CWCO (Sawangan Desalination Project)
REVERSE OSMOSIS SYSTEM
The feed water passes through a replaceable 5-micron cartridge pre-filter which removes bulk suspended solids. Filtered water then flows to the inlet control valve. This solenoid-controlled diaphragm valve is wired to the ON/OFF switch and opens when the machine is turned ON, allowing water to flow to the pump inlet. When the machine is turned OFF, the valves close, preventing non-turbulent flow through the membrane elements and may lead to shorter membrane element life.
The pump feeds water to the membrane element housings arranged in parallel and serial combinations. The direction of water flow is indicated by an arrow on each membrane element housing. Water is separated by the membrane elements within the membranes and leaves the membrane element housings in two streams: permeate and concentrate. Permeate from each membrane element housing is collected in a common manifold. The permeate then flows through a flow meter and to the outlet point of the machine.
The concentrate leaves the last membrane element housing and flows to the flow control center (recycle/concentrate manifold). In machines with a recycle valve, the recycle valve channels a predetermined amount of concentrate into to pump inlet. Recycle increases recovery while maintaining adequate cross flow through the membrane elements. The other two ports of the flow control center lead to the concentrate valve and final pressure gauge. The concentrate valve has three functions:
It controls the amount of concentrate flowing to the drain.
It controls the pressure within the machine.
It helps control the system recovery.
In machines with Autoflush feature, an autoflush solenoid is added to the flow meter and to the outlet point of the machine to automate flushing during predetermined times. The schedule and duration of flushing are easily modified at the control panel.