College of Agriculture, Engineering
and Science (CAES)

PhD Study Investigates Invasive Plant’s Potential as a Bioenergy Source

Dr Obianuju Patience Ilo used her PhD in Environmental Science to tackle the problem of the invasive alien water hyacinth plant that clogs Africa’s waterways by exploring how anaerobic digestion and pyrolysis techniques could convert the plant into a source of energy and contribute to research in the water-energy-food nexus.

Ilo is a research officer at the National Biotechnology Development Agency in Abuja, Nigeria. The growing need for researchers to contribute to slowing climate change and improving environmental and health conditions motivated her to pursue her PhD.

She encountered research that revealed the problem posed by water hyacinth (Eichhornia crassipes), a plant native to South America that threatens sustainability at societal, environmental and economical levels. She explained that controlling it is expensive and many developing countries are ill-equipped for the vulnerabilities exacerbated by this plant, but it has potential benefits for a low-carbon, climate-resilient economy.

Her study investigated the conditions, techniques and processes required to optimise the product options from the water hyacinth. Ilo employed pyrolysis and anaerobic digestion techniques as economically feasible methods to produce bioenergy in the form of pyro-oil and biogas from the plant.

She proposes that the plant be used for bioenergy as a feasible measure to mitigate its invasiveness, saying this would also support the emergence of a more climate-resilient nation as utilising pyro-oil and biogas assists in reducing greenhouse gas emissions. Ilo hopes this work will inform policymakers and act as an incentive for investment in biofuel and bioenergy markets.

Ilo’s research was supervised by Dr Sphumelele Lucky Nkomo in the Discipline of Geography and Dr Ntandoyenkosi Malusi Mkhize in the Discipline of Chemical Engineering in the College of Agriculture, Engineering and Science. Her research also resulted in a collaboration with Professor Mulala D Simatele of the School of Geography, Archaeology and Environmental Studies at the University of the Witwatersrand.

Ilo credits the mentorship of Nkomo, Mkhize and Simatele for helping her to navigate the doctoral path with ease, achieve strong results and publish five peer-reviewed papers during the course of her PhD.

She expressed gratitude to her family and National Biotechnology Development Agency colleagues for their unwavering support.

Words: Christine Cuenod

Photograph: Sethu Dlamini