Pathways to economic viability: a pilot scale and techno-economic assessment for algal bioremediation of challenging waste streams

Waste production and landfilling are a growing problem due to population growth and more affluent societies following a ‘take-make-waste’ linear economy. All landfills generate leachate, which must be detoxified before release to the environment. Current leachate treatment technologies are often energy intensive, relatively expensive and ignore the potential resources which are contained within. The use of adapted microbial consortia for bioremediation of leachate offers not only treatment but an opportunity for reutilisation of lost resources, converting them to fuel, feed and chemical products. In this study, pilot scale experimental data for algal–bacterial leachate treatment in a 300 L photobioreactor is used to perform a techno-economic analysis. The analysis considers the process at larger scales and evaluate where optimisation and future research should be focused to reduce costs and make the treatment financially competitive with existing technologies. Reductions in capital expenditure and treatment time are key areas for cost reductions; potentially saving around 90% of the total treatment costs.