Document Type


Publication Date



Bioresource and Agricultural Engineering | Industrial Technology

Course Number and Title

TSM 416: Technology Capstone


Agricultural and Biosystems Engineering


Agricultural Systems Technology (Blair, Hensel, Kellner, Rietveld)


Michael E. Anderson and Jacek A. Koziel

Problem Statement

Smithfield is the world's leading pork processor and hog producer. They are based out of Virginia and have a large footprint in Iowa with their many pork-producing farms. With all these farms comes a large amount of waste that is used as crop fertilizer. This fertilizer is then stored in a slurry store system or in-ground concrete basin. These externally exposed nutrient storage systems for Smithfield are prone to filling with rain and snow precipitation causing nutrient dilution and, in extreme cases, the potential for overflow. In Iowa, the rate of precipitation per year is greater than the rate of evaporation. This means that an uncovered storage system will call for more time and higher costs for pumping out the diluted nutrient. The solution to this problem is to develop a coverage system to keep out precipitation.

  • Precipitation is causing nutrient storage systems to fill with unwanted water and diluting the nutrients.
  • Diluted nutrient levels increase the need for pumping and decrease the nutrient value of the waste per gallon, which makes the nutrient less profitable.
  • The cover system must have a return on its investment within its lifespan.
  • The cover system must be removable and requires minimal man/equipment power.