Macroalgae Biorefinery from Kappaphycus alvarezii: Conversion Modeling and Performance Prediction for India and Philippines as Examples

Marine macroalgae are potential sustainable feedstock for biorefinery. However, this use of macroalgae is limited today mostly because macroalgae farming takes place in rural areas in medium- and low-income countries, where technologies to convert this biomass to chemicals and biofuels are not available. The goal of this work is to develop models to enable optimization of material and exergy flows in macroalgal biorefineries. We developed models for the currently widely cultivated red macroalgae Kappaphycus alvarezii being biorefined for the production of bioethanol, carrageenan, fertilizer, and biogas. Using flux balance analysis, we developed a computational model that allows the prediction of various fermentation scenarios and the identification of the most efficient conversion of K. alvarezii to bioethanol. Furthermore, we propose the potential implementation of these models in rural farms that currently cultivate Kappaphycus in Philippines and in India.