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Ethanol: Main component of a biofuel
A characteristic of sugarcane as a source of biofuels is its ability to generate endless products. In fact, while in Ecuador it is cultivated to produce sugar and ethanol, leading countries in their production, such as Brazil or India, also obtain electricity (with the combustion of the bagasse), vinecase and chemical compounds such as furfural and ammonia.
The great advantage of this technology is that it is based on fermentation, a method known and used in all ethanol plants (even cellulosic), so the appearance of undesirable surprises in the processes is void. This allows the use of any ethanol plant also to obtain biodiesel of ethanol, and elaborate biodiesel. The final effect is the production of both biofurors in a single process, with the consequent economic benefits.
This work is intended to investigate more in depth about the production of biofuel from sugarca abundant and which has not been exploited in its entirety.
Biofuel production from sugarcane in a world perspective
Sugarcane is a semi -stroke with type C4 photosynthetic cycle, belonging to the genus Saccharum, from the family of grasses, composed of species of perennial high grama. The aerial part of the plant is essentially composed of the stems, in which sucrose is concentrated, and by the tips and leaves, which constitute the straw of the sugarcane, as detailed in Figure 8. All these components together total about 35 tons of dry matter per hectare. Caña is one of the most important commercial crops in the world, occupying more than 20 million hectares. Between 2006 and 2007 there were approximately 1.300 million tons. Brazil stands out for having an area planted with almost 7 million hectares, representing 42% of the total world production. It is important to note that the sugar year, adopted worldwide, begins in September and ends in August of the following year.
The ideal climate for cane cultivation is the one that presents two different stations: a hot and humid In the stems. The cane does not present a good productivity in climates such as that of the humid equatorial regions, so the Amazon region does not have extensive commercial crops of that plant.
The complete sugarcane cycle varies according to the local climate, cultural varieties and practices. In Brazil the cycle is generally six years, in which there are five cuts, four crop remains treatments and a reform, as explained below. In general, the first cut 12 or 18 months after work (depending on the cane used), when the so -called plant cane is harvested. The other cuts, when the soca cane resulting from the regrowth is harvested, are carried out once a year, over four consecutive years, with gradual decrease in productivity, until there comes a time that is economically more convenient to replace the cane than make a new cut. At that time the old cane is replaced by a new tillage and thus begins a new productive cycle. During the renewal of the cane the cultivated area remains at rest for a few months and can receive other short cycle crops, such as legumes.
According to the productive cycle of the cane, to stimulate a more or less stable production in the different crops and the rationalization of the use of resources in the agricultural stage (machinery and labor), the production areas must be subdivided into plots in plots in The different stages of the cycle. It corresponds, to a six -year cycle, near one sixth of the total area of each stage. Another important consequence of this productive cycle is that, in the implementation of a cane bioethanol production unit, agricultural activities must begin two or three years before the effective industrial production, to multiply the seedlings and achieve, after starting the grinding, a stable production of raw material for three to four years. To try to reduce costs and preserve soil fertility techniques such as direct crop and the use of controlled traffic structures (etcs) for agricultural operations, which allows to expand the number of cuts, maintaining productivity at high levels .
It is interesting to analyze that, as the typical productive cycle of the cane presents five cuts, over six years, the average productivity per year must take into account the renewal period of the cane. In addition, as a part of the cane produced (about 8%) is intended for the replacement of the cane, the annual productivity, measured in tons of cane effectively processed per planted hectare, is lower than the total productivity evaluated in terms of harvested cane.
On average, the annual productivity, quite influenced by the climatic variability and the producing region, is calculated between 50 t/ha and 100 t/ha (weight of the wet stem), being that the Brazilian average is located around 70 t/ has planted, a value comparable to the best producing regions of other countries. Although there are cane productivity records of up to 200 t/ha, in the Southern Central Region of Brazil – where most of the Brazilian plants are located – those indices are between 78 t/ha and 80 t/ha, while in The state of São Paulo, the main producer, are in the range of 80 t/ha at 85 t/ha. In both cases, the cycle of five cuts is considered.
The possibility of using cane sugars, totally or partially, for bioethanol production becomes a very important characteristic for this agribusiness that, due to the price conditions, existing demand and market prospects, can establish, respecting certain limits, a minimum cost and maximum economic production program. To take advantage of that advantage, several Brazilian plants have sugar and bioethanol manufacturing lines, each with the capacity to process 75% of the juice produced, achieving a margin of 50% of the total process capacity in the face of the extraction capacity of extraction of The grinding.
During this process the water discharge is quite high. Currently, in the conditions of the Brazilian southern center, the capture is around 1.8 m3 per ton of processed cane, but is decreasing significantly, as a result of the implementation of reuse measures, which allow the reduction of the level of capture , as well as the treated water disposal. Considering the entire process of cane bioethanol production, waste consists of vinaza (between 800 and 1.000 liters per ton of processed cane for bioethanol), in the "filter cake" (approximately 40 kg humid per ton of processed cane) and in the ashes of the boilers .
As mentioned earlier, in Brazilian plants this waste is valued and then they become by -products, which are recycled and used as fertilizers. In this way, the need to incorporate mineral fertilizers is significantly reduced and the need for irrigation in the cane are avoids. As the production of bioethanol implies a large removal of water, the demand for energy is high, mainly of thermal energy, prepared according to information from Pizaia (1998).
In relation to the demand for electricity, there is a small variation between the processes, but all these are approaching the value of 12 kWh per ton of processed cane. In the case of bioethanol agribusiness based on sugarcane, all the energy consumed in the process can be provided by a combined system of heat and power production (cogeneration system), installed in the plant, and using only bagazo as a source of energy. Indeed, around the world, many cane sugar plants produce much of the energy they need. In Brazil, plants self-supply and, many times, export to the increasingly important public energy surpluses, thanks to the increase in increasingly efficient equipment.
These last values are related to a sugar production process with two masses (successive crystallization processes), in which honey is not exhausted, but the rest (which contains quite sucrose) is sent to bioethanol production. This allows to improve product quality and reduce energy consumption in sugar production. In short, synergies and the possible complementarity between sugar and bioethanol production help reduce costs and improve the efficiency of agribusiness processes.
Biofuel production in Ecuador
In the present there is only ethanol production in the Ecopaís pilot project, in the city of Guayaquil. This project was launched on January 12, 2011 and its objective is to market a new fuel called Ecopaís, a mixture of 95% extra gasoline and 5% anhydrous ethanol. The plan, which takes place in Guayaquil, is two years old to evaluate the convenience of the introduction of alcohol as a national fuel. The extension of the project to the rest of the country will depend on the results of this project .
The pilot plan is currently producing around 80,000 gallons daily of Ecopaís, for which it demands 4,000 gallons of ethanol (about 15,000 liters) that provides producing, alcohol producer of the state -owned state ingenuity (the trunk). With this production, extra gasoline was replaced by Ecopaís in 19 service stations in Guayaquil. In addition, Production has required using 5,000 liters of ethanol from Loja. Thus, the total supply is 20,000 liters per day . The pilot plan has already demonstrated its viability in terms of market existence and product acceptance, but is limited to replace all extra gasoline in Guayaquil by the Ecopaís mixture (5% ethanol) due to the lack of ethanol production in the country. It should be noted that the distillery was importing molasses from Peru and that 92 degrees raw alcohol matters from Bolivia to cover part of its current production .
Palm, sugar cane and banana are the main second generation residues that the country has according to the Puce Quito researchers who develop pilot biorefinery . It is necessary to evaluate the amount of fuel that can come from this waste, its location and the logistics required for collection and transport to processing plants. The implementation of biorefinerias can generate agricultural productive chains and rural employment around the supply of an existing raw material. The location of several decentralized small -scale refineries can also generate technological transfer alternatives and good quality jobs in small and medium -sized cities in the country.
The availability of oil that, according to current reserves and consumption, allows to anticipate approximately 35 years and the need for ecological fuels, with high octane and degree of oxygenation make it necessary to seriously propose generating generation strategies of energy that allow our country to continue developing and maintaining autonomy and independence with great economic and social implications.
A key strategy for Ecuador is in the maximum use of this raw material since it is an abundant matter in renewable energy, since its commercialization and production has its importance, although to a lesser extent. The data of the Central Bank, informs us, that: the production of the sugarcane contributes 1.4% to the national GDP and generates more than 30.000 direct jobs and 80.000 Indirects especially in the dry season of its harvest (from July to December).
The use of biofuels is that they are a clean and efficient source of energy, so current Home work, such as cooking, heating water or lighting the heating, however, the area that records the most advances in the use of this type of fuels of renewable origin, is the automotive.
Mainly for the economic that results, because of the power capacity that is capable of generating and because it is friendly echo. That is, it emits almost no toxic waste to the environment, significantly reducing the greenhouse effect and environmental pollution. The efficiency of biofuels has been compared to that of fossil fuels derived from oil, discovering that a biofuel drive.