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Title: Online residence time distribution measurement of thermochemical biomass pretreatment reactors

Journal Article · · Chemical Engineering Science

Residence time is a critical parameter that strongly affects the product profile and overall yield achieved from thermochemical pretreatment of lignocellulosic biomass during production of liquid transportation fuels. The residence time distribution (RTD) is one important measure of reactor performance and provides a metric to use when evaluating changes in reactor design and operating parameters. An inexpensive and rapid RTD measurement technique was developed to measure the residence time characteristics in biomass pretreatment reactors and similar equipment processing wet-granular slurries. Sodium chloride was pulsed into the feed entering a 600 kg/d pilot-scale reactor operated at various conditions, and aqueous salt concentration was measured in the discharge using specially fabricated electrical conductivity instrumentation. This online conductivity method was superior in both measurement accuracy and resource requirements compared to offline analysis. Experimentally measured mean residence time values were longer than estimated by simple calculation and screw speed and throughput rate were investigated as contributing factors. In conclusion, a semi-empirical model was developed to predict the mean residence time as a function of operating parameters and enabled improved agreement.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Sustainable Transportation Office. Bioenergy Technologies Office
Grant/Contract Number:
AC36-08GO28308; AC36-08-GO28308
OSTI ID:
1227702
Alternate ID(s):
OSTI ID: 1358921
Report Number(s):
NREL/JA-5100-63452
Journal Information:
Chemical Engineering Science, Vol. 140; Related Information: Chemical Engineering Science; ISSN 0009-2509
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 20 works
Citation information provided by
Web of Science

References (12)

Modeling and optimization of the dilute-sulfuric-acid pretreatment of corn stover, poplar and switchgrass journal February 1997
Residence-time distribution model for twin-screw extruders journal December 1999
One-line measurement of the residence time distribution in screw extruders journal May 1999
Notes on the diffusion-type model for the longitudinal mixing of fluids in flow journal April 1957
Features of promising technologies for pretreatment of lignocellulosic biomass journal April 2005
Dilute acid pretreatment of softwoods: Scientific note journal March 1998
Residence time distributions of coarse biomass particles in a screw conveyor reactor journal February 2015
Residence time distribution (RTD) in aseptic processing of particulate foods: a review journal January 1995
Dilute-Sulfuric Acid Pretreatment of Corn Stover in Pilot-Scale Reactor: Investigation of Yields, Kinetics, and Enzymatic Digestibilities of Solids journal January 2003
Data smoothing and numerical differentiation by a regularization method journal April 2010
Measurement of residence time distribution of a multicomponent system inside an ohmic heater using radio frequency identification journal August 2009
Flow characteristics of biomass particles in a horizontal stirred bed reactor: Part I. Experimental measurements of residence time distribution journal January 2015

Cited By (2)

Assessing pretreatment reactor scaling through empirical analysis journal October 2016
Comparison of computational fluid dynamics–discrete element method and discrete element method simulations for a screw conveyor journal December 2019