**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** BIOREFINING OF RENEWABLE FEEDSTOCKS TO BENEFICIAL PRODUCTS IS A CORNERSTONE OF CIRCULAR BIOECONOMIES.FARMERS ARE KEY STAKEHOLDERS IN CIRCULAR BIOREFINING, PROVIDING SUBSTRATES (E.G., MANURE, PLANT RESIDUES) AND SITES FOR PROCESSING FACILITIES. ANAEROBIC DIGESTION RELIES ON MICROBIAL COMMUNITIES TO CONVERT ORGANIC MATERIALS INTO BIOGAS, A MIXTURE OF CARBON DIOXIDE, METHANE, AND OTHER TRACE GASSES. THE BIOGAS IS EITHER COMBUSTED TO GENERATE ELECTRICITY OR CONVERTED TO PIPELINE-QUALITY NATURAL GAS THROUGH A SERIES OF GAS CLEANING STEPS. WHILE ANAEROBIC DIGESTION CAN RECOVER ENERGY AND CARBON FROM MANURE, THE ECONOMIC VIABILITY OF ON-FARM ANAEROBIC DIGESTION IS NOT GUARANTEED. WHILE SEVERAL FATORS IMPACT THE SUCCESS OF AN ANAEROBIC DIGESTION PROJECT, A KEY DETERMINANT IS THE VALUE OF THE FINAL PRODUCT. THE LONG-TERM GOAL OF THE PROPOSED PROJECT IS TO EXPAND THE PRODUCTS FROM ANAEROBIC BIOPROCESSING OF AGRICULTURAL WASTES AND ENABLE FARMS TO BECOME SUSTAINABLE HUBS IN CIRCULAR BIOECONOMIES.WITH THE LACK OF NATURAL GAS INFRASTRUCTURE IN RURAL AREAS THROUGHOUT THE UNITED STATES, NEW PRODUCTS FROM BIOREFINING OF AGRICULTURAL WASTES COULD ENHANCE THE ECONOMIC VIABILITY OF AGRICULTURAL SYSTEMS. PROPANE IS USED AS A FUEL THROUGHOUT MUCH OF RURAL AMERICA.THE MAJOR DRIVER FOR SELECTING EITHER HEATING OIL OR PROPANE AS A FUEL IS COST. PRICES FOR PROPANE HAVE INCREASED IN THE PAST TEN YEARS AND THE CURRENT PRICE IN US AVERAGE IS CURRENTLY $2.30 PER GALLON.NEARLY ALL OF THE PROPANE USED IN THE UNITED STATES IS DERIVED FROM FOSSIL FUEL REFINING. IN THE PROPOSED WORK, WE WILL INVESTIGATE FACTORS THAT INCREASE THE PRODUCTION OF PROPANE FROM COMBINATIONS OF COW MANURE AND FOOD WASTE AND EVALUATE THE LIFE CYCLE IMPACTS OF THIS APPROACH COMPARED TO CONVENTIONAL PROPANE PRODUCTION.