Understanding and optimising the performance of algae co-digestion with waste activated sludge

Understanding and optimising the performance of algae co-digestion with waste activated sludge

Unwanted algae growth in water utilities requires frequent scavenging and disposal, which causes operational difficulty and increases operational expenses.

Details

This project proposes to utilise unwanted algae from water utilities as a co-substrate into an anaerobic digester, harvesting energy from unwanted algae to achieve circular economy benefits. The research will aim to understand and optimise the impact of algae addition on anaerobic digestion.

Results from this project will help identify the operating conditions for converting waste algae into energy with additional benefits for anaerobic digestion. 

Research Methodology

Task 1: Understanding the performance of algae co-digestion with waste activated sludge (months 1-24)

This task will understand the performance of algae co-digestion with waste activated sludge. The algae will be collected from the water authority which sponsors this project, along with the waste activated sludge and the anaerobically digested sludge (used as inoculum). Different dosages of algae and waste active sludge will be added to the co-digestion reactors to evaluate the effect of algae to waste active sludge ratio on co-digestion performance. The algae to waste active sludge ratio (mass ratio) will be: 0%, 3%, 5%, 10%, 20%, and 40%. This ratio may be varied with the progress of the project. The samples will be taken both before and after anaerobic digestion. The total solids, volatile solids, chemical oxygen demand, ammonium, volatile fatty acid, alkalinity, dewaterability and biogas production will be measured regularly. The microbial community in the digesters will also be analyzed to provide further insight into the co-digestion performance.

Task 2: Optimising the performance of algae co-digestion with waste activated sludge (months 25-36)

Based on the results of Task 1, the strategy for achieving the optimised performance of algae co-digestion with waste activated sludge will also be proposed.


South East Water is seed funding this project.

WaterRA Contact

Dr Arash Zamyadi
arash.zamyadi@waterra.com.au

Amount being sought

$135,000

Due Date

30th Sep, 2022