A graphic representation showing how the 242-A Evaporator creates storage space in the double-shell tanks at the Hanford Site.
A graphic representation showing how the 242-A Evaporator creates storage space in the double-shell tanks at the Hanford Site.

RICHLAND, Wash. – EM’s Direct-Feed Low-Activity Waste approach will rely on many Hanford Site facilities working together.

The 242-A Evaporator is one of those facilities, which is why ensuring its dependability is a top priority.

The 242-A Evaporator is fundamental to the Hanford Site tank waste mission. EM Office of River Protection (ORP) and contractor Washington River Protection Solutions have completed several major upgrades and repairs at the evaporator, and more are planned.

“These improvements will ensure the evaporator is efficient and dependable for its long-term mission during tank waste treatment operations,” said Paul Hernandez with ORP.

The control room of Hanford’s 242-A Evaporator facility has been upgraded to support the Hanford Site tank waste treatment mission using the Direct-Feed Low-Activity Waste approach. Other upgrades will include adding new waste transfer lines.
The control room of Hanford’s 242-A Evaporator facility has been upgraded to support the Hanford Site tank waste treatment mission using the Direct-Feed Low-Activity Waste approach. Other upgrades will include adding new waste transfer lines.

The evaporator has played a vital role for more than 40 years, creating storage space in Hanford’s double-shell tanks by boiling liquid tank waste to remove water and most volatile organics, reducing the volume by as much as 40%. Vapor from the boiling waste is condensed, filtered, and sent to Hanford’s Effluent Treatment Facility for disposal. The remaining slurry is sent back to a double-shell waste tank.

Recent improvements include a new instrument air dryer and a new air receiver tank and piping.

The team also upgraded the facility’s monitoring and control system, updating system hardware and software, and improving cybersecurity.

WRPS recently completed the design for replacing three waste transfer lines. Double-walled piping is used to move tank waste from double-shell tanks to the evaporator for reduction and to send the resulting slurry back to a tank.

Slurry lines installed in 1977 were taken out of service in 2018 after the lines failed periodic pressure testing of the outer encasement piping. While the inner piping that transfers waste has not leaked, the encasement line integrity could not be verified. EM decided to install three new lines, one to transfer tank waste to the evaporator, one to return slurry back to the tank, and a backup line.

Other improvements will include a safety system upgrade that will significantly increase the efficiency of equipment testing required prior to an evaporator campaign.