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Brazil is the world's leading charcoal producer, mainly used as an energy source and reducing agent for iron ore in the pig iron and steel industry. Despite its vast production, much of the Brazilian charcoal production remains low-tech and inefficient, with limited utilization of by-products. To address potential environmental impacts, promote a circular economy, and reduce energy waste in the charcoal production chain, this study presents the benefits of using wood carbonization by-products through a Life Cycle Assessment (LCA). The analysis was performed by comparing four scenarios: i) Current wood carbonization; ii) Wood carbonization with combustion of non-condensable gases; iii) Wood carbonization with energy recovering of non-condensable gases for electricity generation; and iv) Assessing the utilization of insoluble tar and biomass waste for generating additional electricity, and the use of Pyroligneous Extract (PE) in eucalyptus cultivation. The results demonstrate that by-product utilization prevents energy waste, with an estimated potential to generate 0.19–0.26 MWh per ton of charcoal in Scenarios 3 and 4. Furthermore, 3.3 t of CO2 eq./t of charcoal are sequestered from the atmosphere, and Scenarios 2, 3, and 4 can increase this amount by 5.06%, 6.7%, and 0.48%, respectively. This paper introduces an innovative assessment of PE utilization during eucalyptus cultivation, resulting in a 6.16% reduction in greenhouse gas emission and a 46.98% decrease in abiotic resource consumption, attributed to PE's potential to partially reduce pesticide consumption. [Display omitted] • Photochemical Oxidation is the main impact category due to CO emissions in carbonization kilns. • Potential to generate 0.19–0.26 MWh of electricity per ton of charcoal through by-products utilization. • Forest residues and insoluble tar increase electricity generation potential by 36%. • Charcoal by-products offset GHG emissions from 14 to 203 kg/ton of charcoal. • Pyroligneous Extract use leads to 6% lower GHG emissions and 47% decrease in abiotic resource consumption. [ABSTRACT FROM AUTHOR]

This paper presents an historical approach on the development of the existing biomass carbonization technologies in industrial operation in Brazil, the biggest charcoal producing country in the world. The gravimetric yield of charcoal from wood does not usually surpass 25%; the time of each operation cycle is more than seven days; and less than 50% of the energy contained in the feedstock is transformed into charcoal – the rest is discharged into the environment. The electricity generation associated with charcoal production is nowadays inexistent in Brazil. This paper presents the development of an industrial technology of semi-continuous pyrolysis process, characterized by using metallic kilns with forced exhaust system: the Rima Container Kiln (RCK). The results of the test runs are related to 5 m 3 and 40 m 3 kilns, with a thermal power of 200 kW (pilot scale: 5 m 3 ) and 3000 kW (industrial scale: 40 m 3 ). The low heating value of the pyrolysis gases is 670 and 1470 kJ/m³, respectively. The main results are: a 3 h carbonization time; an average productivity per kiln of 1 ton of charcoal per hour; and a gravimetric yield of 35%. In this paper, four scenarios for the conversion of exhaust gases and tar into electricity were evaluated: the Conventional Rankine Cycle (CRC) and the Organic Rankine Cycle (ORC), each one with and without forest residues utilization. It is shown that the best economic indicators correspond to the scenario where ORC technology is used. The electricity generation cost is around U$30/MWhe for ORC and US$40/MWhe for CRC. [ABSTRACT FROM AUTHOR]

Based on the general acceptance that greenhouse gases from biomass can provide a low carbon energy source, bioenergy pathways are being increasingly included in many countries renewable energy and emission reduction strategies. As a result demand for biomass is rising fast with several regions forecast to encounter major resource stresses over the coming decades. The bioenergy strategies of many countries rely heavily on future imported resource to balance their bioenergy resource demands. Applying a Biomass Resource Model to evaluate and forecast the types and potential availability of different categories of biomass resources from Brazil – a case study of a country with extensive biomass resources and export potential. This research evaluates Brazil's biomass potential to 2030, and analyses the levels of resource that may be available to export. The research finds that Brazil has extensive biomass resources that are potentially sufficient to both balance Brazilian total primary energy demand by 2030 and for Brazil to increasingly become a major exporter of resource for energy end uses. The paper also discusses the potential impact for global biomass trade, if countries such as Brazil were to adopt energy strategies that resulted in greater domestic use of their available biomass. The research's analysis shows that if the Brazilian Government were to adopt strategies to utilise a greater proportion of its resource for domestic energy, Brazil could export up to >25.8% less biomass by 2030 compared to forecast export levels based on Brazil's current policy framework. [ABSTRACT FROM AUTHOR]

Abstract: The paper discusses the availability of biomass in Brazil to supply charcoal to the steel industry on the bases of an initial global assessment of land potentially available for plantations and of Brazilian data that allows refining the assessment and specifying the issue of practical availability. Technical potentials are first assessed through a series of simple rules against direct competition with agriculture, forests and protected areas, and of quantitative criteria, whether geo-climatic (rainfall), demographic (population density) or legal (reserves). Institutional, social and economic factors are then identified and discussed so as to account for the practical availability of Brazilian biomass through six criteria. The ranking of nine Brazilian States according to these criteria brings out the necessary trade-offs in the selection of land for plantations that would efficiently supply charcoal to the steel industry. [Copyright &y& Elsevier]

Abstract: The United States (US) and Brazil have been the two leading producers of fuel ethanol since the 1970s. National policies have supported the production and use of ethanol from corn and sugarcane. US support in particular has included exemption from federal gasoline excise taxes, whole or partial exemption from road use (sales) taxes in nine states, a federal production tax credit, and a federal blender''s credit. In the last decade the subsidization of grain-based ethanol has been increasingly criticized as economically inefficient and of questionable social benefit. In addition, much greater production of ethanol from corn may conflict with food production needs. A promising development is the acceleration of the technical readiness of cellulosic alcohol fuels, which can be produced from the woody parts of trees and plants, perennial grasses, or residues. This technology is now being commercialized and has greater long-term potential than grain ethanol. Cellulosic ethanol is projected to be much more cost-effective, environmentally beneficial, and have a greater energy output to input ratio than grain ethanol. The technology is being developed in North America, Brazil, Japan and Europe. In this paper, we will review the historical evolution of US federal and state energy policy support for and the currently attractive economics of the production and use of ethanol from biomass. The various energy and economic policies will be reviewed and assessed for their potential effects on cellulosic ethanol development relative to gasoline in the US. [Copyright &y& Elsevier]

There is consensus that the use of renewable energy must be expanded. More and more restrictions on the use of fossil derived fuels may open the way for an increased consumption of biomass event those so far not perceived as feasible, such some biomass residue. Energy derived from biomass residues may provide even more benefits because it may replace other sources of higher-grade energy while providing proper destination for residues. Biomass from pruning residue has been overlooked as an energy resource due to many limitations. This paper addresses the issue and the means for energy valuation of pruning residues while provides final destination for them. It presents a framework to overcome most of today's challenges across the world. A case study was carried out to determine the main constraints and how they can influence the decision-making process. The variety of urban pruning residues and their rate of generation, handling, storage, logistics, economic and environmental issues, institutional regulations for a small city in Southern Brazil were taken into consideration in the analysis. Pruning residues were sampled in the field, then handled, shredded, dried, specified, stored and burnt in a concurrent woodburning furnace for testing. The diagnostics of the constraints and the lab tests were summarized and organized in a framework that aimed to assess the energy valuation of pruning residues. Results show that with proper assessment tools, projects, biomass analyses and burning technology energy valuation of pruning residues can be feasible. • Energy valuation of biomass pruning residues is feasible given proper conditions. • A novel assessment framework provides routes to overcome most of today's challenges. • A case study of energy valuation of urban pruning biomass residue in Brazil showed feasible to generate 1 to 1.5 MWe. • Information and data of bulk density, moisture content, heating value, of residues of five urban tree species. • Estimate of opportunity costs of disposal of biomass pruning residues in landfills. [ABSTRACT FROM AUTHOR]