Ridder NoNa+, Installation And User Manual

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2.2.1 Purification (sodium removal)
During purification, sodium (and other monovalent ions) is removed from the drain
water. This is transferred to the wastewater. During this process, a tension field is
applied to the stack. This forces the ions to move through the membranes. This
contaminates the membranes.
To prevent (lime) deposits and to 'clean' the membranes again, the polarity is
reversed. The stack is now no longer being charged, but discharged. For more
information, see "Desalination box" on page 19.
The purification process is carried out in a cycle. The first time, the system initially
performs a short flush with fresh water to fill the wastewater tank. After that, the
purification process starts and this consists of the following stages:
1. Purification (charging stack)
2. Short flush with fresh water
3. Purification (discharging stack)
4. Short flush with fresh water
The purification process then starts over again, beginning with purification (charging
stack). When the water level in the wastewater tank reaches the high-water float, the
NoNa
+
receives a signal that it is time to empty the wastewater tank. See
"Discharging wastewater" on page 13.
Figure 2-2: Schematic diagram of purification process (charging stack)
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