Enhanced butterfly valves help plant in Runcorn, United Kingdom, avoid six unplanned shutdowns and save an estimated $600,000 USD.
MARSHALLTOWN, IOWA (January 18, 2011) -- INEOS Chlor, a major European producer of chlor-alkali and chlorine derivatives, reduced process variability by 5% at its plant in Runcorn, United Kingdom, by replacing traditional butterfly valves with Fisher® Control-Disk™ valves from Emerson Process Management. The reduced variability enabled the plant to increase throughput, avoid several unplanned shutdowns that could have cost as much as $600,000, and achieve a 96% Overall Equipment Effectiveness rating for the unit where the valves were installed.
“For a plant this size, even a modest reduction in variability can have a significant payback," said Barry Makepeace, INEOS Chlor control & instrumentation engineer. "The Control-Disk valve applications not only saved us money, but also enabled us to optimize process control without sacrificing flow capacity or needing to re-pipe.”
The Runcorn plant had previously used traditional butterfly valves to control the temperature and flow of cooling water to the primary condensers. Tight control is essential because if the condensers’ temperature is too low, there will be residual chlorine in the system, which has to be removed. If the temperature is too high, there is an increased risk of a safety trip or plant shutdown. Each trip and subsequent unplanned shutdown can cost INEOS Chlor up to $100,000 USD.
Unfortunately, the traditional valves had a small control range and a large deadband, which reduced their ability to respond to temperature changes. In the previous 12 months, the plant had experienced 23 trips leading to a significant loss of production.
Working with Emerson valve experts, INEOS Chlor replaced four traditional butterfly valves with the new Fisher Control-Disk design. Its effective control range (15% to 70% of travel) approaches that of a segmented ball valve. Tighter, more reliable valve control enabled plant operators to optimize temperature set points and avoid at least six unplanned shutdowns—saving the plant up to an estimated $600,000.