Journal of Industrial Microbiology & Biotechnology

, Volume 37, Issue 11, pp 1157–1168 | Cite as

Techno-economic analysis of biomass to fuel conversion via the MixAlco process

Original Paper


MixAlco is a robust process that converts biomass to fuels and chemicals. A key feature of the MixAlco process is the fermentation, which employs a mixed culture of acid-forming microorganisms to convert biomass components (carbohydrates, proteins, and fats) to carboxylate salts. Subsequently, these intermediate salts are chemically converted to hydrocarbon fuels (gasoline, jet fuel, and diesel). This work focuses on process synthesis, simulation, integration, and cost estimation of the MixAlco process. For the base-case capacity of 40 dry tonne feedstock per hour, the total capital investment is US $5.54/annual gallon of hydrocarbon fuels (US $3.79/annual gallon of ethanol equivalent), and the minimum selling price [with 10% return on investment (ROI), internal hydrogen production, and US $60/tonne biomass] is US $2.56/gal hydrocarbon, which is equivalent to US $1.75/gal ethanol. If plant capacity is increased to 400 tph, the minimum selling price of biomass-derived hydrocarbon fuels is US $1.76/gal hydrocarbon (US $1.20/gal ethanol equivalent), which can compete without subsidies with petroleum-derived hydrocarbons when crude oil sells for about US $65/bbl. At 40 tph, using the average tipping fee for municipal solid waste (US $45/dry tonne) and current price of external hydrogen (US $1/kg), the minimum selling price is only US $1.24/gal hydrocarbon (US $0.85/gal ethanol equivalent).


MixAlco Techno-economic analysis Simulation Design Biofuel Cost estimation Sensitivity analysis 



The authors gratefully acknowledge the sponsorship and collaborations of Dr. Cesar Granda, DARPA, Logos Tech, Terrabon, Valero, and Waste Management.

Legal disclaimer

Except as expressly referenced in this paper, the information, estimates, projections, calculations, and assertions expressed in this paper have not been endorsed, approved, or reviewed by any unaffiliated third party, including Terrabon, Inc., and are based on the authors’ own independent research, evaluation, and analysis. The views and opinions of the authors expressed herein do not state or reflect those of such third parties, and shall not be construed as the views and opinions of such third parties.


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Copyright information

© Society for Industrial Microbiology 2010

Authors and Affiliations

  • Viet Pham
    • 1
  • Mark Holtzapple
    • 1
  • Mahmoud El-Halwagi
    • 1
  1. 1.Department of Chemical Engineering, 3122 TAMUTexas A&M UniversityCollege StationUSA

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