Discipline: Ecology, Environmental & Earth Sciences
Subcategory: STEM Research
Abolghasem Shahbazi - North Carolina A&T State University
Co-Author(s): Dr. Lijun Wang, North Carolina A&T State University, Greensboro, NC; Dr. Debasish Kuila, North Carolina A&T State University, Greensboro, NC
The combination of biomass gasification and subsequent Fischer Tropsch (FT) synthesis is a promising pathway to produce renewable, low carbon liquid fuels and chemicals. Biomass gasification in a fluidized bed gasifier involves complicated physicochemical and structure evolution of biomass particles, and reactive gas-particle behavior. The impurities in syngas such as nitrogen and tar can severely interfere with downstream catalytic reactions involved in syngas utilization. This project investigates an integrated biomass gasification and FT synthetic process to produce liquid fuels from biomass. Five studies have been conducted, which include (1) experimental determination and mathematical modeling of physicochemical and structural evolution of biomass particles during gasification; (2) computational fluid dynamics (CFD) modeling of the multiphase reactive gas-particle flow behavior in a biomass fluidized bed gasifier; (3) investigation of a nickel-based catalyst for tar cracking and ammonia decomposition of hot syngas; (4) study of Fe-based and bimetallic catalysts for the F-T synthesis of liquid fuels from biomass-derived syngas with enriched CO2 in tubular and microchannel reactors, and (5) process simulation of the biomass-to-liquid fuel refinery. Advanced experimental and mathematical modeling techniques are used to generate fundamental knowledge and tools necessary for the development of a biomass-to-liquid fuel refinery based on gasification and FT synthesis. Specifically, experimental techniques including TGA-DSC, Frontier micropyrolyzer, elemental analyzer, GC-MS and infrared spectrometry are used to uncover the physicochemical evolution of biomass particles during gasification. Also, a two-phase theory model in conjunction with detailed kinetics of biomass pyrolysis and gasification was developed to simulate the hydrodynamics of a bubbling fluidized bed gasifier. Effect of heat transfer between bubble and emulsion phase on composition and concentration of different classes of tars is shown at different operating conditions. Nickel-based catalysts are investigated to catalytically remove tar and ammonia from the syngas. Bimetallic cobalt-based catalyst 10%Co 5%Fe MCM-41 were synthesized using the one-pot hydrothermal method and used to investigate conversion of syngas to higher alkanes using 3D-printed stainless steel microreactors. A mathematical model is developed in Aspen Plus and Gabi 6 to analyze the techno-economics and assess the environmental impacts of the refinery.
Funder Acknowledgement(s): This study was fully supported by NSF Grant # HRD 1242152 and HRD 1736173, awarded to the CREST Center for Bioenergy at NC A&T State University. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the funding agency
Faculty Advisor: None Listed,
NSF Affiliation: CREST