A New Concept for Removal of Phosphorus from Dairy Farm Waste

The proposed project addresses the problem of over-application of phosphorus to cropland by dairy farms who irrigate their cropland with livestock wastewater. Dairy farmers who have been over-applying phosphorus are facing environmental restrictions to reduce phosphorus. There have been no cost-effective options for those who need to reduce most. Expansion of irrigated acreage will solve the problem but is prohibitively expensive or not feasible in many cases. The project aims to establish the commercial feasibility of a fluidized-bed struvite crystallizer, a new technology that works well in swine wastewater and in a preceding project was successfully adapted to dairy wastewater, meeting its goal of 50% phosphorus reduction. In the proposed project, a crystallizer system will be assembled with full-size components on a dairy farm and different methods of operating will be explored to determine how cost-effectively it can achieve that reduction goal. Results will be rendered into a report useful for communicating with dairy farmers. It is estimated that 2000 dairy farms that are over-applying phosphorus have characteristics that suit them to use of the new technology.