Abstract

The design and test performance of a biomass powered natural convection kiln for timber drying is presented. It consists of two sections: the heating section where biomass combustion for inlet air heating occurs and the drying section where the timber is loaded for drying. Inlet air heating is achieved in a heat exchanger of dimension 0.5 m by 0.165 m while temperature stratification in the drying chamber is reduced by letting flue gas from the combustion chamber flow through a space between the side walls of the drying section and the outer housing of the kiln before being expelled. The kiln performance test was carried out for 40 day. Results obtained show that air temperature within the drying section stabilized at 55 -59°C with a minimum relative humidity of 31% (when unloaded) and 45% (when loaded). Timber moisture content reduction from 65 to 30% was achieved in 30 days. Thus it has potential for improved timber drying.

Keywords:

Biomass, drying , kiln , timber,

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Competing interests

The authors have no competing interests.

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