Swansea University in Wales is working on what researchers hope will be a major advance in desalination technology:  A self-cleaning water treatment membrane made of electrically conductive nanofibers.

The researchers want to change the economics of desalination plant operation and maintenance, making it more affordable.  Keeping desalination membranes clean is the great challenge with the technology.  When a membrane becomes fouled with organic and inorganic materials, less water can pass through - efficiency is compromised and capacity is lessened unless greater amounts of energy are used to pushed sea water through.

Water

Conventional methods for cleaning fouled membranes involve chemical treatments.  In countries that are wholly dependent on desalination for potable water, the cost of maintenance is enormous.  The United Arab Emirates (UAE) spends an estimated US$3.5 billion.  Because of its oil income, the UAE can afford it.  Other nations feel a more pressing need for solutions that avoid costly shut-downs and treatments.

Swansea University's Centre for Advanced Technologies and Environmental Research (CWATER) developed a self-cleaning nanofiltration membrane by mixing carbon nanostructures with networked cellulose gel.  The latest advance involves the electrolysis concept at the spacer component of the membrane module where the conductive spacers work as an electrode (cathode) in electrochemical set-up.  The membrane system was subjected to fouling and then exposed to periodic electrolysis, wherein in-situ cleaning of membrane surface by hydrogen bubbles generation at the spacer is applied.  It worked so well, they've applied for a patent.