Process and system for the production of ethanol from microalgae

摘要

The present invention provides a process and system for the production of ethanol wherein a microalga capable of accumulating starch in the cells thereof is cultured, the culture solution containing the grown algal cells is concentrated, and ethanol is formed by maintaining the resulting slurry in a dark and anaerobic atmosphere while keeping its pH in the range of 6.0 to 9.0. This process and system can further include additional steps and units for subjecting the residual slurry, from which ethanol has been separated, to methane fermentation, burning it to generate carbon dioxide, and using the carbon dioxide in the microalga culturing step.