
MEDICA - R200 US Version 01 08/14Page 7
3.2 Process Description
MEDICA - R200 US
•Feed water enters through a control valve (V1), and
through a particulate filter (FH1) into the inlet of the RO
pump (P1). Pressure in the pipework of the pump inlet is
monitored with a pressure switch (PSW1) to ensure that
the pump cannot run without sufficient water.
•P1 provides sufficient pressure and flow to the RO
module (M1). The RO concentrate flow is controlled
through a pressure relief valve (PRV2) or concentrate
flush valve (V3).
•Upon initial start-up, the system carries out a concentrate
flush to remove scale and debris from the membrane
surface to ensure RO performance is maintained.
•RO permeate water passes through:
•Temperature sensor (TS1).
•Water quality sensor (QS1), which measures the
conductivity of the water.
•RO permeate water is initially flushed to drain through the
overflow device until one of the following conditions
occurs:
•Minimum flush time is completed.
•Water quality is below set alarm point.
•4 minutes permeate flush has occurred. This will
result in an alarm condition that may be cleared
automatically as the RO performance improves.
•RO permeate water enters the reservoir through
permeate control valve (V2) and fills the reservoir until full
(350 liters). The RO system will only function if the level
in the reservoir is sufficiently low, less than 240 liters.
•When the reservoir contains 350 liters, the RO system
performs a further concentrate flush to reduce the
concentrate levels within the membrane housing and
reduce the possibilities of precipitation on the membrane
surface before going into stand-by.
•Water from the reservoir is distributed around the
installation at pressure (6 bar maximum) by the
recirculation pump (P2), controlled via the pressure-
sustaining valve (PSV1). An over-pressure switch
(PSW2) on the outlet of the pump will shut the system
down if operating pressures exceed 6 bar.
•Connections are available to incorporate a range of
cylinders containing water purification media, which
remove impurities and maintain water quality around the
system. The media can be selected to meet specific
requirements. Typically activated carbon and ion-
exchange media are used.
Any cylinders or additional equipment
installed (filters etc.) including ring
-
main pipework must be rated to the
operating pressure of the MEDICA
system (6 bar).