Waste Treatment Plant Facility Completes Exhaust Treatment Testing

RICHLAND, Wash. – Workers at the Hanford Site’s Waste Treatment and Immobilization Plant (WTP) have completed critical testing of the exhaust treatment system, or offgas system, in the Low-Activity Waste (LAW) Facility.

This testing demonstrated that offgas system air valves will function as designed during an abnormal event, such as an unexpected power loss during plant operations. During events such as a power loss, it is necessary to maintain safety systems, like the offgas system, that protect the LAW Facility from hazardous gases generated by the melter during vitrification, when radioactive and chemical waste are mixed with glass-forming materials.

“The entire team worked through a number of challenges to finish the testing," said Rick Holmes, general manager for Waste Treatment Completion Company, a subcontractor to project lead Bechtel National, Inc. “We had great support from our plant engineering teammates, the plant management completions team and operations staff located in the control room."

During vitrification, the LAW Facility offgas system will filter, clean and scrub melter exhaust to ensure worker, public and environmental safety. Melter exhaust will be treated to remove particulates, mercury, nitrogen oxides, volatile organic compounds and acid gases.

During Direct-Feed Low-Activity Waste Program operations, waste treated to remove radioactive cesium and solids at the Hanford Tank Farms will be fed directly to the LAW Facility’s melters. The waste and glass-forming materials will be mixed, heated to 2,100 degrees Fahrenheit and poured into specially designed stainless-steel containers. The containers will then be transported to the site’s Integrated Disposal Facility.