Giant miscanthus (GM) is an Asian grass that can produce biomass in high yields per land area. It can be used as a cathode material in lithium sulfur (Li/S) batteries. Giant-miscanthus-derived activated carbon (GMAC) is prepared via carbonization of GM followed by KOH activation. It is prepared with a large amount of KOH, and thus contained more defects but had a highly porous structure and graphitic cluster lattice. GMAC has a large specific surface area of 3327 m2/g and a large total pore volume of 1.86 cm3/g. The pore volume served as a storage space for the retention of polysulfides, thereby inhibiting the shuttle effect. When a GMAC–sulfur composite cathode is tested in a Li/S battery, an initial discharge capacity of 1148 mAh/g can be attained at 0.1 C. In a cyclic charge–discharge experiment at 1 C, discharge capacities of 529 mAh/g and 248 mAh/g are observed in the first and 200th cycles, respectively.

거대억새의 수확물은 물리적 특성상 밀도가 낮아 바로 운송하기에 경제적으로 적합하지 않다. 그러므로 현장에서 바로 전처리 작업을 통하여 거대억새 수확물의 밀도를 높여줄 수 있는 기계 개발이 필요하다. 본 연구에서는 현장에서 절단, 분쇄, 압축 성능을 극대화하여 거대억새 분쇄물의 압축밀도를 높여줄 수 있는 두 가지 형태의 기계를 개발하였다. 필드에서 사용할 수 있도록 두 가지 형태의 기계는 동력원으로 전기 혹은 트랙터 동력취출장치인 PTO로 작동되도록 하였다. 결과적으로 개발된 절단 및 분쇄 통합시스템은 분쇄 및 절단을 동시에 처리하여 시간당 1 ton 이상 처리가 가능하였다. 또한, 개발된 압착기는 압축된 분쇄물이 240 g/L 이상 밀도로 압축할 수 있었다. 개발된 거대억새 전처리 가공 기계들은 유통상 경제적 이점을 증가시킴으로써 다양하게 활용할 수 있다.

This paper presents a landscape planning proposal based on rural ecotourism at the giant miscanthus Field in Iksan Jeollabuk-do. The recently developed giant miscanthus (“Goedae Uksae 1”) is a promising bio-energy crop, and several plantation fields will be constructed nationally. Since the site is 184ha and located near the Geumgang river, its ecological and landscape potential is very high. The utilization of the site’s tourism resources is focused in the four directions of giant miscanthus landscaping, regional resource networking, ecotourism, and bio-energy planning. The main concept of the planning is “Living Landscape and Breathing Cultures,” and the site is divided into the six spaces of plantation field, riverside, Yongan eco-park, energy avenue, bio-energy center, and special-landscaping area through the river bank. The main facilities of these spaces comprise a reed maze, an observatory, boardwalks, energy campgrounds, and landscape lighting. Special and eye-catching landscapes with the themes of giant miscanthus, harmony, opening, closing, and sequence were adopted and suggested at the major points of the site. To produce various open, closed, and winding landscapes, eye-view focused planting patterns of centralizing, scattering, and mixing of various similar species were adopted to stimulate curiosity and draw attention.

To restore reclaimed land, it needs to be supplemented with organic matter; this is especially true for Korea, where organic matter constitutes only one-tenth of conventional agricultural soils. The giant Miscanthus, a perennial grass known for its extensive biomass, shows signs of being an excellent source of organic matter for restoring reclaimed land. Therefore, the objectives of this study were to (i) evaluate the feasibility of using the giant miscanthus as an organic resource within the context of re-using reclaimed land for agricultural purposes (i.e., potato cultivation), and (ii) determine the optimum fertilization rate for the potatoes while the giant miscanthus is being used as an organic resource. Our results show that after 180 days, giant miscanthus lost 23–47% of its original dry weight, with the extent of the loss dependent on soil salinity. Nutrient concentrations (Mg2+, Na+) continued to increase until the end of the study period. In contrast, potassium (K+) and the ratio of carbon to nitrogen (C/N) decreased until the end of the study period. Specifically, after 180 days, low salinity topsoil treatments had the lowest C/N ratio. In the first year, 150 % of standard N rates were required for the potatoes to achieve maximum productivity; however in the 2nd year, standard rates were sufficient to achieve maximum productivity. Overall, this implies that even though the application of giant miscanthus did eventually improve soil quality, increasing crop yields, N fertilization is still necessary for the best outcomes.

Land application of biochar (or charcoal) has increasingly been recognized due to its favorable effect as soil amendments. However, depending upon the nature of biomass and pyrolysis condition, biochar may be rich in hazardous inorganic elements. Giant Miscanthus showed its potential as a promising source for biochar manufacture but, the risk of heavy metal leaching from Giant Miscanthus-derived biochar (GMB) has not investigated. The objective of this study was to investigate the heavy metal leachability of GMB manufactured from 3 different temperatures (400, 500, and 700oC). Elemental composition of C, N, H, S, O and 18 metals were analyzed. Leaching concentration of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn was analyzed using 4 different methods (0.1 N HCl, 1 N NH4OAc, toxicity characteristic leaching procedure, and synthetic precipitation leaching procedure). For comparison, same analysis were performed for two char materials, municipal solid waste char (MWC) and sewage sludge char (SSC), manufactured from pilot-scale muncipal waste gasification plant. Elemental composition of GMB complied with the fertilizer guideline whereas the several heavy metal content (Cd, Ni, Pb, and Zn for MWC, Cr, Cu, Ni, and Zn for SSC) was beyond the criteria. From leaching test, concentration of heavy metals from GMB was positively increased with pyrolysis temperature and the acidity of extractant solution. Leaching concentration of plant nutrients (Ca, K, and Mg) was the highest by 1N NH4OAc. Meanwhile, leaching concentration of Cu from MWC and Pb from SSC exceeded the regulatory standard of Korea and US EPA, respectively. In conclusion, with respect to the risk of heavy metals, Giant Miscanthus-derived biochar will be suitable for land application as a soil amendment, while care should be taken for using municipal waste-derived char materials.