基于水泥修饰的赤铁矿载氧体污泥化学链燃烧特性研究
Chemical looping combustion of sewage sludge with oxygen carrier of cement-modified hematite
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摘要: 采用水泥修饰赤铁矿来提高载氧体的反应活性。实验在1kWth串行流化床上进行,研究了添加水泥对污泥化学链燃烧特性的影响,考察其长期运行的物化性能。结果表明,在实验工况下,赤铁矿添加水泥后,出口的未燃气体浓度明显下降。燃料反应器温度低于870℃时,水泥的添加使污泥的碳转化率和燃烧效率显著升高。在10h长期运行后,一部分污泥灰沉积在载氧体表面。虽然在反应过程中部分的Fe2O3被深度还原,但在长期运行中未出现流化问题和烧结现象。Abstract: Chemical looping combustion (CLC) for sewage sludge has a relatively low efficiency using hematite as oxygen carrier. The experiments on improving the reactivity of hematite with cement modified for CLC of sewage sludge in a 1kWth continuous CLC unit were carried out. Compared to hematite oxygen carrier, the concentrations of unconverted combustible gas rapidly decrease when the cement-hematite is used. Moreover, both carbon conversion and combustion efficiency increase when the cement is added. Although some ash particles deposit on the surface of oxygen carrier and a part of Fe2O3 is reduced to FeO, there are no defluidization and sintering problems.