Performance of a biochar produced from cellulose as admixture in constructed wetlands used to treat wastewater effluent and combined sewer overflows

This study aimed to evaluate the purification capacity of different admixtures in Vertical Flow Constructed Wetlands (VFCWs) when simultaneously applied as a post-treatment to remove micropollutants (MPs) and to depurate untreated wastewater from Combined Sewer Overflows (CSOs). The main novelty lies with the performance intensification of the mixing sand substrate with two alternatives of biologically activated biochar, that can increase the treatment efficiency and also its circularity. Preliminary results demonstrated the feasibility of cellulose recovery and subsequent application of produced biochar for MPs mitigation in the same catchment as the ideal closing loop, where ‘waste’ material is recovered and valorised at once.