关键词:

氧化铁, 活化中心, 石灰, 中温烟气脱硫

Abstract: The FGD process of mixture of lime and Fe₂O₃ is analyzed by using TGA in this paper.It is shown that Fe₂O₃ can’t react with SO₂ from 200℃ to 700℃.The desulfurization efficiency of lime is improved with temperature rising.SO₂ can be captured by lime at 600℃ or 700℃. But there is almost no desulfurization reaction taking place with lime when temperature is below 500 ℃. The behavior of lime in desulfurization reaction does not change with added Fe₂O₃. But the conversion rate of CaO is greatly improved:the more Fe₂O₃, the higher the conversion rate.Fe₂O₃ acts as an activator more than a catalyst in the desulfurization reaction with lime.Fe₂O₃ acts as the “activation center”around which CaO particles are sulfurized.The new dispersal formation mode of product differs from the compact layer that used to be. And the pore structure of product layer on the surface of lime particles is optimized, which makes SO₂ penetrate into core parts of lime more easily. As a result, the desulfurization reaction is developed deeper into the core parts of absorbent.

Key words:

氧化铁, 活化中心, 石灰, 中温烟气脱硫