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

Abstract

Aerosol emission from the CO 2 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 CO 2 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/m 3 at 50 K and 119.36 mg/m 3 at 0 K. Different effects of SO 2 and SO 3 on aerosol formation are also found in this research; the aerosol mass concentration could reach 2341.25 mg/m 3 at 20 ppm SO 3 and 681.01 mg/m 3 at 50 ppm SO 2 with different aerosol size distributions. After the CO 2 capture process, an aerosol removal efficiency of 98% can be realized by electrostatic precipitation under different CO 2 concentrations. Due to the high concentration of aerosols and aerosol space charge generated by SO 2 and SO 3 , the removal performance of the wet electrostatic precipitator decreases, resulting in a high aerosol emission concentration (up to 130.26 mg/m 3 ). 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/m 3 are achieved, contributing to global warming mitigation and environmental protection.

Reducing Aerosol Emissions by Decoupled Parameter Management during the CO2 Capture Process in a Multi-stage Circulation Absorber

“…In the water wash section, the large aerosols were intercepted with decreasing number concentrations, while the small aerosols increased in number due to condensation. In addition, compared to other studies 10,12,17 where the aerosol median diameter was concentrated in the 0.1−1 μm range, the median aerosol size in this study was larger, implying that the capture was more easily achieved. The discrepancy could be explained by the larger amount of solvent and more adequate absorption reaction in the MSC absorber.…”

“…For instance, Khakharia et al found that the total emission of MEA ranged from 1200 to 1900 mg/m 3 at aerosol number concentrations of 1.4–1.7 × 10 8 1/cm 3 . In our previous research, the aerosol mass concentration reached 2341.3 mg/m 3 with a number concentration of 1.3 × 10 7 1/cm 3 . Moreover, aerosol emissions cannot be effectively reduced by conventional countermeasures such as a water wash or demister. , In general, aerosol emissions are usually produced by heterogeneous and homogeneous condensation.…”

“…Yi et al found that amine emissions changed from 240 to 2000 mg/m 3 at lean solvent temperatures of 303–323 K in an experimental CO 2 absorber with a simulated flue gas flow of 3.6 m 3 /h. Moreover, in our previous research, 100–700 mg/m 3 aerosol concentration was measured, with the solvent temperature changing from 313 to 333 K. Apart from the temperature, the CO 2 loading of the solvent and the partial pressure of CO 2 will affect the aerosol emissions by influencing the solvent volatility. The aerosols in the gas bubbling through the solvent were tested by Fujita et al , and only a few aerosols were found to be generated at a high solvent CO 2 loading or a low CO 2 concentration.…”

Hydrophobic Black Carbon Capture from Ship Emissions Based on a Charger-Coupled Wet Scrubber

“…Details of the experimental parameters are summarized in Table . It should be noted that the heat exchanger and wet electrostatic precipitator shown in Figure were utilized for amine and sulfuric acid aerosol removal, , and the heat exchanger remained inactive throughout the study to prevent potential interference with the precharging enhancement for black carbon scrubbing. The wet electrostatic precipitator (WESP) was periodically activated to mitigate the risk of fan clogging due to excessive accumulation of SP-BC in the pipelines.…”

Multistage Circulation Absorption Improvement: Simulation and Energy-Saving Evaluation of an Innovative Amine-Based CO2 Capture Process

“…In our previous work, 43 we have used a small-scale MSC experimental platform to investigate and evaluate the absorption performance and regeneration duty of the MSC process. 44 Simultaneously, the MSC process was modeled and studied by using Aspen Plus. As shown in Figure 3, the simulation results were all within the error bars of the experimental data, confirming the reliability of the model.…”