A new study claims that the use of graphene filters could soon make desalination plants an efficient and economic means of sourcing potable water.
The study, released by a group of scientists from MIT’s Department of Materials Science and Engineering (DMSE) in the journal Energy & Environmental Science, claims that the development of more permeable filters using graphene materials will achieve major increases in the energy efficiency of desalination plants, thus promising to make them smaller, faster and more economical.
According to work previously performed by two of the study authors, graduate student David Cohen-Tanugi and professor Jeffrey Grossman, both of whom are with MIT’s Department of Materials Science and Engineering, sheets of perforated graphene harbour immense potential as filtration materials.
Modelling performed by Cohen-Tanugi and Grossman demonstrated that the low thickness of graphene sheets – which are far thinner than the polyamide-based filters which are currently used for desalination purposes, means that water passes through its nanoscale pores with far greater ease.
The strength of graphene also means the filtration sheets are capable of enduring greater pressure and increased flow rates.
According to Cohen-Tanugi, the ability of graphene membranes to permit a greater volume of water to pass through them is the reason why they require less energy, and can increase the efficiency of the desalination process.
This prior research performed by Cohen-Tanugi and Grossman was hailed as groundbreaking within the scientific community and listed as one of the Top 5 Surprising Scientific Milestones of 2012 by the Smithsonian.
The new study shows that by tripling the permeability of their filters, desalination plants could reduce energy consumption by 15 to 46 per cent for the filtration of salt and brackish water, and would require the use of 44 to 63 per cent fewer pressure vessels.
In addition to increased energy efficiency, the concomitant reduction in scale means that desalination plants could take up less area, which could be another major cost saver given the exorbitant price of seaside real estate.