• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1039-1048
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• 2020

Food waste causes various economic losses and environmental pollution problems such as soil pollution and groundwater pollution. Food waste has been used as a resource in various forms and has been used mostly for feed and composting. This study compared microalgal nutrient medium (BG-11) with food waste compost to determine the possibility of using it as a culture medium. Scenedesmus quadricauda was isolated and cultured in an eutrophic reservoir and incubated for 3 days in distilled water before laboratory use. Food waste compost was produced in two food waste processing facilities, and hot water was extracted in the laboratory to be used for microalgae cultivation. The growth curve of the microalgae was analyzed based on the Chl-a concentration measured during the experiment, and the growth rate of the microalgae grown in the food waste compost was compared with the growth rate of those grown in the nutrient medium. Food waste compost showed a similar growth rate to that of the nutrient medium, and there was a difference depending on the manufacturing facility. The growth of microalgae in such food waste was further amplified when trace elements were added and showed better growth than that of the nutrient media. Particularly, when trace elements were added, the growth rate increased, and the growth period was further extended. Therefore, food waste compost can be sufficiently utilized as a microalgal culture medium, and if trace elements are added, it is considered that microalgae can be more effectively cultured compared to the existing nutrient medium.

• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.8-18
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• 2006

The aim of this study is to evaluate the emission characteristics of mercury, lead, arsenic, and selenium from medium size municipal solid waste incinerators(MSWIs) in Korea. The concentrations of mercury, lead, arsenic, and selenium emitted from medium size MSWI stack were $2.67\;{\mu}g/Sm^3,\;0.38\;mg/Sm^3,\;1.33\;{\mu}g/Sm^3,\;0.28\;{\mu}g/Sm^3$, respectively. The concentration levels of mercury, lead, arsenic in flue gas from medium size MSW incinerator stacks selected were nearly detected under the Korea criteria level. Removal efficiencies of mercury, lead, arsenic, and selenium in waste heat boiler(WHE) and cooling tower(CT) were $90.36\%,\;69.76\%,\;43.04\%,\;40.64\%$, respectively. In general, the removal efficiencies of mercury and lead in WHE were higher than those of arsenic and selenium in WHE. Emission gas temperature reduction from waste heat boiler(WHB) and cooling tower(CT) can control mercury and lead of medium size MSWIs. To evaluate the relationship between mercury, lead, arsenic, selenium of fly ash and those of flue gas, it was carried out to correlation analysis of each metal concentration in the fly ash and in the flue gas from medium size MSWIs. From the correlation analysis, the coefficients of mercury, lead, arsenic, and selenium were 0.61, -0.38, 0.87, 0.28, respectively. The results of correlation analysis revealed that it should be highly positive to the correlation coefficients of mercury and arsenic in the fly ash and those of the flue gas emitted from medium size MSWIs. As it were, the concentrations of mercury and arsenic of flue gas from medium size MSWIs are high unless mercury and arsenic in fly ash are properly controlled in dust collection step in medium size MSWIs. It was also concluded that mercury, lead, arsenic, and selenium from MSWIs stacks could be controlled by waste heat boiler(WHE) and dust collecting step in medium size MSWIs.

• Resources Recycling
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• v.22 no.4
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• pp.46-54
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• 2013

The produced quantity of waste plastics including waste vinyls was assumed as about 5 million tons per year. The quantity of waste vinyls produced from the waste recycling center among total quantity of waste plastics was estimated as about 1 million tons per year. Most of waste vinyls produced from the waste recycling center were recycled as refuse plastic fuel(RPF) or recycled feedstock material. In this study, the medium material using waste vinyls was made by the melting process of heat medium heating and the tensile strength was analyzed for checking the usable possibility of recycled waste vinyl material by comparing with the existent product. In order to use the medium material for producing the recycled product, it can be considered that the tensile strength of medium material is more than 100 $kgf/cm^2$.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.197-201
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• 1995

For 2 years $(1993{\sim}1994)$, study on development of cheap medium for Pleurotus ostreatus revealed that paper sludge contain more CaO and similar T-C, T-N, $P_2O_5$, MgO but less $K_2O$ than any other medium material in chemical property. Mixed treatment (rice straw + paper sludge 10, 30, 50%, cotton waste + paper sludge 10, 30, 50%, cotton waste + rice hull 20 + paper sludge 10, 30, 50, 70%) is similar or fast a little in mycelial growth and is similar or fast $1{\sim}2$ day in period of primordia formation than cotton waste medium, and in the yield to each medium type also increased but excepted in rice hull 20% + paper sludge 70%, especially mixed medium at 7:3 ratio of cotton waste and paper sludge is best treatment because it is increased to 21%. In economical analysis, mixed medium at 7:3 ratio of cotton waste and paper sludge is increased to 50% compared to cotton waste medium in relative income.

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.27-31
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• 2007

The experiment has investigated the effects of blending rate of waste rockwool in nursery media on growth of Marygold 'Yellow boy' plug seedlings. A commercial plug medium containing 10% zeolite, 10% vermiculite, 5% perlite, 10% peatmoss and 65% cocopeat was used as the control, and the other media compounded with 10% of zeolite, vermiculite, perlite and peatmoss and 10, 30, and 50% of waste rock-wool. There was not significant difference in germination rate ot Marygold between treatments. Plant height, number of leaves, stem diameter and leaf area were higher in commercial plug medium and compound nursery media containing 50% of waste rockwool than 30 or 10% of waste rockwool. Fresh weight and dry weight of shoot and root increased in the treatment of commercial plug medium and the medium of 50% waste rockwool than 10 and 30% of waste rockwool. These results suggested the possibility of utilization of waste rockwool for medium components of plug seedlings.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1205-1214
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• 2005

This study was carried out to investigate the emission characteristics of volatile metals(Hg, As, Se) and semi volatile metals such as Pb from small and medium size municipal solid waste incinerators(MSWIs). The concentrations of Hg, Pb, As and Se in emission gas from small size waste incinerators were higher than those of medium size waste incinerators. This is probably due to less air pollutant control devices and high emission gas temperature of the small size waste incinerators relative to the medium size waste incinerators. Emission gas temperature from small and medium size waste incinerators were divided into 2 groups. The first group was about $100^{\circ}C$ and the second roup in the range of $400{\sim}700^{\circ}C$. The concentrations of emission gas at the second group were Hg $70.43\;{\mu}g/Sm^3$, Pb $0.94\;{\mu}g/Sm^3$, As $9.83\;{\mu}g/Sm^3$ and Se $5.05\;{\mu}g/Sm^3$. The concentrations of Hg, Pb, As and Se at the first group were lower than those found at the second group. Besides, the removal efficiencies of Hg in medium size waste incinerators were $55.2{\sim}95.9%$. Emission gas temperature reduction from waste heat boiler(WHB) contribute to control of Hg. Based on above results, we postulate that the temperature of flue gas should play a very important role in volatile metal control in small and medium size MSWIs. In order to improve the volatile metals removal efficiency, the temperature of cooling system must be controlled and the air pollution control device should be operated properly.

• KSBB Journal
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• v.14 no.5
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• pp.550-560
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• 1999

There have been many research efforts on biofilter modeling including Ottengraf et al. who derived a model equation for the concentration profile of pollutants(e.g., VOCs) in the biolayer and solved their outlet concentration of the waste gas stream through biofilter. However, for most of research works done so far, the effects to explain the effect of adsorption of organic particles to medium(i.e., adsorbent) have been ignored. In this work biofilter modeling accompanying process lumping has been proposed and the theoretical effect of adsorption property of the medium, on the biofilter performance of eliminating organic components in waste gas stream, is intensively discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.186.1-186.1
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• 2011

Most of waste plastics including waste vinyls have been recycled up to about 50% of waste production, 4.5 million ton per year in 2009. To fundamentally increase the recycled amounts of waste plastics to waste production, the energy utilization of waste plastics is inevitable. But the contents of PVC included in waste plastics can limit the use as a RPF and make the air pollutants such as HCl and dioxin when it burns in the combustion system. Accordingly the source dechlorination by using heating method can be applied to make low contents of HCl as less than 0.6%. In this study the twin screw reactor using heat medium was used for the source dechlorination. As results of study, it was considered that this system is effective for the industrilal application.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.364-371
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• 2019

The use of GRAS microorganisms isolated from fermented foods during amylase production using an economical food-waste medium provides more opportunities to produce amylase with a wider range of applications. Hence, this study aimed to isolate a good amylase-producing fungi from the traditional Indonesian fermented cassava, gatot, and to identify the amylase-producing capability of the isolate in a potato peel waste (PPW) medium. Black-colored fungi isolated from gatot was morphologically identified and the amylase produced was characterized using SDS-PAGE and Native PAGE. The isolate was then grown on PPW medium, and the amylase produced was further characterized. Morphological identification and enzyme characterization revealed that the Aspergillus niger aggregate F isolated from gatot secreted an active extracellular ${\alpha}$-amylase with an optimum pH of 5-6. In conclusion, Aspergillus niger aggregate F isolated from gatot can be used to produce ${\alpha}$-amylase using PPW as a medium.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.17-21
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• 2009

This experiment was conducted to clarify the effect of waste tire chip on the growth and nutrient content of Cymbidium Pine Clash 'Moon Venus'. There were no significant differences between bark only medium and mixed medium in leaf and stem growth. But in both medium and large size chip only, the leaf and stem growth decreased remarkably. The total number of roots, new roots and root length had similar tendency as in leaf and stem growth. In medium and large tire chip only, the decayed roots increased. There were no significant differences between bark only medium and mixed medium in total sugar, starch, content of chrolophyll, N, P and K, but decreased significantly in both medium and large size chip only.