Evaluation of hydraulic mixing performance in a full-scale anaerobic digester with an external liquid recirculation system using CFD and experimental validation

• CFD anaerobic digesters models were validated by means of complete RTD curve. Design mixing parameters in digestion should be review. Local are strongly recommended for studies. Second-order moments offer geometrical and local information models. The propeller was found crucial to avoid dead volumes formation. Anaerobic (AD) has become an essential process sludge treatment its optimum performance is related degree. In this study, a full-scale Digester (ADer) with external recirculation system studied via single-phase 3D-CFD simulations assess the influence flow 3-blade propeller. model inert tracer tests. design characterise efficiency different scenarios. assessed first, but wide deviations from values found. useful defining degree type mixing, highly studies ADers. A second-order statistical moment proposed as global parameter describe state reliable homogenisation time.