과 Mo는 지상부와 지하부의 농도 차이가 크게 나타나지 않았다 화강암토양에서 생육하는 식물체의 경우 원소별 지상부 및 지하부의 농도차이는 사문암토양에 비해 크지 않았다.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.657-663
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• 2012

To evaluate effects of water temperatures on nutrient releases of submerged plants in lake reservoir, COD, T-N and T-P releases of submerged plants were investigated for 60 days under different incubation temperatures ($5^{\circ}C$ and $25^{\circ}C$) in columns. The amounts of COD releases by Carex dimorpholepis were $60.4mg\;L^{-1}$ at $5^{\circ}C$ and $78.0mg\;L^{-1}$ at $25^{\circ}C$. In Miscanthus sacchariflorus, the amounts of COD releases were $62.5mg\;L^{-1}$ at $5^{\circ}C$ and $70.5mg\;L^{-1}$ at $25^{\circ}C$. The amounts of T-N releases in Carex dimorpholepis at $5^{\circ}C$ and $25^{\circ}C$ were 45.8 and $60mg\;L^{-1}$, respectively. In Miscanthus sacchariflorus, the amounts of T-N releases were $55.7mg\;L^{-1}$ at $5^{\circ}C$ and $61.0mg\;L^{-1}$ at $25^{\circ}C$. At $5^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 5.65 and $7.10mg\;L^{-1}$, respectively. At $25^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 8.70 and $8.18mg\;L^{-1}$, respectively. In the column experiment, the amounts of COD, T-N and T-P releases by submerged plants at $25^{\circ}C$ were generally higher than those at $5^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.144-152
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• 2011

BACKGROUND: Eutrophication occurs occasionally in flood control reservoirs around Juam lake in summer and early autumn. Lakeside macrophyte which is one of internal pollutants effects on water quality when it is submerged during water surface is rising after rainy season. METHODS AND RESULTS: To improve water the quality of water from water supply source and to establish the management plan of submerged plants in flood control reservoirs around Juam Lake, the removal and release velocities of nutrients by submerged plants in site 1 and 2 were investigated. Removal or release velocity constant (K) of COD by Carex dimorpholepis Steud in column was 0.07~0.18 $day^{-1}$ at 0~4 days after flooding, -0.23~-0.17 $day^{-1}$ at 5~19 days after flooding and -0.28~0.03 $day^{-1}$ at 20~33 days after flooding. Removal or release velocity constant (K) of T-N by Carex dimorpholepis Steud was 0.02 $day^{-1}$ at 0~4(8) days after flooding, -0.13~-0.10 $day^{-1}$ at 5(9)~33 days after flooding in column. Removal or release velocity constant (K) of T-P by Carex dimorpholepis Steud was 0.05~0.06 $day^{-1}$ at 0~4 days after flooding, -0.14~-0.09 $day^{-1}$ at 5~33 days after flooding. Release velocity constant (K) of nutrients by Miscanthus sacchariflorus Benth was lower than that by Carex dimorpholepis Steud. In site 1, the amount of nutrients release by Carex dimorpholepis Steud was 6,719 kg/month/area for COD, 2,397 kg/month/area for T-N and 466 kg/month/area for T-P. The amounts of nutrients release by Carex dimorpholepis Steud were higher than those by Miscanthus sacchariflorus Benth in both sites. CONCLUSION(s): The results of this study suggest that COD, T-N and T-P in water quality of Juam lake were strongly influenced by submerged plants in flood control reservoirs.