Is fly ash boosting amine losses in carbon capture from coal?

摘要

Fly ash entering a CO2 capture plant in the incoming coal-fired flue gas is a potential source of metals that may boost amine losses in the plant. This study presents a comparative assessment of the impact of fly ash quality and the level of solvent degradation on the leaching mobility of ash metals. The results of two ash samples from two European power stations are presented leached with fresh 30 wt% lean MEA & degraded lean MEA solvent taken from the capture pilot plants based at these to power stations. The results show that degradation of the solvent increases the mobility for Mn & V (and by extrapolation Cu and other trace metals), but Fe mobility remains unchanged with increased degradation, Ash/solvent ratio was found to have the most significant impact on leaching rates and with lower ratios expected in the process than tested here, it is expected that fly ash leaching will only be a minor contribute to total metal levels in the solvent and subsequent catalyzed degradation. It is recommended to conduct further studies using lower ash/solvent ratios and to consider the impact of FGD carryover on the metal transfer into the solvent.