Use of Paper Mill Waste in Ceramics Comparing Paper Mill Ash with Traditional Fluxes

1. Use of Paper Mill Waste in CeramicsComparing Paper Mill Ash with Traditional Fluxes Concept Compare paper mill waste material with common industrial minerals (fluxes) used to manufacture ceramic products. The “Ideal” Bottom Ash body composition exhibits behavior similar to the traditional dinnerware composition when observed using Hot Stage Microscopy. Experimental Results Ball mill dried waste to obtain the appropriate particle size. 20 hours in an alumina lined mill with 1¼” diameter spherical alumina media. Particle size distribution analysis. Bulk Chemical Analysis via ICP. Qualitative Phase Analysis. Powder X-Ray Diffraction method. Observe sintering/melting behavior via Hot Stage Microscope (HSM). 10° C/minute heating rate; 1300° C peak temperature. Chemical Analysis Chemical analysis results show that the paper mill ash has a much higher amount of “fluxing” oxides (Fe2O3, MgO, CaO) than traditional raw materials. The ash also has lower SiO2 and Al2O3 levels than traditional materials which must be adjusted for in the batch calculation (See below). The carbon content and LOI are also much higher for the mill ash (especially Fly Ash). This may cause problems with glaze bubbling, but only if it occurs above the glaze melting temperature. XRD on the ash samples show that the major crystalline phases present are Quartz (SiO2) and Calcite (CaCO3). The particle size distributions (PSD) of the milled bottom ash samples compare well with traditional ceramic raw materials (D50 = 10-15 µm). The Androscoggin ash has a smaller mean size due to a smaller and more uniform initial size distribution as received. Global Importance Decreased strain on the environment due to not needing to landfill the mill waste. Decrease in the cost of raw materials needed for ceramics manufacturers to produce quality products. * Industrial fluxes used in ceramic products General Observations The ash material shows potential to be substituted into ceramic products. The ash has a chemical composition that is compatible with ceramic products. The ash is a stronger flux than A-400, G-200, and K-200. The incoming ash waste must be ball milled to obtain a particle size similar to traditional raw materials (D50 = 10-15 µm). Melting Behavior “Ideal” Compositions “Ideal” Compositions containing the ash waste were calculated by replacing A-400 Nepheline Syenite with the ash material. The target body composition is based on a commercial dinnerware composition. The molar ratios of SiO2 and Al2O3 were kept at a constant flux (R2O + RO) level. The calculations are accomplished by converting the typical compositions to a molar basis and matching the molar levels of the oxides (R2O + RO). The other raw materials are then adjusted to keep the SiO2 and Al2O3 levels close to the original composition. Future Work Ball mill the Fly Ash waste to obtain the appropriate particle size. Determine surface chemistry and suspension behavior of the ash waste. Begin body substitutions using calculated “ideal” compositions. Determine physical properties of fired samples including; thermal expansion coefficient, mechanical strength, and microstructure characterization. Sintering plots obtained from the Hot Stage Microscope. The ash material melts at lower temperatures than traditional fluxes used in ceramic products. Utilization of Paper Mill Waste in Ceramic Products Todd Kulis • David Earl Funding: United States Environmental Protection Agency New York State College of Ceramics · Alfred University Center for Environmental and Energy Research – May2003