2017 Volume 32 Issue 3 Pages 115-122
The objectives of this study are to clarify the potential use of breathable flexible containers in drying wood chips under varying temperature conditions, to confirm the applicability of the moisture content transition model on those chips, and to determine the properties of parameters in the model. To realize these objectives, transitions of moisture content of wood chips placed inside small-sized breathable containers were measured under the conditions of periodic heating and of an indoor environment at ambient temperatures. The results revealed that periodically heating using waste heat from a chip boiler was effective in reducing the drying time of wood chips. Natural drying using breathable containers at ambient temperatures can be possible, but it typically takes many months. The moisture content transition model that we developed was useful for estimating average moisture content; therefore, the model can be used to predict drying time of wood chips under varying temperature conditions. The coefficient k of the model relates to the average temperature during the measuring periods, while the relationship between k and the distance from breathable surfaces became certain when b was assumed to be a constant.
