人工湿地基质吸附磷素性能及动力学研究

PERFORMANCES AND DYNAMICS OF SUBSTRATE IN CONSTRUCTED WETLAND SYSTEM ADSORBING PHOSPHORUS

以铁粉和湿地常用基质(河沙)为研究对象,研究两者对污水中磷素的等温吸附特征,并运用1级和准2级动力学模型分析其吸附磷素的动力学过程,考察其吸附磷素的规律和性能。结果表明,铁粉和河沙对溶液中磷素的等温吸附特征符合非线性Langmuir方程,吸附反应在常温下能自发进行,铁粉吸附磷素反应自发程度、对磷素的吸附能力以及生成物的稳定性都大大超过河沙。结合1级和准2级动力学模型标准偏差R2值、1级动力学模型参数w与Langmuir方程理论最大吸附量Q0的相对误差以及准2级动力学模型参数Qe与Q0的相对误差,铁粉对水溶液中磷素的吸附动力学过程更符合1级动力学模型,河沙对水溶液中磷素的吸附动力学过程更符合2级动力学模型。

Constructed wetland system （CWS）is an effective alternative to traditional technology ofphosphogus removal from wastewater. Iron and sands （normal substrate of WS） are closed as research objects, the isothermal adsorption characteristics of iron and sands adsorbing phosphorus in the wastewater are researched, dynamic process iron and sands adsorbing phosphorus in the are analyzed by first order reaction kinetic model and pseudo-second-order kinetics model, rule and performance of adsorbing phosphorus are investigated. Researches show that isothermal adsorption characteristics of both iron and sand adsorbing phosphorus conform to Langmuir equation, absorption reaction can be spontaneous, spontaneous degree, adsorption ability and stability of iron adsorbing phosphorus are better than sand. Adsorption kinetic of irol~ adsorbing phosphorus in the wastewater is closer to the first order reaction kinetic model, while sand is closer to the pseudo-second-order kinetics model by analyzing standard errors of first order reaction kinetic model and pseudo-second-order kinetics model, relative errors between parameter（Q0） of Langmuir equations and parameter（w） of first order reaction kinetic model and parameter （Qc） of pseudo-second-order kinetics model synthetically. Research results enrich and develop water pollution control and remediation theory of CWS and provide new ideas for constructing dynamic model of matrix adsorbing solute.