飞灰/石灰吸着剂制备及其脱硫脱硝性能的研究

Performance of Fly Ash/Lime Sorbents for Simultaneous Removing SO_2 and NO_X from Flue Gas

以飞灰和石灰为原料,采用常压水合、蒸汽水合、加压水合三种水合方式制备干法脱硫脱硝吸着剂,并探讨了吸着剂表面及孔结构特性对脱硫脱硝性能的影响。研究了制备条件如:飞灰/石灰比、水合温度、压力等因素对吸着剂表面及孔结构特性及其脱硫脱硝性能的影响。结果表明,以飞灰和石灰水合制得的吸着剂的比表面积和孔体积均远大于原料石灰或飞灰的比表面积和孔体积。水合制得的飞灰/石灰吸着剂比表面积最大可达97.55m2/g,孔隙体积更是较两种原料增大了10～100倍;水合法制备飞灰/石灰吸着剂时,飞灰/石灰比对吸着剂的表面及孔结构特性影响最大,在飞灰/石灰比为1/1时,制得的吸着剂的脱硫脱硝性能较优;水合制备的飞灰/石灰吸着剂,比表面积40m2/g以上,且孔径在250～270A觷时,表现出具有较高的脱硫脱硝活性。

Sorbents were prepared with fly ash and lime in hydration, with discussion of characteristics in specific surface and pore structure of sorbents and their performance in desulfurization and denitrification. Conditions of hydration such as ratio of fly ash to lime, hydration time and hydration pressure were investigated, results showed that specific surface area and pore volume of sorbents were much larger than that of fly ash or lime as materials. Specific surface area of sorbents was close to 97.55m^2/g at the most, and pore volume increased 10-100 times. Ratio of fly ash and lime had important influence with attribute of macro structure. Results showed that when ratio of fly ash and lime was 1 to 1 or the specific area was larger than 40m^2/g, median pore diameter was about 250-270A, the sorbents had better effect of desulfurization and denitrification.