Dissection is didactic. Beyond the formaldehyde-soaked forays of biology class, dissection is a valuable workplace tool. In fact, for facilities managers, a simple post mortem exploration of filtration equipment can help identify and diagnose critical system issues and reveal valuable insight. Membrane Autopsies Assess Long-Term Performance, a white paper recently published by the American Water Works Association, recommends performing periodic membrane autopsies to evaluate performance and external factors that may be affecting micro- and ultra-filtration.
According to authors Charles Liu, Jesse Campbell, and James Moy, a properly planned membrane autopsy includes a visual inspection for cracks or damage, solids deposits, and discoloration. It also involves integrity and permeability testing, a surface analysis and a cleaning study, as well as tensile strength trials and operational reviews of system changes and cleaning logs.
“Looking closely at a membrane offers a micro-scale glimpse of what’s happening on a much larger, plant scale,” explains Mike Snodgrass, Membrane Technology Leader for Ovivo. By evaluating changes in the mechanical and physical properties of a membrane, plant operators can diagnose potentially grave, systemwide issues and take preventative action to mitigate future fouling.
There’s no critical need for an autopsy if the system is performing to design specifications, according to Snodgrass. But if a facility manager has any suspicions that something is fouling the membrane, it’s a wise idea to send it for an autopsy, especially if performance has declined significantly. “An autopsy can provide you with valuable diagnostic data to identify problems and potentially make a system run more efficiently.”
Armed with indicative information, the facilities manager can then make educated decisions and determine a proactive, systemwide action plan. Notice microbial growth? A tiny chlorine addition may inhibit it. Detect a film of grease or oils on the membrane? Perhaps a grease trap upstream is the culprit. As the authors of the aforementioned study explain, the insight provided by membrane autopsies is invaluable. And there are a growing number of resources to support your diagnostics.
Do you perform membrane autopsies?