• Asian-Australasian Journal of Animal Sciences
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• 제12권5호
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• pp.747-751
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• 1999

The Hohenheim in vitro gas test was used to assess the nutritional value of some crop residues of known in vivo digestibility. The crop residues are groundnut shells (GNS) corn cobs (CC); cassava peels (CaP); unripe and ripe plantain peels (UPP, RPP) and citrus pulp/peels (CPP). Compared to other crop residues, crude protein (CP) content of CC was low. Except for CaP and CPP that had low neutral detergent fibre (NDF) and acid detergent fibre (ADF), other residues contained a high amount of cell wall constituents. Net gas production was significantly different among the crop residues (p<0.05). Gas production was highest in CPP followed by CaP. CC, UPP and RPP have the same volume of net gas production, while the least net gas production was in GNS. True dry matter (TDM) digestibility was significantly different (p<0.05) among the residues. GNS was the least in TDM digestibility. CaP, UPP and RPP had similar TDM digestibility values, while the highest TDM digestibility was obtained in CPP. OM digestibility was different among the residues (p<0.05). CaP and CPP had the same ME value while CC, UPP and RPP had close ME values and GNS the least in ME (p<0.05). The potential extent (b) and rate (c) of gas production were statistical different among the residues (p<0.05). The Hohenheim gas test gave high in vitro organic matter (OM) digestibility for CC, CaP, UPP and RPP and CPP. Fermentable carbohydrates and probably available nitrogen in the crop residues influenced net gas production. The results showed that crop residues besides, providing bulk are also a source of energy and fermentable products which could be used in ruminant livestock production in the tropics.

• 한국작물학회지
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• 제34권s01호
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• pp.33-39
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• 1989

Ethylene gas classified as one of five major plant hormones plays an important role in various plant metabolism. The precise analysis of ethylene production of plants or plant parts is a valuable research procedure because knowledge of ethylene production facilitates measures of the physiological activity within the tissue. This paper describes procedures for analyzing ethylene from plant tissues by gas chromatography and discusses problems associated with extracting gas samples either by introducing a vacuum to plant samples or by using a hypodermic syringe. Introduced are a continuous flow system for efficient analysis and an automated system for sampling, analyzing, calculating and recording ethylene production data.

• 한국수소및신에너지학회논문집
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• 제17권2호
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• pp.218-226
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• 2006

It can be obtained from hydrocarbon and water, specially production of hydrogen from natural gas is most commercial and economical process among the hydrogen production methods, and has been used widely. However, conventional hydrogen production methods are dependent on fossil fuel such as natural gas and coal, and it may be faced with problems such as exhaustion of fossil fuels, production of greenhouse gas and increase of feedstock price. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases. However, nuclear hydrogen must be economical comparing with conventional hydrogen production method. Therefore, hydrogen production cost was analyzed and estimated for nuclear hydrogen as well as conventional hydrogen production such as natural gas reforming and coal gasification in various range.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1084-1093
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• 2000

An in vitro gas production system was used to investigate the influence of various substrate mixtures on a natural mix of rumen microbes by measurement of fermentation end-products. The treatments were combinations of cassava (15.0, 30.0 and 45.0%) with different roughage sources (ruzi grass, rice straw or urea treated rice straw). Microbial biomass, net $^{15}N$ incorporation into cells, volatile fatty acid production, gas volume and rate of gas production increased linearly with increasing levels of cassava inclusion. There was also an effect of roughage source, with rice straw being associated with the lowest values for most parameters whilst similar values were obtained for ruzi grass and urea treated rice straw. The results suggest that microbial growth and fermentation rate increase as a function of readily available carbohydrate in the substrate mixture. A strong linear relationship between $^{15}N$ enrichment, total volatile fatty acid production and gas production kinetics support the suggestion of the use of the in vitro gas production system as a tool for screening feedstuffs as an initial stage of feed evaluation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.519-523
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• 2007

Gas(or methane) hydrates are solid solutions when water molecules are linked through hydrogen bonding and create host lattice cavities that can enclose a large variety of guest gas molecules. The natural gas hydrate crystal may exist at low temperature above the normal freezing point of water and high pressure greater than about 30 bars. A lot of quantities of natural gas hydrates exists in the earth and many production schemes are being studied. In the present investigation, depressurization method was considered to predict the production of gas and the simulation of the two phase flow - gas and water - in porous media is being carried out. The simulation show about the fluid flow in porous media have a variety of applications in industry. Results provide the appearance of gas and water production, the pressure profile, the saturation of gas/ water/ hydrates profiles and the location of the pressure front.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.196-199
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• 2008

In this study, gas hydrate production has been followed using swapping method to investigate the effect of injection rate of flue gas and soaking period in unconsolidated artificial sand sample. The results shows that recovery factor of methane gas decreases with increasing the injection rate of flue gas. This indicates that the velocity of flue gas in porous media may act as kinds of inhibitor for production of hydrate. Also recovery factor increases with increasing the soaking time.

• Ocean Systems Engineering
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• 제2권1호
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• pp.49-68
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• 2012

In this paper, an offshore process front end engineering design (FEED) method is systematically introduced and reviewed to enable efficient offshore oil and gas production plant engineering. An integrated process engineering environment is also presented for the topside systems of a liquefied natural gas floating production, storage, and offloading (LNG FPSO) unit, based on the concepts and procedures for the process FEED of general offshore production plants. Various activities of the general process FEED scheme are first summarized, and then the offshore process FEED method, which is applicable to all types of offshore oil and gas production plants, is presented. The integrated process engineering environment is presented according to the aforementioned FEED method. Finally, the offshore process FEED method is applied to the topside systems of an LNG FPSO in order to verify the validity and applicability of the FEED method.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.643-647
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• 2004

An in vitro experiment was carried out to investigate effects of solid associated (SAB) and liquid associated bacteria (LAB) and the type of incubation substrate on ruminal fermentation and gas production profiles. Bacterial fraction did not influence total numbers of bacteria. Gas production degradation parameters were significantly influenced by bacterial fraction and type of substrate (p<0.05). There was significant interaction between bacterial fraction and type of substrate in gas production (p<0.01). Total VFA concentration and acetic and propionic acid ratio were also influenced by bacterial fraction and type of substrate with little differences in individual VFA concentration.

• 한국환경보건학회지
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• 제16권2호
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• pp.89-95
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• 1990

This study was investigated to the energy recovery by the pyrolysis of waste tyre. the pyrolysis of the waste tyre was made by using the pyrolysis chamber for the gasification and the combustion chamber for the combustion of the pyrolysis gas. In batch system, the amount of waste tyre was put 150kg in the pyrolysis chamber and the proper air flow rate for the stable production of the pyrolysis gas was 0.95Nm$^{3}$ /min. the production time of the pyrolysis gas was stable above 210minutes, and the stable production rate was above 3.8Nm$^{3}$ /min. The production temperature of pyrolysis gas was 170$^{\circ}$C and combustion temperature of pyrolysis gas was 1,000$^{\circ}$C. The combustible component of washing gas in pyrolysis gas of waste tyre was CO, CH$_{4}$, $C_{2}H_{6}$ and $C_{3}H_{8}$, and total amount was 22.7%. Heat value of condensed material was 9,804Kcal/kg. The average concentration of air pollutants between cyclone and scrubber was CO 420.4ppm, SO$_{x}$ 349.8ppm. NO$_{x}$ 68.Sppm, HCl 24.4ppm and Dust 240.0g / Nm$^{3}$, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.188-191
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• 2008

There have been many methods for producing natural gas from gas hydrate reservoirs in permafrost and sea floor sediments. It is well knownthat the depressurization should be a best option for Class 1 gas hydrate deposit, which is composed of tow layers: hydrate bearing layer and an underlying free gas. However many of gas hydrate reservoirs in sea floor sediments are classified as Class 2 that is composed of gas hydrate layer and mobile water, and Class 3 that is a single gas hydrate layer. The most appropriate production methods among the present methods such as thermal stimulation, inhibitor injection, and controlled oxidation are still under development with considering the gas hydrate reservoir characteristics. In East Sea of Korea, it is presumed that the thick fractured shale deposits could be Class 2 or 3, which is similar to the gas hydrate discovered offshore India. Therefore it is needed to evaluate the possible production methods for economic production of natural gas from gas hydrate reservoir. Here we would like to present the production of natural gas from gas hydrate deposit in East Sea with industrial flue gases from steel company, refineries, and other sources. The existing industrial complex in Gyeongbuk province is not far from gas hydrate reservoir of East Sea, thus the carbon dioxide in flue gas could be used to replace methane in gas hydrate. This approach is attractive due to the suggestion of natural gas productionby use of industrial flue gas, which contribute to the reduction of carbon dioxide emission in industrial complex. As a feasibility study, we did the NMR experiments to study the replacement reaction of carbon dioxide with methane in gas hydrate cages. The in-situ NMR measurement suggeststhat 42% of methane in hydrate cages have been replaced by carbon dioxide and nitrogen in preliminary test. Further studies are presented to evaluate the replacement ratio of methane hydrate at corresponding flue gas concentration.