Mohanad Abunada earns PhD for research on water desalination

Freshwater is one of the most essential elements for human life. The use of freshwater has been increasing worldwide over the past decades due to continuous population growth, socio-economic development and changing consumption patterns. In parallel, climate change has been also increasing continuously, converting many parts over the world into water-scarce regions. Currently, more than 50% of world’s population experiences severe water scarcity for at least one month per year. This percentage is predicted to rise in the coming years.

Among the different options to mitigate water scarcity, including water conservation, water reuse, rainwater harvesting and others, water desalination has been considered a promising solution especially when it is done using renewable energy. There are several techniques to desalinate water, and my research is focused on reverse osmosis (RO) membrane technology. At present, RO desalination is the dominant technique with around 70% of the total current global desalination capacity.

In RO process, feed water is filtered across RO membranes which remove salts from water and convert it to fresh water. Membrane fouling is one of the main challenges experienced during RO membrane operation. Fouling occurs due to the accumulation of constituents (foulants) in feed water on the membrane, which consequently hinders water transport through the membrane and reduces its permeability. As a result, higher operational energy and more chemical consumption for membrane cleaning will be needed to maintain water production, which leads eventually to an increase in the total production cost and accompanied negative impact on the environment.

To prevent fouling and mitigate its effects, the membrane fouling must be predicted. This enables RO system designers and operators to identify how often they need to clean their RO membranes, how they can optimize the operation conditions of their RO system and how they can improve or upgrade the pre-treatment of the water that goes into the system.

My PhD research focused on one type of membrane fouling, namely ‘particulate fouling’, in which particles deposit onto RO membrane and accumulate on its surface in cake/gel layer hindering water transport through the membrane. My research focused on the development and application of the Modified Fouling Index – Ultrafiltration (MFI-UF) method to more accurately predict particulate fouling in RO systems. I also introduced a complete testing protocol for the MFI-UF method. Engineers, operators and researchers can use this method as a reliable tool to accurately measure and predict the rate of particulate fouling in RO systems, and thus it can support them to design, operate and monitor RO systems effectively and sustainably.

One of the memorable moments was when I started my PhD research since it was nice as many of my friends were also doing their PhD. We were all working and enjoying our times together. The best moment was when I was awarded my doctoral degree!

My PhD research did not go very smoothly: it took longer than I had expected to finish. The Covid-19 pandemic was a very difficult and depressing time as I was working alone in the laboratory and at my office. I also struggled when I received disappointing results from my experiments - this was frustrating at times. Furthermore, I found it challenging to maintain a good balance between my PhD and private life.

For the short term, I am broadening my international experience while I currently work as investment manager at Invest International on various projects on infrastructure in the world. In the future, I would like to work on water desalination in Palestine.

If I could start over, I would manage my expectations and prepare myself mentally that a PhD is not an easy task.