• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.469-477
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• 2021

In this study, the mechanical property of anti-fouling coating using CNF was evaluated to prevent the durability and stability of structure exposed the marine environment. Anti-fouling coating using CNF was prepared by CNF, AKD and waste glass powder, and contact angle test, drying time, viscosity analysis and microstructure were performed. When coating on one number of times, It was showed to relatively high hydrophobic performance in steel. And It was confirmed that the contact angle increased as the content of AKD increased in cement mortar. When coating on three number of times, the surface was confirmed super-hydrophobic at maximum of 151.6°. When mixing waste glass powder, the surface was showed to relatively high hydrophobic. It is pseudo plastic fluid when CNF and distilled water were prepared in a ratio of 1:1, And Anti fouling coating is judged to be suitable for use as coating on marine structure.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.382-390
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• 2013

Foaming process of waste soda lime glasses by just chemical composition control of vitreous feed materials was investigated to find a novel and efficient recycling process. For the chemical composition control of feed materials, 10 wt. parts of $SiO_2$, 0.5 wt. parts of $Na_2SO_4$, 3.0 wt. parts of $B_2O_3$, and 0.3 wt. parts of carbon black as the foaming agent were mixed with 100 wt. parts of soda-lime vitreous feed powder. Proper conditions for foaming process in tunnel kiln are the foaming temperature of $830{\sim}850^{\circ}C$, the foaming time of 30~35 min, and the vitreous feed powder particle size of -325 mesh. Properties of foamed glass blocks obtained under these foaming conditions showed the density of $0.17{\sim}0.21g/cm^3$, thermal conductivity of $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, moisture absorption of 1.1~1.5%, and compressive strength of $20{\sim}30kgf/mm^2$.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.1
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• pp.23-28
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• 2009

There is several ways of recycling methods for waste FRP boats. The main one is mechanical recycling that is one of the simple and technically proven methods. It recently has been reported that FRP can be recycled by separating into laminated glass fiber layers instead of crushing into powder. Even though the mechanical recycling is a good way for the eligibility of laminated glass fiber reinforced material, the system should have another option which can collect resin of FRP. Because the resin is still very useful renewable energy source, that cannot be discarded, But FRP is made up of laminated glass fiber(roving cloth layer) which is fire retardant substances and very hard to break into each layer. Due to the high cost of fossil energy the waste plastics should be regenerated to the source of renewable energy. Laminated glass fiber which is recyclable in a very limited way, is currently a serious barrier to waste FRP boat regenerating. This study is to propose a new extracting method which is efficient and environment friendly FRP waste regenerating system. The recycled glass fiber which is obtained by the separation of the roving layer from FRP waste has been found to be useful for concrete(FRC) products or concrete(FRC) structures as fiber reinforced material. And it can be successively applied to renewable energy applications using the waste resins of FRP residue without laminated glass fiber.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.1
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• pp.50-54
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• 2008

There are several basic classes of recycling methods for FRP boats. The main one is 'Mechanical recycling' which involves shredding and grinding of the scrap FRP in a new product. That is one of the simpler and more technically proven methods. It recently has been reported that FRP can be recycled by separating into layers instead of crushing into powder. Many researchers should be more interested in these mechanical recycling for the eligibility. Nevertheless, because resins is very useful renewable energy, most of waste FRP regenerating methods depend on incineration (reclamation) or thermal recycling (pyrolysis). FRP is made up of laminated glass- fiber (roving cloth layer) which is also very unlikely to break into each layer. If there is an extracting method which is efficient and environment friendly removing glass fiber from waste FRP, it should also solve the another urgent problem. Laminated glass-fiber which is very limited renewable, is a serious barrier to wast FRP boat regenerating. This study is to propose a new extracting method which is efficient and environment friendly waste FRP regenerating system. And it should be applied to renewable energy applications with the waste resins of FRP. Also recycling glass fiber obtained by the separation of the roving layer from waste FRP will be consider to be useful for concrete products or structures.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.1
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• pp.42-45
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• 2008

It has been reported that FRP (fiber reinforced plastic) can be recycled by separating into layers instead of crushing into powder. F-fiber obtained from roving layer separated from FRP, has bigger tensile strength than the bundle of glass fibers of which FRP was made (more than 90%). SEM image of F-fiber shows the presence of some resin. Under the proposition of usage of F-fiber in the concrete material, tensile strength is examined after soaking in a basic solution (NaOH+KOH). The reaction mechanism of strength loss may be considered as an attack of hydroxide ion ($OH^-$) on a chemical bond of Si-O-Si of glass fiber. The simulation graph of the strength loss data implies certain reaction mechanism. While in the early stage kinetically controlled reaction results in a fast drop of tensile strength, after 30 days dispersion rate of hydroxide ion plays a major role in strength loss. This result is similar to the one for the AR glass. An extrapolation of the graph would make an assumption about the lift time of F-fiber possible.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.49-55
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• 2012

In this paper, the physical properties of lightweight aggregate such as density and water absorption according to addition ratio and type of flux were investigated. When using $Na_2CO_3$ as flux of lightweight aggregate, burnability was available at low burning temperature and water absorption increased. And as increasing addition ratio of $CaCO_3$, NaOH, $Fe_2O_3$, absorption decreased and $CaCO_3$, NaOH, $Fe_2O_3$ were considered improper to use flux of lightweight aggregate because of high dried density. $Na_2SO_4$ was proper to use flux of lightweight aggregate due to dried density $1.35{\sim}1.50g/cm^3$ and lower absorption. When using glass abrasive sludge as flux of lightweight aggregate, dried density and water absorption were in the range of $1.45{\sim}1.55g/cm^3$ and 9~12% respectively. It was indicated that as increasing addition ratio of blast furnace slag powder, density increased whereas absorption decreased. In use of oxidizing slag as flux, artificial lightweight aggregate which have dried density $1.46g/cm^3$, water absorption 8,5 % can be manufactured at 10 % of addition ratio.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.35-41
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• 2023

In this study, silicon sludge generated in semiconductor manufacturing process is recycled and applied as materials for pigments and paints. In detail, metallic impurities are removed from silicon sludge to obtain plate-like silicon sludge powder (SW-sludge), which is then coated with titanium dioxide via sol-gel method (TCS-sludge). SW-sludge and TCS-sludge are dispersed in hydrophilic transparent varnish and sprayed onto glass substrates to observe the possibility for the application as materials for pigments and paints. Notably, the applicability of TCS-sludge-based paint is improved compared to SW-sludge-based paint after the titanium dioxide coating. Moreover, the color of TCS-sludge-based paint turns into white. Accordingly, it is confirmed that the applicability and hydrophilicity are improved by the presence of outer titanium dioxide layer. In this regard, it is expected that the recycled TCS-sludge may be a future material for the application as pigments and paints.