Separation of Algal Cells from Wastewater Lagoon Effluents. Volume II: Effect of Sand Size on the Performance of Intermittent Sand Filters

摘要

Varying effective sand sizes, hydraulic loading rates, and application rates resulted in profound effects on effluent quality of single stage intermittent sand filtration for secondary wastewater lagoon effluents. The finer effective sand size produced an effluent that satisfied the State of Utah, Class C Regulations except for the requirements for coliform bacteria counts. The lower effective sand size produced greater influent 5-day biochemical oxygen demand and suspended solids removals. Very high coliform removal was exhibited by all prototype intermittent sand filters. The length of consecutive days of operation without plugging by the algae was increased by lowering the hydraulic loading rate.