Search

The research on Amazon wood waste focuses on the species' individual characteristics, not considering the conditions usually found in the industries, such as variations in the storage method and the waste's condition after exposure to the environment. Accordingly, the objective of this paper was to analyze the management of waste generated by wood industries located in Mato Grosso, Brazil, and to determine the physical and chemical properties of the stocked particulate waste for energy-generation purposes. Twenty-four industries located in eight cities were investigated regarding the generation, management, and trade of wood waste, and samples of the particulate waste were collected for characterization. Each of the evaluated industries processed an average of 857.92 m2 of wood logs per month, and 51.13% of this volume was waste. The species Erisma uncinatum and Qualea spp. stood out due to their greater processing volumes. The types of waste found were of firewood (in 100% of the industries), sawdust (87.5%), wood shavings (16.5%), and wood chips (12.5%). The main destinations of the traded waste were: intermediate buyers (30%), bioenergy plants (22%), cold rooms (18%), and grain dryers (16%). The humidity and bulk density of sawdust and wood chips were, respectively, over 41% and 236 kg m−3. The ash content of 76.7% of the waste was under 2.0%. If the 24 evaluated industries performed the thermochemical conversion of their wood waste, it would be possible to supply electricity to approximately 63 houses with average consumption of 162 kWh/month. The effective management of the waste will result in its commercial appreciation and increase its energy potential. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the properties of wood and charcoal of Eucalyptus sp., from two silvicultural systems (replanting and coppicing), in addition to assessing the economic viability of both systems, through the financial indicators Net Present Value (NPV), Internal Rate of Return (IRR) and Payback. The study was carried out in a charcoal producing company, located in the municipality of Itamarandiba, Minas Gerais, Brazil. The results showed that the wood from the coppice system has a lower Mean Annual Increment and a higher heartwood/sapwood ratio, producing a more friable charcoal and with lower productivity compared to the replanting system. Regarding the economic analysis, both systems were economically viable, with an IRR greater than the discount rate and a positive NPV. Comparatively, the economic results of the coppice system were slightly better, presenting less vulnerability in the sensitivity analysis regarding fluctuations in the price of charcoal. The option for coppice may be interesting for the producer due to its lower financial expenditure and satisfactory economic results, although with lower product quality [ABSTRACT FROM AUTHOR]

Pyrolysis is a promising technology for thermal conversion of lignocellulosic biomasses into a higher added value fuel. The aim of this study was to analyze the potential of four agroforestry biomasses to produce energy as a raw material or as a bio-coal. In this study, slow pyrolysis was conducted in three final temperatures to evaluate the bio-coal production of four agroforestry biomasses widely available in Brazil. The biomasses used were sugarcane bagasse (Saccharum sp.), bamboo (Dendrocalamus giganteus), straw bean (Phaseolus vulgaris) and eucalypts wood chips (Eucalyptus sp.). In the first part was presented the raw biomasses proprieties, such as lignin, carbon, hydrogen and ash contents. In the second part was showed the bio-coal proprieties, such as gravimetric and fixed carbon yields, fixed carbon and ash contents. These bio-coal results were showed as a function of final temperature of pyrolysis. The best energy indicators for bio-coal production, such as fixed carbon yield, high heating value, was observed in the bamboo and eucalypts. The bagasse and straw bean biomasses have high concentrations of ash and low lignin content when compared with the other biomasses assessed and are less suitable to produce bio-coal. [ABSTRACT FROM AUTHOR]

Brazilian productivity of eucalyptus trees is one of the highest in the world, and it has sustainable and viable conditions to supply the demand for woody biomass in a large quantity and diversity. This favorable situation makes Brazil one of the countries with the greatest potential for the production development of torrefied woody biomass on a commercial scale. Torrefaction is a mild pyrolysis applied to increase the energy quality of the feedstock. The aim of this study was to evaluate the Brazilian potential of woody biomass torrefaction for energy purposes. An experimental study was performed evaluating this thermal treatment of eucalyptus wood chips on a semi-continuous screw reactor developed by a Brazilian university. The results showed the increases in the energy quality of eucalyptus wood chips as a function of torrefaction temperature and time. This thermal treatment was technically feasible for the hygroscopicity reduction and the increases of fixed carbon and calorific values of the woody biomass. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the potential use of waste generated by forestry species that occur in semiarid northeastern at Seridó region, Rio Grande do Norte, for the briquettes production, determine the physical and mechanical briquettes properties, and to correlate the wood density with the density after the briquettes production and briquettes density with the compressive strength. Thirty-two trees were collected (eight species with four replications). The wood physical and chemical properties evaluation were held under a completely randomized design. For the variables related to briquette, it was adopted the same design with three replicates for each species, totalizing 24 sampling units. The briquettes produced with jurema-preta wood stood out as a function to higher fixed carbon content, calorific value and higher compressive strength flat. The briquettes made from waste of imburana wood had the worst performances for the studied parameters. It was observed a negative correlation between the wood density and the gain of apparent relative density of the briquettes and a positive correlation between the briquettes density and the compressive strength of flat. [ABSTRACT FROM AUTHOR]

In the context of the circular bioeconomy and cleaner production, the incorporation of the by-products of plant biomass production in the bioenergy chain is fundamental. However, lignocellulosic wastes have properties that hinder their use for the production of biofuels. This study aims to evaluate how blends of lignocellulosic wastes improve the physical, chemical, and mechanical quality of pellets destined to the industrial sector, and to identify the challenges associated with the use of agroforestry biomass as raw material for pelletizing. Pellets were produced from blends of soybean wastes, sorghum wastes, pine needles, rice powder, Eucalyptus sawdust, and charcoal fines. Additionally, pure pellets composed of soybean wastes, sugarcane bagasse, and pine wood were evaluated. The effect of biomass type on the energy density, ash content, net heating value, and ultimate analysis was significant. The pellets produced with soybean wastes presented high contents of N (3.5-4.9%) and ashes (16.4-26.7%), besides low mechanical durability (≤ 96%), hindering its commercialization for industrial purposes. Pellets with sugarcane bagasse presented N (1.5%), S (0.03%), ashes (5.6%), mechanical durability (96.6%), and net heating value (15.1 MJ kg -1 ), suitable for industrial energy use in accordance with ISO 17225-6. The high N and ash contents and the low mechanical durability are the greatest challenges for the energy use of pellets produced from Brazilian agroforestry wastes.