Abstract:
:Cellulose fibers in water form networks that give rise to an apparent yield stress, especially at high solids contents. Measuring the yield stress and correlating it with fiber concentration is important for the biomass and pulp industries. Understanding how the yield stress behaves at high solids concentrations is critical to optimize enzymatic hydrolysis of biomass in the production of biofuels. Rheological studies on pretreated corn stover and various pulp fibers have shown that yield stress values correlate with fiber mass concentration through a power-law relationship. We use magnetic resonance imaging (MRI) as an in-line rheometer to measure velocity profiles during pipe flow. If coupled with pressure drop measurements, these allow yield stress values to be determined. We compare our results with literature values and discuss the accuracy and precision of the rheo-MRI measurement, along with the effects of fiber characteristics on the power-law coefficients.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Lavenson DM,Tozzi EJ,McCarthy MJ,Powell RLdoi
10.1002/bit.23197subject
Has Abstractpub_date
2011-10-01 00:00:00pages
2312-9issue
10eissn
0006-3592issn
1097-0290journal_volume
108pub_type
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