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• A generic optimization model for biorefineries design overarching the entire supply chain, from biomass to market, that allows the modeling of complex biomass systems, such as forests. • A robust formulation that handles uncertainties on both biomass productivity and product selling prices. • An uncertainty model that allows the control of the degree of conservatism regarding negative uncertainties materialization. • A case study for a eucalyptus biorefinery implementation in Brazil producing paper-grade pulp, electricity, and lignin illustrating the capabilities of the proposed model. The dependence of biomass growth on uncontrolled environmental factors and the lack of confidence in product selling price estimation imposes challenges for the efficient design of biorefineries, especially for forest systems, which present complex and long-termed growth behavior. The present work proposes the expansion of an optimization framework for forest biorefineries design to handle uncertainties on both biomass productivity and product selling prices. A robust formulation is proposed under a box and polyhedral uncertainty set formulation allowing its conservatism degree to be controlled. A case study of a eucalyptus biorefinery in Brazil illustrates the model's capabilities. The canonical worst-case approach to uncertainties on selling prices leads to a null optimal Net Present Value (NPV) and, on biomass growth, leads to a design that uses a 70% excess of lands. Scenarios of a controlled degree of conservatism lead to designs closer to the uncertainty-free optimal NPV of 136 bi BRL. [ABSTRACT FROM AUTHOR]

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]

This paper focuses on an analysis of the energy mix profile and energy efficiency of the Brazilian dairy industry. It investigates dairies’ energy mix and energy efficiency and identifies some actions for a cleaner energy mix. Primary data from 37 dairy cheese-making establishments distributed among the Brazilian regions were obtained from online surveys. The results indicate that woodfuel plays a critical role, being the most used fuel in thermal energy generation, while diesel is dominant in electric generation. It also emphasizes that only 51% of the dairy establishments utilize electric energy generators. Other alternative biomass sources are still incipient in the sector, restricted to just 9.5% of the cases for thermal energy generation and no cases for electricity. Regarding the energy efficiency analysis, the results suggest dairies are more scale efficient than pure technical efficient. However, the dairies present a low energy efficiency level. There is no evidence that inefficiencies are differently distributed according to their size. These findings are important for government agencies, industry associations, scientists, universities and research institutes. High inefficiencies, regarding the use of electricity and thermal energy, are a key issue in sustainable bioenergy production. [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]

• The project 'Tropical Biomass & Carbon' and its main product TB&C App is introduced. • TB&C App is an user-friendly tool that estimates C stored in forests of Brazil. • Model performance analysis proved reliability >95% of the TB&C App's models. • Carbon in Amazonian forests can be accurately and precisely estimated. • A dataset containing 64,000 plots with forest variables is delivered as supplement. This article introduces the Tropical Biomass & Carbon Application – the 'TB&C App', a web application available on the permanent link www.tropicalbiomass.com. The TB&C App requires as input attributes 'the smallest and largest diameters', 'number of trees ha−1', basal area ha−1, and 'parameters of the diameter (beta) distribution' describing stand structure. The App delivers outputs at two levels: (1) Stand level, including mean aboveground biomass (AGB) and carbon (AGC), in Mg ha−1, along with confidence intervals (CIs) as measures of uncertainty, and; (2) Tree level estimates, with AGB and diameter for every simulated tree. Phase 1 of the project TB&C comprises four Brazilian forest (and non-forest) formations: Campinarana, Floresta estacional, Floresta ombrofila , and Savana. This article aims to (i) describe the algorithm written for the TB&C App, and (ii) present results of Phase 1. This first phase counts on a standardized database of 1,428 trees with field-measured dry AGB, from plots across the different formations, which is the largest tree-biomass database compiled so far in Brazil. Model uncertainties were incorporated into the modeling process, allowing computation of CIs through an uncertainty approach. The total variance of residuals of AGB was also modeled, aiming at predicting CIs as a function of the quantity of AGB. An analysis of reliability of the equations implemented in the TB&C App indicates that more than 95% (n = 64,000) of the true AGB's fit into the CI outputted by the TB&C App. A comparison with other approaches in the literature shows significant agreement with previous estimates and more conservative estimates where previously-published estimates disagreed with the TB&C App. We cite as advantages of the TB&C App; (i) reliability of the outputs, (ii) a user-friendly layout, (iii) AGB and AGC estimates provided along with robust CIs, and (iv) estimates at the stand and tree levels with consistent totals. A biomass dataset containing information on 64,000 plots is also delivered as supplement of this paper. [ABSTRACT FROM AUTHOR]

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]

Most European countries have committed to ambitious emissions reduction goals. Energy generation in particular is responsible for more than 30% of global emissions, where significant focus has been placed on renewable energy generation, including biomass. On the one hand, there are countries, like the UK, where the biomass stock is insufficient to meet the demand; on the other hand, there are countries, like Brazil, where the stock significantly exceeds the demand. To promote a natural symbiosis, it is necessary to take on the challenge of transporting biomass through long distances in an environmentally and economically efficient manner. This paper aims to assess the efficiency of alternative pathways of international biomass supply-chains. The alternatives involve different biomass origin regions, transportation modes, export ports and processing technologies, including torrefaction. Data Envelopment Analysis (DEA) has been used for the first time to assess the efficiency of the alternative biomass supply chain pathways in a Latin American context, considering multiple-criteria relating to economic and environmental performance simultaneously, such as the biomass delivered cost, the environmental impact and the fossil energy consumption. Additionally, a sensitivity analysis was performed to analyse the robustness of the results under uncertainty in parameter values. The DEA approach presented can assist the process of planning biomass sourcing and improve decision-making under multiple decision criteria. The results can support medium- and long-term strategic decisions for decision- and policy-makers. • Efficiency assessment of biomass supply chain pathways between Brazil and the UK. • 56 alternative pathways considered with different supply chain structure. • Data Envelopment Analysis used for multi-criteria efficiency assessment. • Results can support decision and policy making. • Trade-offs between different criteria identified. [ABSTRACT FROM AUTHOR]