钙基载氧体煤化学链燃烧脱硫试验研究

在钙基载氧体燃煤化学链燃烧技术过程中由于煤气化产物与载氧体之间的副反应导致反应过程中产生大量的SO₂气体。本文选择MAC铁矿石,CaO和石灰石作为脱硫剂,在小型加压固定床上研究不同温度、压力、Ca/S比条件下SO₂气体的脱除问题。结果表明,单独采用CaSO₄载氧体时,随温度升高SO₂气体浓度逐渐增加。添加铁矿石后,SO₂排放浓度降低,主要与Fe₂O₃能够催化抑制CaSO₄分解有关。添加CaO和石灰石脱硫剂后,随温度、压力以及Ca/S比增加,两种脱硫剂的脱硫效率均增加,且在相同的实验条件下得到的CaO的脱硫效果更佳。

Experimental Study of Desulfurization of Chemical-Loping Combustion of Coal With Calcium-based Oxygen Carrier

In the process of chemical-looping combustion of coal with calcium-based oxygen carrier, large amount of SO₂ was released due to the side reactions occurred between CaSO₄ oxygen carrier and coal gasification products.In this work,desulfurization experiments were conducted using MAC iron ore,CaO and limestone as desulfurizers in a laboratory scale pressurized fixed-bed reactor.The influencing factors of temperature,pressure and Ca/S ratio on the removal of SO₂ gas were analyzed. The results showed that the outlet concentration of SO₂ increased with the increase of temperature in the presence of only CaSO₄ oxygen carrier.Adding MAC iron ore into the reactor could reduce the concentration of SO₂ released from the reactor due to the catalytic effect of Fe₂O₃ on suppressing the decomposition of CaSO₄.The desulfurization efficiency of both CaO and limestone showed an increased trend with the increase of temperature,pressure and Ca/S ratio,and CaO showed a better performance than limestone under the same experimental conditions.