Preventing Aerosol Emissions in a CO2 Capture System: Combining Aerosol Formation Inhibition and Wet Electrostatic Precipitation

Aerosol emission from the CO₂ capture system has raised great concern for causing solvent loss and serious environmental issues. Here, we propose a comprehensive method for reducing aerosol emissions in a CO₂ capture system under the synergy of aerosol formation inhibition and wet electrostatic precipitation. The gas-solvent temperature difference plays a vital role in aerosol formation, with aerosol emissions of 740.80 mg/m³ at 50 K and 119.36 mg/m³ at 0 K. Different effects of SO₂ and SO₃ on aerosol formation are also found in this research; the aerosol mass concentration could reach 2341.25 mg/m³ at 20 ppm SO₃ and 681.01 mg/m³ at 50 ppm SO₂ with different aerosol size distributions. After the CO₂ capture process, an aerosol removal efficiency of 98% can be realized by electrostatic precipitation under different CO₂ concentrations. Due to the high concentration of aerosols and aerosol space charge generated by SO₂ and SO₃, the removal performance of the wet electrostatic precipitator decreases, resulting in a high aerosol emission concentration (up to 130.26 mg/m³). Thus, a heat exchanger is installed before the electrostatic precipitation section to enhance aerosol growth and increase aerosol removal efficiency. Under the synergy of aerosol formation inhibition and electrostatic precipitation, an aerosol removal efficiency of 99% and emission concentrations lower than 5 mg/m³ are achieved, contributing to global warming mitigation and environmental protection.