• Journal of the Korea Organic Resources Recycling Association
• /
• v.3 no.1
• /
• pp.3-11
• /
• 1995

This study was conducted to estimate the stabilization degree of compost which made from Korean food wastes. To make the compost, food wastes were mixed with dried paper sludge, sawdust and the rotten wood waste which had cultivated mushrooms, and then mixture was composted in $1.1m^3$ of chamber which installed with the blower for maintaining the aerobic condition. Y value, EC and pH were changed remarkably for the early stage of composting. These changes showed that the compost of food wastes could be stabilized within 30~35 days and that the substrate, food wastes, can be easily used as energy source for microorganisms. Although these phyico-chemical properties indicated that food wastes could be composted within 30 days during the composting, the temperature of pile maintained over $50^{\circ}C$ for 80 days, and C/N ratio decreased gradually for over 50 days. In conclusion, more than 50 days were required to stabilize the compost of food wastes.

• Mycobiology
• /
• v.49 no.1
• /
• pp.1-14
• /
• 2021

Pleurotus species are commercially essential mushrooms and widely cultivated throughout the world. The production of Pleurotus mushrooms alone accounts for around 25% of that total cultivated mushrooms globally. In America and Europe, Pleurotus species are considered specialty mushrooms, whereas, in Korea, their cultivation is economically profitable, and it is one of the highly consumed species. Pleurotus species are predominantly found in tropical forests and often grow on fallen branches, dead and decaying tree stumps, and wet logs. Biographical studies have shown that the Pleurotus genus is among the more conspicuous fungi that induce wood decay in terrestrial ecosystems worldwide due to its formidable lignin-modifying enzymes, including laccase and versatile peroxidases. Pleurotus species can be grown easily due to their fast colonization nature on diversified agro-substrates and their biological efficiency 100%. Pleurotus mushrooms are rich in proteins, dietary fiber, essential amino acids, carbohydrates, water-soluble vitamins, and minerals. These mushrooms are abundant in functional bioactive molecules, though to influence health. Pleurotus mushrooms are finding unique applications as flavoring, aroma, and excellent preservation quality. Apart from its unique applications, Pleurotus mushrooms have a unique status delicacy with high nutritional and medicinal values. The present review provides an insight into the cultivation of Pleurotus spp. using different agro-waste as growth substances paying attention to their effects on the growth and chemical composition.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.3
• /
• pp.185-190
• /
• 2022

BACKGROUND: Most of the bottom ash(BA) from wood pellet-based thermal power plants that is not recycled is placed into landfill. BA has a function and structure similar to biochar. Hence, BA is classified as waste, but, it is predicted that BA can be used agricultural utilization. METHODS AND RESULTS: To investigate the effect of BA application on lettuce, growth characteristics and Pb contents were examined with BA application levels(0, 1, 2, 3 and 4 g/L), respectively, in hydroponic cultivation with Pb solution. Irrespective with BA application levels, the length, leaf number and fresh weight of lettuce in BA treatments were increased by 84.3~120, 36.2~39.0, and 215~322%, respectively, compared to the BA-0 treatment. The groups with BA treatments, Pb in the nutrient solution was adsorbed to the BA due to the surface area and functional groups of the BA, and the lettuce growth was maintained more smoothly than in the BA-0 treatment. BA application is considered to have created a favorable environment for lettuce growth in hydroponic cultivation with Pb solution. CONCLUSION(S): Although direct comparing the removal effect of heavy metal between BA and biochar is not present, the BA application in contaminated area suggested a significant meaning on the recycling waste, and increasing potential crop productivity by immobilizing heavy metal.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.1
• /
• pp.1-12
• /
• 2014

This study carried out life cycle assessment for evaluating environmental impacts of timber Arch-Truss bridge by using domestic Pinus rigida Miller glued-laminated timber throughout life cycle such as extraction, manufacturing, transportation, construction, use, dismantlement, transportation of waste, disposal and recycling. The life cycle GHG (GreenHouse Gas) emissions of the target bridge are 192.56 ton $CO_2$ eq. in 50 years. Especially, the life cycle GHG emissions of concrete used in the target bridge are 82.84 ton $CO_2$ eq. which accounts for 53.02% of the GWP (Global Warming Potential) in extraction and manufacturing stages. The target bridge is constructed of $116.57m^3$ of domestic Pinus rigida Miller glued-laminated timber and used timber has stored 104.72 ton $CO_2$. If an effect of carbon storage in timber is applied to the total GHG emissions of the target bridge, the GHG emissions can be reduced by 54.38%. In the case of substitution effect, if domestic Pinus rigida Miller glued-laminated timber replaces steel manufactures used in other bridge which has the same structure and life span as the target bridge, the GHG emissions in extraction and manufacturing stages can be reduced by 10.26% to 23.91%.

• Journal of Korean Society of Environmental Engineers
• /
• v.33 no.7
• /
• pp.523-529
• /
• 2011

This study has been performed to examine the influence of the size of particles on the stabilization in the aerobic stabilization equipment connected with MBT system. The biodegradable waste inside the reactor (60% of food waste, 25% of paper waste, 2% of wood waste and 5% of compost) has been charged in same composition. The degree of stabilization was compared and analyzed after charging with adjustment of particle size in 5 mm, 10 mm, 20 mm, 50 mm, 100 mm and state of no separation. The experiment revealed that highest temperature beyond $65^{\circ}C$ was shown in the particle size of less than 50 mm in change of temperature and the highest temperature was about $50^{\circ}C$ in reactor of 100 mm and no separation. The proportionality between generated quantity of $CO_2$ and particle size was not observed, even the highest in generated quantity was shown in over 100 mm. The weight changes based on wet and dry conditions in the reaction process showed the 30% and 46% of reduction in the smallest particle size of 5 mm and it showed the trend of the lower reduction rate at the bigger particle size. The water soluble $COD_{Cr}$ and TOC showed the reduction rate of 60% in reactor of particle size in 100 mm and no separation while the reduction rate comparing to the initial stage of reaction in the reactor of less than 50 mm was 80%. Such result derived the conclusion of acceleration in the decomposing stabilization of biodegradable material due to the decomposing rate of organic substance as the particle size of biodegradable waste gets smaller. It is concluded as necessary to react in adjustment under 50 mm of particle size as much as possible.

• 한국연소학회:학술대회논문집
• /
• 2014.11a
• /
• pp.375-378
• /
• 2014

In this study, we carried out torrefaction experiment using PKS(Palm Kernel Shell), and Bagasse as a raw material of oversee of herbaceous biomass and using waste wood and logging residue as a raw material of domestic of woody biomass. And then, by analyzing the physical & chemical properties, we investigated the characteristics as a fuel. By using the result of thermo gravimetric analysis, the biomass residue was torrefied for 30 minutes at a temperature range of $250-350^{\circ}C$ in anaerobic condition. As a result, torrefied materials of moisture content are lower than raw, but of fixed carbon, calorific value and ash are higher than raw.

• Journal of Energy Engineering
• /
• v.27 no.3
• /
• pp.36-40
• /
• 2018

Climate change is one of the major issues in both the developed and developing world. Greenhouse gas (GHG) emission is one of the implications for climate change. It is increasing rapidly. Although the emission is much less when compared to the rest of the world, Ethiopia has also faced this global issue. The major source for GHG emission in Ethiopia is agriculture. Therefore, the agriculture sector has to be given more attention in Ethiopia. To overcome the problem, Climate-Resilient Green Economy (CRGE) strategy has been initiated. One way of executing this target is to create a sustainable and environmentally friendly pathway to use agricultural byproducts. Sugarcane is one of the major plants in Ethiopia. Its byproducts are bagasse, molasses, and press mud. Since it is a waste product, it is economical and creates a sustainable and green environment by reducing GHG emissions. Sugarcane byproducts have versatile applications like as fuel, as cement replacing material, as a mitigation for expansive soils, as biosorbent for the treatment of water and wastewater and also as a wood material. However, Ethiopia has not used this byproduct massively as it is readily available. This paper reviews the possible applications of sugarcane byproducts to mitigate climate change.

• Journal of Korean Society for Atmospheric Environment
• /
• v.30 no.6
• /
• pp.538-544
• /
• 2014

A traditional fireplace has been used, but not much, for heating and cooking in rural area, Korea. Traditional fireplace as one type of biomass burnings is also emitting various air pollutants. Air pollutants emission from traditional fireplace was estimated in this study. There are two types of traditional fireplace, one for combined heating and cooking, the other one for cooking only. Types of fuels mostly used in traditional fireplace were wood, agricultural residue, solid waste. Activity levels such as fuel types, amount of fuel loading, and temporal variation were investigated by field survey over Korea. Estimated annual emissions from traditional fireplace were CO 6,335.0, NOx 555.0, SOx 9.6, VOC 1,771.7, TSP 181.4, $PM_{10}$ 119.9, $PM_{2.5}$ 96.2, $NH_3$ 1.4 ton/yr respectively. When emissions compared with the national emission inventory (CAPSS: Clean Air Policy Support System) of 2010 year, CO and $PM_{10}$ occupy 0.8% and 0.1% of total national emission, respectively.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 1979.04a
• /
• pp.113.1-113
• /
• 1979

Each year, vast amount of agricultural crop residues are produced (about 60 percent of the total crop production), which have not been effectively utilized because they are bulky and lignocellulosic, thus having little fuel energy per unit volume. Using treated plant residues as animal feeds could result in an ultimate saving of fossil fuel energy and a more effective utilizat ion of products created by the photosynthetic process. Feeding the residues to animals would decrease the pollution potential, but these residues are difficult for even a ruminant animal to digest. If cellulosic wastes produced from cereal grain straw and wood could be digested, land now used for producing forage add grain cnuld be shifted to food crops for humans. During the past decade, considerable efforts were made to utilize crop residues. These utilization methods can be broadly grouped into for categories: (1) direct uses, (2) mechanical conversions, (3) chemical conversions and (4) biological conversions. Agricultural crop residues consist mainly of cellulose, hemicellulose, lignin, pectin, andother plant carbohydrates. The nature of the constituents of these residues can be best utilized as one of the five FS: Fuel, Fiber, Fertilizer, Feed and Food. Many processes have teen proposed and some are in industrial production stage. However, economics of the process depend on the location where availability of other competitive products are different.

• Journal of Biosystems Engineering
• /
• v.43 no.1
• /
• pp.14-20
• /
• 2018

Purpose: The purpose of this study was to investigate the performance of a vacuum pyrolysis system, to analyze bio-oil characteristics, and to examine the applicability for farm-scale capacity. Methods: The biomass was pyrolyzed at 450, 480, and $490^{\circ}C$ on an electric heat plate in a vacuum reactor. The waste heat from the heat exchanger of the reactor was recycled to evaporate water from the bio-oil. The chemical composition of the bio-oil was analyzed by gas chromatography-mass spectrometry (GC-MS). Results: According to the analysis, the moisture content (MC) in the bio-oil was approximately 9%, the high heating value (HHV) was approximately 26 MJ/kg, and 29 compounds were identified. These 29 compounds consisted of six series of carbohydrates, 17 series of lignins, and six series of resins. Conclusions: Owing to low water content and the oxygen content, the HHV of the bio-oil produced from the vacuum reactor was higher by about 6 MJ/kg than that of the bio-oil produced from a fluidized bed reactor.