• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.41-47
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• 2000

This study was conducted to evaluate development of seed pellet technique such as pellet polymer search, the shape formation and hardness, the germination and emergence rate of the pellet seeds for labor-saving and reducing production cost in onion(Allium cepa L.) cultivation. The pellet seeds shape formation was good such as kaolin, clay, ash, and gypsum, and clay was good shape formation but surface of pellet seed was cracked during the drying. PG(pearlite + gypsum) as pellet material and PVA as binder were the best among the material in consideration with shape and hardness together. The hardness of the pellet seeds was affected by polymers, the kinds and concentration of binders, and that degree was large at polymer. The high hardness polymers were gypsum and coal ash, but burned lime was the lowest hardness among the pellet material. The germination(GP) and emergence percentage(EP) of pellet seed with PG in vitro were the highest among the material, and that was 93.6, 91.8%, respectively. The EP of pellet seed with PG at 20, $25^{\circ}C$ were 91.3, 92.0%, respectively, The EP of pellet seed were over the 91%, and those did not show difference with field moisture capacity , and that of 5 and 6mm size seed were the highest as 92%, respectively. and other size seeds showed over 90%, too. The EP of pellet seed with PG was decreasing as increasing the sowing depth, and that of at 10mm sowing depth was the highest as 92.7%. The time to 50% emergence of that under 70% field moisture capacity was 158h, and that was delayed at 20h compare to control seed.

• KSBB Journal
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• v.14 no.3
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• pp.337-341
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• 1999

In order to investigate effects of loess on the mycelial pellet formation a phosphate dissolving fungus, Penicillium sp. GL-101, was cultured in potato dextrose broth containing loess. The strain formed an amorphous pellet or loose aggregates agitated at a low speed(50rpm) while spherical and regular pellets at a high speed(150rpm). The higher concentration of loess, the smaller size of a pellet in the medium formed by the strain. Cultured in the medium supplemented with 1.5% loess the pellet size was reduced to a seventh compared to the control. In the case of addition of several insoluble salts, which are main components of loess, to the culture medium the higher concentrations of salts, the smaller sizes of pellet formed by the strain and the smallest pellet was formed by the addition of calcium sulfate.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.188-192
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• 1999

In order to minimize the mycelial pellet formation, one of the critical obstacles during the fermentation processes of filamentous fungi, an investigation was focused on the culture conditions(media and initial inoculum) and additives(soils, surfactants and polyethylene glycol 200) when a high phosphate-dissolving fungus, Penicillium sp. GL-101, was cultured in liquid media. Culturing the strain in PDB, SDB and YPD media, their pellet sizes decreased to the order of YPD > SDB > PDB. And at the high concentrations of the initial inoculum in the range from $1{\times}10^3\;to\;1{\times}10^6$ conidia/ml, the small sizes of pellet were formed in the PDB media. For the initial inoculum between $1{\times}10^7\;and\;1{\times}10^8$ conidia/ml, however, an amorphous pellet or loose aggregate was formed. The addition of soils, zeolite and diatomite, up to 1.0% decreased the pellet sizes to 3/4 and 1/2, respectively, but the pellet was increased to 2.5 times by the addition of bentonite. Surfactants also affected on the size of pellet; the addition of Triton X-100 and Tween 80 up to 1.0% decreased the pellet sizes maximally to 1/10 and 1/4, respectively, while SDS completely inhibited the fungal growth. Among the four additives tsted, polyethylene glycol 200 was the most effectively reduced the pellet sizes to $0.2{\pm}0.1$mm that resulted in about 25- fold reduction compared to the control.

• Journal of Power System Engineering
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• v.16 no.2
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• pp.36-42
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• 2012

본 논문은 고파워 전자소자로부터 에너지를 수확하는 열전생성기의 성능에 pellet의 기학학적 구조가 미치는 영향들을 보고한다. 열경계저항을 포함하는 열전모델을 적용하여, 다양한 경계조건들과 열원의 열율들에 대해 pellet의 높이, pellet의 단면적, thermocouple의 수를 최적화 하고, 이처럼 최적화된 pellet의 기하학적 구조를 갖는 열전생성기의 성능과 일반적인 pellet으로 구성된 열전생성기의 전력생성성능과 효율이 예측되고 비교되어진다. 예측된 결과는 최적화된 pellet으로 구성된 열전생성기가 일반적인 pellet으로 구성된 열전생성기보다 2-10배까지 생성효율이 우수함을 보여준다. 최적화된 pellet으로 구성된 열전생성기와 일반적인 pellet으로 구성된 열전생성기의 열적성능도 예측되고 비교된다.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.167-171
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• 2009

We conducted performance test of a 350 kW class wood pellet boiler installed at a dormitory whose total area is $1,354\;m^2$. The maximum heating capacity of the boiler is 350 kW(300,000 kcal/kg). The wood pellet boiler consists of 3 parts; boiler, hot water storage tank and wood pellet storage tank. In testing the boiler, we shut off hot water utility supply and open up floor heating water system in order to measure exact value of the heating output of the wood pellet boiler. To determine the efficiency and heating output of the wood pellet boiler, we measured mass flow rate of wood pellet, the lower heating value(LHV) of the wood pellet, mass flow rate and temperature of water for floor heating and so on. We measured the mass flow rate of fuel, wood pellet with respect to rotational speed of auger, wood pellet feeding screw. We also measured the flue gas concentration of the wood pellet boiler by using a gas analyser. The result shows that the efficiency of the wood pellet boiler is 80.6% based on lower heating value at 124 kW of heating output. At this condition, O2 concentration of the flue gas is 6.0%, CO and NOx concentrations are 85 and 102 ppm.

• Journal of the Korean Ceramic Society
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• v.36 no.8
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• pp.782-790
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• 1999

The compressibility sinterability sintering behaviour and thermal stability of AlOOH added UO2 pellt and PVA-Al(III) complex added UO2 pellet were investigated respectively. Compared with characteristics of AlOOH added UO2 pellet the green density and the sintered density of PVA-Al(III) complex added UO2 pellet were lowered but the grain size and the pore size of that were more increased in accordance with higher compacting pressure. The AlOOH added UO2 pellet had the grain size of about 14${\mu}{\textrm}{m}$ with monomodal pore size distribution while the PVA-Al(III) complex added UO2 pellet had the grain size of about 42 ${\mu}{\textrm}{m}$ with bimodal pore size distribution. The PVA-A(III) complex added UO2 pellet had a similiar open porosity to the AlOOH added UO2 pellet and a lower resintered density change than the AlOOH added UO2 pellet.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.818-826
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• 2017

In accordance with the New and Renewable Energy Supply Statistics, biomass power generation has surged since 2013, and use of wood pellet has the most sharply increased, 696Gwh in 2013, 2,764Gwh in 2014 and 2,512Gwh in 2015. Total domestic wood pellet consumption was 1.48million tons in 2015, of which wood pellets consumed for power generation account for about 1.08million tons, about 73%. In this study, we gained the result that the wood pellet would be consumed 2.61million tons in 2020, 6.85million tons in 2025, 11.39million tons in 2030. We also calculated the optimum biomass power generation, on the premise that the power plant co-fire 50% biomass, and the result was that 2.26million tons of wood pellets should be produced domestically in 2021 to operate the present licensed wood pellet power plant from this study.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.17-23
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• 2002

In order to investigate effects if loess on the mycellial pellet formation a phosphate-solubilizing fungus. Aspergillus sp. PS-104 was cultured in potato dextrose broth containing loess. The strain formed an amorphous pellet or loose aggregates agitated at a low speed (50 rpm) while spherical and regular pellets at a high speed (150 rpm) The higher concentration of loess was added, the smaller size of a pellet was formed during the submerged culture of the strain. As shown in results, being cultured in the PDB medium supplemented with 1.0% loess the pellet size was maximally reduced to a fourth compared to the control. Evaluating the addition effect of several components of loess such as $SiO_2$, $Fe_2O_3$, $Al_2O_3$, $CaCO_3$, $CaSO_4$ and $MgCO_3$ on the reduction of mycellial pellet size the higher concentration was supplied, the smaller size of pellet was formed except $Al_2O_3$. And the smallest pellet size was recorded at the concentration of 1.0% (W/V) magnesium carbonate.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.77-81
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• 2007

In order to minimize the mycelial pellet size of a high phosphate-solubilizing fungus, Aspergillus sp. PS-104 in liquid media, one of the critical obstacles during the submerged culture of filamentous fungi, an investigation was focused on the culture conditions (media and inoculum size) and additives (different soils, surfactants and polyethylene glycol 200). When the fungus was cultured in PDB, SDB and YPD media. their pellet sizes decreased in the order of SDB=YPD>PDB. At the higher concentrations of initial inoculum ranging from $1{\times}10^3$ to $1{\times}10^7$ conidia/ml, the smaller size of pellet was formed in the PDB medium. In addition, the pellet size was effectively reduced by 1/6${\sim}$1/4 by the addition of 0.1% soil containing zeolite, diatomite, loess, kaoline and talc, excluding bentonite. The addition of 0.1% Tween 80, Triton X-100 and PEG 200 also decreased the pellet size, but SDS completely inhibited the fungal growth.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.103.1-103.1
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• 2010

Recently domestic wood pellet boilers are installed in rural and forestry houses. The fuel price per lower heating value of wood pellet is about 20 % lower than that of heating oil on July 2010. In spite of lower price of wood pellet, a few user of wood pellet boiler complain expensive fuel cost. One of this reason is inaccurate or improper air-fuel ratio setting of wood pellet boiler. O2 concentration of flue gas of domestic wood pellet boiler is about 9.7 % and there are few domestic wood pellet boiler which can control air-fuel ratio automatically. We tested a domestic wood pellet boiler in changing boiler thermal output and air-fuel ratio. The nominal boiler thermal output is 25 kW (21 500 kcal/h). We measured thermal efficiency and flue gas concentrations such as CO and NOx at each boiler thermal load with various air-fuel ratio. The results show that if air flow rate is the same as full load and part load, thermal efficiency of part load of 40 % drops about 7.7 %p compared to boiler full load case.