Cocopeat for wastewater treatment in the developing world. I: Comparison to traditional packing media in lab scale biofiltration columns

Cocopeat, a by-product of coconut processing plants widely available in Vietnam, Thailand, Cambodia, the Philippines, and Indonesia, was studied for its ability to support biological nutrient removal in lab-scale vertical flow columns treating simulated wastewater. Treatment performance for cocopeat was compared to sphagnum peat, a traditional packing medium, and Celite, an inert clay pellet. Removal efficiencies of nitrogen, phosphorus, and biological oxygen demand (BOD) were measured over a period of 325 days. During the treatment period, varying configurations were tested to determine the effect of varying aerobic, anoxic, and anaerobic zones on nutrient removal. Overall, similar BOD removal profiles were obtained for cocopeat and sphagnum peat. Slightly more efficient anoxic conditions and a less acidic environment developed with the cocopeat. Up to 75% nitrogen removal was obtained; however, phosphorus removal was not accomplished using the experimental setup, likely due to the absence of a completely anaerobic treatment zone. Overall, cocopeat appears to be a promising alternative packing material for on-site wastewater treatment in Southeast Asia in terms of nitrogen removal.