Estimating potential harvestable biomass for bioenergy from sustainably managed private native forests in Southeast Queensland, Australia

Background： Australia＇s energy future is at the crossroads and the role of renewable sources is in focus. Biomass from sustainably managed forests provide a significant opportunity for electricity and heat generation and production of liquid fuels. Australia has extensive native forests of which a significant proportion are on private land. However, there is limited knowledge on the potential capacity of this resource to contribute to the expansion of a biomass for bioenergy industry. In addition, there are concerns on how to reconcile biomass harvesting with environmental protection. Methods： We used regional ecosystem vegetation mapping for Queensland to stratify harvestable forests within the 1.8 m hectares of private native forests present in the Southeast Queensland bioregion in 2014. We used a dataset of 52,620 individual tree measurements from 541 forest inventory plots collected over the last 10 years. Tree biomass was estimated using current biomass allometric equations for Australia. Biomass potentially available from selective sawlog harvesting and silvicultural treatment across the bioregion was calculated and mapped. Results： Current sawlog harvesting extracts 41.4% of the standing tree biomass and a biomass for bioenergy harvest would retain on average 36% of felled tree biomass on site for the protection of environmental and fauna habitat values. The estimated area extent of harvestable private native forests in the bioregion in 2013 was 888,000 ha and estimated available biomass for bioenergy in living trees was 13.6 million tonnes （t）. The spotted gum （Corymbio citriodora subsp, variegata） forests were the most extensive, covering an area of 379,823 ha and with a biomass for bioenergy yield of 14.2 t-ha-1 （with approximately 11.2 t.ha-1 of the biomass harvested from silvicultural thinning and 3 t.ha-1 recovered from sawlog harvest residual）. Conclusions： Silvicultural treatment of private native forests in the Southeast Queensland bioregion, has the capacity to supply a large quantity of biomass for bioenergy. The availability of a biomass for bioenergy market, and integration of sawlog harvesting and silvicultural treatment operations, could provide land owners with additional commercial incentive to improve the management of private native forests. This could potentially promote restoration of degraded forests, ecological sustainability and continued provision of wood products.

Review of sustainability, pretreatment, and engineering considerations of asphalt modifiers from the industrial solid wastes

The escalating mass of solid waste at an overwhelming sum requires a global attention to strive for efficient waste management and to outsource the ecological treatments. The asphalt pavement industry that consumes a vast scale of natural resources while contributing to thermal and greenhouse emissions is viewed as a high potential alternative for the application of solid waste as asphalt modifier and substantial waste reduction. In efforts to urge for cleaner and greener asphalt production, a growing trend towards usage of solid waste as a renewable material is paving a sustainable future for the asphalt pavement industry. The economic options of incorporating solid waste into the asphaltic mixture coupled with proven effective performances are a green and cost-effective alternative to mitigate various pavement distresses. Various options either as coarse or fine aggregates and as fillers in powder, ash, or fibre form are to stimulate further research interest to incorporate a diversified range of solid waste into the asphalt binder and asphalt mixture. Prior to incorporating solid waste into the asphaltic mixture through the selected options, prerequisite tests in addressing engineering limitations due to the unknown properties of solid waste are reviewed. The concerns on environmental impact are given heavy metals leaching possibilities into water sources are addressed by Toxicity Characterization Leaching Procedure test, to leverage further the systematic reuse of solid waste in steering towards the cleaner production of the asphalt mixture. The microcosmic traits of solid waste namely surface morphology, mineralogical composition and chemical composition are summarized based on the usage of Scanning Electron Microscope, X-Ray Diffraction, and X-Ray Fluorescence, respectively. This systematic review is an enactment and stimulus for researchers to have a general overview before incorporating solid waste into asphalt mixture.

Power Quality Improvement of Distribution Network Using BESS and Capacitor Bank

The power demand around the world is increasing rapidly.The aging distribution network architectures are used by the existing utility companies to deliver power to the consumers,which significantly affects the reliability,stability and quality of the delivered power.Different techniques such as compensation devices have been used by power system engineers and researchers to maintain the quality of power transmitted to end users.In this paper,wattage and volt-amp reactive(VAR)planning scheme has been proposed by using the combination of battery energy storage systems(BESS)and compensators to deal with the vulnerability of networks to voltage drop and system inefficiency.The cost-effective combination of BESS and shunt capacitor bank will then be analyzed to indicate the benefit of the proposed scheme.