Fig. 4From: Performance optimization of novel multi-unit green wall system for blackwater treatment and reuse on-siteReaction kinetics model fitting. a Freundlich fitting of various pollutants at the start-up stage; b zero-order reactions of NH4+–N and COD; c first-order reactions of NH4+–N and COD; d second-order reactions of NH4+–N and CODBack to article page