School of Civil and Environmental Engineering

Ph.D. Thesis Defense Announcement

CHARACTERIZATION OF PHYSICAL AND RHEOLOGICAL PROPERTIES OF PARTICULATED NON-RECYCLABLE MUNICIPAL SOLID WASTE (NMSW) AND WOODY BIOMASS

By Abdallah Ikbarieh

Advisor:

Dr. Sheng Dai

Committee Members:

Dr. Susan Burns (CEE/GT), Dr. David Frost (CEE/GT), Dr. Carlos Santamarina (CEE/GT), Dr. Wencheng Jin (PE/TAMU)

Date and Time: April 3, 2026, 12 PM

Location: SEB122

ABSTRACT
Biofuels from biomass, such as non-recyclable municipal soil waste (NMSW) and woody biomass, present a promising alternative to fossil fuels, offering the potential to significantly reduce greenhouse gas emissions and dependence on unsustainable disposal methods. However, widespread adoption of biofuels from biomass is hampered by persistent feedstock handling during storage, pretreatment, and transport prior to conversion. Poorly designed handling equipment, such as hoppers, screw feeders, and solid pumps, can lead to flow obstructions, jamming, process interruptions, equipment downtime, and thus, reduced efficiency of biofuels production. Addressing these issues requires a fundamental understanding and precise characterization of the physical and rheological properties of the feedstock that govern material handling and equipment design.This thesis delves into characterizing the compressibility, permeability, shear strength, and flow behavior of NMSW and woody biomass through a combined experimental, numerical, and data-driven framework. The work develops a semi-empirical model to predict the permeability of blended NMSW mixtures, customizes an ultra-fast vane shear device tailored to understand the stress- and rate-dependent shear strength of NMSW materials across different flow regimes, establishes a machine learning-based model to characterize flowing woody biomass through hoppers considering physical properties of particles and industrial-scale hopper attributes, and lastly, explores advanced modeling of the complex flow behavior of NMSW particles through hoppers.
This research advances the fundamental understanding of the mechanics and rheology of particulate NMSW and woody biomass in material handling applications and supports the design of trouble-free feedstock handling equipment for increased biofuel production.