High nutrient removal rate from swine wastes and protein biomass production by full-scale duckweed ponds

► Swine waste treatment by full-scale duckweed ponds. ► High nitrogen removal rate, one of the highest reported. ► Nitrogen removal ways presented different proportion, depending on nitrogen concentration. ► High protein biomass production (20 times higher than soybean). ► High biomass densities reduce protein production and nutrients recovery rates.