Repository logo

A probabilistic and environmental impact assessment of a cyanobacteria-based biorefinery

dc.contributor.authorBeattie, Audrey, author
dc.contributor.authorQuinn, Jason C., advisor
dc.contributor.authorArabi, Mazdak, committee member
dc.contributor.authorMarchese, Anthony, committee member
dc.description.abstractMicrobial based biofuels represent a potential promising solution as an environmentally favorable transportation fuel. Cyanobacteria have many of the same advantages as microalgae: ability for rapid growth in otherwise non-arable regions, suitability for genetic engineering, and simple nutritional needs. Additionally, cyanobacteria can be engineered to secrete valuable co-products that can be harvested independent from the produced biomass. However, little work has been done to identify the processes and the economic and environmental impacts associated with a large-scale cyanobacteria-to-fuels facility. The present study is a concurrent techno-economic and life cycle assessment of a facility that generates fuels and methyl laurate, an oleochemical, from the cyanobacterial species Synechocystis sp. PCC 6803. The biorefinery model includes all aspects of cultivation, separation of the secreted methyl laurate, biomass harvesting and fuel processing via hydrothermal liquefaction (HTL) of the dewatered biomass. The assessments leverage Monte Carlo analysis (MCA) to address uncertainty and variability inherent in the most significant input parameters, replacing them with probabilistic functions. For the facility configuration producing both fuels and the oleochemical co-product, the MCA average minimum fuel selling price (MFSP) is $2.47 per liter or $9.34 per gallon of gasoline equivalent (gge) with the corresponding average global warming potential determined to be 118 g CO2-eq/MJ-1. The case producing only fuels results in an MCA average MFSP of $2.01/L-1 ($7.60/gge) and an average environmental impact of 100 g CO2-eq/MJ-1. These results are compared to static optimistic and conservative scenario analysis estimates, illustrating the over- and under-estimation of outcomes associated with non-stochastic methods. Suggested facility improvements include increases in pond productivity of both the biomass and methyl laurate oil production, as well as improvements to carbon utilization and bio-crude yield from HTL processing.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.publisherColorado State University. Libraries
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see
dc.subjectmethyl laurate
dc.subjecttechno-economic analysis
dc.subjectlife cycle assessment
dc.subjectMonte Carlo analysis
dc.titleA probabilistic and environmental impact assessment of a cyanobacteria-based biorefinery
dcterms.rights.dplaThis Item is protected by copyright and/or related rights ( You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). Engineering State University of Science (M.S.)


Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
1.37 MB
Adobe Portable Document Format