活性矿浆湿法脱硫技术工程应用研究

Research and engineering application of wet desulfurization technology with active ore slurry

以活性矿浆为烟气脱硫剂,采用湿法脱硫技术,对冶炼过程产生的低浓度SO_2烟气进行脱硫工程化应用研究。由结果可知:活性矿浆平均硫容可达到3.78 kg/m^3,当入口烟气量在80 000—100 000 m^3/h,SO_2质量浓度在3 000—5 000 mg/m^3时,液汽比控制在6—9 L/m^3,平均脱硫效率能够达到94%,最高可达到99%,随着吸收时间的增加,活性矿浆pH值逐渐降低,当pH值在7.0—7.5时,循环液形成缓冲体系,吸收过程达到动态平衡,pH值下降趋势减缓,此时尾气能够稳定达标;当pH值<7.0时,pH值急剧下降,此时尾气会存在超标现象。此外,由于活性矿浆高含固、易沉降的特性,在工程化应用中塔型结构选用空塔,并在塔底设置相应的防沉降装置。

The engineering application of wet desulfurization technology of the low concentration SO2 smelting flue gas was researched with active ore slurry as desulfurizer. The results indicate that the average sulfur capacity of the active ore slurry can reach 3.78 kg/m3 and the average desulfurization efficiency can reach 94% and the maximum is 99% when the inlet flue gas amount is 80 000-100 000 ma/h and the SO2 mass concentration is 3 000-5 000 mg/m3 and the liquid-gas ratio is controlled in the range of 6-9 L/m3. Along with the increasing of the absorption time, the pH value decreases gradually. When the pH value is in the range of 7.0-7.5, the circulating fluid becomes buffer system and the absorption process achieves to the dynamic balance and the downward tendency of the pH value is slow, which can guarantee the offgas emission standard. When the pH value is under 7.0, it decreases dramatically and the exhaust overstandard phenomenon exists. Because of the speciality of high solid content and easy sedimentation of the active ore slurry, the hollow tower structure was applicated on the engineering and the precipitation device was set on the bottom of the tower.