Rinsate collection system speeds mustard agent destruction

The installation of a rinsate collection system at the Umatilla Chemical Depot in Umatilla, Oregon, has sped up the process of incinerating its remaining stockpile of mustard agent.

Before the system’s introduction, Hal McCune, a spokesman for URS, the company contracted to run the destruction process, had serious doubts about whether or not they could reach the April 2012 deadline to complete the work, according to HermistonHerald.com.

“We had kind of a rough start,” McCune said, HermistonHerald.com reports.

The trouble came primarily from a caked mass of hardened mustard agent that settles at the bottom of the ton containers that are used for storage. Known as the heel, the substance is not unlike paint that settles in the bottom of paint cans.

The heel is usually broken up with water from high pressure hoses and formed into what is called a rinsate mixture. The rinsate is then put back into the ton containers for incineration.

Regulations limit the amount of rinsate that can be incinerated in the ton containers to approximately 40 gallons. McCune estimated that the operation at Umatilla would require double the number of ton containers needed to take care of the material at 5,000.

“At that point, we said 'what can we do to speed up the process?'” McCune said, HermistonHerald.com reports.

URS decided the best way to deal with the situation was to build a rinsate collection system, the first of its kind to be used in a demilitarization facility. The system operates by pumping the leftover rinsate into the liquid incinerator, eliminating the need for extra ton containers.

“Processing rinsate in our liquid furnace made more sense,” John Jackson, the depot's closure engineering manager, said, HermistonHerald.com reports.

To get the system up and running required new approaches and a repurposing of existing technology, a process made more difficult because workers needed to wear protective suits during the system’s construction.

The system also had to be able to withstand hydrochloric acid, a byproduct of the rinsate process. Its pipes had to be lined with teflon, and the system’s filters had to be constructed from titanium.

According to McCune, the system has already made a huge impact by pumping 165,228 pounds of rinsate into the liquid furnace, saving two months of time.

“This really gives us the breathing room," McCune said, according to HermistonHerald.com. "We don't have to worry about it."