In the heart of Thailand, researchers are brewing a potent solution to one of the energy sector’s most pressing challenges: capturing carbon dioxide (CO₂) from biogas-fueled power plants efficiently and sustainably. Led by Weerawat Patthaveekongka from Silpakorn University’s Department of Chemical Engineering, a team has developed an innovative process that integrates amine-based CO₂ capture with bio-methanol synthesis, using waste methanol as a solvent. This breakthrough, published in Results in Engineering (which translates to ‘Results in Engineering’ from Thai), could revolutionize the way we think about carbon capture and utilization, paving the way for a more circular and low-carbon energy future.
At the core of this research lies the use of diethanolamine (DEA) in methanol as a superior solvent for capturing CO₂ from the exhaust gas of biogas-fueled engine-generator systems. The team found that DEA in methanol outperformed traditional aqueous systems, exhibiting higher separation efficiency and lower energy consumption. But here’s where the story gets even more compelling: the researchers discovered that waste methanol, a byproduct of previous methanol distillation, performed almost as well as commercial-grade methanol. This finding opens up exciting possibilities for a more sustainable and cost-effective CO₂ capture process.
“Using waste methanol as a solvent not only reduces the operational cost but also contributes to the circular economy by repurposing industrial waste,” Patthaveekongka explained. This is a significant step forward, as the energy-intensive nature of CO₂ capture has often been a barrier to its widespread adoption.
The process developed by Patthaveekongka and his team involves a pilot-scale absorption-desorption system, where the CO₂-laden gas is first cooled and dehumidified before entering the capture unit. The captured CO₂ is then desorbed at a relatively mild temperature of 80°C, with the team achieving an impressive CO₂ concentration of up to 98% in the desorbed gas. But the real magic happens when they optimized the process, reducing energy consumption to just 11.46 MJ per kilogram of CO₂ captured. This is a game-changer, as energy efficiency is a critical factor in making carbon capture technologies commercially viable.
So, what does this mean for the energy sector? For one, it offers a promising solution for biogas-fueled power plants to reduce their carbon footprint and comply with increasingly stringent emissions regulations. Moreover, by integrating CO₂ capture with bio-methanol production, this process contributes to the development of low-carbon energy systems and supports circular economy initiatives. It’s a win-win situation that could accelerate the transition to a more sustainable energy future.
But the potential doesn’t stop there. This research also opens up new avenues for exploring other waste solvents and optimizing the absorption-desorption process for different types of exhaust gases. As Patthaveekongka puts it, “Our findings provide a strong foundation for further research and development in the field of carbon capture and utilization.”
As the energy sector grapples with the challenges of decarbonization, innovations like this one offer a beacon of hope. By pushing the boundaries of what’s possible, Patthaveekongka and his team are not only contributing to the scientific community but also shaping the future of the energy industry. And as they continue to refine and scale up their process, we can expect to see more of these groundbreaking developments emerging from the labs of Silpakorn University.