report
2.2.3.4.1 Water use in agriculture

1.3.4.1 Water use in agriculture

Considering the volumes of wastewater produced by farms on a continual basis, any technology for remediation and purification will need to be capable of dealing with large volumes and be cost effective.  Clays, and more recently nano clays, are one such class of material.  These have demonstrated ability to filter and bind to a variety of toxic substances including pesticides, either on their own or as part of a complex with other chemical species[i]^,[ii]. They are also relatively inexpensive, requiring little processing from the excavated clay.

Remediation of contaminated water can be achieved through photocatalytic breakdown.  Using titanium dioxide nanoparticles (another relatively inexpensive material) a number of research groups have demonstrated degradation of a variety of agrochemicals by passing contaminated/waste water over filters coated with TiO2 nanoparticles and exposed to normal daylight conditions[iii].  Field trials are currently underway in Canada to investigate the efficacy of large transparent and porous tubes containing TiO2 to photocatalyse the degradation of chemicals in ground water, by sinking these into bore-holes[iv].  Requiring no external energy supply, these have potential to be used throughout the world.