Arrested anaerobic digestion (AAD) is a process that inhibits methane formation while bacteria break down organic matter without oxygen. AAD can potentially produce carbon-negative chemicals and biofuels from organic waste. Three technical hurdles, however, have limited AAD’s widespread commercial success: (1) limited system capacity for processing diverse solid and liquid feedstocks of varying quality and composition, (2) resistance to variations in feedstock input over time, and (3) greater energy consumption needed for separation than the lower heating value of the produced volatile fatty acids (VFAs), precluding their use for biofuels production.
Project Innovation + Advantages:
The National Renewable Energy Laboratory (NREL) aims to develop the first carbon negative biorefinery that funnels multiple organic waste feedstocks into a chemically consistent stream of volatile fatty acids (VFAs) that are upgraded to carbon negative products. NREL’s Recirculating System for Optimal Use of Refuse with Control and Efficiency (ReSOURCE) process operates via arrested anaerobic digestion, and it accumulates and selectively isolates VFAs. The VFA products serve as robust platform chemicals to subsequently produce sustainable aviation fuel, lubricants, and cleaning surfactant substitutes.
ReSOURCE would represent a first-of-a-kind system to produce biochemicals from multiple organic wet waste feedstocks.
ReSOURCE can access ~120 kilotons/year of U.S.-based organic waste feedstocks by including solid food waste, manure, and yard waste (equating to ~11 billion gallons of biofuel potential or ~20% of U.S. sustainable aviation fuel demand).
ReSOURCE will enable a broad range of organic waste to be funneled to biofuels and biochemicals, rather than landfilled where it would result in atmospheric methane emissions.
ReSOURCE’s feedstock flexibility combined with the low energy consumption of the novel separation system provide a disruptive technology to make carbon negative products from organic wastes cost competitive with commodity fuels and chemicals.