Bioenergy Conversion Potential of Decaying Hardwoods

Abstract

Unharvested hardwoods are abundant in eastern Canada, due to the low quality of their fiber and the absence of outlets in conventional wood transformation industries. The objective of this study was to assess the biochemical and thermochemical energy conversion potential of decaying hardwoods and compare their relationships with external and internal indicators of tree degradation. We characterized how wood-decay processes altered the physical and chemical properties of these woods and affected their digestibility yield and their performance according to indexes of stability and efficiency of combustion. DNA analysis on wood samples was also performed to determine the relative abundance of white-rot fungi compared to that of other saprotrophs. All properties stayed within the range of variations allowing the wood to remain suitable for conversion into bioenergy, even with increased decay. We found no significant differences in the physical and chemical properties that are crucial for energy production between wood from externally-assessed live and decayed trees. However, the proportion of wood area affected by rot was significantly associated with increased digestibility yield, and with decreased combustion reactivity. We could not detect any specific effect associated with increased relative abundance of white-rot fungi. These results suggest that the utilization of biomass from decayed hardwoods instead of live trees for bioenergy production should not alter the conversion efficiency and even potentially increase the performance of biochemical pathways, and hence, support their use as feedstock for bioenergy production.

Potential of Forest Biomass Resources for Renewable Energy Production in the Czech Republic

“…The IPCC recognizes that biomass from trees affected by natural disturbances can contribute to the overall technical potential of forest biomass [35]. On the contrary, studies [40,41] assume that in Central Europe, the supply of forest biomass for energy purposes will be endangered due to the bark beetle calamity and the consequent large-scale deforestation.…”

“…Forests are a significant potential source of biomass, and the Intergovernmental Panel on Climate Change (IPCC) has identified forest biomass as an essential source of renewable energy [35]. Forest tree biomass (dendromass) mainly includes forest residues, which the literature [36] divides into primary residues: (by-products of conventional forestry); secondary residues (by-products of industrial processes); tertiary residues (by-products of construction, demolition, and packaging processes).…”

Experimental Analysis of Temperature Influence on Waste Tire Pyrolysis

“…the gross calorific value (GCV) of the tested samples was about 32 MJ/kg, which is significantly more compared to the calorific value of biomass, or to the calorific value of most coals [27][28][29], which, from the energy aspect, makes waste tires a respectable energy source whose possibilities are worth exploring further. The influence of the waste tire granules' size on the yield of solid, liquid, and gaseous pyrolysis products is shown in Figure 2.…”

Using Timber as a Renewable Resource for Energy Production in Sustainable Forest Management

“…They stated that a moderate amount of woody chips and firewood could be harvested without negatively impacting timber production's potential or biological diversity. Dupuis et al [53] analyzed the bioenergy conversion potential of decaying hardwoods and stated that biomass from decayed trees for bioenergy production should not alter the conversion efficiency and, hence, support their use as feedstock for bioenergy production. However, removing decaying trees is not recommended in multifunctional forests as this kind of biomass (deadwood) plays an essential ecological role in forest ecosystems.…”