Government policy is driving substitution of petroleum feedstocks by biologically derived feedstocks. However, as biofuels become increasingly pervasive, the debate over the potential of biofuels to become a sustainable source of liquid transportation fuels continues. Much of this debate is accentuated by life-cycle analyses of biofuel production routes, including low yields of biofuels from crops that would otherwise be used for food production, the poor energy balance for producing biofuels and a lack of production and distribution networks. In addition, there is an under-representation of what refiners can bring to the production of biofuels. In fact, true synergies exist between the processing of petroleum and bio-based hydrocarbons which could result in significant cost savings in the production and distribution of biofuels. Further there are intensive efforts underway to develop technologies that can process 2nd generation feedstocks such as agro- and forest- wastes and inedible and algal oils. The long term sustainability of a biofuels industry will be largely driven by the availability of these second-generation feedstocks and the technologies to process them.
1. Why biofuel?
Approximately 50% of the globally produced crude petroleum is refined into transportation fuels, the fastest growing segment of the energy sector. This sharply rising use of a non-renewable feedstock has a significant impact on greenhouse-gas emissions. Biomass is the only renewable energy source that can be converted into liquid transportation fuels. Therefore, increasing biofuel usage in the transportation sector can significantly reduce greenhouse-gas emissions as well as diversify energy sources, enhance energy security, and stimulate the rural agricultural economy.
However, today’s first-generation bio-renewable fuels are derived from oils, grains or sugars. The diversion of these food crops for fuel use results in unsustainable competitive and price pressures on the global food, water, and arable land supply. Therefore, today’s first-generation biofuels should not be perceived as an end solution, but as a necessary but temporary step toward technologies that, in 5-10 years, will permit the use of environmentally-sustainable feedstocks (cellulosic waste, algal oils) with significantly reduced crop-to-wheel CO2 emissions.
2. Current Biofuels Technologies and Feedstocks: A Transitional Step to a Sustainable Future
Current technologies for renewable petrol and renewable diesel rely on vegetable crops, sugars or grains as feedstocks. Today’s best known biofuels are: 1) biodiesel (the fatty acid methyl ester (FAME) produced by reacting methanol with vegetable oils) and 2) ethanol (produced by fermenting the sugars present in sugar cane and corn). However, other biofuels can also be made from vegetable oils or greases through hydroprocessing (the addition of hydrogen) or by processing through an FCC-type process unit. These biofuels are true renewable gasolines and diesels that are physically and chemically indistinguishable from their petroleum fuel counterparts and are thus wholly compatible with the existing automotive fleet and fuel distribution infrastructure. In addition, their fuel quality is comparable or superior to that of petroleum-based diesel and gasoline.
3. The Future of Biofuels: Second Generation and Beyond
Second-generation biofuels will be produced in large measure from a combination of non-food sources such as cellulosic biomass, inedible oils such as Japtropha, camelina, and algal oils. Economically viable technologies for cellulosic conversion are under active development. Algal cultivation/harvesting techniques are being investigated and developed by several organizations. It is important to note that the process technology used today to convert vegetable oils to biodiesel and to green diesel could be utilized directly for the conversion of algal oils. Second-generation technologies could make a significant contribution to future biofuels requirements without competing with food production. Extensive R&D efforts are also being undertaken to develop technologies that convert cellulosic biomass through the pyrolysis oil route to biofuels.
This talk will examine the key drivers for the increased production of biofuels as well as the potential risks. In addition, it will outline the elements which could enable the creation of a sustainable biofuels infrastructure; factors which range from the selection of the feedstock (algae, cellulosic materials), to approaches for improving the energy balance, to new game-changing technologies that create fungible fuels transport and aviation fuels that are fully compatible with existing distribution networks and automotive and jet fleets. UOP’s varied initiatives in this space will be further elaborated upon.
ANL Physics Division Colloquium Schedule