Waste Treatment and Immobilization Plant electrician Edi Sanchez assembles temporary heaters that will start up the first melter inside the plant’s Low-Activity Waste Facility at the Hanford Site.
Waste Treatment and Immobilization Plant electrician Edi Sanchez assembles temporary heaters that will start up the first melter inside the plant’s Low-Activity Waste Facility at the Hanford Site.

RICHLAND, Wash. – The weather isn’t the only thing heating up at the Hanford Site this summer, as staff at the Low-Activity Waste (LAW) Facility at the Waste Treatment and Immobilization Plant (WTP) are preparing to install 18 temporary heaters to start up the first of the facility’s two 300-ton glass melters.

The startup heaters will be installed through ports in the lid of the melter and will raise the melter’s internal operating temperature to 2,100 degrees Fahrenheit — hot enough to sustain the pool of molten glass to be used to start the waste vitrification process.

“This is an exciting and important step for our team as we drive toward melter heatup,” said WTP Project Director Valerie McCain, for contractor Bechtel National, Inc. “The melters are the heart of the Direct-Feed Low-Activity Waste (DFLAW) Program and bringing Melter 1 online is a significant milestone on our journey to begin treating tank waste.”

Temporary startup heaters rest in a storage rack as they are prepared for installation into a melter.
Temporary startup heaters rest in a storage rack as they are prepared for installation into a melter.

Heating up the melter is a complex process, consisting of a series of activities to prepare for and establish the pool of molten glass. After the startup heaters raise the melter to operating temperature, small glass beads called frit will be added until the pool covers the heating electrodes inside the melter.

After melter heatup, the startup heaters will be removed and replaced with bubblers to mix the molten glass pool and help maintain an even temperature. Finally, more frit will be added to the melter to bring the pool up to operating level. The melter will then be ready to receive simulated materials to test the system before processing tank waste.

During DFLAW operations, waste from Hanford’s large underground tanks that has been treated to remove radioactive cesium and solids will be fed directly to the LAW Facility’s melters. The waste and glass-forming materials will be mixed and heated in the melters, then poured into specially designed stainless-steel containers for permanent disposal at the site’s Integrated Disposal Facility.