Biofuels Production

Vikash Babu, Ashish Thapliyal, Girijesh Kumar Patel

• Publisher: Wiley-Scrivener
• Year: 2013
• ISBN:
  9781118835739
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Fossil Fuels
• Index: Technology & Engineering

The search for alternative sources of energy to offset diminishing resources of easy and cost-effective fossil fuels has become a global initiative, and fuel generated from biomass is a leading competitor in this arena. Large-scale introduction of biofuels into the energy mix could contribute to environmentally and economicaly sustainable development on a global scale. The processes and methodologies presented in this volume will offer a cutting-edge and comprehensive approach to the production of biofuels, for engineers, researchers, and students.

CHAPTER 1

Introduction to Biofuels

Pramod Kumar¹ and Vikash Babu²,*

¹Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee-247667 (India)

²Department of Biotechnology, Graphic Era University, Dehradun-248002

Biofuels mark their presence since the discovery of fire and have been very profoundly used for ages. The ancient raw material for biofuel is wood, exploited in solid form and having several usages with major applications in cooking and heating. Later on, the evolved form of biofuel came into existence as a form of liquid oil that was used from the time immemorial to light up homes and paths for everyday life. Olive and whale oils are some of the ancient types of biofuels employed for this purpose, mostly derived from plants and animals, they were in use for a very long period of time until the application of kerosene replaced them [1, 2]. Moreover, other forms of biofuel started prevailing from the late eighteen century; ethanol is one of the most exploited biofuels for its remarkable application especially to the transportation sector [3]. Corn derived ethanol was first employed for early transportation, mainly in cars. Subsequently, several other feed stocks were employed as sources for biofuel extraction such as plants like peanuts, hump, grains and potatoes [4]. Biodiesel, a later discovered form of biofuel, came into existence only in the twentieth century [5]. Presently, these two classes are the largest exploited biofuel types.

The twentieth century was an era of exploration and the use of resources with concern to the availability of reserves was not a big question. However, with rising populations and urbanization, finding the energy solution has become an area of prime importance. Major energy thrusts are required from the transportation, industrialization and agricultural sectors. Fossil fuels are key sources to bear the burden of entire need but ever increasing demand and limited stock of such fuels force us to employ alternative approaches for the renewable and sustainable production of energy [6]. Hence, biofuels are considered one of the remarkable solutions for this problem. Fuels that are obtained from biological material and have been recently taken out from their natural growing places or are by-products of living organisms are placed in a class of biofuels contrary to the fossil fuel derived products that are extracted from fossilized organisms buried for millions of years under the earth’s crust and converted to a form of fuel due to high pressure and temperature. Because of renewable nature and the immense possibility of improvement and engineering, biofuels are becoming a promising source of energy contrary to the limited and localized availability of fossil fuels. Moreover, biofuels are a possible solution to the dependence on foreign energy sources and are also suitable to circumvent environmental concerns. There is big hidden potential in biofuel based energy sources, especially when it is combined with efficient agriculture and scientific application that enables it to provide mankind with various raw materials required for food fiber and energy [7].

There are several forms of fuel that can be produced from biomass, referred to in general as biofuel, that cover liquid forms of fuel such as ethanol, methanol or biodiesel and gaseous forms like methane and hydrogen. On the basis of application and feedstock utilization, the biofuel can be summarized in two stages, first generation biofuel and second-generation biofuel [8]. The most predominant types of first generation biofuels are ethanol, fatty acid methyl ester (FAME or biodiesel) and pure plant oil (PPO). The most common form of biofuel exploited worldwide is bio-ethanol with global production increases from 17 thousand million liters in the year 2000 to 68 thousand million liters in 2008 [9, 10]. The key feedstocks for production of ethanol are sugarcane, wheat, sugar beet, rapeseed, soybean and palm oil [11]. Most of ethanol’s worldwide production is contributed by the United States and Brazil by using corn or sugarcane as main feedstock, while Europe produces from potato, wheat or sugar beet. For biodiesel, a major producer is Europe, where Germany is the leader whose production meets 3% of the entire German fuel requirement [12]. Rapeseed is exploited as the most widely used feedstock for an approximate contribution of 70% of European biodiesel production followed by soy that contributes 17% of the production. A smaller portion of production is obtained from sunflower and palm oil [13].

Pure plant oil is a relatively new biofuel resource and it has been gaining importance recently due to early limited local productions. The key features associated with this class are economic value and the feasibility to produce high yield ratios for per hectare production. These properties make it suitable for the markets of developing countries. Some good examples are observed in countries like Malaysia and Indonesia because of the low cost of labor and production in comparison to the countries of Europe and North America. Recently, imports from these countries have gained importance [14]. The main advantages around first generation biofuels are curbing the release of CO₂ and domestic energy security. However, the availability of raw material, adverse effects over the biodiversity and competition for farmlands are major setbacks. Furthermore, the major concerns associated with first generation biofuels are the sustainability of resources from which they are produced as well as their direct competition for food crops and environmental threats related to ecosystems.

There is now well established analysis for biofuels that they should be very efficient in terms of reduction of emissions and net life cycle of green house gas (GHG) emissions that should certainly meet the criteria of social and environmental sustainability. Except for bioethanol from sugarcane, none of the first generation biofuels appear to be fruitful for a future transport fuel mix. All these concerns gave rise to the next stage of biofuel production, so-called second generation biofuels [15]. Due to the choice of feedstock and cultivation technology, second generation biofuels have immense advantages like the consumption of waste and the use of abandoned land, so the second generation of biofuels paves the way for immense application in the biofuel generation that can also satisfy the economical, social and environmental criteria. But unjustified use of second generation biofuel can also compete with regular food crops and may lead to unsustainable resources. Hence, it is of the utmost importance to set some benchmarks for their exploitation like minimum life cycle GHG reductions, land use changes and strict limits for social as well as economic standards.

The criteria to exploit non-food biomass is well addressed by second generation biofuels with the application of several strategies like the application of feedstocks having lignocellulose material that can come from bi-products of agriculture, such as rice husk, corn rub, and sawdust and residues that comes from the forest, such as sugarcane bagasse etc. [16]. According to a report from the US EPA in 2009, cellulosic ethanol is far more promising than any of the first generation biofuels, except bioethanol from the sugarcane of Brazil. Moreover, high organic content of the waste and sludge also possess good potential for application as a feedstock due to the presence of a reasonably high proportion of carbohydrates and proteins. The application of anaerobic digestion to sludge makes it very useful for bioenergy production [17]. The slight modification in the processing of waste can yield other compounds like acetic acid and related organic acids, having additional economic advantages [18]. The acetic acid and organic acid are very important industrial intermediaries that act as carbon sources for the growth of several kinds of microbes that can produce a range of biofuels and chemicals. Apart from these sources, with the recent advancement of microbial engineering, the algal derived feedstock is also showing remarkable potential for the production of biofuel [19]. Because of the versatile nature of algal growth condition, it possesses huge potential to grow over almost any kind of stringent environmental condition like saline water, wastewater, coastal sea water and non-arable lands [20]. Moreover, algal biomass is especially suitable for the high yield of lipids required for production of biodiesel [21]. Because algal feedstock production has very limited competition from regular food crops, it makes it further suitable for biofuel generation.

In sum, a cumulative approach involving specific applications regarding based on the sources of feedstock, availability of land, labor, socioeconomic conditions and selecting a suitable kind of biofuel possesses an immense possibility to meet the needs of fuel in an efficient and sustainable way.

1.1 Global Scenario of Biofuel Production and Economy

The possibility lying in biofuel based energy solutions has gained worldwide attention now that it is visible in the form of policies made by several governments to cut their dependency on fossil fuels by using an environmentally friendly approach. Some of the leading nations in line for promotion of biofuel are the United States, Brazil, E.U. member countries, Canada, China and India. The US government has made one of the most ambitious projections of biofuel by advocating the three-fold increase of bioenergy in the duration of the next ten years [22]. Under the name ‘biofuel’ two major commodities lie, these are bioethanol and biodiesel. The feedstocks for bioethanol production are mainly sugar, corn, soybean, wheat and sunflower whereas jatropha, vegetable oil, palm, rapeseed and soybean are raw materials for biodiesel. Bioethanol is the most forward standing type of biofuel that is ready to replace gasoline and is now part of the many government’s policies for biofuel application, as observed from some of the big countries like Brazil with a mandatory use of 22% bioethanol, 10% in several state of USA and China. Moreover, the hydrous bioethanol (96 percent bioethanol with 4% of water) is also promoted in these countries for extensive use [23]. According to the US Energy Independence and Security Act of 2007, it is envisioned that the renewable energy contribution by bioethanol and other biofuels will increase to 36 billion gallons annually by 2022. Moreover, the US EPA (the United States Environmental Protection Agency) is now permitting the mixing of 10% ethanol due to an amendment of the Clean Air Act. The related effects of these policies are visible in the form of increased corn ethanol production in the US market [24]. The impact of policies made for ethanol production and uses is giving positive outcomes observed for last two decades with respect to the social cost and benefits produced by monitoring biofuel related taxes, tariffs and credit effects of the agricultural sector [25]. This is visible in the form of an average price reduction of 14 ¢ per gallon analyzed from data obtained over the period of 1995–2008 [26]. Such policies demonstrate the linkage of the agricultural and energy markets as is visible in the form of exceeding the mandatory level of ethanol due to high petroleum prices and corn yield [24].

The Agricultural Trade Office of São Paulo projected that total ethanol production for the year 2012 will be 25.5 billion liters. That is followed by total production of 21.1 billion liters in 2011 that is approximately 24.9 percent of the total worldwide biofuel despite the crisis phase that appeared due to many reasons [27, 28]. Brazil is an example of setting a competitive market where successful application of bioethanol is commercialized without subsidy using sugarcane as feedstock [29], moreover Brazil is the largest exporter of bioethanol and the second largest producer after the US

The European Union is the third largest biofuel producer implementing the projection of biofuel by a contribution of five percent share by 2015 and a further rise to ten percent by 2020 [30]. The EU2009 directive has an explicit link to correlate the consumption and production of biofuel to make it a sustainable industry [31]. Moreover, the EU has taken a safe way by prioritizing the import of 30 percent of feedstock or biofuel to reduce the price pressure in EU feedstock. For the anticipated biofuel production in 2012, the E.U. requires 10.3 MMT of sugar beet and 9.7 MMT of vegetable oil and animal fat. For bioethanol, in comparison to the US and Brazil, the E.U. is only a minor producer and for volume contribution bioethanol shares 28 percent of the total biofuel market in the road transport sector [32]. While for biodiesel, the E.U. is the largest producer with 60 percent of the market share [33]. In the European Union, Germany is the largest biofuel producer followed by France as the second largest producer [34]. France also has an ambitious goal to reach a biofuel share of 10 percent by 2015 [35].

For Canada, the mandatory renewable fuel content has been shouted to 5 percent by 2010 as per the recommendations of federal legislation in 2008 [36]. Moreover, the federal mandate also implemented a law requiring two percent renewable content in diesel by 2011. For bioethanol production, Canada has reached almost 2 billion liters of production per year [37], where main feedstock for the bioethanol production in Canada is corn and wheat, the biodiesel is preferably made from canola [38]. Canada has also been subsidized to import biodiesel by a tariff of 6.5 percent as most favored nation and three percent by general preferential tariff [36]. The policies made earlier to make bioethnol an energy alternative are now visible in form of reasonable rise of ethanol production and its sustainability. But due to the limited biofuel production for the short as well as the medium term, it appears that Canada may not become a major player for ethanol production in the near future.

China is also enacting mandates for the blending of ethanol up to 10 ...