Dry-Matter Loss and Changes in the Chemical Composition of Spruce Wood after Long-Term Storing in the Form of Roundwood

Abstract

Wood stock in a warehouse is a necessary precondition for reliable manufacturing. However, wood can degrade and lose the matter during storage. “Dry-matter loss (DML)” is used to quantify the degradation following the changes in weight of a wood substance. The proposed calculation of DML is based on using parallel figures. The calculated loss of spruce wood substance harvested in winter during a six-month period was 4.5%. The estimated annual loss of wood substance was 5.7%. The loss was caused by a factor with a gradually eliminated effect. The changes in the chemical composition of wood substance were not proportional to the original amount of the isolated chemical substances. Hemicelluloses and lignin suffered from the loss faster than there was a change in the DML of spruce wood. Hemicelluloses were the most unstable isolated compound, with an increased rate of change during the first four months. The number of extractive substances significantly decreased during two months of storage. However, there was an increase in the number of extractive substances after six months of storage. The loss of cellulose was similar to the DML of spruce wood during the whole time of storage. The FTIR analysis confirmed a decrease in the total crystalline index (TCI) and lateral order index (LOI) of cellulose due to the storage of roundwood.

The effect of storage conditions on the characteristics of various types of biomass

“…Dry matter loss was measured to determine the biomass degradation trend during the storage time. The sample was dry by using the oven at 105-degree Celsius and 24 hours before the calculation of dry matter loss (Afzal et al, 2010;Hrčka et al, 2022), as shown in Eq. 1.…”