Reverse osmosis (RO) treatment systems use membrane technology to provide superior water purification. As the water industry looks to alternative water sources to provide both potable water and water that can be used for industrial and agricultural purposes, RO seems to be an obvious treatment solution, and the market is expected grow at a significant rate over the next several years.
However, the technology can be particularly costly due to the energy required to conduct treatment, as well as the potential costs for disposing the resulting highly corrosive brackish water. In addition, organic materials that are filtered from raw water cause the RO membranes to degrade easily. In order to make RO more easily accessible, researchers are creating membranes that are more efficient and sustainable.
Developments in Membrane Technology for Fouling
There have been many developments in RO membrane technology aimed at improving membrane material and design. In general, the creation of membranes with larger surface areas and thicker spacers helps to reduce fouling by allowing more space between membrane surfaces. Research has also given way to protective films and materials that can be used to create more robust membranes that are able to withstand harsher conditions. For example, a research team in Japan recently developed a carbon nanotube-polyamide nanocomposite membrane that is resistant to chlorine, one of the main causes of membrane fouling.
RO Developments to Improve Energy Efficiency
The second challenge that RO membrane technology advancements are targeting is the high cost that can be associated with running the systems. This issue is being addressed by the research and introduction of thinner, more energy-efficient membranes that require less pressure and energy to filter water. Another method, currently being researched at MIT, is the use of light-based technology to continuously clean RO membranes, which, according to researchers, would help to “reduce operation costs and increase efficiency and water output.”
As the demand for potable water increases and alternative water sources are used to meet some of the world’s potable and agricultural water challenges, advancements to make RO technology more cost efficient and sustainable will help to ensure that RO remains a part of the water treatment conversation for years to come.