Schedule Unclear for Resuming IWTU Startup Tests
WC Monitor
4/24/2015
As new details have been made public on the latest set of technical issues experienced during startup efforts at the Idaho Integrated Waste Treatment Unit, the Department of Energy is staying quiet on whether additional time may be needed before testing efforts can resume. The IWTU is currently in an outage period that began in January after undergoing an initial round of testing using a waste simulant. DOE had initially anticipated the outage being completed in April, and then shifted the schedule to May following the discovery of what the Department described as “unexpected equipment conditions.” DOE declined to comment late this week as to when the outage is currently expected to be completed. “The facility is currently being modified to improve operational performance in preparation for the next simulant run. This work has taken additional time to accommodate vendor reviews and updates to facility engineering, safety and operational documentation. Simulant testing will resume once the modifications are complete,” Danielle Miller, a spokeswoman for the DOE Idaho Operations Office, said in a written response.
DOE Details Latest Set of Technical Issues in CAB Presentation
DOE provided more detail on the issues being addressed during the current outage period in a presentation to the Idaho Citizens Advisory Board earlier this month. Such issues include the discovery of a “bark like” formation in the IWTU’s Denitration Mineralization Reformer, which is the first of two fluidized beds in the IWTU steam reforming process. “Chemical analysis under way to determine chemical reaction forming bark leading to changes in DMR bed material and additives,” the presentation says.
Other issues being addressed, according to the presentation, include problems with the DMR Auger Grinder, problems with the facility’s off-gas blowers and erosion of the refractory lining of a facility component. In addition, an evaluation of the pressure relief system has resulted in a lower feed rate of material into the DMR, according to the presentation. “Engineering designs are being installed to upgrade the pressure relief system on the two vessels affected,” the presentation says.
Facility Now to Begin Processing Waste by Next Fall
The IWTU is intended to treat approximately 900,000 gallons of liquid waste that remains at the Idaho site through a steam reforming process for disposal and to allow for closure of the site’s remaining waste tanks. In recent years, efforts to get the facility in full operation have been bedeviled by a number of technical issues, one of the most significant of which was a pressure event that occurred in the summer of 2012 when the facility’s filters became clogged with carbon material during efforts to get it up to its operating temperature. The IWTU also experienced a set of equipment issues last spring and summer that resulted in a series of outages lasting weeks in duration.
DOE had initially committed to the state of Idaho to have the remaining liquid waste at the Idaho site treated by the end of 2012, and then by the end of 2014. Under a new schedule recently reached with Idaho regulators, the Department now has committed to initiating waste treatment at the IWTU by Sept. 30, 2016; and to have the four remaining waste tanks at the Idaho site removed from service by Dec. 31, 2018.
