THIS PROJECT IS PROPOSED BY FLORIDA INSTITUTE OF TECHNOLOGY (FIT) LEVERAGING IDAHO NATIONAL LABORATORY'S (INL) FACILITIES OF BIOMASS PREPROCESSING TECHNOLOGIES. THE OVERARCHING GOAL IS TO UPGRADE HIGH-ASH BIOMASS INTO LOW-ASH, MASS AND ENERGY DENSE, AND PELLETIZED BIOREFINERY FEEDSTOCKS. THE GOAL WILL BE ACCOMPLISHED VIA SYSTEMATIC EXPERIMENTS AT SEMI-BATCH SCALE TO CONTINUOUS SCALE AND A DETAILED TECHNOECONOMIC ANALYSIS OF A FULL-SCALE UNIT.HIGH-ASH BIOMASS WILL BE COLLECTED FROM INL'S PROVEN AIR CLASSIFICATION (AC) TECHNOLOGY. MILD HYDROTHERMAL PREPROCESSING (MHP) WILL BE PERFORMED ON THIS HIGH-ASH FRACTION (HAF) BIOMASS REJECT FROM AC TO REDUCE STRUCTURAL INORGANICS. MHP USES SUBCRITICAL WATER, WHICH REACTS WITH BIOMASS AND LEACHES INORGANICS DUE TO ITS UNIQUE THERMODYNAMIC PROPERTIES. HYDROCHAR, THE RESULTED LOW ASH BIOMASS FROM MHP, ALSO HAS BINDING ABILITY, WHICH WILL BE EXPLORED TO PELLETIZE LOW-ASH FRACTION OF AC TECHNOLOGY IN SINGLE-PRESS PELLET PRESS (AT FIT) AND PELLET MILL (AT INL). FINALLY, A DETAILED TECHNOECONOMIC ANALYSIS OF INTEGRATED AC, MHP, AND PELLETIZATION PROCESSES WILL BE PERFORMED WITH INL'S GUIDANCE.BY THE END OF THIS PROJECT, WE WILL HAVE A BETTER UNDERSTANDING OF (A) HOW TO REMOVE STRUCTURAL INORGANICS USING MHP TECHNOLOGY, (B) THE PELLETIZATION PROPERTIES OF HYDROCHAR AND OPTIMUM CONDITION FOR BIOMASS PALLETIZATION USING MHP HYDROCHAR, AND (C) ECONOMIC FEASIBILITY OF THE HIGH-ASH BIOMASS PREPROCESSING TECHNOLOGIES. MHP IS A UNIQUE PREPROCESSING TECHNOLOGY THAT HAS TRANSFORMATIVE POTENTIALS TO IMPROVE BIOREFINERY FEEDSTOCK LOGISTICS ECONOMICS, THEREFORE, THIS PROJECT ALIGNS WELL WITH THE SCOPE OF PROGRAM AREA A1414 BIOENERGY AND BIOBASED PRODUCT FEEDSTOCK LOGISTICS.