Title: The importance and the challenges of characterizing the rheology of lignocellulosic biomass
Date and Time: Friday, May 24. Refreshments served at 3:15 p.m. Seminar starts at 3:30 p.m.
Location: Chemical & Biological Engineering Rm 102
Abstract
This seminar will focus on the rheology of plant-based materials, specifically lignocellulosic biomass, and address both the importance of rheology to industrial processing of these materials, and the significant challenges that exist to their rheological characterization. Industrial processing of lignocellulosic biomass has a long history, especially in the pulp and paper industry, but increasing interest in producing renewable fuels and chemicals from biomass has led to increasingly complex chemical processing schemes that strongly influence biomass rheological properties in complex ways.
Unit operations such as auto-hydrolysis, dilute-acid hydrolysis, enzymatic hydrolysis, and others, have been developed to break down the complex network of lignocellulose into simpler molecules for future processing, but during such processing steps the rheological properties of the materials, and therefore the ability to pump, pour, and mix them, change with time. Understanding the dependence of rheological properties on reaction variables such as time, temperature, reactant concentration, and others, is especially important at the plant/facility design stage where pumps, piping, and reactors need to be sized based on material physical properties. Unfortunately, accurate rheological measurements on lignocellulosic biomass are often elusive due to practical rheological challenges associated with the fibrous nature of the materials and the strong dependence of rheological properties on physical variables that tend to vary from one biomass sample to the next. Obtaining useful rheological data for designing industrial processes requires a careful selection of rheometer geometry, a well-designed experimental protocol, and the application of a proper constitutive model to capture the complex rheology.
In this seminar, the challenges in characterizing the rheology of lignocellulosic biomass at various stages of processing will be discussed, as will recent efforts to make and use measurements of time-dependent rheological properties of dilute-acid hydrolyzed corn stover to predict pressure losses in processing equipment.
Biography
Joseph Samaniuk is an associate professor in the Department of Chemical and Biological Engineering at the Colorado School of Mines. His research group focuses on the rheology and dynamics of a wide range of soft matter systems. Current projects include the study of the time-dependent rheological properties of dilute-acid hydrolyzed corn stover, the study of the dynamics of two-dimensional particles confined to rheologically-complex fluid-fluid interfaces, and the development of novel microrheological techniques.
Joe’s MS and BS degrees in Chemical Engineering were earned at Virginia Tech, and he obtained his PhD in Chemical Engineering at the University of Wisconsin-Madison while studying the rheology of lignocellulosic biomass. He was awarded a Pegasus Marie Curie Postdoctoral Fellowship from the Belgian science foundation Fonds Wetenschappelijk Onderzoek (FWO) to investigate the use of microrheological methods at fluid-fluid interfaces in the Department of Chemical Engineering at KU Leuven.
His second postdoctoral position was in the Materials Science Department at ETH Zürich where he continued to study the dynamics and rheology of complex fluid-fluid interfaces. In 2016 he joined the department at the Colorado School of Mines as an assistant professor, and in 2020 he received the National Science Foundation’s CAREER Award from the Particulate and Multiphase Processes Program.