• Proceedings of the Korean Institute of Resources Recycling Conference
• /
• 2005.10a
• /
• pp.34-46
• /
• 2005

For treating a huge amount of plastic waste with the environment problem, pyrolysis of plastic waste into alternative fuel oil is one of important issue in recycling methods. This study was introduced over the trend of generation of plastic waste, pyrolysis technology in domestic and foreign countries, basic technology in pyrolysis process and new technology of pyrolysis developed in KIER (Korea Institute of Energy Research). The characteristics of process developed in KIER are the continuous loading treatment of mixed plastic waste with an automatic control system, the minimization of wax production by circulation pyrolysis system in non-catalytic reactor, the reuse of gas produced and the oil recovery from sludge generated in pyrolysis plant, which have greatly the advantage economically and environmetally. The experiment result data in 300 ton/yr pilot plant showed about 81 wt% liquid yield for 3 days continuous reaction time, and also the boiling point distribution of light oil (LO) and heavy oil (HO) produced in distillation tower was a little higher than that of commercial gasoline and diesel, respectively.

• Journal of the Korean GEO-environmental Society
• /
• v.21 no.10
• /
• pp.5-10
• /
• 2020

As the demand for the recycling of industrial by-products increases due to various environmental restrictions including the prohibition of ocean disposal, various studies regarding the recycling of industrial by-products are currently being carried out. One of the industrial by-product, coal ash is produced from thermal power generation; studies on the recycling of fly ash have been actively carried out and it is currently recycled in various fields. In the case of bottom ash, however, only a portion of the total amount generated is primarily processed into a particle size of 2~4mm or less than 2mm to be used for gardening purpose and light weight aggregate and so on. The remaining amount is buried at ash disposal sites. Therefore, various studies are needed to develop measures to use bottom ash. This study aimed at identifying the optimal particle size and mixing ratio of bottom ash to be used as CLSM aggregate. To this end, it evaluated the usability of bottom ash as CLSM aggregate, by investigating the flowability and strength change characteristics of CLSM produced with regard to the mixing ratio of weathered granite soil and bottom ash, particle size of bottom ash to be mixed and soil binder addition rate and conducting a heavy metal leaching test.

• Journal of Environmental Science International
• /
• v.25 no.11
• /
• pp.1575-1582
• /
• 2016

In this study, to provide basic information for design of a large-scale recycling system for fishery by-products, the food nutrient components, fertilizer components, and microbial composition of fertilizers and feed which were made of fishery by-products were analyzed before and after fermentation. The results of the analysis of the edible portion of fishery by-products indicated that calories per 100 g of crustaceans were the highest followed by those of fish and brown algae in order of precedence with values as follows; Korean Krill 94 Kcal, Portunus trituberculatus 65 Kcal, Lophiomus setigerus 58 Kcal, and Undaria pinnatifida 16 Kcal. As for changes in amino acids per 100 g of fishery by-products between before and after fermentation, calories per 100 g of P. trituberculatus decreased by 74.7% from 15.7 g to 4.0 g, that of L. setigerus decreased by 61.1% from 11.9 g to 4.6 g, that of Korean Krill decreased by 53.5% from 11.6 g to 5.4 g, and that of U. pinnatifida decreased by 49.4% from 1.7 g to 0.9 g. Among amino acids, those contained in fishery by-product fertilizers (liquid fertilizer) in large amounts were shown to be Glutaminic acid, Aspartic acid, Glycine, Lysin, and Leucine. The lipid content of Korean Krill decreased by 11.9% from 3.2 g to 2.8 g, that of L. setigerus increased by 2.0 times from 1.1 g to 2.2 g, that of P. trituberculatus increased by 4.5 times from 0.4 g to 1.7 g, and that of U. pinnatifida increased by 9.4 times from 0.2 g to 1.9 g. The ash (mineral) content of P. trituberculatus decreased by 82.5% from 26.2 g to 4.6 g, that of U. pinnatifida increased by 27.6% from 3.3 g to 4.2 g, that of Korean Krill increased by 21.9% from 3.1 g to 3.8 g, and that of L. setigerus increased by 88.7% from 1.2 g to 2.2 g. The microbial composition of liquid fertilizer using recycled fishery by-products was shown to be Bacteria, Actinomycetes, Fungi, Yeast, and Lactobacillus sp.

• Journal of Korean Society of Forest Science
• /
• v.83 no.2
• /
• pp.133-147
• /
• 1994

Wastepaper recycling has significant implications not only in providing scarce raw material input for the paper industry but in environmental concerns such as reducing solid waste disposal, energy conservation and preservation of forest resources. The objectives of this study was (1) to develop an econometric model of demand for and supply of wastepaper, (2) to forecast wastepaper consumption and price to the year 2000 applying the econometric models estimated and (3) to estimate the elasticity of variables which are included in the wastepaper supply and demand equations. In this study wastepaper was classified into three groups, old newsprint, old corrugated and mixed For each group such as demand and supply equation were estimated. The demand equations were estimated as a function of paper and paper product consumption and wholesale price index and supply equations as a function of wastepaper price, one year lagged paper and paperproduct consumption and transportation price. Applying the econometric models to forcasting results in the future consumption and supply of wastepaper projected as 11.645 million MT and 7.396 million MT in 2000, respectively. The rate of wastepaper self-supply is forcasted about 63.5% in 2000. Especially, the rate of old neswprint self-supply is predicted about 16% which means about 2.2 million MT of old newsprint should be imported from foreign countries. Lastly, some policy measures to promote wastepaper recycling rate based upon economic and physical characteristics of wastepaper and market structure are suggested.

• Clean Technology
• /
• v.26 no.2
• /
• pp.116-121
• /
• 2020

In this paper, the recycling of waste Ni-MH battery by-products for electric vehicle is studied. Although rare earths elements still exist in waste Ni-MH battery by-products, they are not valuable as materials in the form of by-products (such as an insoluble substance). This study investigates the recovering of rare earth oxide for solvent extraction A/O ratio, substitution reaction, and reaction temperature, and scrubbing of the rare earth elements for high purity separation. The by-product (in the form of rare earth elements insoluble powder) is converted into hydroxide form using 30% sodium hydroxide solution. The remaining impurities are purified using the difference in solubility of oxalic acid. Subsequently, Yttrium is isolated by means of D2EHPA (Di-[2-ethylhexyl] phosphoric acid). After cerium is separated using potassium permanganate, lanthanum and neodymium are separated using PC88A (2-ethylhexylphosphonic acid mono-2-ethylhexyl ester) and it is calcinated at a temperature of 800 ℃. As a result of the physical and chemical measurement of the calcined lanthanum and neodymium powder, it is confirmed that the powder is a microsized porous powder in an oxide form of 99.9% or more. Rare earth oxides are recovered from Ni-MH battery by-products through two solvent extraction processes and one oxidation process. This study has regenerated lanthanum and neodymium oxide as a useful material.

• Resources Recycling
• /
• v.28 no.4
• /
• pp.44-50
• /
• 2019

In the electric arc furnace process, the chemical energy such as the heat of oxidation reaction and the heat of carbon combustion etc. is consumed as 30% of the total input energy. In order to reduce $CO_2$ emission in EAF, it is necessary to decrease the use of electric power energy during scrap melting stage and increase the use of chemical energy. In general, when the carbon materials is individually charged into the molten steel, the carbon materials floated to the slag layer due to low density before it is dissolved in molten steel. When the concentration of carbon in the molten steel is high, the combustion energy of carbon by oxygen injection can lower the electric power energy and improve the chemical energy consumption. Therefore, an efficient charging methods of carbon material is required to increase the efficiency of carbon combustion heat. On the other hand, Al-dross, which is known as a by-product after Al smelting, includes over 25 mass% of metallic Al, and the oxidation heats of Al is lager than that of carbon. However, the recycling ratio fo Al-dross was very low and is almost landfilled. In order to effectively utilize the heats of oxidation of Al in Al-dross, it is necessary to study the application of Al-dross in the steel process. In this study, the dissolution efficiency of carbon and aluminum in molten steel was investigated by varying the reaction temperature and the mixing ratios of coke and Al-dross.

• Journal of Korean Home Economics Education Association
• /
• v.33 no.3
• /
• pp.173-187
• /
• 2021

The purpose of this research was to develop instructions for making upcycled clothing accessories related to the 'clothing management and recycling' unit of middle school home economics applying the design thinking technique. Teaching and learning process plans were developed according to the ADDIE model which includes the following process: analysis, design, development, implementation, and evaluation. The design thinking process includes understanding the related knowledge, sympathizing, problem identification(sharing perspectives) and idea development, making prototypes, testing, and making the actual product. Thirteen home economics teachers served as critics. Student feedbacks were collected to evaluate whether the course objectives were attained after the implementation. As a result, teaching and learning process plans, course materials, and evaluation rubrics for ten class sessions were developed. Student feedbacks confirmed the attainment of following five course objectives: improvement of ethical responsibilities through the exploration of various clothing recycling techniques, practice of creative and eco-friendly clothing culture, acquisition of the skills to use sewing tools safely, improvement of abilities to think, sympathize, and communicate, and exploration of aesthetic activities and fashion careers.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.6 no.2
• /
• pp.74-80
• /
• 2011

In this study, it is evaluated on the properties of mechanical performance, autogenous shrinkage and chloride resistance for application of high performance concrete for bridge deck overlay used slag powder and fly ash as a representative by-product of industrialization. According to test results, it is evaluated that the durability of concrete is improved the properties of chloride resistance, autogenous shrinkage and alkali aggregate reaction by using hydraulic mineral admixtures. It is considered to have a green construction and an economic feasibility on recycling of by-product as a improved concrete for durability and efficiency in materials and constructions.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.479-482
• /
• 2008

Since late of 2000, KIER has developed a novel pyrolysis process for production of fuel oils from polymer wastes. It could have been possible due to large-scale funding of the Resource Recycling R&D Center. The target was to develop an uncatalyzed, continuous and automatic process producing oils that can be used as a fuel for small-scale industrial boilers. The process development has proceeded in three stages bench-scale unit, pilot plant and demonstration plant. As a result, the demonstration plant having capacity of 3,000 tons/year has been constructed and is currently under test operation for optimization of operation conditions. The process consisted of four parts ; feeding system, cracking reactor, refining system and others. Raw materials were pretreated via shredding and classifying to remove minerals, water, etc. There were 3 kind of products, oils(80%), gas(15%), carbonic residue(5%). The main products i.e. oils were gasoline and diesel. The calorific value of gas has been found to be about 18,000kcal/$m^3$ which is similar to petroleum gas and shows that it could be used as a process fuel. Key technologies adopted in the process are 1) Recirculation of feed for rapid melting and enhancement of fluidity for automatic control of system, 2) Tubular reactor specially-designed for heavy heat flux and prevention of coking, 3)Recirculation of heavy fraction for prevention of wax formation, and 4) continuous removal & re-reaction of sludge for high yield of main product (oil) and minimization of residue. The advantages of the process are full automation, continuous operation, no requirement of catalyst, minimization of coking and sludge problems, maximizing the product(fuel oil) yield and purity, low initial investment and operation costs and environment- friendly process. In this presentation, background of pyrolysis technology development, the details of KIER pyrolysis process flow, key technologies and the performances of the process will be discussed in detail.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.222-222
• /
• 2011

Plastic product is increasing by the growth of its demand and most of refused plastics are incinerated or reclaimed. However, the refused plastic is not easily decomposed and has the environmental problem with its various toxic gas in case of incineration. Therefore, many countries such as USA, Japan, Germany and other developed industrial countries as well as Korea are interested in studying the recyclable resource of refused plastic. The macromolecular waste pyrolysis has the advantage of collecting of raw materials in high price and can at least get fuel gas or oil with high heat capacity. It also discharges low waste gas and low toxic gas including SOx, NOx and HCl heavy metals. However, pyrolyzed oil includes enough excess unsaturated hydrocarbons to form tar, which can cause the nozzle of engines to plug when pyrolyzed oil is used as fuel. Activated carbon was proven to have prominent adsorption capability among the other adsorbents that were mainly composed of carbon. This study examined the possibility of application in activated charcoal of its solid formation by analysing the feature of pyrolysis which is one of the chemical recycling methods and getting chemical analysis of the product and activated energy. Analyze the element of the oil produced by pyrolysis using GC-MS. The experiment of tar adsorption using fly-ash showed that fly-ash improved the optical intensity of pyrolyzed oil and decreased oxygen compounds in the pyrolyzed oil.