According to Hal McCune, spokesman for URS, the company contracted to conduct chemical weapons destruction at the Umatilla Chemical Depot, there was serious doubt whether the company could meet the April 2012 deadline for chemical weapons destruction.
We had kind of a rough start, McCune said.
The trouble stemmed from the heel left in mustard agent ton-containers, a caked mass of hardened agent that settled into the bottom of containers. It's not unlike paint that settles in old paint cans.
According to McCune, liquid mustard agent is run through a liquid incinerator furnace while the ton-containers are sent to a metal parts furnace.
The issue is what to do with the agent heel. Historically, the heel was broken up with high-pressure hot water into a rinsate mixture, then put into ton-containers and sent to the metal parts furnace.
Regulations limit the amount of rinsate per ton-container that can be burned in the metal parts furnace to about 40 gallons. McCune estimated that process would nearly double the number of ton-containers needed to complete mustard agent destruction to just over 5,000.
At that point, we said 'what can we do to speed up the process?' McCune said.
Enter the rinsate collection system, the first system of its kind to be used in a demilitarization facility. The system eliminates the need for extra ton-containers by piping the rinsate to the liquid incinerator, which can process higher volumes of material.
Processing rinsate in our liquid furnace made more sense, said John Jackson, the closure engineering manager.
The system required a combination of novel approaches and repurposing existing technology to get up and running, a process made more difficult by the need to wear protective suits during construction.
Additionally, the system had to be able to withstand hydrochloric acid, a byproduct of the rinsate process. According to Jackson, the pipes are lined with teflon, and the system's filters had to be made from titanium. Even the rinsate storage tanks had to be constructed of special alloy.
Once up and running, McCune estimates the rinsate collections system has pumped 165,228 pounds of rinsate to the liquid furnace, saving two months of destruction already.
This really gives us the breathing room we don't have to worry about it, McCune said.
According to Jackson, other demilitarization projects, including those in Pueblo, Colo., and Bluegrass, Ky., are looking at the rinsate collection system and trying to learn from the UMCD.
It is technology we're able to share, Jackson said. They're using some of those lessons learned.