A circularity-approach translates into a dynamic, evolving system where the more frequent "waste" is re-integrated into the system, the more valuable it becomes. CO2, calcium, nitrogen & phosphate are good examples.
Furthermore, our algae sector falls within the Blue (Bio)Economy which, by EU definition is an extension of marine resources (pertaining to the cultivation of macro & micro-algae, whether offshore / onshore / inland; - within water bodies, whether fresh / saline or marine).
Their annual report is an informative read, with page 28, (Section 3.2) detailing the importance of algae across the Blue (Bio) Economy.