I’ve seen lots of water treatment technologies over the last fifteen years consisting of almost every conceivable variant of nanotechnology, from electrospun nanofibers to graphene. Some of them are great, but many won’t succeed, for a simple reason that is obvious to anyone outside the science community.
Hardly a week goes by without some new form of graphene being promoted as the answer to the world’s water problems, followed by a deafening silence from the water industry. The reason for the overall lack of enthusiasm is something well understood by accountants but not nanotechnologists, ‘annualized capital costs.’
For a typical sea water desalination plant – typical as there is a lot of variation in the capacity of the plant and the salinity of the water which in turn affects energy use – the two biggest costs are capital, i.e. the financing of the plant and its infrastructure, and energy.
Most new technologies claim to be able to reduce energy requirements, but unless they are delivered as a spiral or flat sheet membrane compatible with existing infrastructure then they will struggle to get traction. Adding a significant amount to the ongoing annualized capital costs by requiring different pumps, filters and plumbing will always get a thumbs down from a finance director.
One of the things that attracted me to G2O’s technology was that the graphene coating is applied to existing membranes as a final step. While the dimensions of the membrane may change by a few nanometres to generate performance increases of up to 100 times, it’s not enough to prevent treated membranes from being used in standard filer modules.