• Transactions of the Korean hydrogen and new energy society
• /
• v.27 no.6
• /
• pp.702-711
• /
• 2016

The authors reviewed information about biorefining of biomass by using academic information databases. Feedstocks were classified into triglycerides biomass, sugar biomass, starchy biomass, lignocellulosic biomass, and organic waste biomass. Biorefinery is an integrated system converting biomass into biofuels and biochemicals by various physical, chemical, biological, and thermochemical technologies. This paper presented a comprehensive summaries of opportunities, recent trends and challenges of biorefinery. A brief overview of promising building blocks, their sources from biomass, and their derivatives were also provided. In conclusion, this paper demonstrated the feasibility of biorefinery producing biofuels and biochemicals from biomass.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.46 no.3
• /
• pp.85-92
• /
• 2004

Biomass is considered to be a major potential fuel and renewable resource for the future. In fact, there is high potential to produce significant amount of energy from biomass around the world. In spite of the potential, there are a few efforts in biomass utilization in this nation. In this study, elemental biomass data was obtained with respect to the amount and calorific values of agricultural residues. Rice straw and husks were not included in the evaluation due to their demand from alternative uses such as livestock feedings, bedding materials, and so forth. Dry basis high calorific values are about 4,500 kcal/kg for all the agricultural residues investigated, similar to literature data. Energy densities or unit area energy value, from pepper and sesame were significant and comparable to those of woody biomass. These elemental data for biomass resources will Provide the background of Planning and development of biomass energy Program, which is getting more feasible along with advances in energy conversion technologies such as micro gas turbines.

• Journal of Forest and Environmental Science
• /
• v.36 no.1
• /
• pp.17-24
• /
• 2020

This study aimed to figure out and compare the increment of biomass by thinning intensity focused on the plantation of the two major coniferous species (Larix kaempferi and Pinus koraiensis) of South Korea. The inventory interval was three years under the effects of three types of thinning treatments; control (no thinning), light (20% thinning) and heavy (40% thinning). The results showed standing biomass increment of both species decreased as thinning intensity increased (heavylight>control). Meanwhile, the lowest of on-site biomass changes occurred in the control plot, and the greatest was in the heavy thinning plot because thinning was involved with leaving the felling residual biomass (leaves, branches and roots) on the site. According to the results from this short-term study, unthinned stands is preferable for maximizing standing biomass as well as carbon sequestration. However long-term investigation should be considered in order to see more clear results.

• Journal of Ecology and Environment
• /
• v.29 no.2
• /
• pp.151-155
• /
• 2006

Root nodule biomass, and seedling biomass and growth were examined for 2-year-old Robinia pseudoacacia and Amorpha fruticosa seedlings following fertilization treatments. Organic fertilizer, solid combination fertilizer, and organic fertilizer plus solid combination fertilizer were used for the study. Root nodule biomass (g/plant) ranged from 3.00 to 7.06 for R. pseudoacacia and varied from 1.52 to 2.32 for A. fruticosa, respectively. In all treatments, root nodule biomass of R. pseudoacacia was significantly higher than those of A. fruticosa. Fertilization significantly increased root nodule biomass for only R. pseudoacacia, however, there were no significant differences in root nodule biomass among fertilization treatments. Root nodule biomass was not influenced by soil nitrogen (N) and phosphorous (P) concentrations following fertilization treatments. Seedling biomass (components and total) and growth (diameter at root collar and height) were strongly correlated with root nodule biomass for the two N fixing tree species.

• Journal of Korean Society of Forest Science
• /
• v.99 no.5
• /
• pp.726-735
• /
• 2010

Publications with the data on allometric equation, biomass and productivity of major oak forests in Korea were reviewed. Different allometric equations of major oak species showed site- or speciesspecific dependences. The biomass of major oak forests varied with age, dominant species, and location. Aboveground tree biomass over the different oak species was expressed as a power equation of the stand age. The proportion of tree component (stem, branch and leaf) to total aboveground biomass differed among oak species, however, biomass ranked stem > branch > leaf in general. The leaf biomass allocation over the different oak species was expressed as a power equation of total aboveground biomass while there were no significant patterns of biomass allocation from stem and branch to the aboveground biomass. Tree root biomass continuously increased with the aboveground biomass for the major oak forests. The relationship between the root to shoot ratio and the aboveground tree biomass was expressed by a logarithmic equation for major oak forests in Korea. Thirteen sets of data were used for estimating the net primary production (NPP) and net ecosystem production (NEP) of oak forests. The mean NPP and NEP across different oak forests was 10.2 and 1.9 Mg C $ha^{-1}year^{-1}$. The results in biomass allocation, NPP and NEP generally make Korean oak forests an important carbon sinks.

• Ocean and Polar Research
• /
• v.33 no.2
• /
• pp.135-147
• /
• 2011

Zooplankton is an important constituent in assessing ecosystem responses to global warming. The northern East China Sea is an important ecosystem for carbon cycling with a net sink of carbon dioxide. Despite their importance as a major component in carbon cycling, relatively little is known about zooplankton biomass structure and its regulating factors in the northern East China Sea. This study examined zooplankton biomass distribution pattern in the region from multiple cruises encompassing various seasons between 2004 and 2009. Results showed that zooplankton biomass exhibits less cross-shelf gradient in general with declining biomass to the eastern shelf towards the Tsushima Current Water. Size-fractionated biomass showed that the 1.0~2.0 mm size group, mostly copepods, dominated zooplankton biomass, comprising 38 to 48% of total biomass. Smaller zooplankton (0.2~1.0 mm) biomass, consisting mainly of Paracalanus spp, a particle eating herbivorous copepod, was positively related to chlorophyll-a concentration, but no relationship was established for larger zooplankton (1.0~5.0 mm). Spatially-averaged mean total zooplankton biomass was also highly related to chlorophyll-a concentration. These result suggest that the long-term trend of zooplankton biomass increase in this region is partly accounted for by the increases of phytoplankton biomass and productivity underway in the region. However, the underlying mechanisms of how sea surface warming in the study area leads to increased phytoplankton biomass and productivity remains unclear.

• KEPCO Journal on Electric Power and Energy
• /
• v.2 no.4
• /
• pp.525-529
• /
• 2016

Biomass co-firing to existing thermal power plants is one of the most economical and efficient way to reduce $CO_2$ emission from the plant. There are several methods of co-firing and it can be categorized into (1) Parallel co-firing, (2) Indirect co-firing, and (3) Direct co-firing. Parallel co-firing is the most expensive way to high-ratio co-firing because it requires biomass dedicated boiler. Direct co-firing is widely used because it does not need high capital cost compared with the other two methods. Regarding the direct co-firing, it can be classified into three methods- Method 1 does not need retrofit of the facilities because it uses existing coal mills for pulverizing biomass fuels. In this case high-ratio co-firing cannot be achieved because of poor grindability of biomass fuels. Method 2 needs biomass-dedicated mills and revision of fuel streams for the combustion system, and Method 3 needs additional retrofit of the boiler as well as biomass mills. It can achieve highest share of the biomass co-firing compared with other two methods. In Korea, many coal power plants have been adopting Method 1 for coping with RPS(Renewable portfolio standards). Higher co-firing ratio (> 5% thermal share) has not been considered in Korean power plants due to policy of limitation in biomass co-firing for securing REC(Renewable Energy Certificate). On the other hand, higher-share co-firing of biomass is widely used in Europe and US using biomass dedicated mills, following their policy to enhance utilization of renewable energy in those countries. Technical problems which can be caused by increasing share of the biomass in coal power plants are summarized and discussed in this report. $CO_2$ abatement will become more and more critical issues for coal power plants since Paris agreement(2015) and demand of higher share of biomass in the coal power plants will be rapidly increased in Korea as well. Torrefaction of the biomass can be one of the best options because torrefied biomass has higher heating value and grindability than other biomass fuels. Perspective of the biomass torrefaction for co-firing is discussed, and economic feasibility of biomass torrefaction will be crucial for implementation of this technology.

• Korean Journal of Soil Science and Fertilizer
• /
• v.37 no.2
• /
• pp.109-115
• /
• 2004

To elucidate the effects of composted pig manure on soil biochemical properties, composted pig manure was amended in a sandy loam soil and Chinese cabbage was grown. Composted pig manure treatments included 8, 29 and $57Mg\;ha^{-1}$ for CM-08, CM-29, and CM-57 plots, respectively. Biomass contents and enzymes activities in the non-rhizophere soil were measured. Activities of protease, phosphomonoesterase and dehydrogenase in the plot CM-57 increased to 2.3, 1.6, and 2.4 fold as compared with those of the control plot. Soil microbial biomass contents increased in proportion to the application rates of compost and biomass C, N, and P in the plot CM-59 were 4.3, 3.4, 2.8-fold higher than those of control p1ot(no fertilizer), respectively. During cultivation of Chinese cabbage, biomass C and N were higher in the middle growth stage, although biomass P was the highest in the early growth stage. The average ratio of biomass C:N:P was 11:2:1, and proportion of biomass C and N in the soil organic C and N was 1.1 and 3.6%, respectively. Activities of protease and dehydrogenase had significant correlations with biomass C and P.

• Journal of Korea Foresty Energy
• /
• v.18 no.1
• /
• pp.11-16
• /
• 1999

Dry weights of leaves, stem and floral organs of 15-year-old Tilia amurensis RUPR., were measured twice on 1 June and 20 August 1995 to examine the difference in biomass production between the reproductive and vegetative twigs which are morphologically neighboring and alternative. The following results were obtained : (1) The biomass of the reproductive twigs was greater than that of the vegetative twigs in both June and August. (2) The ratio of stem to total biomass in the reproductive and the vegetative twigs was greater in August than that in June, while the ratio of leaf biomass was greater in June than that in August. The ratio of floral organ to the total biomass in the reproductive twigs was 14.6% and 27.1% in June and August, respectively. (3) The total twig biomass per leaf biomass was greater in the reproductive twigs than that in the vegetative twigs in both June and August. (4) Net assimilation rate in the floral organs showed 21% of that in the leaves in June and 37% in August.

• Journal of Electrochemical Science and Technology
• /
• v.9 no.2
• /
• pp.157-162
• /
• 2018

In the study, herbaceous biomass waste including giant miscanthus, corn stalk, and wheat stalk were used to prepare commercially valuable activated carbons by KOH activation. The waste biomass predominantly consists of cellulose/hemicellulose and lignin, in which decomposition after carbonization and activation contributed to commercially valuable specific surface areas (>$2000m^2/g$) and specific capacitances (>120 F/g) that exceeded those of commercial activated carbon. The significant electrochemical performance of the herbaceous biomass-derived activated carbons indicated the feasibility of utilizing waste biomass to fabricate energy storage materials. Furthermore, with respect to both economic and environmental perspectives, it is advantageous to obtain activated carbon from herbaceous biomass waste given the ease of handling biomass and the low production cost of activated carbon.