What inspires me most is the idea that waste can be transformed — Adejare Adesiyan, engineer and researcher
A Global Journey in Engineering and Sustainability
Adejare Adesiyan’s engineering work and research span three countries — Nigeria, South Africa, and the United States. He is currently a mechanical engineering master’s student at Iowa State University in the US, where he is a teaching assistant and conducting research on process modelling and sustainability assessment for thermochemical conversion systems. In this interview, he speaks about his work and its relevance to industries and society.
Academic Journey Across Three Countries
My academic journey across Nigeria, South Africa, and the United States has been very enriching and transformative. In Nigeria, my BTech in Chemical Engineering gave me a strong engineering foundation and introduced me to process design and problem-solving. In South Africa, my MEng exposed me to deeper research, especially in biogas optimisation, e-waste, and circular economy systems, which really strengthened my passion for sustainability. Now, at Iowa State University in the US, my MSc has expanded my work into biomass pyrolysis, plastic waste valorisation, machine learning, and sustainability assessment.
Altogether, this journey has made me more resilient, adaptable, and globally aware, and has shaped my career towards developing sustainable process systems to solve real environmental and energy challenges.
Transition from Chemical to Mechanical Engineering
For me, the move from chemical engineering to mechanical engineering was really an expansion, not a complete change. Chemical engineering gave me a foundation in process design, reaction systems, and sustainability. However, as I delved deeper into research, I became more interested in the broader energy and thermal systems that underpin those processes. Mechanical engineering gave me the chance to build that broader perspective.
At Iowa State University, I have helped work on biomass pyrolysis, plastic waste valorisation, machine learning, and sustainability assessment. What I want to achieve with this expertise is to combine both fields to design more efficient, practical, and impactful waste-to-energy and sustainable process systems.
Current Research at Iowa State University
At Iowa State University, my current research focuses on process modelling and sustainability assessment for thermochemical conversion systems. I develop process models for biomass pyrolysis using an open-source software called BioSTEAM and Python, simulate the thermal decomposition of plastic feedstocks to predict product yields, and construct detailed mass and energy balances for techno-economic analysis. I also perform sensitivity analysis on indicators such as net present value, minimum selling price, and internal rate of return. In addition, I use life-cycle impact assessment to evaluate environmental performance, and I apply machine learning to develop surrogate models that accelerate simulations and make them more useful for economic and policy decision-making.
The Role of Machine Learning in Energy Systems
Machine learning is very important in fuel and biorefinery systems because these processes are complex and influenced by many variables, such as feedstock composition, reaction conditions, and product distribution. Detailed simulations are useful, but they can be slow when evaluating many scenarios. Machine learning helps by building fast surrogate models that support optimisation, process design, and decision-making. In my work, this is valuable because it allows me to assess fuel production systems more efficiently while also considering techno-economic and environmental performance.
Optimising Biogas Production
Yes. My MEng research focused on the parametric optimisation of biogas production from anaerobic digestion of food waste using Aspen Plus. In that work, I developed a process model and studied how key operating conditions such as organic loading rate, hydraulic retention time, and temperature affect biogas production. The goal was to identify operating windows that improve performance and make waste-to-energy systems more efficient and practical. That project helped me provide professional advice on biogas production biorefinery, build a strong foundation in process simulation, optimisation, and sustainable energy system design. It also led to a publication on the effects of process parameters on biogas production from food waste using Aspen Plus.
Inspiration for Plastic Waste Valorisation
What inspires me most is the idea that waste need not remain waste. I see plastic waste and other underused materials as misplaced resources that can be converted into fuels, chemicals, and other valuable products through better process design and optimisation. That motivation became even stronger when I saw how large the problem really is. UNEP estimates the world generated about 400 million tonnes of plastic waste last year, and around 19 to 23 million tonnes of plastic waste leak into aquatic ecosystems each year. For me, that means plastic waste valorisation is not just an academic topic. It is a real environmental and engineering challenge where research can make a measurable difference.
E-waste management is important because it sits at the intersection of environmental protection, public health, and resource recovery. Electronics contain valuable materials and expensive metals, but they also contain hazardous substances that can contaminate soil, water, and air when they are poorly handled. According to the Global E-waste Monitor 2024, the world generated 62 billion kilograms of e-waste in 2022, but only 22.3 per cent was formally collected and recycled in an environmentally sound manner, and that total is projected to rise to 82 billion kilograms by 2030.
My contributions in this area have focused on the environmental fate of e-waste and on recycling and reuse strategies, because I believe circular approaches are essential to reduce damage while recovering value from discarded products.
Impact of Research on Academia and Society
Presenting my research at international conferences has had a strong impact on my development as a researcher. It has helped me explain my work more clearly, defend my methods under questioning, and receive feedback from people working in related areas such as process systems engineering, sustainability, and waste valorisation. That kind of feedback is valuable because it often exposes blind spots, helps me frame the problem more clearly, and helps me think about the broader relevance of the work. It has also expanded my professional network and connected me with researchers who approach similar problems from different perspectives.
Contributions to Scholarship
I have served as a peer reviewer. Serving as a peer reviewer involves carefully evaluating the quality, originality, and technical soundness of a research manuscript before publication. In that role, I look at whether the research question is important, whether the methods are appropriate, whether the data support the conclusions, and whether the work is clearly written. It also involves giving constructive feedback that helps authors improve their papers. I see peer review as both a responsibility and a learning opportunity, because it sharpens my critical thinking and helps me stay aware of current research standards in the field.
Motivation and Future Goals
What motivates me is the opportunity to solve real problems that affect both industry and society. I am deeply motivated by research with practical value, especially work that can improve environmental outcomes, support sustainable development, and develop useful technologies from overlooked resources. I also enjoy the problem-solving side of research — building models, testing assumptions, analysing data, and gradually turning uncertainty into insight. For me, research is meaningful when it combines scientific rigour with real-world relevance.
My future research goal is to become a leading researcher in process systems engineering for sustainable energy and circular economy applications. I want to keep working at the intersection of process modelling, optimisation, machine learning, techno-economic analysis, and environmental assessment. Over time, I hope to develop robust decision-support tools for plastic waste valorisation, waste-to-energy systems, chemical recycling, and sustainable biorefineries.
My long-term aim is to produce research that not only advances academic knowledge, but also helps industry and governments make better policy decisions about how industrial process systems can be optimised, waste and energy systems are designed and managed.
Impact of Research in the United States
In the United States, I hope my research will help develop more efficient, economically viable pathways for converting waste into useful products at lower selling prices and with lower potential for harmful emissions. I want my work to support technologies and decision tools that help industry and policymakers move toward circular manufacturing, lower-emission energy systems, and better waste management practices. In practical terms, that means designing processes that are not only technically feasible, but also economically competitive and environmentally responsible. I would like my research to help the US better utilise waste streams, such as plastics and biomass, while creating systems that are scalable, resilient, and sustainable.
Leadership and Vision for Nigerian Engineering Education
Leadership means service, responsibility, and helping others move towards a shared goal. I do see myself as a leader because, in both academic and student spaces, I try to guide, support, and contribute in meaningful ways.
Recently in the US, I have served as the president of AFLEC ISU, overseeing activities, facilitating meetings and award-winning events, helping manage organisational risk, and volunteering at City of Ames events like Rummage Rampage. I have also demonstrated leadership as a teaching assistant at Iowa State University, helping students understand difficult concepts and supporting their academic growth.
For me, leadership is not just about position, but about impact, consistency, and service.
As a scholar who has studied engineering in three universities across three countries, I recommend that Nigerian engineering faculties focus on project-based learning, a stronger undergraduate research culture, better training in digital engineering tools, closer industry partnerships, and more international collaboration. Engineering education becomes globally competitive when students are not only taught theory, but are also trained to solve real problems, use modern tools, and work across disciplines.
My own journey has shown me that this combination prepares students to contribute meaningfully to research, industry, and innovation.
