Nanyang Technological University spin-off launches Singapore’s first 3D-printing plant for water filtration membranes
Nanyang Technological University, Singapore (NTU Singapore) recently announced that Nano Sun, a water technology start-up founded by a scientist from NTU, has launched a 3D-printing facility to manufacture a new type of water treatment membrane.
Unlike conventional membrane-manufacturing processes that use acids to make polymers porous that function as filters, Nano Sun 3D-prints millions of nanofibers layered on top of each other, compressed into a thin membrane. This results in a new membrane that has a faster water flow rate than conventional membranes despite having a similar pollutant rejection rate. It allows for the construction of smaller wastewater treatment plants, lowering the costs for land, infrastructure, and labour.
The new membrane is also more resistant to breakage and biofouling, requiring less maintenance and brings about greater cost efficiencies.
The first customers to use this next-gen membrane will be two of the largest semiconductor multinational companies in Singapore and a new municipal wastewater treatment plant in China, which can treat up to 20 million litres of water per day – the equivalent of eight Olympic-sized swimming pools.
Nano Sun’s new 3D-printing manufacturing plant is the culmination of a two-decade effort by its co-founder and NTU Associate Professor, Darren Sun, to develop and deploy his research innovations in the fields of materials science, water chemistry, and advanced manufacturing, supported by the Singapore Economic Development Board.
Nano Sun’s Managing Director and co-founder, Mr Wong Ann Chai, said that finding the right market applications and validating the membranes in a wide range of industrial and municipal wastewater recovery and intensive purification for re-use, is their current focus.
Mr Wong stated, “Now that our technology has been validated, we need to able to provide the most cost-effective solution for our next phase of growth. The international market demand for industrial wastewater treatment is going strong since most countries do not want to pollute their scarce surface water and underground water resources”.
With the three new wastewater treatment contracts, Mr Wong said Nano Sun’s annual revenue is expected to reach S$10 million this year, making it one of NTU’s most successful spin-off companies to date.
Over the next three years, Nano Sun will expand its manpower from a Singaporean team of 18 engineers and staff to about 80, with membrane applications to be deployed in China, Indonesia and Philippines.
Since 2015, the NTU spin-off company has designed, commissioned and delivered over 15 water treatment systems and plants to various governments and companies in Singapore, China, Philippines, and Indonesia.
Growing local enterprise – next-generation manufacturing
NTU Vice-President of Research, Professor Lam Khin Yong said that Nano Sun’s new facility and 3D nano-printed membrane are successful examples of how fundamental research in the laboratories can be transformed into products with real-world impact. He added that Nano Sun’s success demonstrates how disruptive innovations developed in Singapore can help propel the industry forward in the new digital economy. Professor Lam added that the university encourages and supports its faculty in innovation and commercialisation of technologies that they developed.
3d-printed water filtration membranes
At the launch, Nano Sun demonstrated the printing of the industry-standard PVDF (Polyvinylidene fluoride) polymer used in conventional water filtration membranes, which is approved by the United States Food and Drug Administration.
Using a proprietary 3D printer, Nano Sun can print millions of PVDF nano-fibres per second, which is accumulated on a backing material and compressed into an ultra-thin sheet of membrane.
This gives the membrane a much bigger surface area to trap or repel pollutants while allowing water molecules to pass through at a faster flow rate. By adjusting how thick or thin these unwoven fibres are layered on top of each other, the membrane can be made into microfiltration membranes and ultrafiltration membranes.
Further studies are now underway to develop even better anti-fouling additives which can be combined with other materials during the 3D-printing process.