• Elastomers and Composites
• /
• v.46 no.4
• /
• pp.318-323
• /
• 2011

To recycle the waste tire rubber powder, rubber powder composite for waterproof sheet was prepared, and analyzed the effect of the kind of resin and the amount of crosslinking agent on the mechanical property of the composites. The elongation-at-break of the PE composite increased more than 3 times as EPDM was added into rubber composites. As the content of the crosslinking agent increased, the tensile strength of composite increased as well. When recycled polypropylene was used, the increase in composite's tensile strength was more than 3 times. Therefore to use the recycled PP in composite is more effective rather than PP in term mechanical properties.

• Proceedings of the IEEK Conference
• /
• 2001.10a
• /
• pp.751-754
• /
• 2001

A possibility of using waste plastics as a source of secondary fuel in blast furnace has been of recent interest. The success of this process, however, will be critically dependent upon the optimization of operating systems. for instance, the supply of waste plastics must be reliable as well as economically attractive compared with conventional secondary fuels such as heavy oil, natural gas and pulverized coal. In this work, we put special importance on the improvement of the combustibility of waste plastics as a way to enhance energy efficiency in blast furnace. As experimental variables to approach this target, the effects of plastic particle size, blast temperature, and the level of oxygen enrichment were investigated using a custom-made blast model designed to simulate a real furnace. Lastly, the combustion efficiency of the mixture of waste plastics and pulverized coal was tested. The observations made from these experiments led us to the conclusion that with the increase of both blast temperature and the level of oxygen enrichment, and with the decrease of particle size, the combustibility of waste PE could be improved at a given distance from tuyere. Also it was found that the efficiency of coal combustion decreased with the addition of plastics; however, the combustion efficiency of mixture could be comparable at longer distance from tuyere.

• Clean Technology
• /
• v.30 no.1
• /
• pp.37-46
• /
• 2024

Environmental problems caused by plastic waste have been continuously growing around the world, and plastic waste is increasing even faster after COVID-19. In particular, PP and PE account for more than half of all plastic production, and the amount of waste from these two materials is at a serious level. As a result, researchers are searching for an alternative method to plastic recycling, and plastic pyrolysis is one such alternative. In this paper, a numerical study was conducted on the pyrolysis behavior of non-condensable gas to predict the chemical reaction behavior of the pyrolysis gas. Based on gas products estimated from preceding literature, the behavior of non-condensable gas was analyzed according to temperature and residence time. Numerical analysis showed that as the temperature and residence time increased, the production of H₂ and heavy hydrocarbons increased through the conversion of the non-condensable gas, and at the same time, the CH₄ and C₆H₆ species decreased by participating in the reaction. In addition, analysis of the production rate showed that the decomposition reaction of C₂H₄ was the dominant reaction for H₂ generation. Also, it was found that more H₂ was produced by PE with higher C₂H₄ contents. As a future work, an experiment is needed to confirm how to increase the conversion rate of H₂ and carbon in plastics through the various operating conditions derived from this study's numerical analysis results.

• Analytical Science and Technology
• /
• v.12 no.1
• /
• pp.61-67
• /
• 1999

Two of municipal waste incinerators were selected as surveying facilities to research on the emission of dioxin and precusors. The sampling of flue gas and analysis was performed in the selected facilities. From the result, the emission patterns of dioxin and precusors, their relatership were examined. The toxic equivalency quantity(TEQ) of dioxin concentration was evaluated in two municipal waste incinerators. The 76.24% and 60.84% of total dioxin concentration in A and B incinerator were made up of the penta-, hexa- and hepta-chlorinated dibenzo-p-dioxin, respectively. Therefore, to reduce the dioxins in flue gas have to control the formation of furans. The chlorobenzenes and chlorophenols were analyzed in two incinerators. The 1,2,4,5-tetrachlorobenzene, penta-, and hexachlorobenzene are discharged and 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol are discharged mainly in A and B municipal waste incinerators.

• Polymer(Korea)
• /
• v.30 no.6
• /
• pp.486-491
• /
• 2006

Heterogeneous membranes were prepared by compression molding for the recovery of ammonium ion from waste water. Degree of sulfonation for sulfonated ion exchange resin increased with increasing amount of chlorosulfonic acid. It was 3.32 meq/g at 10 vol%. The tensile strength and elongation of the heterogeneous membrane was decreased with increasing contents of ion exchange resin. The tensile strength for LLDPE matrix membrane was the highest and also the elongation for EVA matrix membranes were the highest. The water content of heterogeneous membrane was increased with increasing contents of ion exchange resin. The maximum value of transport number for PE matrix membrane was 0.973. The electrical resistance of LLDPE matrix membrane was the lowest. It was value of $10.36{\Omega}/cm^2$ at 70 wt% resins.

• Current Research on Agriculture and Life Sciences
• /
• v.27
• /
• pp.29-33
• /
• 2009

Liquefied-wood polymer composite was prepared and mechanical properties was evaluated to develop potential utility of liquefied wood. The liquefied wood was made from waste wood and chemical modified with acetic anhydride and maleic anhydride (MA), phtalic anhydride (PA). The composite sheet was prepared from modified liquefied-wood and polymer(PE). The mechanical, chemical and microscopical properties composite sheet were investigated. The results were summarized as follows, 1. The tensile strength was increased and breaking elongation of composite sheet was decreased with the time of acetylation and the dosage of MA. 2. The Young's modulus of composite sheet was gradually decreased with the dosage of PA. 3. The peak intensity of 1737cm-1 in FT-IR spectra of chemical modified liquefied woods was increased. 4. The dispersity of liquefied woods with PE was improved with chemical modification.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.31 no.3 s.258
• /
• pp.403-408
• /
• 2007

The concrete pipe(Hume, PC) and polyethylene(PE) pipe are usually used for dram pipe in local market. Hume pipe, however, is heavy and needs the high cost of construction and PC pipe has a disadvantage to easily occur the deformation by the outside pressure even though it is light and constructible. The corrugated steel pipe coated with polyethylene is used increasedly because it is durable, constructible and economical. However, it is not used for sewage or waste water because it is hard to guarantee the watertight property on the coupling part. In this study, we studied on the flange coupling and the method of its construction to guarantee the watertight property and easy to use. If the developed flange coupling and method are used on a construction field, the economical property, constructible property and structural safety can be guaranteed.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.29 no.3
• /
• pp.153-161
• /
• 2023

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

• Journal of People, Plants, and Environment
• /
• v.24 no.2
• /
• pp.195-207
• /
• 2021

Background and objective: While response measures to particulate matters in rural areas are limited due to poor inventory record keeping in the agricultural sector, it is necessary to control agricultural waste vinyl and the emission of precursors released from open burning and the secondary generation of particulate matters. Currently, the open burning emission calculation method uses the definition prescribed in CAPSS by the National Institute of Environmental Research. Methods: This study presented an open burning emission calculation formula for agricultural waste vinyl, which is included as agricultural waste. As for activity data, the open burning ratio of agricultural waste vinyl, and the annual incineration volume provided in the Status Survey by the Ministry of Agriculture, Food, and Rural Affairs were applied. The emission factor was generated through incineration tests on three agricultural plastic film samples collected by the Korea Environment Corporation. Results: Among precursors, SOx and NOx were selected and their emission features were monitored with incineration experiment infrastructure based on the EPA 5G method. The highest emission concentration by agricultural waste type was concentrated in the first and second quarters. As for emission factor of SO₂, it was calculated at 98.25 g/kg for mulching-use LDPE, 52.31 g/kg for greenhouse-use LDPE, and 14.40 g/kg for HDPE. As for NOx, it was calculated at 18.21 g/kg for mulching-use LDPE, 16.49 g/kg for greenhouse-use LDPE, and 10.67 g/kg for HDPE. Conclusion: This test confirmed the incineration features of PE-based plastics, ascertained the SOx emission factor that had not been included in open burning in the past, and established that low NOx emission concentration is interfered by soil mixed with livestock excretions. The findings from this study are expected to contribute to improving the system for controlling air pollutants in rural environments.

• Journal of environmental and Sanitary engineering
• /
• v.18 no.3 s.49
• /
• pp.21-26
• /
• 2003

The generation of waste cable has been continuously increased as a production of electrical and communication media are extended. The current recovery methods, such as mechanical peeling, incineration, solvent extraction and pyrolysis, seems inadequate because they are either hard to apply in some cases or environmentally unacceptable. It has been shown that copper can be effectively separated from the jelly filled type cables using a soybean oil treatment method. As a result, jelly compound is vanished from the wire by soybean oil bath and waste wires are separated copper and PE by the mechanical chipper. This is a more environmentally friendly method than burning, and considerably faster than Stripping.