Comparison of Plastic Trickling Filter Media for the Treatment of Swine Lagoon Effluent

Plastic media trickling biofilter technology is being used on a pilot-scale to treat swine lagoon wastewater for use in a hydroponic greenhouse system. Two treatments of 9 filters each were installed to compare the treatment performance of commercially available BioballsTM and recycled soda six-pack rings and to verify a mathematical description of nitrification in a trickling filter. Determining the effectiveness of trickling filters for nitrification of swine wastewater will allow producers to decide what level of treatment is most economical for their operation. A comparison of trickling filter media will help determine which of the media to be tested will provide the highest level of nitrification for the money. Sampling data under the initial design indicated that no detectable performance difference existed between the two treatments using a combined recycle stream. The system was redesigned to isolate the treatments, which will preserve the difference in performance between the BioballsTM and six-pack rings. Other changes in system operation and in analytical methods will be implemented to ensure consistent and reportable results. Data collection will continue in an effort to correlate actual biofilter performance to model parameters.