摘要
实验研究了酸改性沸石在剩余污泥调理中的应用。采用单因素法,以比阻作为主要参数,分别从酸浓度、酸浸时间和沸石粒度等方面来确定沸石酸改性的最佳条件。最佳的改性沸石在酸浓度为3 mol/L,酸浸时间为5 h,沸石粒径为150μm的条件下获得。利用改性沸石来调理污泥,考察改性沸石投加后污泥沉降和脱水性能的变化以及对污泥上清液中COD、氨氮的去除效果。结果表明,沸石可以有效的调理污泥,减小污泥的比阻,且改性后的沸石调理效果更好。当改性沸石投量为30%(污泥含固量计)时,污泥的比阻由原来的3.0×1013m/kg降到1.39×1013m/kg,滤饼的含水率由原来的92%降到64%。沸石改性前后颗粒的电镜扫描图说明其强化污泥调理的机理主要是吸附架桥作用。
In this study, sludge conditioning was improved by sulfuric acid-modified zeolite. Based on single-factor experiments method with specific resistance to filtration （SRF） as the target index, the modified conditions such as acid concentration, acid leaching time, zeolite particle size were optimized. The optimal modified zeolite was obtained with acid concentration of 3 mol/L, the leaching time of 5 h and zeolite size of 150 μm. The effect of modified zeolite on the dewaterability and settleability of sludge and the removal of COD and NH3-N in the supernatant was investigated. The results showed that the SRF of the sludge significantly decreased with zeolite addition, and the modified zeolite had much stronger conditioning capacity than the raw zeolite. When the modified zeolite dosage was 30%, the SRF of the sludge decreased from 3.0×1013 m/kg to 1.39×1013m/kg, and the filter cake moisture decreased from 91% to 64%. The enhanced mechanism of sludge conditioning by acid-modified zeolite was attributed to the bridge adsorption according to SEM.
出处
《环境工程学报》
CAS
CSCD
北大核心
2013年第7期2678-2684,共7页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(51078128)
国家国际科技合作计划(2011DFA90740)
中央高校基本科研业务费专项资金
关键词
酸
机理
改性沸石
污泥调理
acid
mechanism
modified zeolite
sludge conditioning
