Mobile water system deployed during power plant upgrades in rural Alaska
Golden Valley Electric Assn. (GVEA), a not-for-profit electric cooperative in the Alaska Interior, runs a two-unit coal-fired power plant in Healy, Alaska. A major power source for Alaska with 3,177 miles of transmission and distribution line, if this plant were to fail, it would spell disaster for the 100,000 people who rely on it daily. So, when GVEA decided to upgrade the Healy plant’s environmental controls and systems, along with its water treatment system—all while bringing a second, larger power plant back online—it became critical to find a temporary water treatment solution to keep the plant up and running.
In August 2014, GVEA contacted the GE Water & Process Technologies team. With a second power plant coming online and its current water treatment system in need of an upgrade, the Healy plant would be temporarily offline. Already familiar with GE due to a 10-year relationship with its chemical solutions team, GVEA reached out to the mobile water (also known as temporary or outsourced water) team. The North America mobile water team has a fleet of more than 600 pieces of deployable mobile equipment and technology to support ion exchange, filtration and membrane separation, including ultrafiltration and reverse osmosis (RO), which is where GVEA had a need.
On the Road Again
Healy is located approximately two hours from the city of Fairbanks and 300 miles south of the Arctic Circle. It is known for long, cold winters, summer temperatures at the freezing mark, and snow on the ground for most of the year—not a hospitable environment for a road trip. But, in March 2015, that is just what the GE team did.
The team had originally planned to ship its equipment to Healy via barge, which would usually take a maximum of two weeks from ship date to arrival date. A major dockworkers’ strike in the western U.S., however, meant that all of GE’s usual freight companies were no longer reliable from a resource and delivery time frame perspective—a less-than-ideal situation for both GVEA and GE. As a result, and after much discussion, a last-minute decision was made to truck the equipment from San Jose, Calif., to Healy—a journey of approximately 3,100 miles, in the middle of winter, close to the Arctic Circle.
As you might imagine, this was quite an adventure for the mobile water team, and included snow, ice and a few wild bison crossings. The trip has become a favorite of the team leadership, and is a major source of pride for the team, demonstrating its ability to deliver temporary water solutions to even the most remote locations.
The GE system at Healy included an RO trailer containing various filtration vessels and a 100-gal-per-minute RO unit. The product water from the RO system was further purified by ion exchange tanks to attain the quality necessary for boiler feedwater. To minimize replacement and shipment of the ion exchange tanks, which can be costly, the RO system included an internal product water recycling system. Equipment was expected to be on site for 90 days. Because of the remote location, a GE representative has been on site eight to 10 hours per day at least five days per week since the project began to speed up service response time, just in case an issue occurs.
According to Lynn Thompson, vice president of power supply for GVEA, access to clean water for the Healy plant was a crucial step in supporting its ongoing investment, upgrading environmental controls and replacing older equipment to achieve a successful restart.