吸附法处理污水厂尾水的性能以及再生利用简析

The effect and characteristics of tailwater recycling of sewage treatment plant by adsorption method

水资源是制约经济发展的重要因素,再生水循环利用是解决这一问题的主要途径,再生水用于景观用水时,氨氮、总磷、总氮及化学需氧量指标常常成为限制因素。以某生活污水厂二沉池出水为处理对象,研究了活性炭投加量、吸附时间、初始pH和温度对吸附效率的影响,分别采用拟一级动力学方程和拟二级动力学方程对NH_(4)^(+)-N、TP、TN和COD吸附实验的动力学进行研究,通过采用三维荧光光谱法及荧光区域积分分析(FRI)对二沉池出水进行定量分析,考察活性炭吸附效果。结果表明:在温度25℃,活性炭投加量1.5 g/L,吸附时间80 min,pH=7条件下,NH_(4)^(+)-N、TP、TN和COD去除率分别为98.01%、94.04%、32.40%和82.14%,处理效果良好,技术经济可行,满足再生水景观回用标准。动力学研究表明,Langergren准二级动力学方程能较好地反映出活性炭吸附NH_(4)^(+)-N、TP、TN和COD的动力学过程,吸附存在化学吸附。三维荧光光谱法研究表明,活性炭吸附对二沉池出水中有机物具有较好的降解作用。

Water resource is an important factor restricting economic development,and reclaimed water recycling is the main way to solve this problem.Ammonia nitrogen,total phosphorus,total nitrogen and chemical oxygen demand indicators often become limiting factors for reclaimed water used for landscape.Taking the effluent of the second sedimentation tank of a domestic sewage plant as the treatment object,the effects of activated carbon dosage,adsorption time,initial pH value and temperature on the adsorption efficiency were studied,and the kinetics of NH_(4)^(+)-N,TP,TN and COD adsorption experiments were studied by quasi-firstorder kinetic equations and quasi-second-order kinetic equations.The effluent of the secondary sedimentation tank was quantitatively analyzed by three-dimensional fluorescence spectroscopy and fluorescence region integral analysis(FRI)to investigate the adsorption effect of activated carbon.The results showed that the removal rates of NH_(4)^(+)-N,TP,TN and COD were 98.01%,94.04%,32.40%and 82.14%,respectively,at a temperature of 25°C,the dosage of activated carbon of 1.5 g/L,the adsorption time of 80 min,and the pH=7.It met the standards of reclaimed water landscape reuse,indicating a good treatment effect,technical and economic feasibility.Kinetic studies showed that the quasi-secondary kinetic equation of Langergren can better reflect the kinetic process of activated carbon adsorption of NH_(4)^(+)-N,TP,TN and COD,and the adsorption is chemically adsorbed.The three-dimensional fluorescence spectroscopy study showed that the adsorption of activated carbon had a good degradation effect on the organic matter in the effluent of the second sedimentation tank.