Techno-economic assessment of calcium and magnesium-based sorbents for post-combustion CO2 capture applied in fossil-fueled power plants

Abstract

This work evaluates the most relevant techno-economic performances of calcium and magnesium-based sorbents used in high temperature solid looping cycles for post-combustion CO2 capture applied in fossil power generation. The evaluated power plants generate 1000 MW net electricity with 90% CO2 capture rate. As fuels, natural gas was assessed for combined cycle power plants since coal and lignite were assessed for super-critical power plants. As comparison benchmark systems, the correspondent plants with non-capture feature and with carbon capture using reactive gas–liquid absorption were also assessed. As the results show, both calcium and magnesium carbonate looping concepts applied in solid fossil fuel super-critical plants induce lower carbon capture energy penalty compared to the reactive gas–liquid absorption by about 1–2.2 net efficiency percentage points. The Calcium Looping (CaL) cycle shows higher net power efficiency than the Magnesium Looping (MgL) cycle by about 1–1.4 net percentage points. In case of natural gas combined cycle plants, the chemical absorption system has higher net power efficiency than CaL and MgL systems by about 4–6 percentage points. The key economic indicators (e.g., electricity production cost, CO2 capture costs etc.) show that both evaluated carbonate looping systems perform better than amine-based chemical scrubbing.