Bioethanol Production In Brazil Research Articles

An energy analysis of first to third-generation bioethanol production in Brazil: the potential for CO<SUB align="right">2 emissions

An energy analysis of first to third-generation bioethanol production in Brazil: the potential for CO<SUB align="right">2 emissions

An energy analysis of first to third-generation bioethanol production in Brazil: the potential for CO<SUB align="right">2 emissions

First (1G), second (2G) and third-generation (3G) ethanol industrialisation produces greenhouse gas (GHG) emissions and increases carbon dioxide (CO2) levels in the atmosphere. In this study, a life cycle assessment (LCA) concluded that hydrolysis and filtration processes have the largest environmental impact, and despite a trend of increased discharge generated by electricity related to 3G introduction, thermodynamic processes still show the highest emissions. These results demonstrate the importance of developing a strong technology base in biofuel industrialisation, predominantly due to the vast potential of 3G production, which increasingly requires higher energy consumption and more efficiency from the industrial system. As such, the aim of this paper is to assess the environmental impact caused by CO2 emissions in 1G, 2G and 3G ethanol production.

Perspectives for the Brazilian bioethanol sector: The innovation driver

This article addresses the future of Brazil's bioethanol sector, focusing on its capabilities to innovate, its efforts toward producing cellulosic ethanol, and on recently implemented policies. Contrary to what has been argued in the literature, Brazil may not be prepared to face the technological and market challenges now emerging in the biofuels domain worldwide. Important productive investments were made by oil, energy, and chemical companies in bioethanol production in Brazil in the first decade of the 2000s; however, that sector has not shown levels of investment in innovation—either for first- or second-generation bioethanol—compatible with the challenges of making bioethanol a global commodity. Even considering recent policies in Brazil toward cellulosic bioethanol, the results achieved have been far from sustainable. This situation is partially due to uncertainties surrounding biofuels worldwide and partially due to contradictory policies toward liquid fuels in Brazil. The Brazilian government has simultaneously promoted both fossil fuels and renewables, thereby creating ambiguity among decision makers. These and other findings were drawn from an in-depth survey on innovation in the bioethanol sector in Brazil conducted in 2014 among 35 productive units affiliated to 58 industrial groups.

Economic-energy-environment analysis of prospective sugarcane bioethanol production in Brazil

Bioethanol from sugarcane can be produced using first-generation (1G) or second-generation (2G) technologies. 2G technologies can increase the capacity of production per sugarcane mass input and are expected to have a key role in future reductions of environmental impacts of sugarcane bioethanol. A hybrid Input-Output (IO) framework is developed for Brazil coupling the System of National Accounts and the National Energy Balance, which is extended to assess Greenhouse Gas (GHG) emissions. Life-cycle based estimates for two sugarcane cultivation systems, two 1G and eight 2G bioethanol production scenarios, are coupled in the IO framework. A multi-objective linear programming (MOLP) model is formulated based on this framework for energy-economic-environmental analysis of the Brazilian economic system and domestic bioethanol supply in prospective scenarios. Twenty-four solutions are computed: four “extreme” solutions resulting from the individual optimization of each objective function (GDP, employment level, total energy consumption and total GHG emissions - 1G scenario), ten compromise solutions minimizing the distance of the feasible region to the ideal solution (1G, 1G-optimized and prospective 1G+2G scenarios), and ten solutions maximizing the total bioethanol production (1G, 1G-optimized and prospective 1G+2G scenarios). Higher diesel oil and lubricants consumption in the mechanical harvesting process has counterbalanced the positive effects of more efficient trucks leading to higher energy consumption and GHG emissions. Lower overall employment level in the 1G+2G scenarios is achieved such that policies linked to reabsorption of sugarcane cutters in alternative activities are positive. Indirect effects from maximizing the bioethanol production increase the total energy consumption and the GHG emissions thus requiring efficiency measures and fossil energy substitution by cleaner sources. The integrated- or country-based analysis of the whole economic system has complemented the process design and process-based analysis, contributing to identify direct and indirect effects that can offset the benefits. Direct and indirect effects on the whole economic system have to be considered in policies and technological choices for prospective bioethanol production, since positive direct effects of 1G+2G plants can be counterbalanced by indirect impacts on other sectors, mainly from chemicals in the process.

Genetic characterization and construction of an auxotrophic strain ofSaccharomyces cerevisiaeJP1, a Brazilian industrial yeast strain for bioethanol production

Used for millennia to produce beverages and food, Saccharomyces cerevisiae also became a workhorse in the production of biofuels, most notably bioethanol. Yeast strains have acquired distinct characteristics that are the result of evolutionary adaptation to the stresses of industrial ethanol production. JP1 is a dominant industrial S. cerevisiae strain isolated from a sugarcane mill and is becoming increasingly popular for bioethanol production in Brazil. In this work, we carried out the genetic characterization of this strain and developed a set of tools to permit its genetic manipulation. Using flow cytometry, mating type, and sporulation analysis, we verified that JP1 is diploid and homothallic. Vectors with dominant selective markers for G418, hygromycin B, zeocin, and ρ-fluoro-DL-phenylalanine were used to successfully transform JP1 cells. Also, an auxotrophic ura3 mutant strain of JP1 was created by gene disruption using integration cassettes with dominant markers flanked by loxP sites. Marker excision was accomplished by the Cre/loxP system. The resulting auxotrophic strain was successfully transformed with an episomal vector that allowed green fluorescent protein expression.

Scientific challenges of bioethanol production in Brazil

Bioethanol (fuel alcohol) has been produced by industrial alcoholic fermentation processes in Brazil since the beginning of the twentieth century. Currently, 432 mills and distilleries crush about 625 million tons of sugarcane per crop, producing about 27 billion liters of ethanol and 38.7 million tons of sugar. The production of bioethanol from sugarcane represents a major large-scale technology capable of producing biofuel efficiently and economically, providing viable substitutes to gasoline. The combination of immobilization of CO₂ by sugarcane crops by photosynthesis into biomass together with alcoholic fermentation of this biomass has allowed production of a clean and high-quality liquid fuel that contains 93% of the original energy found in sugar. Over the last 30 years, several innovations have been introduced to Brazilian alcohol distilleries resulting in the improvement of plant efficiency and economic competitiveness. Currently, the main scientific challenges are to develop new technologies for bioethanol production from first and second generation feedstocks that exhibit positive energy balances and appropriately meet environmental sustainability criteria. This review focuses on these aspects and provides special emphasis on the selection of new yeast strains, genetic breeding, and recombinant DNA technology, as applied to bioethanol production processes.

Sustainability assessment of bio-ethanol production in Brazil considering land use change, GHG emissions and socio-economic aspects

Three sustainability aspects of bioethanol production in Brazil were considered in this paper. Results show that the recent expansion of sugarcane has mostly occurred at the expense of pasturelands and other temporary crops, and that the hypothesis of induced deforestation is not confirmed. Avoided greenhouse gas emissions due to the use of anhydrous ethanol blended with gasoline in Brazil (E25) were estimated as 78%, while this figure would be 70% in case of its use in Europe (E10). Conversely, considering the direct impacts of land use change, the avoided emissions (e.g., ethanol consumed in Europe) would vary from −2.2% (i.e., emissions slightly higher than gasoline) to 164.8% (a remarkable carbon capture effect) depending on the management practices employed previous to land use change and also along sugarcane cropping. In addition, it was shown that where the bulk of sugarcane production takes place, in state of São Paulo, positive socio-economic aspects are observed. The general conclusion is that a significant share of ethanol production in Brazil can be considered sustainable, in particular regarding the three aspects assessed. However, as production conditions are extremely heterogeneous, a generalization of results is not possible.

Optimization of low-cost medium for very high gravity ethanol fermentations by Saccharomyces cerevisiae using statistical experimental designs

Statistical experimental designs were used to develop a medium based on corn steep liquor (CSL) and other low-cost nutrient sources for high-performance very high gravity (VHG) ethanol fermentations by Saccharomyces cerevisiae. The critical nutrients were initially selected according to a Plackett–Burman design and the optimized medium composition (44.3 g/L CSL; 2.3 g/L urea; 3.8 g/L MgSO 4·7H 2O; 0.03 g/L CuSO 4·5H 2O) for maximum ethanol production by the laboratory strain CEN.PK 113-7D was obtained by response surface methodology, based on a three-level four-factor Box-Behnken design. The optimization process resulted in significantly enhanced final ethanol titre, productivity and yeast viability in batch VHG fermentations (up to 330 g/L glucose) with CEN.PK113-7D and with industrial strain PE-2, which is used for bio-ethanol production in Brazil. Strain PE-2 was able to produce 18.6 ± 0.5% (v/v) ethanol with a corresponding productivity of 2.4 ± 0.1 g/L/h. This study provides valuable insights into cost-effective nutritional supplementation of industrial fuel ethanol VHG fermentations.

Social sustainability of the Brazilian bioethanol: Power relations in a centre-periphery perspective

While the environmental and economic dimensions of sustainability have received plenty of attention in biofuel policies and assessment, only recently has the social pillar gained increasing weight, demonstrated e.g. by debates over the dilemmas such as food vs. fuel and large vs. small-scale biofuel production. This paper calls for greater attention to power relations when assessing biofuel policies. A centre-periphery framework is applied for examining power relations in the Brazilian sugar and alcohol sector since the launching of the country's transport biofuel programme, Prolcool, in 1975. Particular attention is paid to the country's poor Northeast, today responsible for a small fraction of bioethanol production in Brazil, but highly dependent on its sugar and alcohol sector for employment and economic output. The analysis demonstrates the pervasive role of unequal and rigid power relations in shaping Prolcool's social impacts. The small sugar elite in the Northeast has increased its power and protected itself against market instability by diversifying its activity, while the benefits have failed to trickle down to the poorest in the sugarcane zone in the Northeast coast. The recent and on-going entry of new players in the Brazilian biofuel scene may provide opportunities of breaking the entrenched power structures and creating space for more pro-poor policies, notably through international sustainability certification. Any such schemes must, however, be designed carefully to avoid capture by the regional elites, and counteract the present tendencies towards further concentration of power a danger particularly acute in the development of advanced next generation biofuels.

Biofuels, solar and wind as renewable energy systems: benefits and risks

Renewable and Solar Energy Technologies: Energy and Environmental Issues.- Can the Earth Deliver the Biomass-For-Fuel We Demand?- A Review of the Economic Rewards and Risks Of Ethanol Production.- Subsidies to Ethanol in the United States.- Peak Oil, EROI, Investments, and the Economy in an Uncertain Future.- Wind Power: Benefits and Limitations.- Renewable Diesel.- Complex Systems Thinking and Renewable Energy Systems.- Sugarcane and Ethanol Production and Carbon Dioxide Balances.- Biomass Fuel Cycle Boundaries and Parameters: Current Practice and Proposed Methodology.- Our Food and Fuel Future.- A Framework For Alternative Energy: Net Energy and Multi-Criteria Analysis.- Bio-Ethanol Production In Brazil.- Ethanol Production: Energy and Economic Issues Related To U.S. and Brazilian Sugarcane.- Ethanol Production Using Corn, Switchgrass and Wood Biodiesel Production Using Soybean.- Developing Energy Crops for Thermal Applications: Optimizing Fuel Quality, Energy Security and GHG Mitigation.- Organic and Sustainable Agriculture and Energy Conservation.- Biofuel Production in Italy and Europe: Benefits and Costs, in the Light of the Present European Union Biofuel Policy.- The Power Density of Ethanol from Brazilian Sugarcane.- A Brief Discussion on Algae for Production: Energy Issues.