Process design and economics of on-site cellulase production on various carbon sources in a softwood-based ethanol plant.

Research output: Contribution to journalArticle


On-site cellulase enzyme fermentation in a softwood-to-ethanol process, based on S -catalysed steam pretreatment followed by simultaneous saccharification and fermentation, was investigated from a techno-economic aspect using Aspen Plus and Aspen Icarus Process Evaluator softwares. The effect of varying the carbon source of enzyme fermentation, at constant protein and mycelium yields, was monitored through the whole process. Enzyme production step decreased the overall ethanol yield (270 L/dry tonne of raw material in the case of purchased enzymes) by 5–16 L/tonne. Capital cost was found to be the main cost contributor to enzyme fermentation, constituting to 60–78% of the enzyme production cost, which was in the range of 0.42–0.53 SEK/L ethanol. The lowest minimum ethanol selling prices (4.71 and 4.82 SEK/L) were obtained in those scenarios, where pretreated liquid fraction supplemented with molasses was used as carbon source. In some scenarios, on-site enzyme fermentation was found to be a feasible alternative.


External organisations
  • Budapest University of Technology and Economics
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Chemical Engineering
Original languageEnglish
Number of pages8
JournalEnzyme Research
Publication statusPublished - 2010
Publication categoryResearch