Understand the feed water
Reverse osmosis and nanofiltration use membranes to separate treated water from a concentrated stream. Their suitability depends on the contaminants to be addressed and the water quality required.
Consider the whole system
Technology selection should consider pretreatment, energy requirements, membrane fouling and the handling of concentrate. Comparing those requirements is more useful than choosing a process from its name alone.
Ask the right questions
Define the target water quality, characterize the source and compare practical operating needs. This editorial guide introduces general principles; a site assessment is needed before specifying equipment.