Time Series Analysis and Control of a Dry Kiln
Keywords:Kiln control, wood drying process, statistical process control
AbstractThis paper presents an application of Engineering Process Control (EPC) techniques, specifically, time series control techniques, to reduce the variability in the drying rate of lumber in commercial dry kilns. The main research objective of this paper is to evaluate the optimality of the drying schedules used in industry by comparing with various feedback control strategies available in the statistical literature. The analysis of the drying process is done by building a single-input-single-output (SISO) Box-Jenkins transfer function model and deriving feedback control strategies based on such a model. The comparisons of the simulations of the drying process, both using kiln schedule-control and the suggested feedback control, show significant reduction in drying rate variability and drying time if the feedback control methods are adopted.
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