Optimization of Screw Mixer to Improve Drying Performance of Livestock Manure Dryer Using CFD Analysis

Abstract

Scarcity of fossil fuels and their emissions of fossil fuel pollutants, such as carbon dioxide, into the atmosphere, and the resulting consequences, have led energy policymakers to look for alternative renewable and clean energy sources. The use of animal wastes is one of the very promising renewable energy alternatives paving the way for a more sustainable energy network. Animal manure produced by livestock farms has a moisture content of about 80%, and such livestock manure is dehydrated to a moisture content of 20–25% and solidified to be used as biomass and fuel for thermal power plants. Previous studies on manure dryers have been concentrated on convection-type dryers, but this type of dryer has the disadvantage of inadequate processing capacity per hour because it cannot agitate manure. In this study, to deal with the drawbacks of conventional livestock manure drying methods, a screw-type dryer was proposed. CFD analysis of the dryer was performed by selecting the viscosity of livestock manure and design parameters of the screw using Ansys Workbench. Through the response surface method, optimal design of the screw shape for the improvement of drying efficiency and smooth discharge of residual manure was carried out.