Reliability and availability assessment of reverse osmosis

This research work assesses the performance of reverse osmosis (RO) plants in the Arabian Gulf region by analyzing its failure behavior and downtime p atterns. The data collected are from an experimental RO plant in the region ; these data cover a 4-year operation of the plant regarding the failures o f several components and subsystems of the plant. Since the plant was desig ned for continuous operation, assessment of the availability of the plant w as considered to be more appropriate than that of reliability. For the purp ose of assessing availability, the plant was divided into four subsystems: beachwell pumps, pre-treatment; RO, and post-treatment. Subjective assessme nt of failure probabilities of subsystems was made wherever detailed data w ere not available. The overall unavailability of the RO plant was 0.95 d/y.