Inactivation of Pathogens in Agricultural Wastewater Using Controlled Release Chemical Oxidation Polymer System

Abstract

Animal production in the United States has experienced a large shift from small family farms to large, commercial confined animal feeding operations (AFOs or CAFOs). This trend has resulted in more than 80% of all U.S. livestock revenues being generated by farming practices where swine, cattle, and chicken livestock are confined and fed within enclosed areas more than 45 days per year. The US Environmental Protection Agency (US EPA) reports there are more than 400,000 small to medium sized AFOs and 11,400 concentrated CAFOs raising more than 1000 beef cattle, 2500 swine, 5000 ducks, 10,000 sheep, 55,000 turkeys or 30,000 – 100,000 chickens on a single farm. On a per weight basis, livestock produce 3 to 20 times more biomass and liquid waste than humans; this represents between 1.2 – 1.37 billion tons of wet weight biomass produced by CAFOs each year. As a result of AFO and CAFO practices, the U.S. EPA, U.S. Department of Agriculture, U.S. Geologic Service, and Center for Disease Control suggests the copious amounts of manure and wet biomass produced by CAFOs and poor waste management practices represent the largest threats to surface water and groundwater. This research investigates the use of a controlled release chemical oxidation system designed to deliver chemical oxidants to reduce pathogen concentrations in wastewater from confined animal feeding operations (CAFOs). Potassium peroxymonosulfate was encapsulated within biodegradable polymers to develop a system to control the release of the oxidant for 27 30 days. Low doses of the encapsulated oxidant effectively reduced E. coli, total coliform, and Enterococci in cattle and swine lagoon wastewater between 4 to 7-log10 reduction.. This research suggests use of the controlled release system could prove to be an effective method to reduce pathogen concentrations in wastewater from CAFO and agricultural practices. 1.0 Introduction Animal production in the United States has experienced a large shift from small family farms to large, commercial confined animal feeding operations (AFOs or CAFOs) . This trend has resulted in more than 80% of all U.S. livestock revenues being generated by farming practices where swine, cattle, or chickens are confined and fed within enclosed areas more than 45 days per year. The US Environmental Protection Agency (US EPA) reports there are more than 400,000 small to medium sized AFOs and 11,400 concentrated CAFOs raising more than 1000 beef cattle, 2500 swine, 5000 ducks, 10,000 sheep, 55,000 turkeys or 30,000 – 100,000 chickens on a single farm. As a result of AFO and CAFO practices, the U.S. EPA, U.S. 1562 World Environmental and Water Resources Congress 2011: Bearing Knowledge for Sustainability © ASCE 2011