Piggery wastewater treatment with algae-bacteria consortia: Pilot-scale validation and techno-economic evaluation at farm level

•Pilot-scale validation of an algae-based piggery wastewater treatment for 208 days.•Techno-economics of algal integration in farm of different sizes (100–10,000 pigs).•Removal of NH4+, PO43− (90%) and COD (59%), with 10.7 g/m2/d biomass productivity.•Organic loading rates and suboptimal climate mainly drive the process performance.•Competitive costs for biomass production (1.9 €/kg) and nitrogen removal (4.3 €/kg).