RE:Innovative Electrostatic Deionization...OK, so they get the 85% water recovery, but they still have the captured ions in the water that is used when they reverse the polarity and flush them from the electrodes. So what happens to this "concentrated" flush water? Is it allowed to be flushed down the drain?
Nice to see a video explaining a bit of what is going on, more please.
Here are my jottings from the video:
John Motto, senior chemist
ESD - electrostatic deionisation, used to reduce water consumption
The unit is used to remove excess "limiters" from the leach water, return as much water as possible.
Ah "limiters" are chemicals (Sodium, chloride, carbonate and sulphate) they are in excess of requirements (from fertilizer) or excreted. As concentration increases, they decrease osmotic potential and impair ability of plants to take up water.
Pilot = 12.5 m3 /day = 1 acre of crops, Building on stage 1.
85% recovery target. The ESD system works on principle of capacitive deionisation. Capacitors are constructed of inexpensive carbon electrodes, energized by dc current. Positive ions attracted to negative electrode and vice versa.
Algae in leach water storage tank dealt with by site-specific pre-treatment, varying porosity in 6 cartridge filters and UV.
The ions bind to electrodes, so they have a finite capacity, thus efficiency reduces.
Regeneration - polarity reversed, ions repelled from electrodes and flushed in small water volume.
85% recovery is attainable.