• Resources Recycling
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• v.14 no.4 s.66
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• pp.41-46
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• 2005

Waste aluminum dross is a major waste in the aluminum scrap smelters and its major components are alumina and metallic aluminum. In this study, waste aluminum dross was leached with sodium hydroxide solution to extract the remained aluminum into the solution, and aluminum hydroxide was recovered from the leached solution. The dross residue generated at the leaching step was recycled into alumina base ceramic materials through a series of treatments such as washing, drying and roasting. Also, a pilot plant was constructed and tested to demonstrate the developed technology. Four tons of waste aluminum dross could be processed per day. From the test run of the pilot plant, it was confirmed that the developed technology could be applied to commercialization.

• Resources Recycling
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• v.7 no.2
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• pp.39-45
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• 1998

We smelted thc pellets made by mixing the distilled carbon from wlISte Lires, LD converter dust and slag with reduction process in the revcrberatory furnace. Thc obtained results are as follows 1) The removal mte of zinc appears above 97% after T reducing the pellets at $1300^{\circ}C$ for Ihr and the zinc content in the residue are 0.1~D.2%. 2) Under the mixing condition of 500 g LD dust. 150-200 g LD slag and 30-50 g distilled carbon of waste lires the removal raho of zinc shows above 95%, while t the 50-60% Fe remains in the residue. 3) After smelting at $1350^{\circ}C$ for 3hrs, the recovery ratio of pig iron reduced from lhe p pellets containing 15-20% LD slag and 4.1-7.2% distilled carbon of waste tires appears in the range of 89.3-92%. 4) Tbe c chemical composition of the recovered pig iron is 1.7%C, O.05%P, 0.05%S and balance Fe. 5) Tbe recovered dust from the d dust collcctor alter finishing the reduction rcaction appears as a crude zinc oxide conLaining 60% zinc.

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

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.487-496
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• 2021

Microalgae is one of the promising biodiesel feedstock with high growth rates compared to those of terrestrial oil crops. Despite its numerous advantages, biodiesel production from microalgae needs to reduce energy demand and material costs further to go to commercialization. During solvent extraction of microalgal lipids, lipid-extracted algae (LEA) cell residue is generated as an organic solid waste, about 80-85% of original algal biomass, and requires an appropriate recycling or economic disposal. The resulting LEA still contains significant amount of carbohydrates, proteins, N, P, and other micronutrients. This review will focus on recent advancement in the utilization of LEA as: (i) utilization as nutrients or carbon sources for microalgae and other organisms, (ii) anaerobic digestion to produce biogas or co-fermentation to produce CH₄ and H₂, and (iii) conversion to other forms of biofuel through thermochemical degradation processes. Possible mutual benefits in the integration of microalgae cultivation-biodiesel production-resulting LEA with anaerobic digestion and thermochemical conversion are also discussed.

• Journal of Korea Soil Environment Society
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• v.1 no.2
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• pp.3-13
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• 1996

The efficiency of bioremedation can be measured by the enumeration of microorganism, respiration rate and decomposition rate. The side-effect can be measured by using Daphnia, oyster larvae and rainbow trout. Oxygen transfer could be a problem in the on-site treatment. For these, hydrogen peroxide can be used for solvents such as benzenes. Oleophilic nitrogen and phosphorus can be added for the treatment of oil pollution. Mixed microbial population or pure culture can be used for the inoculum. The pure culture used is Pseudomonas and Phanerochate. Sometimes enzymes are added and Photodegadation is coupled to increase the efficiency. For the treatment of oil pollution residue on soil such as waste lubrication oil and machine oil sludges, top soil of 15cm∼20cm depth is plowed and oil residue with approximately 5% concentration is applied. The optimum pH range is 7∼8, the ratio of phosphorus to hydrocarbon is 1:800. Appropriate drainage is necessary. For the treatment of marine oil pollution residue, addition of oleophilic fertilizer is effective. Air pollutiant such as oder can be treated by bioremediation. In this case, biofilters or biosrubbers are used for the reactor.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.4
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• pp.5-11
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• 2023

This study was conducted to improve energy efficiency and problems such as clumping and fouling in the glue zone that occur in the moisture content range of 40 to 60% when sewage dehydration residue is directly fed into the dryer. The temperature of the hot air is low at 270~300℃, and the paddle-type flotation method and dehydrated residue are applied to the circulated heat storage media to increase the contact area with the hot air, thereby reducing energy recovery and gas emissions. The water content of the dried residue is 2.7. ~7 .5%, the heat of evaporation of moisture was 608.0~690.6 kcal/kg·H₂O, which confirmed an energy saving effect of about 8.8% compared to the heat of evaporation of moisture of 714.5 kcal/kg·H₂O when no heat storage media was used.

• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.2
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• pp.287-298
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• 1993

In this study, generation characteristics and distribution situation of the animal fat residue were investigated to identify it's management problems and to propose alternatives for the recycling and final disposal. Generation sources were the meat distribution net-work including about 170 slaughterhouses, 280 meat-packing plants, thousands of meat shops and restaurants etc. The daily total amount of the animal fat residue is about 700 ton/day. More than 60% of the generation sources were concentrated in Seoul metropolitan area. The residue was collected by about 300 men using old-fashioned devices like handcarts, bike and auto bike, transported to the recycling plants by about 60 collection agencies. The residue was processed to produce by-products such as grease, tallow, animal feed ingredient in the recycling plants. At present, however, a great number of unlicensed, and mostly small rendering processors without having pollution control facilities do the unlawful business. These small, old fashioned and unorganized businesses are creating environmental problems by disposing the waste in improper ways such as open burning and dump. Improvement of the distribution network, the large-scale plants, and the estabilishing proper infrastructures were suggested to overcome the problems for the sound fat residues reprocessing industry.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.15-26
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• 2017

This study was conducted to investigate and analyze the discharge characteristics of recyclable material from S-city, S-district, in order to improve the sorting efficiency in recycling sorting facility. The characteristics of recyclable materials collected were analyzed in three different scopes; source origin, collection and transportation, and sorting steps. The average of recyclable waste generation is $0.121kg/day^*man$. Regional collection period appears to be three times a week, and the density of mixed recyclable wastes showed the average of $202.4kg/m^3$ in the waste collection vehicle. In the analysis into the sorting steps, the average of carrying amount of mixed recycling products is 1,154.6 ton/month, the average of appeared density is $181kg/m^3$, the average amount of separated recycling products is 448.5kg/month, and the density of recycling residue is found out to be $48kg/m^3$. The sorting rate of recyclable material is 38.85% and the percentage of residues is 55.90%. Out of 7,744.8 tons of the total recyclable residues, 4,272.1 tons were found out to be possible recylable materials. As a result of increasing the recycling rate of residues, the encouragement of base-recycling, the automation and retrofit of sorting equipment, and energy recovery from recycling residue were discussed.

• Analytical Science and Technology
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• v.19 no.1
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• pp.86-95
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• 2006

This study was carried out to estimate leaching characteristics of incineration residues from municipal solid waste incinerators, and determine organic compounds in raw ash, leaching water and leaching residue. A total of 44 organic compounds, which were analyzed by GC/MSD and identified by wiley library search, were contained in bottom ashes. A total of 17 organic compounds were contained in fly ashes. Bottom ash and fly ash were found to contain a wide range of organic compounds such as aliphatic compounds and aromatic compounds. Organic compounds such as Ethenylbenzene, Benzaldehyde, 1-Phenyl-Ethanone and 1,4-Benzenedicarboxylic acid dimethyl ester were detected in raw ash, leaching water and residues (from bottom ash). Organic compounds such as Naphthalene, Dodecane, 1,2,3,5-Tetrachlorobenzene, Tetradecane, Hexadecane and Pentachlorobenzene were detected in raw ash, leaching water and residues (from fly ash). Through the leaching characteristics of incineration residue, it was represented that the open dumping of incineration residue can contaminate the soil and undergroundwater. In order to prevent environmental contamination that derived from extremely toxic substances in the incineration residues, it is particularly important that the incineration residues should be treated before disposal the incineration residues. Further study and proper management about leaching characteristics of organic compounds might be required.

• Resources Recycling
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• v.22 no.2
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• pp.71-77
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• 2013

Electronic products such as appliances, computers, and cellular phones have printed circuit boards (PCBs) in common and the PCBs in the waste electronic products contain valuable metals and organic resins. In Korea, recovery and recycling of the organic resins as well as the valuable metallics from the wastes are required indeed as the most of resources are being imported from abroad. In this article, the patents and papers for the recycling of organic residues from the waste PCBs were collected and analyzed. The open patents of USA (US), European Union (EP), Japan (JP), and Korea (KR) and SCI journals from 1979 to 2012 were investigated. The patents and journals were collected using key-words and filtered by the definition of the technology. The patents and journals were analyzed by the years, countries, companies, and technologies and the technical trends were discussed in this paper. It is showed sluggish relatively activity of published papers and patent applications for polymer manufacturing technology in local and abroad.