• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.335-350
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• 2013

With the efforts to development of renewable energy technologies, and increasing awareness to environmental issues, the usage of wood pallets has been increasing every year since the introduction of wood pallet technology to the domestic market. until 2009, majority usage of pellet boiler was in the residential houses. In an effort to increase the distribution of wood pellet boiler to cultivation facilities with high usage of fuels, The Ministry of Agriculture and Forestry has launched a distribution project of wood pellet boiler for fuel usage as a part of the agricultural and fishery energy efficiency projects. Although only small number of farms with a heat-culturing facility have replaced from conventional boiler to pellet boiler. Although part of reason for low usage of pallet boiler is lack of understanding and information of it, the main reasons are high initial cost and uncertainty of its cost efficiency. Also, most people from agricultural industry don't realize it's significance in terms of environmental benefit due to lack of understanding in 'resource circulation' and 'adopting to climate change'. In this study, first, we did a cost-efficiency analysis of the farm which uses a diesel boiler to grow cucumber, tomato, paprika. Then we replaced the diesel boiler to a pallet boiler and measured its cost-efficiency again. By comparing the cost-efficiency of the diesel boiler with the pellet boiler, we analyzed the economic viability of pellet boiler. Then we analyzed viability of pallet boiler usage in terms of 'resource circulation' and 'adopting to climate change'. As a result of our analysis, we have found out that under the current system of government support, the energy usage varies depends of the types crops grown and the higher the energy use, the more cost efficient it is to use the pallet boiler. Also, it is economically viable to use the pallet boiler in terms of 'resource circulation' and 'adopting to climate change'.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.99-106
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• 2016

Our aim was to identify the potential of reed stalk as a raw materials for biomass pellet production. Compared to woody biomass, reed stalk contained significant levels of ash. The holocellulose content of reed stalk was similar to that of larch, but the lignin content of reed stalk was lower than that of larch. In the elemental analysis, chlorine content of reed stalk was much higher than that of larch, and satisfied only the mixed biomass pellet B of European non-woody pellet standards(EN 14961-6). In quantitative analysis of the ash, heavy metals contents of reed stalk satisfied European non-woody pellet standards. Higher heating value of oven-dried reed stalk pellet was slightly lower than that of larch wood pellet. The durability of reed stalk pellet was lower than that of larch wood pellet. The results of this study indicate that reed stalk might be used as a raw material of mixed biomass pellet B.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.439-449
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• 2014

RPS (Renewable Portfolio Standard) has increased wood pellet demand dramatically in recent years in Korea where self-supply rate of wood pellet is not more than 10%. However global production capacity of wood pellet is prospected to be unable to meet the global demand after 2020. Therefore it is urgently needed to develop new sustainable biomass energy resources which can replace wood pellet at lower cost. As a result of this study EFB (empty fruit bunch) and MF (mesocarp fiber), the representative solid palm biomass, are estimated to be generated at the rate of 20 and 28 million tons per year (based on 10% moisture content) in Malaysia and Indonesia, respectively in 2012. Total annual generation rate of EFB and MF is estimated as 48 million tons per year only in Malaysia and Indonesia in 2012. With calorific value of over 90% of wood pellet EFB is expected to be a excellent biomass energy resource which can replace wood pellet. EFB can be utilized as fuel for power generation or industrial purpose. However EFB may not be a proper fuel for domestic and greenhouse heating because of its high ash content.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.252.2-252.2
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• 2010

Biomass is considered to be a major potential fuel and renewable resource for the future. In fact, there is high potential to produce the large amount of energy from biomass around the world. In this study, to obtain basic data for practical application of wood pellet and wood pellet boiler system as heating system in agriculture, agricultural biomass resources were surveyed, pellet was made of agricultural by-product such as stem of rape, oat and rice, ricehusk and sawdust and wood pellet boiler system with capacity of 116 kW was manufactured and installed in greenhouse of $38.5m{\times}32m$. High heating value, bulk density and ash content of pellet made of agricultural by-product and efficiency and heating performance of this system was estimated. Rice straw was the largest agricultural biomass in 2005 and the total amount of rice straw converted into energy of $131.71{\times}10^{11}$ kJ. And in 2005, total amount of forest' by-product converted into energy of $29,277.05{\times}10^{11}$ kJ. High heating values of pellets made of agricultural by-products of stem and seed of rape, stem of oat, rice straw and rice husk were 16,034, 16,026, 16,089, 15,650, 15,044 kJ/kg respectively. High heating values of pellets made of agricultural by-products were 83.6% compared to that of wood pellet. Average bulk density of pellets made of agricultural by-products of stem and seed of rape, stem of oat, rice straw and rice husk was 1,400 $kg/m^3$. Ash contents of the pellets were 6.6, 7.0, 6.2, 5.5, 33% respectively. Ash content of rice husk pellet was the largest compared to other kind of pellets. To increase efficiency of agricultural pellet boiler, the boiler adopted secondary heat exchanger. The agricultural pellet boiler designed and manufactured in this study had high efficiency of 84.2% compared to the conventional agricultural pellet boiler, when water flow rate, exhaust gas temperature and average combustion furnace temperature were 39L/min, $180^{\circ}C$, $680^{\circ}C$ respectively. And pellet supplying and pausing time were 13, 43 seconds respectively. In March of 2010, prices of wood pellet, agricultural tax free diesel, diesel, kerosene were 350 won/kg, 811 won/L, 1,422 won/L, 976 Won/L respectively. Also in terms of energy, prices per same heating value were 77.8, 90.1, 158, 108.4 Won/Mcal. Energy saving rate of wood pellet was 16, 50, 39% compared to agricultural tax free diesel, diesel and kerosene respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.104.1-104.1
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• 2010

We investigated combustion characteristics of wood pellets in a combustion equipment with adjusting amount of flue gas. Maximum temperature in a combustion chamber was $850^{\circ}C$. Higher heating Value of a domestic wood pellet tested is 19.1 MJ/kg and water content was 8.3%. Amount of flue gas causes big effect on burning characteristics in $450{\sim}600^{\circ}C$. Wood pellet does not burn in low temperature atmosphere less than $450^{\circ}C$ and low flue gas flow rate. We made burning the pellet that is made in Korea, USA, Chile and Canada. Color of foreign pellets are bright brown and they made by mainly sawdust. Korean pellet is a dark brown color because it contains bark. There are some differences in the result of elementary analysis and technical analysis. According to the result of burning experiment, burning times of each countries's pellet are similar.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.318-326
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• 2014

This study was conducted to investigate the potential of non-used forest biomass residues as raw materials for making wood pellets with additives such as wood tar and starch and to evaluate fuel characteristics of the pellets. Wood tar, a by-product provided from the carbonization process of wood, could be a suitable additive for wood pellet production due to its higher calorific value and lower hazardous heavy metals, such as cadmium and mercury, compared to woody biomass. When the wood tar (10 wt%) was added, the calorific value was increased from 4,630 kcal/kg (wood pellet without additive) to 4,800 kcal/kg (wood pellet with additive). With the increase of additive amount into wood pellet, the length and individual density of wood pellet increased. In addition, bulk density of the pellets was increased, whereas the fine content was decreased. Consequently the overall productivity of wood pellets was improved by adding 2 w% additives into wood pellets; the percentage of productivity increase was 5.9% and 4.9% for adding starch and wood tar, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.221-224
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• 2008

We made densified wood pellet by hemp woody core as replacing wood resource. Hemp was separated into the bast fiber and the woody core by hot steaming treatment. The hemp woody core had a similar lignin content and carbohydrate composition with hardwood. Also, the hemp had a low ash content, which resulted in a low ash formation in pellet burning. Heating value of the hemp pellet had a very similar to the pellet made by hardwoods. The hemp woody core can replace hardwood for densified wood pelletmaking.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.305-319
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• 2013

In this study, it is intended that utilize the LCA (Life Cycle Assessment) method, to evaluate the environmental impact of wood pellet manufacturing facility. As mentioned above, wood pellet manufacturing facility of 20 has produced wood pellets as a raw material sawdust and wood in our country. In this study, in order to feature manufacturing process of wood pellets that resemble almost necessary to analyze evenly size and characteristics of various equipment whether these reasonable, the characteristics of the equipment may be different, the production of 20 places I surveyed the facility one central timber distribution center one large scale most of the equipment.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.703-719
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• 2017

Miscanthus had a higher lignin content (19.5 wt%) and carbohydrate (67.6 wt%) than other herbaceous crops, resulting in higher pellet strength and positive effect on combustion. However, miscanthus also contains a high amount of hydrophobic waxes on its outer surface, cuticula, which limits the pellet quality. The glass transition of lignin and cuticula were related to forming inter-particle bonding, which determined mechanical properties of pellet. To determine the effects of surface waxes, both on the pelletizing process and the pellet strength were compared with raw and extracted samples through solvent extraction. In addition, to clarify the relationship between pellet process parameters and bonding mechanisms, the particle size and temperature are varied while maintaining the moisture content of the materials and the die pressure at constant values. Furthermore, kraft lignin was employed to determine the effect of kraft lignin as an additive in the pellets. As results, the removal of cuticula through ethanol extractions improved the mechanical properties of the pellet by the formation of strong inter-particle interactions. Interestingly, the presence of lignin in miscanthus improves its mechanical properties and decreases friction against the inner die at temperatures above the glass transition temperature ($T_g$) of lignin. Consequently, it could found that the use of kraft lignin as an additive in pellet reduced friction in the inner die upon reaching its glass transition temperature.

• Korean Journal of Plant Resources
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• v.22 no.4
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• pp.293-298
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• 2009

We prepared densified wood pellet by agricultural waste. The hemp woody core was used as replacing wood resource. Hemp was separated into the bast fiber and the woody core by hot steaming treatment. The hemp woody core had a similar lignin content(19.4%) and carbohydrate composition with hardwood(20-25% lignin in hardwood), respectively. Also, the hemp had a low ash content(0.5%), which resulted in a low ash formation in pellet burning. Heating value of the hemp pellet(18.40 MJ/kg) had a very similar to the pellet made by hardwoods. The hemp woody core could be replaced the hardwood for densified wood pellet.