Spectra
Pure
®
Inc.
215 S. Industrial Drive, Suite 2A Tempe, Arizona 85281-2941 480.894.5437 Fax us toll-free 1.877.527.7873
Call us toll-free 1.800.685.2783 E-mail [email protected] Visit us on the web www.spectrapure.com
6
Theory of Operation: Water Production System
The storage tank (11) is a non-pressurized tank of any size. When water is withdrawn
from the tank to a point below the low-level fl oat (or pressure switch) (12), the input
solenoid (2) is activated by the Reverse Osmosis System Controller (27). When
suffi cient input pressure (as displayed on the input pressure gauge (4)) is sensed by
the input pressure switch (5), the main pump (6) and motor (7) are energized. Water
that has passed through the sediment fi lter (1) then fl ows through the low pressure
manifold (3). The pump increases the input water pressure in the membrane (8) to a
conservative 100 psi as displayed on the system pressure gauge (21).
The water is split by the membrane into two streams: a pure water stream (permeate)
and a waste water stream (concentrate). The pure water stream passes through the
product fl ow meter (10) and the TDS monitor (18) and then into the storage tank.
(The TDS Meter indicates the purity of the product water going into the tank and aids
in determining when the RO membrane may be failing.) The tank will fi ll until water
reaches the high-level fl oat (or pressure switch) (13). This will activate the fl ush cycle
(covered later) and then shut the pump and motor down.
The concentrate stream is split into two streams in the high pressure manifold
(20). One stream goes to drain through the capillary tube fl ow restrictor (22) and
concentrate fl ow meter (23). The other stream goes through the pressure regulator
(24). The pressure regulator is used to adjust the system operating pressure. The
output of the pressure regulator is feed back into the input water supplying the pump.
The fl ush cycle, initiated by the high-level fl oat (or pressure switch), opens the
concentrate bypass solenoid (25). This allows the concentrated waste water (as well
as any hardness or particulates that may have accumulated on the surface of the
membrane) to be rapidly fl ushed down the drain. After 45 seconds, the pump and
motor will spin down before the input solenoid is turned off, protecting the pump from
a starvation / cavitation condition. For the next six minutes, the pure water fl ush pump
(9) is activated, fl ooding the membrane with a pure-water bath until the fi ll cycle starts
over again.
