Heating Performance of Frozen Lodgepole Pine Lumber

Authors

  • Liping Cai
  • Luiz C. Oliveira

Keywords:

Frozen lumber, heating performance, model prediction, thawing time

Abstract

This study was undertaken to determine the heating process of frozen lodgepole pine (Pinus contorta) lumber because many regions in Canada have to heat-treat or dry frozen lumber in the winter. Because phytosanitary regulations require that lumber products be heat-treated before delivery to customers (core wood temperature of 56°C for 30 min), it is important to determine the time required to reach this criterion. In this study, 10 heating runs were made with different initial moisture contents (MCs) and temperatures using a laboratory kiln humidified with low-pressure steam or cold water spray. To simulate the performance of frozen lumber, the existing heating model for unfrozen lumber was modified by adding a phase-change analysis and was verified using the data from laboratory experiments. The experimental results combined with the model predictions indicated that the thawing time was increased for frozen lumber with higher initialMC. The modified model satisfactorily estimates heating times for frozen lodgepole pine lumber.

References

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Published

2010-10-11

Issue

Number 4 / October 2010

Section

Research Contributions

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