Techno-Economic Assessment of Atmospheric Carbon Removal via Industrial Composting of Biomass Waste with CO_<b>2</b> Capture

The techno-economic feasibility of removing atmospheric CO₂ via industrial composting of high-moisture, heterogeneous biomass waste with CO₂ capture is assessed. The novel composting process generates a relatively high concentration of biogenic CO₂ for capture, while avoiding the emission of methane and generating a nutrient-rich soil amendment. Empirical data generated from compost bioreactors at 0.5 L and 25 L scales inform the techno-economic assessment. The levelized cost of CO₂ capture is estimated to be USD 85 per tonne of CO₂ (tCO₂), while the levelized cost of CO₂ removal is estimated to be USD 102/tCO₂ under base case assumptions. Sensitivity analysis indicates that a biomass feed rate and tipping fee are the most sensitive parameters. A compost facility with a biomass feed rate of 45,990 dry t-biomass/year has the potential to remove over 26,500 tCO₂/year from the atmosphere with gaseous CO₂ capture. Industrial composting of biomass waste with CO₂ capture has the potential to be a viable biomass carbon removal and storage (BiCRS) technology and warrants further investigation.