Verification of product quality from process control---preliminary results

This paper describes how, using reasonable assumptions, a simple model for the West Valley Demonstration Project (WVDP) vitrification process can be constructed. Well-developed statistical ideas are then used to determine the consequences of the expected variations in process control variables, first in terms of glass product composition and then in terms of glass properties. Simple models for melt viscosity and glass chemical durability are presented and show how such models may be combined with the process model to verify product quality. The region most likely encompassing process variations is defined, and by requiring that this lies entirely within the region of acceptable glasses, we arrive at the present WVDP reference composition, WVW-RG4. To the extent that the assumptions described are valid, a point that will be tested at WVDP, it is concluded that the WVDP, as presently characterized, can successfully produce glasses that are both processible and of acceptable durability. Finally, the extensions and refinement of this work in progress are presented. 7 refs., 22 figs., 4 tabs.