Extraction and handling of dust and chips is an indispensable part of any production line in the wood industry. There are strict national and international regulations and prescriptions concerning air quality in workrooms, safety measures for avoiding fire and dust explosion, which are highly dependent on the efficiency of dust extraction from woodworking machines and dust separation devices, physical-mechanical properties of dust particles, and their behavior in air stream and bulk. This book is an attempt to summarize our present knowledge on this subject, and also several new derivations, experimental results, and new suggestions are introduced.

The main disadvantageous properties of wood dust and chips are their irregular shape, hairy surface with voids, and their more or less plastic behavior during static and impact loading. In bulk, they are inclined to settling due to their own weight (creeping) which makes difficult the outflow through an orifice. In order to overcome these difficulties, it is necessary to know their important physical and mechanical properties and to use them correctly to calculate and optimize technological processes. Some new experimental results and theoretical derivations stimulate us to revise till now used calculation methods such as particle separation in cyclones. Furthermore, a quite new theory and calculation method is elaborated describing friction losses in pneumatic transportation of wood dust and chips. Numerous improvements are included to the topic such as• new measurement results for particle size distribution as a function of wood