Clean water through 3D printed membranes

A young start-up at Nanyang Technological University (NTU) has used 3D printing to develop a multifunction water filtration membrane. The new invention claims to be enormously cost saving for wastewater treatment in the paper, food and beverage industry.

The membrane lasts twice as long when compared to conventional membranes, is highly resistant to breakage, and has anti-bacterial and anti-biofouling properties, according to NTU. They also claim it to allow for an unprecedented flow rate of at least ten times faster than current water filtration membranes.

Developed by NTU start-up Nano Sun, at the centre of the multifunction membrane is a patented titanium dioxide nanotechnology. Titanium dioxide nanoparticles are proven to kill bacteria and to break down organic compounds in waste water with the help of sunlight or Ultra Violet rays.

“With more of the world’s population moving into urban cities and generating more wastewater, there is a real need for cost-effective technology. Traditional polymer-based water filtration membranes are faced with issues such as fouling and high breakage, while the developing countries with high industrial output are generating wastewater which is increasingly harder to treat”, says Professor Darren Sun, who invented the technology. “What the world needs is a technology which can turn large volumes of polluted or untreated water into drinking water quickly, safely and at a fraction of the cost.”

With the new Nano Sun’s membranes, biofouling is greatly reduced as organic material and bacteria are killed and destroyed when they come into contact with the membranes. Any organic material that does not decompose can also be quickly burnt by putting the membrane in an oven heated to 700° C, since it is able to withstand high heat unlike traditional polymer membranes.

Apart from the capabilities to improve wastewater treatment and desalination plants, multinational companies in the food and beverage industry have also expressed interest in using their technologies in their production processes, according to NTU. Nano Sun recently signed deals with PT Pelaksana Jaya Mulia, a large Indonesian company, to provide 10.000 m³ of clean water per day. In China, Nano Sun is working with an industrial paper mill in Guangzhou to optimise their wastewater treatment processes, which will lead to savings of 3 million SGD over the next five years.

In the future, the startup is also investing heavily to miniaturize the membranes into more handy products, which can be used for household needs as well as humanitarian aid and disaster relief. In addition, the team is working to scale up its production of membranes from 7 meters to 100 meters per day and explore other product possibilities such as air filtration, disinfection and solar cell industries.