Airflow Resistance of Solid-Separated Dairy Waste for Drying and Storage

Abstract

The resistance of solid-separated solid wastes (SSDWs) to moderate airflow ranging from 0.05 to 0.30 m3/s-m2 was measured at various bed depths and moisture levels. The pressure drop across a loose-fill fixed bed column was observed to increase more rapidly with increasing airflow rates than with increasing bed depths. An increase in the moisture content (10 percentage points) caused a decrease in the pressure drop by an average of 13.2–17.0%, evaluated within a 10–40% moisture content (MC) range. A full-factorial model analysis using standard least squares was used to describe the main effects and interactions of the test parameters in predicting the pressure drop. The Hukill and Ives nonlinear model was able to accurately describe the airflow resistance data of SSDWs at various MCs. Empirical curves describing the SSDW resistance to airflow were developed to aid in the preliminary design of ventilation systems for drying and storage.

Keywords

• airflow resistance
• manure drying
• Hukill and Ives
• dairy bioenergy
• Shedd’s curve