【作者】 汪涛；

【导师】 梁斌；

【作者基本信息】 四川大学 ， 工业催化， 2002， 硕士

【摘要】 大量从燃煤锅炉里排放出来的SO₂不仅对环境造成严重危害，还是硫资源的一种很大浪费，每年排入水气的SO₂近2370万吨。再生脱硫技术是有效控制大气污染，合理回收资源的重要手段。 作者制备了新型复合CaO-Fe₂O₃／γ-Al₂O₃负载型再生烟气脱硫剂。在600℃下对模拟烟气进行了脱硫研究，硫容达7.7％（wt），脱硫反应后可用CH₄再生直接回收单质S。所得脱硫剂有较好的脱硫再生性能，经4次脱硫再生循环，平均再生率达81.3％。 脱硫剂中引入Fe可以通过催化SO₂氧化反应而改变了CaO／γ-Al₂O₃脱硫剂脱除SO₂的反应历程。Fe与CaO之间存在一定的交互作用，大大提高了脱硫剂对SO₂的脱除性能。脱硫剂中的活性物质氧化钙和氧化铁在脱硫过程中同烟道气中的SO₂和氧气反应转变成硫酸钙和硫酸铁，还原再生时又转变成原有结构的氧化钙和氧化铁，获得再生。 对脱硫剂制备工艺进行了研究，浸渍溶液Ca（NO₃）₂的浓度与所得脱硫剂的CaO负载量呈线性关系，在一定的浓度范围内，CaO的负载量可以根据浸渍溶液浓度进行预测估算。Ca—Fe双组分脱硫剂中Ca、Fe含量的最适宜比例为3：1。Ca、Fe分步浸渍时SO₂去除率、脱硫速率以及脱硫硫容等指标均优于同时浸渍。最佳脱硫温度为600℃，脱硫后脱硫剂最大S／（Ca+Fe）原子比为0.7。更多还原

【Abstract】 A huge emission of SO2 from the chimneys of coal combustion boilers is not only a serious environmental problem, but also a great waste of sulfur resource. About 23,7 million tons of SO2 is emitted into atmosphere every year. Regenerative desulfurization process is an effective measure to control air pollution and recover sulfur resource.A novel complex alumina supported calcium oxide and ferric oxide adsorbent was prepared by step wet impregnation method. The desulfurization and regeneration behaviors of this adsorbent were tested at 600C. The results indicate that the sulfur capacity of the adsorbent reaches 7.7 wt%. The adsorbent can be regenerated with CH4, and sulfur is the only regeneration product. The activity maintains as high as 81.3% of the initial activity after four desulfurization-regeneration cycles.The mechanism of desulfurization reaction can be changed by introducing ferric oxide. The ferric oxide is a catalyst of SO2 oxidization. A strong interaction exits between calcium oxide and ferric oxide. The desulfurization behavior is greatly improved by introducing ion into adsorbent. The active components, calcium oxide and ferric oxide convert to calcium sulphate and ferric sulphate during desulfurization, then the sulfates are reduced to obtain calcium oxide and ferric oxide in regeneration.The preparation of the adsorbent was researched. The calcium oxide loading of adsorbent is proportional to the concentration of calcium nitrate in impregnation solution. So the calcium oxide loading can be estimated according to the concentration of impregnation solution within a given concentration range. The optimal ratio of active components Ca to Fe in complex adsorbent is 3:1. The desulfurization rate and sulfur capacity of the adsorbents prepared by step impregnation method are high than those of the adsorbents prepared by mixed impregnation. The optimal temperature of desulfurization is 600 C. At this temperature, the maximal ratio of S/(Ca+Fe) is 0.7 after desulfurization.更多还原