Environmental engineer, Qilin Wang, has pioneered the conversion of waste into carbon-neutral energy, developing technologies to achieve low to zero greenhouse gas emissions in wastewater systems across the globe. Born and raised in China, he received his PhD (Dean’s Award) from The University of Queensland and is currently an Associate Professor (soon to be Professor) at University of Technology Sydney.

Off the back of winning Australia’s Most Innovative Engineer Award (Engineers Australia, 2020), Qilin was awarded winner of the science and medicine category in the 2021 40 Under 40 Most Influential Asian-Australian Awards. As an active driver of Australia’s scientific engagement with Asia, he orchestrates various research collaborations between Asian countries and his team in Sydney, and has been a program and organising committee member of numerous Asian conferences. JP caught up with Qilin to discuss all things environmental and the significant benefits of his research.

 JP On a very elemental level, nitrous oxide (N₂O) is a potent greenhouse gas that can damage the ozone layer. Your research has revealed that the organics in wastewater treatment systems can cause significant N₂O production and you subsequently developed a model to successfully reduce emissions from them. Take us back – what made you initially develop an interest in mitigating N₂O emissions to achieve greenhouse gas-neutral wastewater treatment systems?

Nitrous oxide (N₂O) has a global warming potential of approximately 265 times stronger than carbon dioxide. In general, wastewater treatment accounts for a few percent of global greenhouse gas emissions. In addition, the government also wants to achieve net zero emissions in the future. These collectively stimulated my interest in this niche area. To achieve greenhouse gas neutral wastewater treatment, the development of detailed knowledge and reliable predictive tools for quantifying and mitigating N₂O emission is extremely important. I have contributed to this research and have also developed a model to predict and mitigate N₂O production and emission in wastewater treatment systems.

JP In 2020 you won what can best be described as an equivalent of an Oscar in Australian science – the highly prestigious Australian Eureka Prize for an Outstanding Early Career Researcher. Your research has two key benefits: it substantially reduces greenhouse gas emissions secreted by the plants while the generated energy can be converted to electricity. What else could it be used for?

The generated energy can be converted to electricity and heat. The electricity can be used to power the operation of the sewage treatment plants. It can also be put into the grid and used for cars. The heat can be used to heat the surrounding buildings.

 JP What sort of costs are involved (ballpark) for an average-sized wastewater treatment plant to annually generate its conversion into carbon-neutral energy?

The cost is very low. This technology relies on a waste by-product of wastewater treatment process and therefore no energy-intensive or externally-sourced chemical treatments are required. The implementation of this technology is easy. It only requires the installation of a small, simple mixing tank and minor retro fitting of existing sewage treatment plants with a short payback period.

JP Can you explain how this ‘green’ technology that transforms the sewage treatment plants from large energy consumers into energy generators is actually implemented – essentially the mechanics of the process?

Sewage is an untapped source of energy. Anaerobic digesters are typically used to produce biogas (energy) from the biodegradable organic waste in sewage. However, this results in only 5-10% of energy being available to harvest. This ‘green’ technology unlocks the energy potential of sewage. It can convert the non-biodegradable organic matter in sewage into biodegradable organic matter that would be accessible to biogas-producing microbes to enhance biogas production. The technology can also selectively eliminate the unwanted sewage treatment bacteria that cause unnecessary consumption of biodegradable organics in the sewage treatment process. Thus, more biodegradable organics would be available by microbes for biogas production. These collectively enhance the energy recovery from sewage.

 

JP As the lead inventor for this technology which I believe has an international patent, how actively involved are you in overseeing the marketing and distribution of your technology on a global platform?

The technology is in the process of commercialisation and companies are currently considering licensing it. I often present to industry partners to promote its uptake. I also actively participate in international conferences where I disseminate my work and attract the potential technology investors. In addition to the technology by itself, I also developed an energy, economic and environmental analysis model for technology evaluation. I use this model to show the benefits of this technology to the potential industry partners and investors.

JP Stepping back now, you were born in Qingdao, China to Chinese parents. What sparked your fascination with environmental engineering?

Most Asian countries have made great progress in socio-economic development where more industries and manufacturing plants have been built in the past decades. This rapid development also led to issues relating to the pollution from industrial waste. I constantly noticed them from daily life and also international news. This was the initial trigger for me to start looking into environmental engineering and trying to build a better world. My family was also very supportive allowing me to explore my interests and encouraging me to pursue my studies and career.

 JP You moved to Australia in 2010. Unlike many of the 40 under 40 category winners, you didn’t grow up here. Can you discuss what brought you here?

 I moved to Australia to pursue my PhD at the University of Queensland (UQ). There are world-leading authorities in the field of wastewater and waste treatment at UQ. I followed up with the research development from a world-leading authority at UQ for quite some time before applying for the PhD position. In addition, I am interested in exploring different countries, cultures, and research teams. Now I am at another outstanding university, UTS, to continue research and teach in the field of wastewater and waste treatment.

JP Having lived here now for 11 years and currently holding two esteemed positions: Associate Professor (transitioning to Professor in January, 2022) at the University of Technology Sydney and Australian Research Council (ARC) Future Fellow, is Australia now ‘home’ or do you see yourself more as a ‘global citizen’ given that academia may foster international transfers?

I see myself more as a ‘global citizen.’ I believe that researchers may have a nationality but research does not. In my career, it has been a great pleasure to receive positive feedback from different countries regarding my research outcomes, especially when my work has improved the wastewater or waste treatment in their countries. Of course, as I am in Australia, most of my research focuses on tackling the issues here. I am also glad that my work could help Australian society achieve cheaper, better, more efficient wastewater and waste treatment.

JP From Australia and Europe you have secured 16 grants from Government and Industry with funds amounting to approximately AUD$6 million. How does this compare to environmental engineering research funding in other countries like America, for example?

Australia is very supportive on environmental research and keen on achieving sustainable development and protecting our natural environment. This makes it a fascinating country as it attracts millions of tourists, international students and also researchers.

JP Finally, projecting towards the next ten to twenty years, please explain the key environmental changes that could occur should your technology be applied to wastewater plants globally. And are you dedicated to perfecting your conversion of waste into carbon-neutral energy or are additional research goals quietly percolating away in your mind?

If this technology is applied to the wastewater plants globally, the greenhouse gas emissions are expected to decrease significantly – the equivalent of taking millions of cars off the road. I will continue to work on the conversion of waste to renewable energy. In addition, I made some ground-breaking discoveries while developing this technology that enable the application of this technology in many other fields. I will explore these potential applications in order to solve more real-world problems in the future.