| Animal waste disposal is of increasing concern due to larger and more concentrated livestock operations with less land available for manure application. Many treatment systems exist which treat the water effectively but are too expensive or labor intensive to be feasible for most farms. Wetlands provide an inexpensive and non-labor intensive means by which to treat wastewater and are favorable to farmers in many ways. A small-scale study investigated the feasibility of treating dairy lagoon effluent using a wetland treatment system with advanced phosphorus removal as a step in the treatment process.; Wastewater effluent from a solid separator and an anaerobic lagoon were applied to a small-scale wetland treatment system consisting of six sets of wetland cells with different retention times (6 and 12 day) and substrates (pea-stone, lava rock, and pea-stone/Septisorb mixture). Concentrations of nutrients were recorded at different stages of the wetland system and evaluated to aid in the development of design parameters for a pilot scale wetland treatment system. Pollutant reductions of 96% for phosphorus, 39% for total inorganic nitrogen, and 75% for COD were accomplished. It was concluded that the pea-stone substrate performed the best in phosphorus and COD reduction while the lava rock substrate performed the best in total inorganic nitrogen reduction. |
