3D finite heat transfer method to optimize a hot air convective system for phytosanitary treatment of wood pallets

Abstract

This work presents the development, experimental validation, and application of a control volume element model of 3D finite heat transfer method to optimize a new convective heat system for phytosanitary treatment of wood pallets. A new treatment system consisting of a heat-recovering design for exhaust gases from a distillery boiler is presented. The 3D spatial domains are discretized with hexahedral blocks to modeling and optimize the operational parameters when block-type pallets are treated. Accordingly, an energy balance is applied and the resulting system of differential equations is discretized in time domain to obtain the spatiotemporal temperature profile in the pallet block as critical geometry. The 3D model is adjusted by correlating simulated with experimental data. Overall heat transfer coefficients are obtained. Temperature and treatment time are optimized. Optimal conditions are found for the studied system with air temperature at 80 degrees C and 137 min treatment time. The thermal efficiency of the new treatment system is found as 9.14% and the index of energy consumption is 0.37 kWh with a cost of 0.53 euro per treated pallet at the studied conditions. The economic feasibility of the new treatment system is discussed.