Fig. 4From: Partial nitritation of stored source-separated urine by granular activated sludge in a sequencing batch reactor a The evolution of mixed liquor suspended solids (MLSS) and sludge volume index (SVI) for the biomass in the sequencing batch reactor. b The particle size distribution of the microbial aggregate sample taken on day 130. The image of granular sludge (inset b)Back to article page