• Mycobiology
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• v.43 no.4
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• pp.423-434
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• 2015

The study was conducted to compare the effects of different agro-wastes on the growth, yield, and nutritional composition of oyster mushrooms Pleurotus ostreatus (PO) and Pleurotus cystidiosus (PC). Seven substrate formulas including sawdust (SD), corncob (CC), sugarcane bagasse (SB) alone and in combination of 80 : 20, 50 : 50 ratio between SD and CC, SD and SB were investigated. The results indicated that different substrate formulas gave a significant difference in total colonization period, characteristics of fruiting bodies, yield, biological efficiency (BE), nutritional composition and mineral contents of two oyster mushrooms PO and PC. The results showed that increasing CC and SB reduced C/N ratio, and enhanced some mineral contents (Ca, P, and Mg) of substrate formulas. The increased amount of CC and SB of substrate formulas enhanced protein, ash, mineral contents (Ca, K, Mg, Mn, and Zn) of fruiting bodies of both mushrooms. Substrates with 100% CC and 100% SB were the most suitable substrate formulas for cultivation of oyster mushrooms PO and PC in which they gave the highest values of cap diameter, stipe thickness, mushroom weight, yield, BE, protein, fiber, ash, mineral content (Ca, K, and Mg) and short stipe length. However, substrate formula 100% CC gave the slowest time for the first harvest of both mushrooms PO and PC (46.02 days and 64.24 days, respectively). It is also found that the C/N ratio of substrate formulas has close correlation with total colonization period, mushroom weight, yield, BE and protein content of mushroom PO and PC.

• Journal of Energy Engineering
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• v.26 no.1
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• pp.76-83
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• 2017

In this paper, the carbon resources recycling of the overview of coffee waste generation in Vietnam. Since few years, there has been a significant research studies was done in the areas of coffee waste generation areas and also waste water generation from coffee production. The coffee residue (solid) and waste water (liquid) both are caused the underground water contamination and also soil contamination. These residues contain high organic matter and acid content leads to the severe threat to environment. In second stage of coffee production process, the major solid residue was generated. Various solid residues such as spent coffee grounds, defective coffee beans and coffee husks) pose several environmental concerns and specific problems associated with each type of residue. Due to the unlimited usage of coffee, the waste generation is high. At the same time, some researchers have been investigated the spent coffee wastes are the valuable sources for various valuable compounds. Biodiesel or biomass productions from coffee waste residues are the best available utilization method for preventing the landfill problems of coffee waste residues.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.251-268
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• 1986

Selecting a site for the safe disposal of radioactive waste requires the evaluation of a wide range of geologic, mineralogic, hydrologic, and physicochemical properties. Although highly diverse, these properties are in fact interrelated. Site requirements are also diverse because they are influenced by the nature of the radionuclides in the waste, for example, their half-lives, specific energy, and chemistry. A fundamental consideration in site selection is the mineralogy of the host rock, and one of the most ubiquitous mineral groups is clay minerals. Clays and clay minerals as in situ lithologic components and engineered barriers may playa significant role in retarding the migration of radionuclides. Their high sorptivity, longevity (stability), low permeability, and other physical factors should make them a very effective retainer of most radionuclides in nuclear wastes. There are, however, some unanswered questions. For example, how will their longevity and physicochemical properties be influenced by such factors as radionuclide concentration, radiation intensity, elevated temperatures, changes in redox condition, pH, and formation fluids for extended periods of time? Understanding of mechanisms affecting clay mineral-radionuclide interactions under prevailing geochemical conditions is important; however, the utilization of experimental geochemical information related to physicochemical properties of clays and clay-bearing materials with geohydrologic models presents a uniquely challenging problem in that many assessments have to be based on model predictions rather than on experiments. These are high-priority research investigations that need to be addressed before complete reliance for disposal area performance is made on clays and clay minerals.

• Resources Recycling
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• v.25 no.3
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• pp.29-36
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• 2016

The characteristics analysis and pH neutralization test were carried out to use of slurry generated from recycling processes of construction wastes. D (5.0) of raw sludge was $42.4{\mu}m$ and over 60 % of sludge distribute under 45 um (-325 mesh). Muscovite and carbonate minerals were main minerals of fine particles, and the portion of carbonate minerals increased as particle size decreased. Although the more heavy metals were observed in the finer particle size, the contents was found to be less than Korean contaminated soil regulation (area 2). The effects of flocculants addition for accelerating solid-liquid separation were negligible because the slurry already contains excess of coagulant added in the waste concrete recycling process. It was difficult to neutralize the sludge supernatant due to high pH (about 12) by adding acids, but the introduction of $CO_2$ decreased the pH to 8.5, The precipitate recovered during $CO_2$ introduction was determined to be $CaCO_3$ with XRD, and it indicates that high pure $CaCO_3$ could be obtained during the process.

• Journal of Energy Engineering
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• v.26 no.4
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• pp.14-22
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• 2017

Coffee consumption has been increased all around world as well as in South Korea. Coffee by-products occurred from the coffee consumption also have been rapidly increased, but the technology and methods to handle the by-product have not been much developed, resulting the severe environmental problems in soil and water. In order to solve this environmental problem, using the coffee by-product, eco-friendly and cheap methods for the recycling have been actively discussed and suggested. In this article, we discussed the types and characters of the coffee by-product and investigated the trend about the methods for utilizing the coffee by-product. In addition, we figured out the current status of coffee waste in Seoul, South Korea and discussed plans that Seoul government is working on to handle the coffee waste.

• Resources Recycling
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• v.14 no.6 s.68
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• pp.37-43
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• 2005

[ $LiCoO_{2}$ ] nanoparticles were synthesized from leach liquor of lithium ion battery waste using flame spray pyrolysis. Electrode Materials containing lithium and cobalt could be concentrated with thermal and mechanical treatment. After dissolution of used cathode materials of the lithium battery with nitric acid, the molar ratio of Li/Co in the leach liquor was adjusted at 1.0 by adding a fresh $LiNO_{3}$ solution. The nanoparticles synthesized by the flame spray pyrolysis showed clear crystallinity and were nearly spherical, and their average primary particle diameters ranged from 11 to 35 nm. The average particle diameter increased with an increase in the molar concentration of the precursor. Raising the maximum flame temperature by controlling the gas flow rates also led to an increase in the average diameter of the particles. The $LiCoO_{2}$ powder was proved to have good characteristics as cathode active materials in charge/discharge capacity and cyclic performance.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.171-178
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• 2016

Extensive efforts from all over the world have been made to solve energy problems, such as high oil prices, global warning due to the depletion of oil. Among them, biofuel has been drawing attention as a clean energy, which can replace fossil fuels. However, conventional biofuels were often converted from eatable biomass such as sugar cane, corn and soy which should be replaced with uneatable biomass. In this study, a techno-economical evaluation of the gasification of biomass waste with mixed alcohol synthesis process was performed. Considering available domestic biomass wastes, a 2000 ton/day conversion plant were assumed to produce 533000 L/day ethanol. Also, financial data from previous studies were evaluated and used and economical sensitivities with various operation conditions were established. Economic analysis were conducted by the payback period and internal rate of return (IRR) and net present value (NPV). Sensitivity analyses of raw material costs, initial investment, the major process cost, ethanol price changes and operating costs were all performed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.6 no.1
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• pp.57-67
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• 2000

All crude oil carries a little of water, sand, and mineral sediment molecules tightly bounded with hydrocarbons. The result is the gradual precipitation of these heavier elements into thick, granular petroleum by products known as crude oil sludge. The oily sludges in ship tanks and in storage facilities have to be treated efficiently in order to keep the security and the capacity of storage facilities, to protect a serious environmental pollution, and to retrieve lost resource. The oily sludge treatment system should be designed to satisfy requirements mentioned in safe work condition. As a basic study, in this paper, an oily sludge treatment system by ultrasonic waves was proposed. Then, the features of ultrasonic energy and recovery of sludge with ultrasonic waves are investigated by experiments. As results, we found that ultrasonic waves are a new energy to flow oil sludge environment-friendly in safe work condition. In addition, it was shown that ultrasonic energy is more efficient than thermal energy in treating oil sludge, and that the volume of wastes for disposal is reduced remarkably.

• Korean Journal of Crystallography
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• v.12 no.1
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• pp.20-24
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• 2001

NiZn-ferrite was synthesized usign waste iron oxide catalysts which were produced from styrene monomer process and buried underground as an industrial wastes. The spinel type ferrite was obtained by calcination and sintering of the mixture of finely ground waste catalysts, nickel oxide and zinc oxide powders. The sintered body of Ni/sub 0.5/Zn/sub 0.5/Fe₂O₄ composition at 1230℃ for 5 hours showed the density of 5.38g/㎤, and initial permeability of 59 at 1 kHz. Not only cerium oxide, which existed as a major component in the catalyst, but also unicorporated NiO and ZnO into spinel structure remained as second phases after sintering.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.34-39
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• 2001

Following the trends around the world in the 1990's, Australia has been promoting recycling as a means to reduce wastes and at the same time improve the economics of metal processing. Of significance to the metal processing industry is the recycling of steel and aluminium, mostly from cans collected from households. The recycling of cyanide during gold processing has also been evaluated extensively, involving many R&D activities currently conducted in several laboratories and commercial plants in Australia. This paper presents an overview of the above issues, evaluating facts and data collected on metal recycling. The technologies currently developed and evaluated for cyanide recycling are also discussed.