Techno-Economic Evaluation of Synthetic Natural Gas Production Based on Biomass Gasification with CO2 Capture

Abstract

Integrating renewable energy sources and CO₂ capture and utilisation technologies will result in energy conversion systems with negative carbon emissions (CO₂ is removed from the atmosphere, reducing its concentration). Accordingly, synthetic fuels produced from renewables will gradually replace conventional fossil-based ones. This work evaluates the techno-economic implications of Synthetic Natural Gas (SNG) production from biomass (e.g., sawdust, agricultural and municipal wastes etc.) gasification with CO₂ capture using gas-liquid absorption. The evaluated concept has a capacity of 500 MW_th synthetic natural gas with about 60 % CO₂ capture rate. The mass and energy balances of simulated integrated designs were then used to quantify the key performance indicators. A detailed techno-economic and environmental analysis underlines the promising potential of SNG production based on biomass gasification with CO₂ capture feature: high cumulative energy efficiency (about 69 %), low specific CO₂ emissions (up to 3 kg/MWh as process emission and negative emissions for the overall system), the co-generation capability of SNG and decarbonized power as well as improved economic indicators in terms of capital investment, operational costs and SNG production cost.