Spatial distributions of granular activated carbon in up-flow anaerobic sludge blanket reactors influence methane production treating low and high solid-content wastewater

The impacts of granular activated carbon (GAC) spatial distributions in up-flow anaerobic sludge blanket (UASB) reactors treating different solid-content wastewater were evaluated in the present study. When treating high solid-content wastewater, the highest methane yield was observed for UASB supplemented with self-floating GAC (74.2 +/- 3.7 %), which was followed by settled + self-floating GAC reactor (65.1 +/- 3.8 %), then settled GAC reactor (58.3 +/- 1.4 %). When treating low solid-content wastewater, all UASBs achieved improved methane yield, and settled + self-floating GAC reactor achieved the highest methane yield (83.4 +/- 3.3 %). Self-floating GAC amended reactor showed the best performance for treating high solid-content wastewater, while settled + self-floating GAC amended reactor was optimal for treating medium and low solid-content wastewater. The spatial distributions of microbial communities differed in the reactors with settled GAC and floating GAC. This study underlines the importance of considering feedwater characteristics when adopting GAC-based UASB processes.

Automated summary

The impacts of granular activated carbon (GAC) spatial distributions in up-flow anaerobic sludge blanket (UASB) reactors treating wastewater with different solid contents were evaluated in this study. The results showed that the addition of self-floating GAC performed the best in treating high solid-content wastewater, while settled + self-floating GAC reactor achieved optimal results for medium and low solid-content wastewater. The spatial distribution of microbial communities varied in reactors with settled GAC and floating GAC.