A New Recycling Process of Waste Glass Wool Using Pyrolysis with Sodium Hydroxide

Abstract

Abstract—Glass wool insulation consists of glass fibers and phenolic resin as a binder to be a texture similar to wool, resulting in high thermal insulation properties. A large amount of them were used for energy conservation of buildings, and recently disposed at landfill sites to be pressured because of large volume to mass. In this study, we attempted to convert resin and glass fiber in the waste glass wool into gas and water glass using sodium hydroxide reaction, respectively. Waste glass wool was cut, sample peace (1 g) and sodium hydroxide (1 – 3 g) put into the reactor, and the reactor was heated with an electric furnace while flowing nitrogen (50 mL/min). After heating to setting temperature (400 550 oC) for 1 – 30 h, the reactor was naturally cooled to room temperature. The generated gas during the reaction was collected by gas pack. After cooling, the residue inside the reactor was washed with nitric acid, filtrates to obtain the residual substance, and silica concentration in the filtrate was measured to calculate the silica extracted content from waste glass wool. By using pyrolysis with sodium hydroxide, waste glass wool can be decomposed by converting the resin into the gases, such as hydrogen and methane, and glass fiber into soluble salt to be extracted into the solution. Waste glass wool can be decomposed by pyrolysis with 3 times weight of NaOH to the sample above 400 o C for 1 6 h.