Assessment of Sugarcane-Based Ethanol Production

Abstract

This chapter aims to explain how bio-ethanol has been drawn to become a successful alternative to partially replace petroleum as a source of liquid fuels in Brazil. A brief historical analysis about the production of bio-ethanol from sugarcane is presented. The motivation to start the production of the ethanol as biofuel in the 1970s and how the governmental policies have contributed to the ups and downs, successes, and failures of the sugarcane industry is shown. Then, the efficiency of the sector is addressed; firstly, the increasing efficiency of the agricultural sector is discussed, showing how the productivity per hectare has increased in the last decades and which improvements are further expected in a near future. Finally, the industrial process is discussed: the current efficiency in processing sugarcane to produce ethanol and the emerging technologies, not only to process sugarcane juice, but also to harness bagasse, vinasse, and sugarcane straw.fuel, high-energy density, and relatively safe handling) made it an important substitute for liquid fuel from petroleum in the Brazilian energetic matrix. In fact, the world overwhelming dominance of gasoline, diesel, and jet fuel for transportation clearly shows the preference for liquid fuels due to their high-energy density. Except for the ethanol, most of the liquid fuels in the world are petroleum based. As petroleum is not renewable, in the long term, it must be substituted by other kind of energy. Aside from that, the use of fossil energy results in the releasing of greenhouse gas emission, which contributes for global warming. Hence, society in general is looking for alternatives to avoid global warming and thus replace petroleum. Biomass, like the sugarcane, clearly represents a sustainable and low-cost resource that can be converted into liquid fuels on a large scale to have a meaningful impact on petroleum use. Why has bio-ethanol become a successful alternative to partially replace petroleum fuels? A short historyThe beginning of the development of the ethanol fuel in Brazil is related to the petroleum shortage in Brazilian territory and the worldwide oil crisis. Brazil had few oil wells in 1970s, and the country was extremely vulnerable to international oil crisis. In 1973, during the first oil crisis, prices increased by 400%, which greatly affected the Brazilian economy in this way, and the Brazilian government began to seek an alternative to reduce its international dependence on oil. At that time, anhydrous ethanol, produced from sugarcane, had already been mixed to gasoline at a ratio of 5%, since 1931. In 1975, government created the Brazilian ethanol program, Proálcool, which involved many economical sectors to develop bio-ethanol as fuel to replace gasoline [2]. This program had massive governmental funds to develop feedstock and industry. In 1979, during the second oil crisis, Brazil presented the first ethanol fuel-powered car. At that time, Brazil had active state intervention over the price and the production of ethanol [3], which dictate...

Risk-conscious optimization model to support bioenergy investments in the Brazilian sugarcane industry

“…For the production of 1G ethanol to become profitable over sugar a 30% increase in the historical prices of ethanol would be necessary. This seems highly unlikely in the near future, insofar as ethanol needs to remain (at least) 30% cheaper than gasoline for economic competitiveness in Brazil [3]. Finally, our model advises against investment in 2G ethanol technology from surplus bagasse in all of the ethanol price scenario considered.…”

“…As a result of multiple incentive programs the Brazilian government has supported since the 1970s [3], the sugarcane sector currently holds the largest share (17%) among all renewables in the national energy mix [4], while still showing a significant potential for expansion through alternative technological routes. Clearly this sector will continue playing a major role as supplier of biofuel but it might be called upon to play a prominent role as supplier of electrical power too.…”

Dynamics of microbial contaminants is driven by selection during ethanol production

“…Several strategies were used by bioethanol industries for controlling the microbial contaminants such as chemicals, antibiotics, bacteriophage, and enzymes treatments [6][7][8]. Consequently, high costs in cleaning up the equipment arise, reducing the productivity in ethanol production [4,5,9,10]. The main contaminant taxon is a Lactobacillus, specifically a lactic acid bacteria (LAB) found in high proportion during the fermentation procedure [11,12].…”

Produção, purificação e caracterização da enzima lacase do fungo >i<Cochliobolus sativus>/i<

“…A celulose é um material estrutural importante para as plantas composto de muitas unidades repetidas de açúcar, que juntamente com a hemicelulose pode ser decomposta para finalmente ser fermentada em etanol. (Castro et al, 2018).…”

“…Investimentos no desenvolvimento de etanol a partir de material celulósico foram feitos, algumas plantas em escala industrial foram construídas e de fato, até 2018, o processo de etanol celulósico ainda não havia se mostrado completamente e comercialmente viável, mas tem um grande potencial para converter matérias-primas de baixo valor para aumentar a produção de biocombustível. (Castro et al, 2018). Há um grande esforço da comunidade científica para o desenvolvimento de novos processos economicamente viáveis para o aproveitamento da biomassa lignocelulósica, para produção de etanol 2G.…”