As part of Water Resources’ Chemical Injection system for providing the cooling water to the site, sulfuric acid is injected into the CW canals at each unit to the control ph levels. The sulfuric acid is stored in large tanks (2 tanks at each CW canal, “A” and “B”). Over time, these large tanks deteriorate or corrode from the inside out and need replacement. This work has approximately 4.5-month windows, excluding scheduled refueling outages that fall within those timeframes. A major portion of this work scope involves replacing two acid tanks for each unit, several hundred feet of stainless-steel pipe, and all associated valves and fittings.
APS Water Resources’ Facility Acid Tank Replacements Unit 2 and Unit 3
The Challenge
A valuable lesson learned from the first phase of this project was noted in the planning. The lead time for specialty valves was identified early on as being 9-weeks long.
The Solution
Our team quickly went to work developing a contingency plan to reinstall the old valves in order to allow time for the new equipment to arrive.
The Result
Plant engineering approved this method and the work was completed safely and on time.