Members of the Bioenergy and Bioproducts Center committee have identified several universal gaps that are barriers to the development of alternative fuels/energy in general (not specific to Auburn University). We also identified the capability that Auburn University possesses to address each of these gaps. The following are focus areas and program objectives that the Center will address.
Biomass and coal feedstocks can be thermochemically converted into fuels (e.g. diesel, hydrogen) and chemicals (e.g. ethanol, sugars), processed into highly valuable chemical intermediates, or simply combusted for power production. A central enabling technology in this initiative involves gasification of carbonaceous feedstocks to syngas, a gaseous mixture of carbon monoxide and hydrogen. Syngas is the common starting point for a plethora of established catalytic chemical production schemes including hydrogen, methanol, Fischer-Tropsch liquids (gasoline, diesel, heavy waxes), DME (dimethylether), ammonia and other high value chemical intermediates such as a-olefins. These technologies have proven technical and economical viability. Therefore our initiative will investigate the technical feasibility of producing fuels and chemicals from biomass derived synthesis gas along with direct conversion strategies including power production. Additionally, we are developing new processes and catalysts for the purification of syngas and gas-to-liquid technologies. Our effort also includes converting urban/sub urban wastes and plastics as part of circular economy.
Biological processes provide additional reaction pathways towards the production of fuels and chemicals. The biological processes to be examined include the enzymatic and/or microbial conversion of biomass feedstocks into value-added products and chemical intermediates such as methane, alcohols (methanol, ethanol, butanol, and higher alcohols), carboxylic acids (polylactic acid), and esters (biodiesel). Biological processes have the inherent benefit of being highly selective and customizable; however, these processes often suffer from long processing times and low production rate. Therefore, biological conversion techniques are combined with established high-throughput chemical processing to significantly enhance the technical feasibility of large scale production.
Biomass production systems will be developed to ensure long-term sustainability for Alabama natural resources and profitable conditions for Alabama farmers and forest landowners. Current systems are not necessarily optimized for the production of biomass. Rather, many are targeted at only producing a grain crop or pulpwood or solid wood product. Therefore, research is needed to ensure that production methods are available to produce biomass at the least cost. This includes research on plant genomics, plant establishment and cultivation techniques, optimal fertilization strategies, etc. These production systems also will be devised to produce biomass at a least cost per unit of energy. Auburn researchers are working on woody biomass, bioenergy crops such as switchgrass and non-food oil seed crops. Optimal biomass harvesting techniques are being developed and new processing technologies are being evaluated to determine efficient forms of material composition for delivery to a processing point. More efficient and technologically advanced harvesting systems are needed to ensure that biomass feedstocks can be produced at least cost. Auburn researchers are working on rapid on-line measurement of biomass properties that are critical to biorefinery.
More efficient biomass transportation systems, preprocessing and infrastructure will be designed to provide lowest cost biomass delivered to the final processing plants. Separation of various raw materials should be evaluated to determine the need and potential to mix and co-process various forms of biomass feedstock. Additional work is being focused on advanced logistics techniques using the latest technologies to optimize transportation of biomass feedstocks. Research is being conducted to preprocess biomass at high moisture content and finding ways to minimize energy consumption during biomass grinding process.
Syngas is an essential building block to liquid fuels and petrochemicals using catalytic processes such as the ammonia, methanol, and Fischer-Tropsch synthesis. Hydrogen from syngas is also used in power generation. Carbon monoxide from syngas is also used in the production of metals from ores and chemicals such as acetic acid, phosgene, synthetic fatty acids, and acrylic acid. Syngas conversion catalysts are highly intolerant to foreign species (tar, sulfur, halogens, heavy metals etc.) and research identifying more productive and cost effective syngas cleanup technologies is ongoing.
Research at the center focuses on the development of syngas cleanup and conversion as well as product upgrading catalysts. Catalysts are essential in the cleanup of syngas and production of liquid fuels (diesel, jet fuel, and gasoline) and chemicals (hydrogen, iso-butane, alcohols, wax etc.) from biomass, coal, and natural gas derived syngas. Also, in recent years, the process development focus has shifted away from “economy-of-scale” commercial plants to modular product tailored units. In Fischer-Tropsch synthesis for instance, this shift has opened the opportunity to develop new catalysts and reactor processes producing a narrower product slate (i.e. narrower hydrocarbon distribution aimed at kerosene and diesel instead of methane to heavy waxes). Other focus areas, among other, includes isomerization (n-alkanes to iso-paraffins), hydrotreating (contaminant removal), as well as other octane enhancing reactions including reforming and alkylation.
Research in alternative fuels is multidisciplinary in nature ranging from raw material production to transportation logistics to energy conversion systems. This offers a unique opportunity for the faculty and students in different colleges to collaborate and be involved in a process from conception of an idea to research and development of the idea, and ultimately commercialization. The components of this initiative in education and outreach consist of three main areas: interdisciplinary curriculum development, K-12 and public outreach, and technology transfer.
We need to know the rates of biomass production that can be sustained and how these can be maximized. Issues such as site productivity, water quality, and other factors will need to be addressed. Also, any potential environmental impacts associated with manufacturing and production processes will need to be clarified and minimized as well. It is critical that we understand how rapidly our state's resources of woody and agricultural biomass can be replenished as well as the obstacles to maximum production. Although Alabama climate is generally conducive to high production rates, we often fall far short of maximum production due to restricted soil productivity. Repeated intensive harvests will increase demands on soils and, consequently, we must understand how to maintain and increase site productivity within a framework of economically viable options. The natural biomass resources of Alabama can supply enormous amounts of energy; however, in order to permanently reduce our dependence on foreign oil, we must ensure sustainable biomass production. The conversion of Alabama's natural resources to fuels, power, or chemicals requires manufacturing facilities that have potential negative environmental impact in the form of air emissions, liquid effluent, and solid waste. These impacts need to be reduced to the absolute minimum by a combination of in-plant controls and end-of-pipe treatment, which simultaneously recover by-product value from waste streams and eliminate all potentially harmful environmental effects. The guiding principles are embedded in the disciplines of sustainable engineering and green chemistry. One of the chief sources of revenue derived from natural resources in Alabama is leasing of lands for hunting. Broader cultivation of biomass crops and forest extractions may have positive or negative implications for wildlife habitat at small scales. Consequently, we need to understand how biomass production may affect the value of land for leases so that landowner revenues can be maximized.