BMB Technology Nova Pro, Инструкция по установке, эксплуатации и обслуживанию

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Reverse osmosis Membrane- filters 4 & 5 Total - 600 GPD
At the heart of every Reverse Osmosis system is the membrane filter’s. The membrane filter
consists of microporous, semipermeable membrane sheets. The sheets are glued to each
other around three edges with a thin spacer in between (prevents the sheets from sticking to
each other) to form a “leaf”. Next, depending on the desired capacity of the membrane filter,
multiple leaf’s with mesh spacers in between (to allow the water to pass between leaf’s) are
stacked on top of each other. The stack is then spirally wound with the open end of the leaf
adhered to a perforated tube that runs up and down the center.
The membrane is constructed in this manner because unlike the pre-
filters which are
designed as “dead - end filtration”, Reverse Osmosis membranes are designed as “crossflow
filtration”. In dead - end filtration, the feed water is passed perpendicular to the filter surface in
order to trap large particles. However , in Crossflow filtration the feed water is passed
tangential to the filter surface so the more -concentrated solution (particles) exits at the end
of the filter while the less - concentrated solution (purified water) permeates through the
membrane surface, gets trapped between the sheets and exits out of the perforated tube.
Figure 4 below shows the difference between dead - end filtration and crossflow filtration.