Fuel from microalgae

Nagle, N. P. Lemke. Production of methyl ester fuel from microalgae. Appl. Biochem. Biotechnol. 1990,355-361. 

Figure 6.1 An overall framework showing major operations for obtaining fuels from microalgae. Reproduced with permission from R. Ubando...

The oleaginous nature of microalgae allows them to biosynthesize lipids with a commercial interest for biofuel, nutritional supplements, and pharmaceutical applications. Generating biodiesel, bioethanol, and bio jet fuel from microalgae as a replacement for their fossil fuel-based coxmterparts has been an ongoing quest since the early 1960s and has been explored in... 

Roessler, P.G., Brown, L.M., Dunahay, T.G., Heacox, D.A., Jarvis, E.E., Schneida-, J.C., Talbot, S.G., Zeiler, K.G., 1994. Genetic engineering approaches for enhanced production of biodiesel fuel from microalgae. ACS Symp. Ser. 566, 255-270 (Enzymatic conversion of biomass for fuels production). 

A. M. Hill and D. A. Feinberg, Fuel Products from Microalgae, SERI/TP-231-2348, Solar Energy Research Institute, Golden, Colo., 1984. 

Feinberg DA (1984) Technical and economic analysis of liquid fuel production from microalgae. DOE Report SERI/TP-231-2608. Solar Energy Research Institute, Golden, CO... 

The technology for triglyceride production from microalgae has not yet been commercialized. Most of the economic analyses for the production of microalgal liquids reported in the literature indicate they are much too expensive to compete with petroleum fuels. Considerable additional research must be carried out to perfect the process despite the fact that research on microalgal fuel production has been in progress for at least the past two decades. 

Hill, A. M., and Feinberg, D. A. (1984). Fuel Products from Microalgae, SER17TP-231-2348. National Renewable Energy Laboratory, Golden, CO. 

Benemann, J.R., et a "A Systems Analysis of Bioconversion with Microalgae", "Symposium Papers", Clean Fuels from Biomass and Wastes, Symposium sponsored by the Institute of Gas Technology, Orlando, Fla., Jan. 25-28, 1977 Institute of Gas Technology Chicago. 1977 pp 101-26. 

It has been concluded that microalgal biodiesel is the only renewable biodiesel that has the potential to completely displace liquid transport fuels derived from petroleum. Existing demand for liquid transport fuels could be met sustainably with biodiesel from microalgae, but not with bioethanol from sugarcane (17). 

Johnson MB, Wen Z. Production of biodiesel fuel from the microalga Schizochytrium limacinum by direct transesterification of algal biomass. Energy Fuels 2009 23 5179. 

Liang Y. Producing liquid transportation fuels from heterotrophic microalgae. Appl Energy 2013 104 860. 

Dote Y, Sawayama S, Inoue S, Mino aT,Yokoyama S. Recovery of liquid fuel from hydrcarbon-rich microalgae by thermochemical hquefaction. Fuel 1994 73 1855. 

Currently, the main raw materials used to produce biodiesel are the vegetable oils extracted from oleaginous plants. The cost of these materials currentiy represents about 70% of the total production costs. This means that the most suitable vegetable oils are those from crops with the highest productivity per hectare or low-cost oils such as waste oils. These days, the high fossil fuel prices, the collapse of food for biodiesel initiatives, and concerns about increased levels of CO2 emissions in the atmosphere have all created awareness of the need for alternative fuel solutions. Microalgae have optimistically emerged as one of the potential lowest-cost feedstocks for biodiesel production (Robles-Medina et al., 2009). 

Cherad, R., et al., 2015. Hydrogen production from the catalytic hydrothermal gasification of process water from microalgae hquefaction. Fuel 166, 24—28. 

Dote, Y., et al., 1994. Recovery of hquid fuel from hydrocarbon-rich microalgae by thermo-chemical liquefaction. Fuel 73 (12), 1855—1857. 

Ou, L., et al., 2015. Techno-economic analysis of transportation fuels from defatted microalgae via hydrothermal liquefaction and hydroprocessing. Biomass and Bioenergy 72 (0), 45-54. 

The oil obtained from microalgae usually has a higher viscosity than diesel oil, which cannot be directly applied to engines. Transesterification is needed to reduce the viscosity and increase the fluidity. Transesterification occurs stepwise with the first conversion of TAG to DAG and then to MAG and finally to glycerol. In this process, large, branched triglycerides are transformed into smaller, straight-chain molecules, which are similar in size to the molecules of the species present in diesel fuel (Sinha et al., 2008). 

Microalgae and oilseed crops can provide diesel fuel. The use of these alcohol fuels can reduce air pollution. Methane made from anaerobically digested manure was used to light streets in England as early as 1895. Anaerobic digestion is also used to produce fertilizers. 

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