Influence of selected factors on the energy consumption of frozen logs subjected to thermal treatment in veneer production

This study puts forward an approach for calculating the specific energy consumption and its components required for heating of frozen logs for veneer production, depending on the logs' initial temperature and moisture content. The approach is based on the use of two personal models: unsteady model of the temperature distribution along the radius of frozen logs during their thermal treatment and stationary model of the energy consumption of logs subjected to such treatment as a function of its four multifactorial components. The influence of all combinations between five values of the initial temperature of frozen logs from −1 oC to −40 oC and three values of their moisture content from 0.4 kg·kg−1–0.8 kg·kg−1 on the specific energy required to heat and placticize beech logs with a diameter of 0.4 m at operating temperature of the steaming or boiling medium of 80 oC was investigated. The obtained results show that this energy changes in the range from 46 kWh·m−3 (at −1 oC and 0.4 kg·kg−1) to 114 kWh·m−3 (at −40 oC and 0.8 kg·kg−1) The approach could be applied to calculate the energy and its components required for carrying out of the thermal treatment of various frozen capillary-porous materials.