节点文献
浆液中飞灰对湿法脱硫过程化学的影响
Effect of Fly Ash in Slurry on Chemical Properties of Wet Desulfurization Process
【摘要】 基于湿法脱硫中试台,开展湿法脱硫塔内含灰浆液对系统过程化学影响。试验表明:石膏、飞灰的当量脱硫能力仅相当于新鲜脱硫剂的0.4、1%。吸收塔内浆液飞灰浓度为0%、1.5%、3.0%、6.0%时,飞灰对系统脱硫效率均具有一定的促进作用,且pH值越低,效应越明显。与空白工况相比,pH值为5.6~6.0,效率增幅分别为0.37%、0.55%、0.75%;pH值为5.0~5.5,对应增幅为0.75%、0.91%、1.23%。系统脱硫时间有随着浆液中飞灰含量增加而逐渐缩短的趋势,pH值降至5.4时,系统脱硫持续时间分别为156、148、130、100 min。低pH值下飞灰溶解浸出大量的Fe3+、Mn2+,石膏浆液催化氧化性能加强,SO32-浓度显著越低。总体而言,浆液中SO32-含量与浆液pH值呈正向相关,而与浆液中飞灰含量负向相关。
【Abstract】 Based on the pilot plant of limestone-gypsum wet flue gas desulfurization,the efficiency of desulfurization,acidification and desulfurization reaction,consumption of limestone,CaCO3in gypsum and oxidation of SO32-with different mass concentration of fly ash in slurry were studied.Results showed that the equivalent desulfurization capacity of gypsum and fly ash is only 0.4%and 1%of that of fresh desulfurizer.When the fly ash concentration is 0%,1.5%,3.0%and 6.0%,the fly ash in slurry can promote the efficiency of desulfurization.Compared with the blank condition,the efficiency increases are 0.75%,0.91%,and 1.23%with the pH value of 5.6~6.0 and 0.37%,0.55%and 0.75%while the pH value is 5.0~5.5,respectively.After adding fly ash,the desulfurization reaction time of the slurry was shortened with different p H values.The higher the pH value,the more obvious the effect.SO32-content in gypsum slurry is positively correlated with pH value,but negatively correlated with fly ash content in slurry.The lower the pH value,the higher the precipitation of Mn2+,Fe3+,the stronger the catalytic oxidation ability,and the lower the concentration of SO32-in the slurry.
【Key words】 fly ash; wet flue gas desulfurization; gypsum quality; oxidation of sulfite; efficiency of desulfurization;
- 【文献出处】 环境科学与技术 ,Environmental Science & Technology , 编辑部邮箱 ,2019年S1期
- 【分类号】X773
- 【被引频次】1
- 【下载频次】54