• Title, Summary, Keyword: Methane

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Effects of Water Management Rice Straw and Compost on Methane Emission in Dry Seeded Rice (벼 건답직파재배에서 물관리와 볏짚 및 퇴비가 메탄배출에 미치는 영향)

  • Ko, Jee-Yeon;Kang, Hang-Won;Park, Kyong-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.29 no.3
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    • pp.212-217
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    • 1996
  • Investgated in relation to Methane emission on dry seeded rice culture was flooding and intermittent irrigation and application time of rice straw in clayey soil. Negative peaks of the methane emission before 3 leaves stage which were never seen in the transplanting cultivation was found and the highest peak was come out at the heading stage. Total amount of emitted methane was lower about 40% than that of the transplanted. Methane emission decreased about 19% by intermittent irrigation. Compost and NPK application reduced methane about 70% and 80% in comparisin with rice straw. Rice straw application one month before sowing reduced methane emission than the application just before sowing.

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Analysis of Methane from Screened Soil of Closed Landfill and Application of Landfarming for the Reduction of the Methane (사용종료 매립지 선별토양의 메탄 발생 분석 및 토양경작기술 적용 효과 연구)

  • Kim, Kyung;Yang, Jae-Kyu;Chang, Yoon-Young
    • Journal of Soil and Groundwater Environment
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    • v.15 no.5
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    • pp.40-45
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    • 2010
  • In this study, methane production by reuse of screened soil of landfill was estimated and the effect of application of landfarming for the reduction of methane was investigated. The study soil sampled from S closed landfill contains VS 9.8~12.8% and its BOD/COD is 0.31~0.33 which is more than three times over 0.1, the BOD/COD stabilization criteria of Ministry of Environment. The effective remediation technology for the reduction of organics of soil, landfarming was applied to the screened soil for 60 days. VS and TPH removal showed 5.2~8.3% and 67~74% respectively, and the reduction of VS until 30 day charged 70% of the total reduction. BMP test showed 27.77~30.46 mL $CH_4$/g VS and total methane production from total screened soil for remediation is expected about 260.4 $CH_4$ ton. Expected amount of methane production of the screened soil by landfarming application is 12.9 $CH_4$ ton, which shows 95% gas reduction effect and landfarming is effective for the reduction of methane production from screened soil of landfill.

Methane hydrate formation Using Carbon Nano Tubes (탄소나노튜브를 이용한 메탄 하이드레이트 형성)

  • Park, Sung-Seek;Seo, Hyang-Min;Kim, Nam-Jin
    • 한국신재생에너지학회:학술대회논문집
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    • pp.549-552
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    • 2009
  • Methane hydrate is crystalline ice-like compounds which formed methane gas enters within water molecules composed cavity at specially temperature and pressure condition, and water molecule and each other from physically-bond. $1m^3$ hydrate of pure methane can be decomposed to the maximum of $172m^3$ at standard condition. If these characteristics of hydrate are reversely utilized, natural gas is fixed into water in the form of hydrate solid. Therefore the hydrate is considered to be a great way to transport and store natural gas in large quantity. Especially the transportation cost is known to be 18~24% less than the liquefied transportation. However, when methane hydrate is formed artificially, the amount of consumed gas is relatively low due to a slow reaction rate between water and methane gas. In this study, for the better hydrate reaction rate, there is make nano fluid using ultrasonic dispersion of carbon nano tube. and then, Experiment with hydrate formation by nano fluid and methane gas reaction. The results show that when the carbon nano tubes of 0.004 wt% was added to pure water, the amount of consumed gas was about 300% higher than that in pure water and the hydrate formation time decreased.

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Hydrogen production by catalytic decomposition of propane-containing methane over N330 carbon black in a fluidized bed (유동층 반응기에서 N330 카본 블랙 촉매를 이용한 프로판을 포함한 메탄의 촉매분해에 의한 수소 제조)

  • Lee, Seung-Chul;Lee, Kang-In;Han, Gui-Young
    • 한국신재생에너지학회:학술대회논문집
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    • pp.761-764
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    • 2009
  • The thermocatalytic decomposition of methane is an environmentally attractive approach to $CO_2$-free production of hydrogen. The fluidized bed was proposed for the continuous withdraw of product carbon from the reactor. The usage of carbon black was reported as stable catalyst for decomposition of methane. Therfore, carbon black (DCC-N330) is used as catalyst. A fluidized bed reactor made of quartz with 0.055 m I.D. and 1.0 m in height was selected for the thermo-catalytic decomposition. The porpane-containg methnae decomposition reaction was operated at the temperature range of 850-900 $^{\circ}C$ methane gas velocity of 1.0 $U_{mf}$ and the operating pressure of 1.0 atm. In this work, propane was added as reactant to make methane conversion higher. Therefore we compared with methane conversion and pre-experiment methane conversion that using only methane as reactant. The carbon black, after experiment, was measured in particle size and surface area and analyzed surface of the carbon black by TEM.

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Thermal Decompostion of Methane Using Catalyst in a Fluidized Bed Reactor (유동층반응기에서 촉매를 이용한 메탄 열분해)

  • Jang, Hyun-Tae;Lee, Ji-Yun;Cha, Wang-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.2
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    • pp.487-492
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    • 2008
  • In this paper, Thermocatalytic decomposition of methane in a fluidized bed reactor (FBR) was studied. The technical approach is based on a single-step decomposition of methane over carbon catalyst in air/water vapor free environment. The factors affecting methane decompostion catalyst activity in methane decomposition reactions were examined. The fluidization phenomena in a gas-fluidized bed of catalyst was determined by the analysis of pressure fluctuation properties, and the results were confirmed with characteristics of methane decomposition. The effect of parameters on the H2 yield was examined for methane decompostion. The decompstion rate was affected by the fluidization quality such as mobility, U-Umf, carbon attrition, elutriation and effectiveness density of fluidization gas.

Hydrogen and Methane Production from Mixture of Food Wastewater and Swine Wastewater using Two-Phase Anaerobic Process (이상 혐기성 공정을 이용한 음식물류폐기물폐수와 양돈폐수의 혼합액으로부터 수소 및 메탄 생산)

  • Kim, Choong-Gon;Kang, Seon-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.3
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    • pp.299-306
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    • 2008
  • This study has been conducted to derive the bio-energy, hydrogen and methane production, from mixture of food wastewater and swine wastewater, the high strength organic wastewater and to increase effluent quality. To overcome this limitation in one-phase anaerobic process, two-phase anaerobic process combining hydrogen fermenter and methane fermenter was applied. In this system $2,323ml\;H_2/L$ was produced daily from Run II where 500 ml of heattreated sludge in methane fermenter was injected, and methane produced from methane fermenter did not show big difference regardless of the amount of returning sludge at each Run. It was concluded that the two-phase anaerobic process was the appropriat process to produce hydrogen and methane simultaneously and stably. Influent $TCOD_{Cr}$ to two-phase anaerobic process showed the range of 132~145 g/L(average 140 g/L), and effluent $TCOD_{Cr}$ range was 25~40 g/L(average 32 g/L), and organic removal efficiency showed 71~82%(average 76.3%).

Anaerobic digestion of food waste to methane at various organic loading rates (OLRs) and hydraulic retention times (HRTs): Thermophilic vs. mesophilic regimes

  • Kumar, Gopalakrishnan;Sivagurunathan, Periyasamy;Park, Jong-Hun;Kim, Sang-Hyoun
    • Environmental Engineering Research
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    • v.21 no.1
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    • pp.69-73
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    • 2016
  • Generation of food waste is a serious issue that needs to be addressed worldwide. Developing suitable treatment methods while generating energy (methane) is a common practice for sustainable treatment of waste. In this study, methane generation by food waste was investigated in mesophilic and thermophilic regimes at various hydraulic retention times (HRTs) and organic loading rates (OLR). In temperature regimes, influent concentrations and HRTs ranged from 30 to 110 g COD/L and 18 to 30 days, respectively, which corresponding to an OLR of 1.0 to $6.1kg\;COD/m^3-d$. Better methane production and organic removal was observed under thermophilic conditions because of the enhanced hydrolysis of complex polymers and microbial activity at higher temperature. The peak methane productivities attained in thermophilic and mesophilic regimes were 1.30 and $0.99m^3/m^3-d$, respectively. The maximum methane yields were achieved at 50 g COD/L and HRT of 24 d in both cases, and the values were 264 and $221m^3/ton$ COD, respectively. The results of this study will facilitate the development of sustainable methane production technologies using food waste as a feedstock.

Correlation between Methane (CH4) Emissions and Root Aerenchyma of Rice Varieties

  • Kim, Woo-Jae;Bui, Liem T.;Chun, Jae-Buhm;McClung, Anna M.;Barnaby, Jinyoung Y.
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.381-390
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    • 2018
  • Percentage of aerenchyma area has been closely linked with amounts of methane emitted by rice. A diversity panel of 39 global rice varieties were examined to determine genetic variation for root transverse section (RTS), aerenchyma area, and % aerenchyma. RTS and aerenchyma area showed a strong positive correlation while there existed no significant correlation between RTS area and % aerenchyma. Five varieties previously shown to differ in methane emissions under field conditions were found to encompass the variation found in the diversity panel for RTS and aerenchyma area. These five varieties were evaluated in a greenhouse study to determine the relationship of RTS, aerenchyma area, and % aerenchyma with methane emissions. Methane emissions at physiological maturity were the highest for 'Rondo', followed by 'Jupiter', while 'Sabine', 'Francis' and 'CLXL745' emitted the least. The same varietal rank, 'Rondo' being the largest and 'CLXL745' the smallest, was observed with RTS and aerenchyma areas. RTS and aerenchyma area were significantly correlated with methane emissions, r = 0.61 and r = 0.57, respectively (P < 0.001); however, there was no relationship with % aerenchyma. Our results demonstrated that varieties with a larger root area also developed a larger aerenchyma area, which serves as a gas conduit, and as a result, methane emissions were increased. This study suggests that root transverse section area could be used as a means of selecting germplasm with reduced $CH_4$ emissions.

Effects of tannin supplementation on growth performance and methane emissions of Hanwoo beef cows

  • Jeong, Sinyong;Lee, Mingyung;Jeon, Seoyoung;Kang, Yujin;Kang, Heejin;Seo, Seongwon
    • Korean Journal of Agricultural Science
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    • v.45 no.3
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    • pp.463-473
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    • 2018
  • The objective of this study was to investigate the effects of dietary hydrolysable tannin on growth performance and methane emissions of Hanwoo beef cows. Fifteen cows participated in a seven-week experiment. The cows were stratified by initial methane emissions and assigned to one of two treatments: Control and tannin supplementation. Commercial hydrolysable tannin was top-dressed to a concentrate mix at 3 g/kg based on the dry matter. Enteric methane production was measured for 4 consecutive days at 1 week before and 1, 3 and 7 weeks after the initiation of the experiment using a laser methane detector. The feed intake was measured daily during the methane measurement periods and an additional two days prior to each measurement. The body weight of the cows was measured every 4 weeks. Hydrolysable tannin had no effect (p > 0.05) on body weight, average daily gain, dry matter intake (DMI) and feed conversion ratio. After one week, the methane emission of the tannin supplementation group was 3.66 ppm-m / kg DMI, which was about 3.4% lower (p = 0.078) than that of the control group; however, this tendency disappeared at 3 weeks after the start of the experiment (p > 0.05). The results of this study show that hydrolysable tannin supplementation can reduce enteric methane emissions for a limited period in Hanwoo beef cows. More research, however, is needed to determine the optimal level of hydrolysable tannin supplementation to reduce enteric methane emissions for a longer period without adversely affecting the animal performance of Hanwoo beef cattle.

Evaluation of Leachate Replacement Effect on Solid State Anaerobic Digestion of Dairy Manure and Sawdust Bedding Mixtures

  • Jo, Hyeonsoo;Lee, Seunghun;Kim, Eunjong;Ahn, Heekwon
    • Korean Journal of Soil Science and Fertilizer
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    • v.50 no.4
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    • pp.293-305
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    • 2017
  • This experiment was conducted to evaluate the effect of leachate replacement frequency on solid state anaerobic digestion (SSAD) of dairy manure using 22 L volume lab-scale digesters at mesophilic temperature ($37^{\circ}C$) in batch mode. Three different leachate replacement strategies (no replacement, once every three days, and once every nine days) were applied and three digesters per each treatment were operated for 45 days. Results showed that leachate replacement test unit every nine days resulted in 1.6 times more methane production ($53.8N{\cdot}mL\;g^{-1}{\cdot}VS$) from SSAD compared to test unit every three days ($34.0N{\cdot}mL\;g^{-1}{\cdot}VS$). No leachate replacement strategy applied group showed slightly higher methane production ($56.3N{\cdot}mL\;g^{-1}{\cdot}VS$) than every nine days replaced one. When added the methane production potential of replaced leachate itself to the methane produced from digester, leachate replacement every nine days resulted in quite similar methane production ($56.5N{\cdot}mL\;g^{-1}{\cdot}VS$) to no leachate replacement group. Even though methane production potential of replaced leachate itself added to the methane produced from digester, every three days replacement showed only $34N{\cdot}mL$ methane production per gram of volatile solids. These results suggest that farmers do not need to replace leachate during SSAD of dairy manure and sawdust mixture in order to maximize methane production. If there are any concerns with accumulation of inhibiting substances in the digester, the 9-day cycle leachate replacement is appropriate.