• Transactions of the Korean hydrogen and new energy society
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• v.18 no.2
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• pp.197-206
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• 2007

There are several methods for the hydrogen production such as steam reforming of natural gas, photochemical method, biological method, electrolysis and thermochemical method, etc. Many researches have been widely performed for the hydrogen production method having low production cost and high efficiency. In this paper, the patents concerning the photochemical hydrogen production method were gathered and analyzed. The search range was limited in the open patents of USA(US), European Union(EP), Japan(JP), and Korea(KR) from 1996 to 2005. Patents were gathered by using key-words searching and filtered by filtering criteria. The patent application trend was analyzed by the years, countries, companies, and technologies.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.495-500
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• 2002

The purpose of this study is to develop and to apply this permanent cement mortar form as one of those system forms to improve existing form's problems. (1) In the fire proof test with combined specimen, the fire proof covering including form section thickness is satisfied with the fire proof criterion. It is considered that form section thickness has no problem (2) The suitable method of normal pressure steam curing for the form's mass production is 4 hours in 65℃ considering production cost, the silica fume admixture is economic.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.415-416
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• 2007

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1278-1279
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• 2006

New product line with additional secondary operation of oil pump rotor was built in necessity of increasing capacity. This new line includes steam treatment process after sizing. The new line achieved 1.6 times higher performance compared with a conventional line.

• Journal of Energy Engineering
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• v.19 no.4
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• pp.215-220
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• 2010

Hydrogen is a clean and efficient energy source and is expected to take an important role in future energy demand. A possibly good route to produce hydrogen is by using biomass and organic wastes as a source through thermo-chemical conversion technology. In this study, pyrolysis of wood Pellet(Oregon pine) has been carried out in batch type fixed-bed reactor in $N_2$ atmosphere during 20 minutes to determine the optimum hydrogen generating conditions. At the influence of temperature, hydrogen yield was increased with increasing temperature. For the influence of Steam/Biomass Ratio(SBR), hydrogen yield was increased by steam addition at low temperature condition. However, effect of steam addition was insignificant over at SBR = 1. The hydrogen yield was increased with increasing SBR at high temperature condition. From result of $H_2$/CO and $H_2/CH_4$ ratio, dominant reaction was steam reforming in this experimental condition. The optimum condition for hydrogen production was determined as follows: $H_2$ yield = 38.3 vol.% (56.01 L/min kg) at $900^{\circ}C$, SBR=3.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.62-68
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• 2006

High temperature electrolysis is a promising technology to produce massively hydrogen using renewable and nuclear energy. Solid oxide fuel cell materials are candidates as the components of steam electrolysers. However, the polarization characteristics of the typical electrode materials during the electrolysis have not been intensively investigated. In this study, NiO electrode was deposited on YSZ electrolyte by spin coat process and firing at $1300^{\circ}C$. Pt electrode was applied on the other side of the electrolyte to compare the polarization characteristics with those by NiO during electrolysis. The $H_2$ evolution rate was also monitored by measuring the electromotive force of Lambda probe and calculated by thermodynamic consideration. At low current density, Pt showed lower cathodic polarization and thus higher current efficiency than Ni, but the oxidation of Ni into NiO caused the increase of anodic resistance with increasing current density. High overpotential induced high power consumption to produce hydrogen by electrolysis.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.6
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• pp.500-506
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• 2010

The metal monolith catalyst coated with 15wt% Ni/$MgAl_2O_4$ is applied to the natural gas steam reforming for hydrogen production. To address the improvement of adherence between metal monolith and catalyst coating layer, the pre-calcination temperature as well as the coating conditions of $Al_2O_3$ sol are optimized. When the Fe-Cr alloy monolith is pre-calcined at $900^{\circ}C$ for 6 h, $Al_2O_3$ layer was formed uniformly on the entire surface of the metal substrate. It is seen that the formation of $Al_2O_3$ layer on the monolith surface is essential for the uniform coating of $Al_2O_3$ sol onto the monolith substrate. The monolith catalyst coated with 10wt% $Al_2O_3$ sol shows high $CH_4$ conversion and good thermal stability as compared with the monolith catalyst without $Al_2O_3$ sol coating under severe reaction conditions with high GHSV of 30,000 $h^{-1}$ at $700^{\circ}C$. In addition, the metal monolith catalyst shows higher catalytic activity and better thermal conductivity than 15wt% Ni/$MgAl_2O_4$ pellet catalyst.

• Applied Chemistry for Engineering
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• v.2 no.1
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• pp.30-37
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• 1991

The production of hydrogen from steam by reduced iron with additives such as CuO, $In_2O_3$, $MoO_3$ and $WO_3$ has been kinetically investigated. It was shown that all additives have a promoting effect on reaction activity in the order of $$MoO_3{\gg}In_2O_3{\sim_=}WO_3{\sim_=}CuO$$. The shrinking core model was applied to predict the complete conversion time and the results were quite comparable with experimental values. The reaction was carried out in a fixed flow reactor packed with reduced iron with 1 wt % of additives under the conditions, $600-750^{\circ}C$, Ar flow rate of 1 L/min and steam partial pressure of 0.085 atm. The apparent activation energies were 14.2, 20.9, 21.3, 22.4 and 27.9 kJ/mol with $MoO_3$, $In_2O_3$, $WO_3$, CuO and without additive, respectively.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.351-356
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• 1986

The effects of drum spacing, steam pressure and drum speed on drying rate of minced fish flesh on both single and double drum dryers were studied. Starch additions in the form of tapioca flour up to 2.5% have been found satisfactory for aiding in sheet formation at the doctor blade. When the retention time was adjusted to maintain a constant product moisture, the highest production rate was obtained at the smallest drum spacing and the highest steam pressure within the limits of experimental conditions considered. The operating conditions suitable for producing the flakes with 5% moisture were: 100 kPa (steam pressure), 0.1 mm (drum spacing) and 3 rpm (drum speed). The production rate and overall heat transfer coefficient under these conditions were $12.1\;kg/m^2$hr and 950 $W\;/m^2K$ respectively. The drying data were fitted well to the conventional drying model, namely $MR\;=\;A\;\exp\;(-k{\theta})$, resulting in the various drying constants depending the operating conditions.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.683-688
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• 1991

Wheat flour was extruded by a single-screw extruder, and used for the ethanol production of takju. The molecular structure and enzymic susceptability of extruded starch were compared to those of steam cooked one. The gel permeation chromatographic pattern of wheat flour extrudates was not significantly different from those of raw and steam cooked starches. However, the conversion rate of extruded starch into maltose by ${\alpha}-amylase$ hydrolysis was significantly faster than those of raw ad steamed starch. The molecular weight of starch estimated from GPC pattern and the intrinsic viscosity were remarkably reduced by extrusion cooking followed by the enzymic hydrolysis for 30 min, while steam cooking and enzymic hydrolysis for 30 min did not change them significantly. Extrusion-cooked flour produced alcohol 26% higher than that of steamed flour in the laboratory takju fermentation, and 10% more alcohol in the pilot plant scale takju production.