At the end of the 19th century and beginning of the 20th century there were considerable advances in the use of alcohol as fuel. At the international level, the German engineer Nikolas Otto used alcohol in one of his motors of the cycle "Otto".
In 1896, Henry Ford designed his first car: a quadricycle powered only with ethanol and in 1908 his automobile model "T" was equipped with an engine that could work with the combination of alcohol and gasoline.
In Brazil, the first "International Exhibition of Alcohol Products and Equipment" and the "Congress of Industrial Applications of Alcohol" took place in 1903 in Rio de Janeiro. At the beginning of the century the first engineering experiments took place in the country and in 1925 the first alcohol-powered car traveled about 430 km from Rio de Janeiro to São Paulo. In the 30’s two important events occurred for the sector. In 1931 it was regulated by law to add 5% of alcohol to gasoline and in 1933 the Sugar and Alcohol Institute (IAA) was created, with the purpose of regulating and controlling production, commercialization and foreign trade of the sector.
During the Second World War, the access to the oil was limited, and the ethanol was then used as an alternative in Brazil, Germany and the United States, as well as in other countries. In this scenario, technologies were developed to supply rockets, considered in the long-distance era. The artifact was the first produced by humans to achieve suborbital space flight. With the end of the war the oil is again accessible, resuming its place of prominence and the use of ethanol is again secondary. In Brazil, government support turns to other sectors, especially after 1953, when Petrobras was founded. Due to the great effort of the private sector, in the 60’s there was a strengthening of the sugar cane sector in Brazil’s Center-South.
In 1973, the first big oil crisis occurred, as an alternative to high prices, were created aspects to reduce this dependency, among them was the National Alcohol Program - Proálcool, created in November 14th, 1975. The military government stimulated the alcohol production deriving from sugarcane or other inputs. This stimulus was based on increasing agricultural productivity, developing distilleries and implementing new production units, also creating an alternative to sugar producers who were experiencing a period of low prices. The Proálcool was divided into five stages:
Early stage – 1975 to 1979
The production occurred in attached plants to sugar plants, in this way infrastructure investments were minimized and also there were the advantage to the approximation with planted areas. The increase in alcohol production during the early stage was over 300%, increasing from 555.6 thousand m³ in the 1975/76 crop to 2,490.6 thousand m³ in the 1978/79 crop. In 1977, the addition of 4.5% of anhydrous alcohol to gasoline began, making it the focus of production. Also during this stage, in July 1979, the first alcohol-powered car, the Fiat 147 model, was launched. The Biofuel was adopted by several automakers and the government reduced taxes on alcohol-fueled cars.
Statement stage – 1978 to 1986
At this stage there was the second oil shock that tripled the price of the barrel, causing the federal government to further encourage alcohol production, reaching 12.3 billion liters in 1986, 15% more than the initial government target. During this stage the mixture of anhydrous alcohol at gasoline was set at 20% and the price of the alcohol liter was consolidated at not more than 65% of the liter price of gasoline. In 1986, among the passenger cars produced in Brazil more than 90% were powered by alcohol.
Stagnation Stage – 1986 to 1995
The drop in the price of an oil barrel, together with an increase in internal production, made the gasoline’s price to fall. The price of hydrated alcohol remained at no more than 65% of the price of the liter of gasoline, lowering the price paid to the producers. The demand for alcohol by the consumer continued to grow, as the price of the product remained attractive related to the price of gasoline and the taxes of vehicles to alcohol remained smaller, but the discouragement to the producers, added to a period of scarcity of public resources Investment, lead to a decline of investments. Therefore even production remained at the level of previous years, higher demand caused a supply crisis in the 1989/90 off-season, causing Proálcool to be discredited. On the other hand, during ECO 92, the reception of more than 100 heads of state was carried out with alcohol-fueled vehicles, in order to demonstrate the importance of biofuel as an alternative to oil.
Redefinition Stage 1995 to 2000
Sugar exports grew to 10 million ton a year, prompting questions about regulating the sector without government presence. As for the alcohol fleet, it represented 0.1% in 1997, generating debates between economic experts and environmental specialists who discussed the determination and stimulation of alcohol use in official vehicles and taxis. In 1998, the mixture of 22 to 24% of anhydrous alcohol as a gasoline additive became mandatory.
Issues related to the protection of natural resources and CO₂ emissions have gained even more space since the 2000s. In the national scenario the great resumption of the use of alcohol as fuel occurred in 2003 when flexfuel vehicles - which run on hydrated alcohol, Gasoline or the mix of these two fuels in any proportion - hit the market. In 2003, 48 thousand light commercial vehicles were sold with the technology, already in 2007 that number reached approximately two million units. According to the National Association of Motor Vehicle Manufacturers (ANFAVEA), in 2008 more than 90% of new cars sold in Brazil had flexfuel technology. In 2004 began the production of the world's first series airplane to fly fueled with 100% hydrated ethanol, Ipanema is certified by the Aerospace Technical Center (CTA) and is an example of biofuel development research.
In 2010, a resolution of the National Agency of Petroleum, Natural Gas and Biofuels (ANP) met the request of plants owners and demanded that gas stations changed the nomenclature of alcohol for ethanol, nomenclature that follows the international standard, favoring biofuel. Still in 2010, deciding to adopt ethanol from sugarcane as the official fuel of its racing, Formula Indy avoided the emission of eight tons of CO2 only in the stage occurred in São Paulo. The Brazilian automobile category Stock Car also began to compete using ethanol, supplied by Cosan Combustíveis e Lubrificantes, as well as in the Dakar Rally and the Sertões Rally, which also adopted biofuel.
Since 2011, due to the high prices of sugar, the volume of alcohol production was reduced, causing the government to change the classification of alcohol from sugarcane that has been classified as fuel, which Allowed the control of the National Agency of Petroleum, Natural Gas and Biofuels (ANP). During this period, researches for the development of biofuels has been encouraged, among them, research that seeks to improve the production of second generation ethanol, which uses bagasse and sugarcane straw to produce ethanol. One of the advantages of second-generation ethanol production is that it can emit 15 times less carbon in the atmosphere than first-generation ethanol, and it is possible to increase production by up to 50% without having to increase the planting area in Brazil. In June Raízen inaugurated the first integrated 2G (2nd generation) ethanol production plant, which received an investment of more than R $ 230 million.
How does work an Ethanol plant?
Anhydrous alcohol is very characterized by the maximum alcoholic content of 99.3 ° (INPM), being composed only by ethanol. It is used as fuel for vehicles (Gasoline C) and raw material to the industry of inks, solvents and varnish.
Second generation Ethanol
It is a hydroalcoholic combination (alcohol and water) with a minimum alcohol content of 92.6 ° (INPM), composed of ethyl alcohol. The use of hydrated alcohol is in the pharmaceutical, alcohol and beverage industries, vehicle fuel and cleaning products. Ethanol is also used as a raw material for the production of vinegar and acetic acid, the synthesis of chloral and iodoform.
The cyclohexane is added and forms a mixture having a boiling point of 63 ° C with the alcohol and water. This mixture has a lower boiling point than alcohol (78 ° C), so water can be removed at the top of the column. By condensation, this mixture will separate into two phases, the lower phase being richer in water, sent to another column where recovery of cyclohexane occurs, which returns to the dehydration process. The anhydrous alcohol, which is obtained with an alcohol content of around 99.3%, is withdrawn at the bottom of the dehydration column, from where it is condensed and sent to storage.
A dehydration column is used, where the MEG is fed to the top of this column and the alcohol to be dehydrated to one third below the top of the column. Different from the cyclohexane process, the MEG absorbs and draws the water to the bottom of the column and the anhydrous alcohol vapors come out from the top, where the alcohol is condensed and sent for storage in the tanks. The MEG concentrates the impurities removed from the alcohol and becomes more corrosive, it is necessary to purify it by passing through a column of ion exchange resins, which retains the salts and reduces the acidity.
The alcohol is vaporized and overheated, and only then sent to the dehydration columns. These columns contain in their interior a material consisting of aluminum hydro silicate containing micropores, called zeolite (popularly known as molecular sieve). This network absorbs the water and lets out the alcohol vapors which are then condensed in the form of anhydrous alcohol. Periodically the regeneration of the zeolite is carried out by the passage under vacuum of alcoholic vapors which are subsequently distilled for recovery of the alcohol contained therein.
Among the advantages of the use of molecular sieve is the fact that there is no addition of chemical input, obtaining a final product with no chemical traces strangers to the alcoholic fermentation and the reduction of cost of production, since the consumption of steam reaches 30 % Lower than in the azeotropic process. The average shelf life of the dehydrating agent is eight years. These characteristics make dehydration through the molecular sieve an environmentally efficient method.
The production of sugar and ethanol generates waste that can be used and processed into by-products. Among the main ones are the filter cake, the vinasse and the bagasse.
Extracted of the milled bagasse and the sludge of decantation, the filter cake is composed of up to 1.8% of phosphorus, considered an essential element for the plants and found in low quantity in the Brazilian soils, besides presenting calcium, magnesium, sulfur and micro nutrients. It has great use as an organic fertilizer, especially for sandy soils.
Rich in potassium and also in calcium, magnesium, sulfur and micro nutrients, the vinasse is formed in the distillation process. It is a fertilizer that serves as an alternative to chemical fertilizers. Among the benefits of vinasse application is the improvement of the physical, chemical and biological properties of the soil.
Certainly the by-product that has received the most attention is sugarcane bagasse. Used as an energy source, it has become an alternative to the possibility of shortages, besides being a raw material for the production of biodegradable plastic. There is also the possibility of producing second generation ethanol using straw and sugarcane bagasse. The main benefits of production are the high availability of this raw material, the possibility of increasing production by up to 50% without increasing the area of cultivation and reducing the emission of carbon in production.
The molasses is a by-product of the manufacture of crystallized sugar, or refining. Without much appreciation until the 50’s, the product was only used in soil compaction, a reality that was changed. Among the applications of molasses is the production of animal feed for Bovine, Equines, Sheep and Goats.
The yeast is used in the fermentation process of the sugarcane juice. During the production of ethanol there is an excess of production of these microorganisms, which have 35% protein and high B vitamins composition, which makes them important as a complement to animal feed. Its production reaches a ratio of 2.5 kilograms to 100 liters of ethanol.
From the ethanol production, the Fusel Oil is a yellowish liquid of variable composition, which is a raw material for refining processing, from which alcohols with varying degrees of purity are extracted and for obtaining other chemical substances, among them varnishes and Solvents. The average ratio of Fusel Oil is approximately 2.5 liters per 1000 liters of alcohol.
The production of ethanol from sugarcane has the advantage of a higher yield per hectare, being produced between six and eight thousand liters per planted hectare, while the beet produces 5.5 thousand liters per hectare and the corn has a productivity of 4,2 thousand liters. The Food and Agriculture Organization of the United Nations states that Brazilian ethanol is more price competitive than any other ethanol produced in other countries. The use of ethanol from sugarcane also has greater benefits in comparison to that of corn and beet in the emission of gases responsible for the greenhouse effect. Sugarcane ethanol reduces on average 89% to the emission of these gases, while the ethanol produced by the beet is reduced by 46% and the production by corn 31% when compared to gasoline. The production of ethanol from sugarcane also generates energy from other sources. The bagasse and sugarcane´s straw produce bioelectricity.