Development of a New Feed Channel Spacer for Reverse Osmosis Elements

Although major advances have been made in membrane transport properties during the last 20 years, spiral-wound element construction has remained virtually unchanged. Element suppliers have continued to use a 31 mil thick feed channel spacer, first pioneered by DuPont in the mid 1960\'s. There is continuing evidence that this mesh spacer configuration is a major contributor to membrane fouling by forming "dead areas" of low flow behind the spacer segments which trap the foulants. During cleaning operations, these foulants may be loosened from the membrane surface but cannot be flushed out of the element. The fouling materials remain trapped within the mesh spacer and redeposit on the membrane upon repressurization, thereby obviating the effects of the effects of the cleaning operation.