Experimental and mechanism research of SO_2 removal by cast iron scraps in a magnetically fixed bed

摘要

Sulfur dioxide can be effectively removed by cast iron scraps corrosion process in a DC magnetically fixed bed, and iron sulfate compounds are gained as an available byproduct. At approximate 50 ℃, when magnetic field intensity was at 15 mT and height of scraps was about 25 mm, the SO_2 removal efficiency can be kept above 80%. As the deposited rusts accumulated, the corrosion rate and desulfurization efficiency gradually decreased. The results show SO_2 removal efficiency depends on corrosion rate, and it can be obviously enhanced by DC magnetic field. With the XRD and SEM research, it can be found that DC magnetic field cannot change the crystal structure of rusts, but can make the surface morphologies on the surface of scraps looser which means easily to be removed. Consequently, the corrosion resistance can be lessened and SO_2 removal efficiency is improved significantly.