人工钙基脱硫剂活性和温度特性的研究

脱硫剂的活性和温度特性是影响沸腾炉煤燃烧脱硫效率的两个重要因素。实验表明,以石灰石为有效成分的人工钙基脱硫剂的反应活性是石灰石的2—3倍,且在800℃—1100℃较宽的温度范围内保持这一水平.本文以石灰石和两种人工脱硫剂试样(含固硫渣和不含固硫渣)为研究对象,应用管式反应炉、扫描电子显微镜和压汞仪等对样品进行了一系列宏观与微观的对比实验,探讨了人工脱硫剂的活性和温度特性.结果表明,在人工脱硫剂成型过程中人为形成的大孔分布改善了反应气体的扩散,从而提高了它的反应活性。而且大孔和固硫渣的共同作用还削弱了晶粒膨胀和烧结的不利影响,从而使其最佳脱硫温度较石灰石向高温区移动了近200℃.此外本文还讨论了最佳温度的相对性。

Study on the Reactivity and Temperature-Characteristic of Colcium-Based Sulfur Sorbent

The reactivity and temperature-characteristic of sor-bent are two criticial factors affecting sulfur-capture efficiency in the process of fluidized bed combustion of coal. The synthetic sorbent developed by the authors, although mainly consisting of limestone fines, possesses higher reactivity than the limestone itself and could be used in a wider range of temperature up to 1100C. In order to study the phenomenon, experiments were conducted by using a fixed bed reactor, a mercury porosimeter and a scanning electrinic micro-scope etc. Two kinds of synthetic sorbents (with and without sulfur-retentive ash) and limestone were used in the study. Results demonstrate that large pores in the synthetic sorbents, wich were formed in the process of agglomeration, enhanced the diffusion of SO2 and O2 and, therefore, led to the high reactivity of the sorbent. In the meantime, sulfur-retentive ash deferred the ocurrance of sintering and thus made the optimum temperature shift to a high level.