storage and fuel quality of coniferous wood chips

Wood chips from Norway spruce (Picea abies L.) and silver fir (Abies alba L.) were stored for a period of 15 months (experimental pile was 4.0 m high). Atmospheric temperature and the temperature inside the pile at heights of 1, 2, and 3 m were measured in regular intervals. Samples were taken from an assortment of heights at the beginning and the end of the experimental period. Subsequently, the samples were subjected to an analysis of moisture content and other properties such as calorific value (according to the standard STN ISO 1928:2003 and ÖNORM M 7132) and ash content (according to the standard STN ISO 1171). The most significant decrease in the chips’ moisture content, and increase in the calorific value from the beginning of storage, was at the height of 1.0 m. An increase in the moisture content and decrease in calorific value was recorded for samples taken from the height of 3.0 m. Samples taken from this height showed an increase in ash content after a 15-month storage period. The experiment described the influence of specific weather conditions on the development of temperature, calorific value, and ash content of coniferous wood chip piles with particle size up to 35.5 mm.