The availability and security of water production using reliable energy recovery technologies

Abstract

The term availability can be defined as the probability of a system or piece of equipment, when used under the specified conditions, operates satisfactorily at any given time. The availability of the equipment installed in a seawater reverse osmosis (SWRO) facility is extremely important to the price, quality, and quantity of the final product—water. There are three critical components in the SWRO processes; the main high-pressure feed pumps, the reverse osmosis (RO) membranes, and the energy recovery device (ERD) system. The role that ERDs play is undeniably critical to the success or failure of an RO facility’s ability to produce and deliver water economically. The largest operating expense for an SWRO facility is the power consumed, which accounts for approximately 30% of the total RO operating expense. Typically for large facilities (>50,000 m3/d), the ERDs responsible for reducing energy consumption are only 1–2% of the entire initial capital cost—a small fraction—but one that can offer a substantial return on investment through energy savings. Selecting the proper ERD system can save millions of dollars over the life of a plant and provide owners and operators with a secure and reliable means of water production. This paper will focus on the economic benefits and importance of the availability of ERDs in SWRO desalination plants.