Integration of energy-efficient drying in microalgae utilization based on enhanced process integration

We propose an integration of drying with gasification and combined cycle-based power generation for microalgae. This system is based on enhanced process integration, which includes two core technologies: exergy recovery and process integration. Exergy recovery is achieved by exergy elevation and efficient heat coupling, according to each type of heat. Process integration is implemented to minimize the exergy destruction, and hence the remaining energy from one process can be used effectively in other processes. This improves the total energy efficiency. The microalga Chlorella sp. is selected for study because of its high CO2 absorption and high growth rate. The total energy required in the proposed process is calculated based on the target moisture content. It is observed that drying to a lower target moisture content generally consumes less total energy and has a higher coefficient of drying performance than drying to a higher moisture content. A coefficient of drying performance of about 18.5 can be achieved through the proposed process.