摘要：以磷石膏(PG)为活性组分,膨润土(Ben)为惰性载体,用机械混合法制备PG-Ben载氧体,为了提高其反应活性,用机械混合-浸渍法分别制备Fe₂O₃、CuO、NiO修饰PG-Ben的Fe-PG-Ben、Cu-PG-Ben、Ni-PG-Ben载氧体;利用X射线衍射、N2吸附-脱附等手段对其进行表征,并在流化床反应器中考察其煤化学链燃烧反应性能。结果表明:PG-Ben载氧体浸渍Ni、Cu、Fe后载氧体的反应活性显著提高,且NiPG-Ben载氧体性能最好,Ni-PG-Ben载氧体的反应性能随着Ni浸渍量的增加而提高;12次循环以内,CO₂干基体积分数保持在80%以上,Ni-PG-Ben载氧体对应的碳转化速率由第1次的0.114 min^-1减小到第15次的0.077 min^-1;Ni-PG-Ben载氧体反应活性降低由生成不具备催化作用的CaNiSi₄O₁₀以及载氧体表面具有煤催化气化作用的Ni元素流失所致。

关键词：煤； 磷石膏；化学链燃烧；载氧体；流化床

Abstract：Through mechanical-mixing method, the oxygen carriers were prepared with phosphor gypsum(PG) as an active component and bentonite(Ben) as an inert support. In order to improve their reactivity, PG-Ben oxygen carriers decorated with Ni,Cu,Fe were prepared by mechanical mixing-impregnation method. The physical and chemical properties of these oxygen carriers were characterized by X ray diffraction and N₂ absorption-desorption measurements. The reactivity of these oxygen carriers in coal chemical looping combustion was performed in a fluidized bed reactor. The results show that the reactivity of the decorated oxygen carriers is improved as its surface area increases and Ni-PG-Ben oxygen carriers exhibit better performance than the others. The reactivity of NiPG-Ben oxygen carriers is enhanced by the increase of impregnation increment. The volume fraction of CO₂ is above 80% in 12 cycles. The carbon conversion rate decreases from 0.114 min^-1 in the first redox test to 0.077 min^-1 in the fifteenth redox test. The performance of Ni-PG-Ben oxygen carrier decreases because of the generated CaNiSi₄O₁₀ which does not have catalysis effect and the loss of Ni which can catalyze the process of coal gasification.

Keywords: coal； phosphor gypsum；chemical-looping combustion；oxygen carrier；fluidized bed