Search

Sugarcane mills currently use sugarcane bagasse to cogenerate heat and electricity, supplying the process with mechanical, thermal and electrical energy. Some of these plants are able to produce surplus electricity to export to the national grid. With the improvement in collection techniques, sugarcane straw has also become available and has been used in some mills as fuel for steam boilers, mixed with sugarcane bagasse. However, due to different traits compared to bagasse, the use of sugarcane straw may pose additional problems of incrustation and corrosion on heat exchange surfaces. Several alternatives and technologies have been studied and tried out in order to increase the production of surplus electricity. Among others, biomass integrated gasifier–gas turbine combined cycle (BIGCC) is a promising technology. However, several attempts have resulted in failure, whether on a pilot or industrial scale. Biomass gasification integrated with internal combustion engines can become an opportunity for generation of small power capacity (<15 MW) and integrated to sugarcane mills. This paper analyzes the difficulties and barriers to increasing electricity generation in the sugarcane industry through studies, projects and experimental and industrial-scale installations that have already been carried out. • Bagasse and cane straw show great potential for electricity generation. • Sugarcane industry in Brazil accounts for 6.4% of the electricity generated. • Biomass integrated gasification and combined cycle can increase electricity generation. • Technological and economic challenges are major barriers to the development of BIGCC. • No BIGCC project already implemented is currently in commercial operation. [ABSTRACT FROM AUTHOR]

In the last decade several scientific papers have dealt with the damages fossil fuels did to our environment. Carbon dioxide has been blamed the chief culprit since it is produced by the automobile fleet that uses diesel or gasoline as a fuel. As a result, several countries are implementing public policies aimed at the replacement of fossil fuels by renewable ones, such as biodiesel. Brazil has become one of them, since the biodiesel production has increased from 736 m 3 to 3,419,838 m 3 in less than ten years. Therefore, this paper intends to briefly review the literature on the history, evolution, and the environmental aspects of biodiesel in Brazil in order to show its positive economic impact on the Brazilian economy, in addition to showing how important this biofuel is to the environment by providing an overview of its advantages when compared to fossil diesel. [ABSTRACT FROM AUTHOR]

Abstract The Energy-Water-Food Nexus is one of the most complex sustainability challenges faced by the world. This is particularly true in Brazil, where insufficiently understood interactions within the Nexus are contributing to large-scale deforestation and land-use change, water and energy scarcity, and increased vulnerability to climate change. The reason is a combination of global environmental change and global economic change, putting unprecedented pressures on the Brazilian environment and ecosystems. In this paper, we identify and discuss the main Nexus challenges faced by Brazil across sectors (e.g. energy, agriculture, water) and scales (e.g. federal, state, municipal). We use four case studies to explore all nodes of the Nexus. For each, we analyse data from economic and biophysical modelling sources in combination with an overview of the legislative and policy landscape, in order to identify governance shortcomings in the context of growing challenges. We analyse the complex interdependence of developments at the global and local (Brazilian) levels, highlighting the impact of global environmental and economic change on Brazil and, conversely, that of developments in Brazil for other countries and the world. We conclude that there is a need to adjust the scientific approach to these challenges as an enabling condition for stronger science-policy bridges for sustainability policy-making. Highlights • Overview of the Energy-Water-Food Nexus in Brazil for science, law and policy. • Review of the complex linkages in the Nexus for water, energy and food security. • Review of the law addressing the Nexus and its coordination deficiencies. • Recommendations for strengthening the Nexus science-policy bridge in Brazil. [ABSTRACT FROM AUTHOR]

Abstract: This paper assesses the learning potential of dedicated wood production systems to boost yields and reduce production costs. In particular, the paper analyses past trends and provides a future outlook of developments in dedicated wood production for three cases: eucalyptus production in Brazil, poplar production in Italy and willow production in Sweden. A main objective of this paper is to evaluate the extent to which experience curves can be devised for conventional woody plantation systems, and whether these can also be applied to short rotation cropping (SRC) production systems. For current average SRC production systems, Italian poplar shows the highest cost at 5.5 €GJ−1 followed by Swedish willow at 4.4 €GJ−1 and Brazilian eucalyptus is produced to the lowest costs at 2.8 €GJ−1. It was assessed to what extent production costs can be reduced per step in the production cycle and how this affects the minimum cost levels that can ultimately be achieved. Ultimate cost reduction could lead to delivered costs of 2.2 €GJ−1 for poplar, 1.9 €GJ−1 for willow and 1.9 €GJ−1 for eucalyptus on better quality lands. Based on historic cost data and production trends, experience curves were applied providing progress ratios for poplar in Italy and eucalyptus in Brazil. Brazilian eucalyptus production follows a steeper slope (63–73%) than poplar in Italy (71–78%). The extent to, and rate at, which cost reductions can occur within the next 20 years were evaluated by combining current costs, minimum cost levels and progress ratios with ranges in European and global biomass demand projections. This shows that, at the assumed growth rates for biomass production in Europe and for global production, minimum cost levels can be reached within the next two decades for all cases. [Copyright &y& Elsevier]

Abstract: While biofuels have currently been regarded as a good alternative for fossil fuels, there remain many debates on their impacts on human and environment. This paper tried to shed light on bio-ethanol in Brazil as one of the main producers and exporters in the world. The main question was to understand “how sustainable is bio-ethanol production in Brazil?” To answer, the political motives of producing bio-ethanol followed by its ecological and socio-economic impacts were discussed. The paper concluded that although bio-ethanol production in Brazil seems environmentally friendly, it might socio-economically be hazardous. [Copyright &y& Elsevier]

Abstract: This paper presents a study based on the Systems Thinking and Scenario Planning (STSP) method, focusing the biodiesel production chain of Rio Grande do Sul State. The aim of the study was to identify key elements to comprehend the systemic structure of interaction among the ties of this chain. The study was held by a team of specialists over five months, including 15 meetings. Discussions were based on quantitative and qualitative data and a systemic map was constructed and refined. Based on this modeling, four different prospective scenarios were comparatively analyzed in order to propose strategic actions to promote the sustainability and competitiveness of the chain. The results were then presented to two different groups of external specialists in order to validate the conclusions drawn and the proposals. Both groups agreed with the ideas presented. The paper is constructed as follows: a brief introduction focusing on contextual elements of the biodiesel production in Brazil and in Rio Grande do Sul; some background material regarding agroindustrial production chains and an overview of the biodiesel production chain of interest; a description of the method used to perform the research; main results and discussion; and conclusions. With this paper the authors also hope to contribute to the discussion regarding competitiveness and sustainability of biofuel chains in Brazil. [Copyright &y& Elsevier]

The biorefinery concept provides a wide perspective of products and uses from the biomass conversion. The drive for cost reductions and the threat of food competition have put residual biomass under the spotlight. Sugarcane is the most produced crop in the world, and its residual bagasse has got the additional feature of abundance. Going beyond its traditional use for electricity and thermal generation, this paper explores the potential alternative uses for the sugarcane bagasse in Brazil. Under an Input-Output perspective, Brazilian production recipes are obtained for six distinct biorefining technologies assuming the use of sugarcane bagasse as feedstock. Also, minimum selling prices are derived for the main products of each technological route assessed, comprising an initial estimative of their cost prices in Brazil. The biomass to ethanol and higher alcohol route presented the higher share (25%) of productive and service sectors into its production recipe. The bioplatform succinic acid route was the only one reaching competitive minimum selling prices (0.57 US$/kg) in comparison to current pricing of the fossil-derived succinic acid. [ABSTRACT FROM AUTHOR]

The replacement of fossil fuels by biofuels has been extremely important worldwide to stimulate the growth of economies based on the sustainability through the use of renewable resources. Anaerobic digestion for biogas production is recognized as a clean technology that allies the suitability of wastes with energy generation, fulfilling the requirements for a sustainable alternative to provide the optimization of the biofuels production. This alternative is especially interesting for the sugarcane ethanol production in Brazil, in which the generation of vinasse, the main liquid waste, is very expressive. Nevertheless, the use of vinasse for anaerobic digestion has been finding some challenges to its establishment in the Brazilian sugarcane biorefineries. This paper reviews the actual context of anaerobic digestion within the sugarcane ethanol production in Brazil, presenting the main obstacles for its full application and the directions to promote it as well. Alternatives for biogas use are also presented and compared, highlighting the environmental and energy advantages of applying anaerobic digestion in the sugarcane biorefineries. This scenario is envisaged as a suitable way to achieve the future biorefineries model, based on the use and recovery of renewable resources with economic, social, and environmental benefits. [ABSTRACT FROM AUTHOR]

Sustainability is a fundamental topic to be addressed in the establishment of a market for jet biofuels in Brazil. The objective of this paper is to enhance the discussion on sustainability of biofuels, and to discuss the main gaps to meet the requirements of sustainability for four groups of feedstock: sugars and starch, oil, lignocelluloses, and wastes. Some general common conclusions can be made for all the analyzed feedstock. In the social sphere, the main positive impacts are the high potential for job creation, income generation and regional development. Regarding the gaps for compliance with sustainability requirements, the following aspects were common to all groups of feedstock: great number of laws and rules; different interpretations and lack of knowledge on how to apply some laws; certain labor laws not adapted to the rural context. The main potential positive impact generated by compliance with requirements is greenhouse gas (GHG) emissions reductions compared to fossil fuels. [ABSTRACT FROM AUTHOR]

Abstract: Bagasse from sugarcane is traditionally used in the Brazilian sugar and ethanol industry to meet the energy needs of its own production processes and, more recently, to generate surplus electricity for sale on the national grid. Currently, the industry faces a difficult choice between either enhancing electricity generation or increasing ethanol production through the biochemical processing of bagasse. The aim of this paper is to examine the most promising technical configurations for bioenergy production using sugarcane bagasse and to discuss which configuration would be the most attractive investment option for the industry. At present, electricity generation through Rankine cycle power plants is the only commercially available alternative. Nevertheless, the analysis cannot be restricted only to the short term. For this purpose, cost analysis for 2030 were developed, and even in scenarios where there is an effective cost reduction of untradeable routes, the alternative of burning bagasse to generate electricity provides the most benefits from an investor perspective. [Copyright &y& Elsevier]

Abstract: The paper evaluates the role of the bio-fuels production in the transportation sector in the world, for programs of greenhouse gases emissions reductions and sustainable environmental performance. Depending on the methodology used to account for the local pollutant emissions and the global greenhouse gases emissions during the production and consumption of both the fossil and bio-fuels, the results can show huge differences. If it is taken into account a life cycle inventory approach to compare the different fuel sources, these results can present controversies. A comparison study involving the American oil diesel and soybean diesel developed by the National Renewable Energy Laboratory presents CO2 emissions for the bio-diesel which are almost 20% of the emissions for the oil diesel: 136g CO2/bhp-h for the bio-diesel from soybean and 633g CO2/bhp-h for the oil diesel [National Renewable Energy Laboratory—NREL/SR-580-24089]. Besides that, important local environmental impacts can also make a big difference. The water consumption in the soybean production is much larger in comparison with the water consumption for the diesel production [National Renewable Energy Laboratory—NREL/SR-580-24089]. Brazil has an important role to play in this scenario because of its large experience in bio-fuels production since the seventies, and the country has conditions to produce bio-fuels for attending great part of the world demand in a sustainable pathway. [Copyright &y& Elsevier]

Abstract: The objective of this paper is to give an overview of the programs, projects and technologies related to the use of biofuels in Brazil. An evaluation of the biomass availability and electricity generation potential for different industrial and agricultural sectors is also presented. As a result an estimation of the overall technical potential for electricity generation based on biofuels in Brazil is presented as well. In addition, the state-of-the-art of different biomass electricity conversing technologies is discussed. A diagram is presented about the organization links and funding of biomass energy research activities in Brazil. Main development and research activities being carried out in this area at the Excellence Group in Thermal Power and Distributed Generation - NEST at the Mechanical Engineering Institute of the Federal University of Itajubá - UNIFEI, located in the city of Itajubá, Brazil are presented. [Copyright &y& Elsevier]