粉煤灰合成沸石同步脱氨除磷特性的研究  

Study on Characteristics of Simultaneous Removal of Ammonium and Phosphate from Waste Water by Zeolitized Fly Ash

作　　者：赵统刚[1] 吴德意[1] 陈建刚[1] 孔海南[1] 张葆华[1] 王灶生[1] 

机构地区：[1]上海交通大学环境科学与工程学院,上海200240

出　　处：《环境科学》2006年第4期696-700,共5页Environmental Science

基　　金：国家高技术研究发展计划(863)项目(2002AA601013);上海市重大科技攻关项目(04DZ12030-2)

摘　　要：利用粉煤灰合成沸石，研究其在同步去除氮、磷方面的特性．合成沸石对氨氮和磷酸盐的吸附净化均随时间增加而变化，但均在24h后基本达到平衡．随合成沸石投加量的增加，同步去除污水中氮磷的效果越好，但在投加量为8g·L^-1以上时去除率的增加明显放慢．在pH为7～9时氨氮去除率最高（约60％），超过此pH范围时去除率降低．在pH7～9范围磷去除率达最低（约为85％），超过此pH范围时去除率增加（最高达到近100％）．合成沸石对氨氮的吸附为放热反应，对磷的吸附为吸热反应．不同阳离子饱和的合成沸石对氨氮的吸附顺序依次为：Al〉Mg〉Ca〉Na〉Fe，对磷的吸附顺序则为：Al〉Fe〉Ca〉Mg〉Na．合成沸石的氨氮吸附机理为阳离子交换作用，对磷的去除除化学沉淀作用外尚有吸附机制．Characteristics of simultaneous removal of ammonium and phosphate from wastewater by zeolite synthesized from fly ash was investigated. The amount of ammonium and phosphate removed by zeolitized fly ash changed with time, and approached to a constant value after adsorption time of 24h was reached. The amount of ammonium and phosphate removed also increased with the rise in the amount of zeolite added, but slackened above the solid/liquid ratio of 8 g· L^- 1. The removal rate of ammonium by zeolitized fly ash could rise to the maximum value of 60% when pH was between 7 and 9, and declined out of the pH range. For phosphate, minimum removal rate of about 85% was obtained within pH 7-9, and the removal rate increased to about 100% out of the pH range. The adsorption of ammonium on zeolitized fly ash was an exothermie reaction; the removal rate of ammonium could decrease with the rise in temperature. On the contrary, the adsorption of phosphate was an endothermie reaction, and the rise in temperature favored the removal of phosphate by zeolitized fly ash. The adsorptive ability of ammonium on zeolitized fly ash was： Al-Z〉Mg-Z〉Ca-Z〉Na-Z 〉 Fe-Z. The order for phosphate was： Al-Z 〉 Fe-Z 〉 Ca-Z 〉 Mg-Z 〉 Na-Z. It was proposed that the mechanism for the removal of ammonium from wastewater by zeolitized fly ash was cation exchange process, while the mechanism for phosphate was not only the precipitation reaction of phosphate with cation in solution, but also adsorption mechanism.

关 键 词：合成沸石 粉煤灰 氨氮 磷酸盐 去除 特性 

分 类 号：X703.1[环境科学与工程—环境工程] X705