A Third Less CO2
Taking into account the energy saved by using the waste feedstock glycerol and the improved productivity, the new procedure reduces the overall CO2 emissions by 30 per cent compared to fermentation: per kilogram of lactic acid produced, 6 kilograms of CO2 are emitted with the new method compared to 7.5 kilograms with the conventional technology. Also, by lowering the overall cost of the process, the researchers calculated a 17-fold increase of the profit possible by using the new process.
“Our calculations are even rather conservative”, says Morales. “We assumed a glycerol feedstock of relatively good quality. But it also works with low-quality glycerol, which is even cheaper.” Thus, manufacturers could increase their profit even further.
“Although today’s major bioplastic companies are based in the US, the process is relatively simple and could be implemented in other countries that produce biofuel and the by-product glycerol,” concludes Dapsens.
Details of the Study:
Morales M, Dapsens PY, Giovinazzo I, Witte J, Mondelli C, Papadokonstantakis S, Hungerbühler K, Pérez-Ramírez J: Environmental and Economic Assessment of Lactic Acid Production from Glycerol Using Cascade Bio- and Chemocatalysis. Energy & Environmental Science, 5 November 2014, DOI: 10.1039/C4EE03352C
Source: ETH Zürich.