End-of-batch handling in ethanol production: After fermentation is complete, separated yeast biomass can be used for which purposes?

Introduction / Context:
Downstream processing in ethanol plants includes separating yeast solids. This biomass has value beyond disposal, supporting circular and sustainable operations.

Given Data / Assumptions:

• Yeast is non-pathogenic industrial Saccharomyces.
• Biomass is separated via centrifugation or filtration.
• Quality and regulations permit appropriate reuse.

Concept / Approach:
Separated yeast can be reused as pitching yeast (recycle), processed and sold as SCP for animal feed due to high protein content and vitamins, or composted as nutrient-rich organic matter for agriculture.

Step-by-Step Solution:

Verification / Alternative check:
Brewing and bioethanol industries routinely implement these routes depending on economics and regulations.

Why Other Options Are Wrong:

Common Pitfalls:
Skipping quality checks (for example, contamination, heavy metals) before using as feed.

Final Answer:
All of the above.