| Abstract: | Four laboratory reactors (two downflow rock, one downflow wood, and one horizontal flow rock) were operated at 35–38°C for an initial period of six months and later at 23-27°C, with primary clarifier effluent (PCE) from a municipal wastewater treatment plant as the feed to the reactors. A pilot-scale rock medium reactor located at a municipal wastewater treatment plant was operated at 24–28°C initially in the downflow mode and later at 18-20°C in the upflow mode with PCE as feed. The laboratory study showed that PCE can be successfully treated using both downflow and horizontal flow anaerobic filters, with similar performance under both flow modes. Bench-scale filters obtained better BOD and SS removals compared to the pilot-scale filter. |
