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Operating Characteristics of 1 $Nm^3/h$ Scale Synthetic Natural Gas(SNG) Synthetic Systems (1 $Nm^3/h$ 규모 합성천연가스(SNG) 합성 시스템의 운전 특성)

  • Kim, Jin-Ho;Kang, Suk-Hwan;Ryu, Jae-Hong;Lee, Sun-Ki;Kim, Su-Hyun;Kim, Mun-Hyun;Lee, Do-Yeon;Yoo, Yong-Don;Byun, Chang-Dae;Lim, Hyo-Jun
    • Korean Chemical Engineering Research
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    • v.49 no.4
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    • pp.491-497
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    • 2011
  • In this work, we proposed the three different reactor systems for evaluating of synthetic natural gas(SNG) processes using the synthesis gas consisting of CO and $H_2$ and reactor systems to be considered are series adiabatic reaction system, series adiabatic reaction system with the recirculation and cooling wall type reaction system. The maximum temperature of the first adiabatic reactor in series adiabatic reaction system raised to 800. From the these results, carbon dioxide in product gas as compared to other systems was increased more than that expected due to water gas shift reaction(WGSR) and the maximum $CH_4$ concentration in SNG was 90.1%. In series adiabatic reaction system with the recirculation as a way to decrease the temperature in catalyst bed, the maximum $CH_4$ concentration in SNG was 96.3%. In cooling wall type reaction system, the reaction heat is absorbed by boiling water in the shell and the reaction temperature is controlled by controlling the amount of flow rate and pressure of feed water. The maximum $CH_4$ concentration in SNG for cooling wall type reaction system was 97.9%. The main advantage of the cooling wall type reaction system over adiabatic systems is that potentially it can be achieve almost complete methanation in one reactor.

Effects of Dissolved Compounds in Groundwater on TCE Degradations Reaction by Nanoscale Zero-Valent Iron (나노영가철의 TCE 분해반응 시 지하수 용존물질의 영향)

  • Kim, Tae-Ho;Kim, Hong-Seok;Lee, Jin-Yong;Cheon, Jeong-Yong;Lee, Kang-Kun;Hwang, In-Seong
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.6
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    • pp.413-419
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    • 2011
  • Nanoscale zero-valent iron (NZVI) particles were tested as remediation media for groundwater contaminated by organic pollutants (e.g., TCE, trichloroethylene). The contaminated groundwater contained anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, and $HCO_3^-$) and natural organic matter (NOM). Treatability of commercial NZVI particles (NANOFER 25, Nanoiron, Czech) was tested by using a synthetic groundwater and the field groundwater samples. More than 95% of 1.8 mM TCE was removed within 20 hours with a NZVI dosage of 25 g/L ($k=0.15hr^{-1}$). Repetitive degradation experiments revealed that the removal capacity of NANOFER 25 was 0.19 mmole TCE/g NZVI. TCE degradation reactions were not substantially affected by the presence of each anion with concentrations as high as 100 times the average field concentrations. However, when the four anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, $HCO_3^-$) were present simultaneously. the degradation reactivity and removal capacity were decreased by 60% ($k=0.069hr^{-1}$) and 10%, respectively. The k value of TCE degradation in the presence of NZVI (25 g/L) with dissovled organic carbon of 2.5 mg/L was also decreased by 84% ($k=0.025hr^{-1}$). In the experiments with the field groundwater, more than 90% of $1.8{\mu}M$ TCE, which is the concentration of TCE at the source zone, was removed within 10 hours with a NANOFER 25 dosage of 25 g/L. The results imply that the contaminated groundwater can effectively be treated by NANOFER 25 with more information on the hydrogeology of the site.

Manufacturing of the Enhances Antioxidative Wine Using a Ripe Daebong Persimmon (Dispyros kaki L) (대봉감 연시를 이용한 항산화 활성이 강화된 와인 제조)

  • Joo, Ok-Soo;Kang, Su-Tae;Jeong, Chang-Ho;Lim, Jong-Woo;Park, Yeong-Gyu;Cho, Kye-Man
    • Journal of Applied Biological Chemistry
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    • v.54 no.2
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    • pp.126-134
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    • 2011
  • In this study, the characteristics of alcohol fermentation using ripe Daebong persimmon juice were studied in static fermentation condition by Saccharomycess cerevisiae CS02 in an effort to develop new types of functional wine. Attempts were made to modify the ripe Daebong persimmon juice in order to find suitable conditions for alcohol fermentation. The modified ripe Daebong persimmon juice that was most suitable for alcohol fermentation contained $24^{\circ}brix$ of sugar supplemented with sucrose as a carbon source and 0.5 g/L of $(NH_4)_2HPO_4$ as a nitrogen source. After 9 days of fermentation at $25^{\circ}C$, $12.2{\pm}0.02%$ of alcohol was produced from the modified juice and its pH markedly decreased to $3.97{\pm}0.02$. The wine contained free sugar such as fructose ($0.12{\pm}0.02$ g/L), some organic acids such as malic acid ($35.92{\pm}0.24$ g/L), succinic acid ($8.12{\pm}0.03$ g/L), oxalic acid ($22.14{\pm}0.11$ g/L), and citric acid ($13.63{\pm}0.08$ g/L), as well as some flavanols and phenolic acids such as catechin gallate ($38.99{\pm}0.32$ mg/L), epicatechin gallate ($110.21{\pm}0.16$ mg/L), gallic acid ($163.88{\pm}1.11$ mg/L), epigallocatechin ($15.97{\pm}0.18$ mg/L), and tannic acid ($13.36{\pm}0.02$ mg/L). In addition, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (84.25%) and $ABTS^{\cdot+}$ radical (99.65%) scavenging activities were increased significantly with a corresponding increased in the organic acid and phenolic acid contents, but decreased in the flavonoids.

Quantitative Measurement of Carbon Dioxide Consumption of a Whole Paprika Plant (Capsicum annumm L.) Using a Large Sealed Chamber (대형 밀폐 챔버를 이용한 파프리카(Capsicum annumm L.) 개체의 이산화탄소 소비량 측정 및 정량화)

  • Shin, Jong-Hwa;Ahn, Tae-In;Son, Jung-Eek
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.211-216
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    • 2011
  • This study was carried out to clarify precise $CO_2$ demands of paprika plants (Capsicum annumm L.) by measuring photosynthesis rates of the leaves in high, low positions, and the $CO_2$ consumption of a whole plant in a large sealed chamber. A photosynthesis measuring system (LI-6400) was used to measure the photosynthetic rates of the leaves located in different positions. A large sealed chamber that can control inside environmental factors was developed for measuring $CO_2$ consumption by a whole paprika plant. With increase of radiation, photosynthetic rates of the leaves in higher position became larger than those in lower position. The $CO_2$ consumption by the plant was estimated by using decrement of $CO_2$ concentration from initial level of 1500 ${\mu}mol{\cdot}mol^{-1}$ in the chamber with increase of integrated radiation. A regression model for estimating $CO_2$ consumption by the plant (leaf area = 7,533.4 $cm^2$) was expressed with integrated radiation (x) and was suggested as $y=-0.06234+3.671^*x/(2.589+x)$ ($R^2=0.9966^{***}$). The photosynthetic rate of the whole plant measured in the chamber was 3.4 ${\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ under 300 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity, which is in-between photosynthetic rates of the leaves in high and low positions. For this reason, some differences between required and supplied $CO_2$ amounts in greenhouses might occur when depending too much on photosynthetic rates of leaves. Therefore, we can estimate more accurately $CO_2$ amount required in commercial greenhouses by using $CO_2$ consumption model of a whole plant obtained in this study in addition to leaf photosynthetic rate.

Evaluation on Cooling Effects of Geothermal Heat Pump System in Farrowing House (지열 냉방시스템을 이용한 분만돈사의 냉방효과 분석)

  • Choi, H.C.;Song, J.I.;Na, J.C.;Kim, M.J.;Bang, H.T.;Kang, H.G.;Park, S.B.;Chae, H.S.;Suh, O.S.;Yoo, Y.S.;Kim, T.W.;Park, J.H.
    • Journal of Animal Environmental Science
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    • v.16 no.2
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    • pp.99-108
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    • 2010
  • The principal objective of this study was to investigate the cooling effects of geothermal heat pump system (GHPS) in farrowing house. A total of 96 sows were allocated to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in summer season. During the experimental period of four weeks, the highest outside temperature observed was approximately $34.1^{\circ}C$, GHPS decrease indoor temperature of pig housing up to $30.9^{\circ}C$, but conventional pig housing was similar to outside temperature. Dust concentrations (maximum 61.4%) of particulate matter less than $10{\mu}m$ (PM 10) in GHPS-housing were lower than the conventional housing. GHPS showed no signigicant difference in carbon dioxide emission, whereas the ammonia gas concentration was significantly decreased in GHPS-housing compared to that of conventional housing. Sows in GHPS-housing showed significantly lower respiratory rate than those of the control group. GHPS did not affect hormone level, litter size and birth weight, but weaning weight of piglets was influenced by GHPS. Feed consumption of sows was significantly increased in GHPS-housing compared to the conventional hosing. These results suggest that GHPS decrease dust concentration, ammonia gas emission and indoor temperature of pig housing and may affect performance in sows and weaned piglets.

Comparison of Indoor CO2 Removal Capability of Five Foliage Plants by Photosynthesis (다섯가지 관엽식물의 광합성에 의한 실내 이산화탄소 제거능력 비교)

  • Park, Sin-Ae;Kim, Min-Gi;Yoo, Mung-Hwa;Oh, Myung-Min;Son, Ki-Cheol
    • Horticultural Science & Technology
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    • v.28 no.5
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    • pp.864-870
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    • 2010
  • This study was conducted to determine the effects of foliage plants on reducing indoor carbon dioxide ($CO_2$). Five foliage plants such as $Hedera$ $helix$ L., $Ficus$ $benjamina$ L., $Pachira$ $aquatica$, $Chamaedorea$ $elegans$, and $Ficus$ $elastica$ were selected and cultivated in two different growth medium (peatmoss and hydroball). Each plant was placed in an airtight chamber and then treated with the combinations of two different $CO_2$ concentrations (500 or 1,000 ppm) and two different light intensities (50 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). The change of $CO_2$ concentration (ppm) in the airtight chamber during day and night was measured and then converted into the photosynthetic rate (${\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$). As the results, each foliage plant reduced $CO_2$ level in the airtight chamber for one hour by photosynthesis. $Pachira$ $aquatica$ and $Ficus$ $elastica$ absorbed $CO_2$ more effectively compared to the other plants. The plants exposed to higher $CO_2$ concentration (1,000 ppm) and higher light intensity ($200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed more effective $CO_2$ elimination rate and photosynthetic rate. The plants that have wide leaves and big leaf areas such as $Pachira$ $aquatica$, $Hedera$ $helix$ L.,and $Ficus$ $elastica$ showed higher photosynthetic rate than the other plants that have smaller leaves. Released $CO_2$ concentration by respiration of the plants during the night was very low compared to the absorbed $CO_2$ concentration by photosynthesis during the day. There was no significant difference between peatmoss and hydroball medium on reducing $CO_2$ concentration and increasing photosynthetic rate. In conclusion, this study suggested that foliage plants can effectively eliminate indoor $CO_2$. Optimum environmental control in relation to photosyntheis and usage of right indoor foliage plants having lots of leaves and showing active photosynthesis even under low light intensity like indoor light condition would be required to increase the elimination capacity of indoor $CO_2$.

Evaluation of Design and Operation Parameters for a Spherical Sulfur Denitrification Reactor Treating High Strength Municipal Wastewater (고농도 도시하수 처리를 위한 입상황 탈질 반응조의 설계 및 운영인자 평가)

  • Kim, Yong-Hak;Chae, Kyu-Jung;Yim, Seong-Keun;Lee, Young-Man;Bae, Woo-Keun
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.12
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    • pp.1087-1093
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    • 2010
  • Autotrophic denitrification is known as an effective and economical alternative for heterotrophic denitrification using external carbon sources such as methanol. In this study, we evaluated design and operation parameters for a sulfur denitrification reactor (SDR) treating high strength nitrogen wastewater. The SDR was filled with spherical sulfur media in connected to a pilot-scale nutrient removal process (daily flow rate, $Q=18\;m^3/d$) using moving spongy media. Total nitrogen (TN) concentration of the final effluent was below the 7.0 mg TN/L because nitrate was additionally removed through autotrophic denitrificationin without adding alkalinity (initial alkalinity was $169.4{\pm}20.8\;mg$ $CaCO_3$/L). During the test period, 60~80% of nitrogen in the influent was removed even in low temperature (below $15^{\circ}C$). The alkalinity consumption for nitrate removal in SDR was $4.09{\pm}1.29$ g $CaCO_3/g$ ${NO_3}^-$-N, and the residual alkalinity of influent of SDR was higher than that of theoretical requirements for full conversion of nitrate. The consumption of sulfur was 943.8 g S/d and it was 2.4 times higher than theoretical value (400.1 g S/d) due to abrasion and loss of sulfur media in backwash, etc.

Photosynthetic Response of Foliage Plants Related to Light Intensity, $CO_2$ Concentration, and Growing Medium for the Improvement of Indoor Environment (실내 환경 개선을 위한 광도, 이산화탄소 농도 및 배지 종류에 따른 실내 관엽식물들의 광합성 반응)

  • Park, Sin-Ae;Kim, Min-Gi;Yoo, Mung-Hwa;Oh, Myung-Min;Son, Ki-Cheol
    • Protected Horticulture and Plant Factory
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    • v.19 no.4
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    • pp.203-209
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    • 2010
  • This study was performed to investigate photosynthetic responses of 4 foliage plants in relation to light intensity, carbon dioxide concentration, and media, and to select efficient plants for the indoor environment control based on the results. Four foliage plants used in this study included Syngonium podophyllum, Schefflera arboricola cv. Hong Kong, Dieffenbachia amoena, and Dracaena deremensis cv. Warneckii Compacta. The plants cultivated in two different growth media, peatmoss and hydroball, and subjected to various light intensities (0, 30, 50, 80, 100, 200, 400, and $600\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) and $CO_2$ levels (0, 50, 100, 200, 400, 700, 1000, and $1500\;{\mu}mol{CO_2}{\cdot}mol^{-1}$). As a result of the photosynthetic rate of foliage plants according to change of light intensity and $CO_2$ levels, Schefflera arboricola and Dieffenbachia amoena showed high apparent quantum yield, which stands for the photosynthetic rate under low light intensity, and both plants also recorded higher photosynthetic rate under high $CO_2$ concentration compared to the other two indoor plants. Dracaena deremensis showed the lowest photosynthetic rate under the low light intensity or high $CO_2$ concentration. There were inconsistent results in photosynthetic rate of foliage plants grown in peatmoss or hydroball. Higher photosynthetic rate was observed in Schefflera arboricola with peatmoss rather than hydroball as light and $CO_2$ concentration increased. However, hydroball had a positive effect on Dieffenbachia amoena in terms of photosynthetic rate. In case of Syngonium podophyllum, peatmoss induced higher photosynthetic rate according to increased light intensity, but there was no effect of media on the rate under various $CO_2$ treatements. In contrast, media did not affect to photosynthetic efficiency of Dracaena deremensis subjected to various light intensities and the rate of Dracaena deremensis with peatmoss was a little high when $CO_2$ concentration increased. In conclusion, potential plants for the indoor air pulification and environmental control were Schefflera arboricola and Dieffenbachia amoena because they showed high photosynthetic rate under typical indoor conditions, low light intensity and high $CO_2$ concentration.

Analysis of Terpenoids as Volatile Compound Released During the Drying Process of Cryptomeria japonica (삼나무 건조 중 발생하는 휘발성 유기화합물 Terpenoids의 분석)

  • Lee, Su-Yeon;Gwak, Ki-Seob;Kim, Seon-Hong;Lee, Jun-Jae;Yeo, Hwan-Myeong;Choi, In-Gyu
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.3
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    • pp.242-250
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    • 2010
  • The aim of this study was to investigate the terpenoids of Total Volatile Organic Compounds (VOCs) released during drying of Cryptomeria japonica using the thermal extractor (TE). Considering the drying process of C. japonica, temperatures of TE were set at $27^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$, and $120^{\circ}C$, respectively. As the result, the emission factors of VOCs and terpenoids were increased as temperature increased. The amount of terpenoids included in VOCs emission factors were 87.5%, 81.6%, 83.6%, 90.1%, and 97.3% depending on above temperatures, respectively. Especially at$100^{\circ}C$ and $120^{\circ}C$, the amount of terpenoids were measured more than 90%. ${\delta}$-cadinene was the highest yield at each temperature and 32 types of terpenoids were collected. Emitted terpenoids were classified into the sesquiterpene group which consists of 15 carbon sources. These 32 sesquiterpenes were used for determining the useful bioactivity such as antifungal activity by the agar dilution. As the result, they showed the antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum. The 5,000 ppm concentration of terpenoids showed a strong activity with 100% against the 3 fungi. At the 1,000 ppm concentration of terpenoids, the antifungal activities against three fungi were 95.2%, 98.7%, and 97.3%, and their activities were a little inhibited at 100 ppm concentration.

Enzymatic Hydrolysis of Rice Straw, a Lignocellulosic Biomass, by Extracellular Enzymes from Fomitopsis palustris (Fomitopsis palustris의 균체 외 효소에 의한 볏짚 당화에 관한 연구)

  • Kim, Yoon-Hee;Cho, Moon-Jung;Shin, Keum;Kim, Tae-Jong;Kim, Nam-Hun;Kim, Yeong-Suk
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.3
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    • pp.262-273
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    • 2010
  • In the enzymatic hydrolysis of rice straw and wood meals using extra-cellular enzymes from Fomitopsis palustris, key factors which enhanced the sugar conversion yield were investigated in this work, such as enzyme production and enzyme reaction conditions, surfactant effects, and the surface structure of substrates. F. palustris cultured with softwood mixture produced 12.0 U/$m{\ell}$ for endo-${\beta}$-1,4-gulcanase (EG), 116.68 U/$m{\ell}$ for ${\beta}$-glucosidase (BGL), 18.82 U/$m{\ell}$ for cellobiohydrolase (CBH), and 13.33 U/$m{\ell}$ for ${\beta}$-xylosidase (BXL). These levels of BGL, CBH, and BXL activities were two to four folds more than enzyme activities of F. palustris cultured with rice straw. The optimum reaction conditions of cellulase-RS which produced by F. palustris with rice straw and cellulase-SW which produced by F. palustris with softwood mixture were pH 5.0 at $45^{\circ}C$ and pH 5.0 at $50^{\circ}C$, respectively. The sugar conversion yield of cellulase-SW had the highest value of $40.6{\pm}0.6%$ within 72 h when rice straw was used as substrate. By adding 0.1% Tween 20 (w/w-substrate), the sugar conversion yield of rice straw was increased to 44%, which was about four fifths sugar conversion yield of commercial enzyme, Celluclast 1.5L (Novozyme A/S). A low crystallinity and an intensive fibril surface observed by the scanning electron microscope may explain the high sugar conversion yield of rice straw.