Process Development cont'd

DOE-HDBK-1132-99

these specifications address the chemical composition, radionuclide inventory,

product consistency, phase stability, and hazardous waste. Additionally, the

specifications provide requirements for the high-level waste Canisters and

Canistered Waste Form.

The behavior of the target composition in the melter and its compatibility with

the technology addresses the issues of foaming, melt rate, precipitation of

metals, viscosity, mixing behavior, temperature, and corrosiveness. Because

these issues relate to melter technology, they represent the practical aspects

of preparing an acceptable glass in compliance with regulations, given the

technology.

Development of the process for manufacturing the final waste glass product

involves generating data associated with the behavior of the various feed

streams. Data required to develop predictive models can aid in product and

production control. Data for models include pH, viscosity, rheology, off-gas,

and redox.

Typically, the development program should follow a strategy of--

identifying various sets or families of potential glass target compositions

that meet regulatory specifications;

identifying and further developing a subset of glass target compositions

that will be compatible and processable through a melter;

choosing a preferred or reference composition on which front-end

process development and control schemes are developed.

The strategy uses a combination of laboratory crucible testing, small melter

scale-up, and full-process scale-up to obtain data and develop empirical

relationships necessary for predicting process behavior and glass product

performance.

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