【作者】 张颖；

【导师】 袁宏林；

【作者基本信息】 西安建筑科技大学 ， 建筑与土木工程， 2018， 硕士

【摘要】 城市面源污染对于地表水环境的污染越来越受到关注,尤其初期雨水径流中含有众多有机污染物和重金属污染物,对于河道水体水质的影响甚大,有效收集、净化、处理、利用初期雨水对水环境污染防治有着重要意义。人工快速渗滤系统（CRI）应用于初期雨水径流处理的相关研究较少。本文依托“十二五”宜兴水专项“城区水污染控制和水环境功能提升技术研究”展开,重点研究了沸石和石灰石对雨水中常见低浓度铅、铜、锌、镉四种重金属离子共同存在时的去除规律,再考虑到兼顾去除初期雨水径流中COD、总氮、总磷、氨氮等有机物,在沸石和石灰石做填料的情况下又加入河砂、粉煤灰、钢渣、木糠等新型填料,探究CRI系统对于处理初期雨水径流的可行性和有效性。本文的主要实验结果如下:（1）沸石和石灰石对四种低浓度离子共存的吸附实验表明两种吸附剂去除重金属离子,在一定范围内,吸附剂投加量越大,重金属去除效果越好;实验中吸附剂增加到0.5 g后,所有重金属的去除效果变化不再明显。对于沸石和石灰石,重金属的去除率随接触时间增加而增加,当时间增加到300 min后,去除率均变化不再明显。温度对石灰石和沸石去除重金属影响并不完全相同,不同重金属离子受温度变化影响也不尽相同。重金属初始浓度对沸石和石灰石去除重金属的影响不同,不同重金属离子受浓度变化影响也不同。（2）Langmuir和Freundlich方程都能描述沸石和石灰石对4种重金属离子的等温吸附曲线,针对不同离子拟合效果不尽相同。零级方程、准一级动力学方程和准二级动力学方程对不同重金属吸附过程的拟合效果不同,其中零级方程对吸附过程的拟合效果不佳,准一级动力学和准二级动力学方程对不同重金属吸附过程的拟合效果均较好。(3沸石对四种重金属元素的竞争吸附体系下,各离子的竞争吸附能力强弱为Pb²⁺>Zn²⁺>Cd²⁺>Cu²⁺。石灰石对四种重金属元素的竞争吸附体系下,各离子的竞争吸附能力强弱为Cd²⁺>Zn²⁺>Cu²⁺>Pb²⁺。脱附实验表明,NaCl对沸石具有很好的脱附作用,四种重金属离子的脱附量几乎与钠离子的浓度成正比。（4）对人工快速渗滤系统填料进行优化,用于处理初期雨水径流中的重金属和有机物。实验分析可知,CRI系统对重金属的去除再生能力表现了很好的结果,系统稳定时对于Pb²⁺、Cu²⁺、Zn²⁺、Cd²⁺的平均去除率分别为83.05%、79.02%、68.69%、95.74%。本文所采用的CRI系统对有机物也具有很好的去除性能,系统稳定时对于COD、TN、TP、氨氮的平均去除率分别为86.60%、84.38%、71.95%、75.00%。更多还原

【Abstract】 Urban non-point source pollution on the surface water environment has attracted more and more attention.In particular,early rain runoff contains numerous organic pollutants and heavy metal pollutants.It has a great impact on the water quality of the river water.It has great significance of collecting,purifing,treating and using early rain runoff for prevention.Artificial rapid infiltration system（CRI）has rarely been applied to the early rain runoff treatment.This paper is based on the"twelfth Five-Year Plan"Yixing Water subject of"urban water pollution control and water environment function improvement technology research".The removal rules of zeolite and limestone for four common low concentrations co-existed ions lead,copper,zinc and cadmium was researched.Taking organic matter such as COD,TN,TP and NH₄⁺-N into account to remove,in the case of zeolite and limestone as fillers,new types of fillers such as river sand,fly ash,steel slag,and wood are added to the CRI system to explore the feasibility and effectiveness of the CRI system in handling early rain runoff.The main contents of this paper are as follows:（1）The adsorption experiments of zeolites and limestones for the removal of Pb²⁺,Cu²⁺,Zn²⁺and Cd²⁺,typical heavy metal ions in rainwater,shows that within a certain range,the greater the amount of adsorbent added,the better removal effect of heavy metals;When the adsorbent is increased to 0.5 g,the removal effect of heavy metals does not change significantly.For zeolites and limestones,the removal rate of heavy metals increases with the increase of contact time.When the time increases to 300 min,the removal rate change is no longer obvious.The effect of temperature on the removal of heavy metals for limestone and zeolites is not completely the same and the affection varies of different heavy metal ions.The initial concentration of heavy metals has different effects on the removal of heavy metals by zeolites and limestones,and different heavy metal ions are also affected by concentration changes differently.（2）Langmuir and Freundlich equations both can describe the isothermal adsorption curves of zeolite and limestone on the four heavy metal ions.The fitting effect is different for different ions.The zero-order equation,the pseudo-first-order kinetic equation and the pseudo-second-order kinetic equation have different fitting effects for different heavy metal adsorption processes.The zero-order equation has a poor fitting effect on the adsorption process.Quasi-first-order kinetics and quasi-two The kinetic equations have good fitting effects on the adsorption process of different heavy metals.（3）Under the competitive adsorption system of zeolites to four heavy metal elements,the competitive adsorption capacity of each ion is Pb²⁺>Zn²⁺>Cd²⁺>Cu²⁺.Under the competitive adsorption system of limestone to four heavy metal elements,the competitive adsorption capacity of each ion is Cd²⁺>Zn²⁺>Cu²⁺>Pb²⁺.The desorption experiments show that NaCl has a good desorption effect on zeolites,and desorption of four heavy metal ions is almost proportional to the concentration of sodium ions.（4）Optimize the filling of the artificial rapid infiltration system to treat heavy metal and organic matter in the early rain runoff.The experimental analysis shows that the CRI system shows good results for the adsorption and regeneration of heavy metals.The average removal rates of Pb²⁺,Cu²⁺,Zn²⁺,and Cd²⁺were 83.05%,79.02%,68.69%,and 95.74%,respectively,when the system was stable.The CRI system used in this paper also has good removal performance for organic matter.The average removal rates of COD,TN,TP,and ammonia nitrogen were 86.60%,84.38%,71.95%,and 75.00%,respectively,when the system was stable.Especially,the addition of wood hoe to the lower filler makes the system have a better removal effect on TN.更多还原