GE Merlin Application Manual

Also see for Merlin: Installation and maintenance manual Installation and maintenance manual Installation and maintenance manual

Contents

20 MEMBRANE LIFERev CMEMBRANE LIFEThe Merlin uses a new, patented, RO membrane technology, not an ultraor nanofiltration membrane.It is a standard thin film membrane (TFM) style that is not tolerant ofchlorine.Maximizing Membrane Element LifePretreatment is the key to maximizing the Merlin membrane element life,like all reverse osmosis membranes. To maximize element life, adhere tothe following inlet water conditions.Chlorine at inlet to element — 0 ppmInlet hardness to system — less than 10 grain, 0 grain optimalInlet iron to system — less than .1 ppm, 0 ppm optimalInlet manganese — less than .05 ppm, 0 ppm optimalTemperature — 40 to 100°F (4.4 to 37.8°C)MERLIN RECOVERY VS. EFFICIENCYOne performance measure for a home RO system is the recovery/efficiency rate. This is a published amount of permeate water produced asa product of total inlet water used. The higher the recovery of an ROmembrane system, the less waste water is sent to drain.• Recovery is the measured permeate (product) water volumeproduced as a percentage of inlet water consumed. This ismeasured directly from the membrane element.• Efficiency is the measured permeate (product) water volumeproduced as a percentage of inlet water consumed.But,Efficiency is measured taking into account the complete system. Thismeasurement includes the storage tank and any other pressure dropin the system.Efficiency is the real-world performance that the consumer willexperience. Therefore it is the best measurement of system performance.The Problem With Systems That Have Storage TanksTraditional home RO systems that utilize a tank may be able to boast 18-25% recovery, however, most operate at much lower efficiency.As storage tank systems produce permeate water, the tank exertspressure drop on the membrane as the tank fills and tank pressureincreases. This pressure drop decreases the membrane elements recoverysignificantly as the tank fills. In many cases, the system’s efficiency willdrop as low as 5% when the tank is near full.