污水处理厂不同单元工艺水中重金属及其纳米颗粒的分布

以成都双流国际机场污水处理厂中连续处理废水工艺中的9个不同处理单元工艺为研究对象，通过电感耦合等离子体质谱法（ICP-MS）和单颗粒电感耦合等离子体质谱法（SP-ICP-MS）分别对污水处理厂中不同处理单元工艺中的重金属总质量浓度以及重金属纳米颗粒的数量浓度和粒径分布进行了分析，并研究了不同处理单元工艺对重金属元素及重金属纳米颗粒的去除效果.结果表明，不同处理单元工艺对不同重金属元素的去除效果存在差异，对Fe元素的影响最为显著，主要在二沉池中被去除，去除率达98.53%；不同处理单元工艺对不同重金属纳米颗粒的去除效果存在显著差异，对Ni、Pd和Fe纳米颗粒的影响最为显著，不同重金属纳米颗粒在不同处理单元工艺（曝气沉砂池、二沉池和高效沉淀池）中被去除；重金属纳米颗粒在不同处理单元工艺中的粒径分布为23.28~147.83 nm，不同处理单元工艺不会对各重金属纳米颗粒的粒径造成显著影响；pH与Fe元素和Fe纳米颗粒呈显著负相关关系，除Fe元素和Fe纳米颗粒外，其他重金属元素与其纳米颗粒之间均属于不显著相关，不同处理单元工艺对重金属元素和重金属纳米颗粒的去除机制存在差异.

Distribution of Heavy Metals and Their Corresponding Nanoparticles in Different Treatment Unit Processes in the Sewage Treatment Plant

Total heavy metal concentration, heavy metal nanoparticle concentration, particle size, and the removal effect of different treatment unit processes on heavy metals and heavy metal nanoparticles were analyzed in this study. Inductively coupled plasma mass spectrometry (ICP-MS) and single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) were applied in nine treatment units performing continuous wastewater treatment processes in the Chengdu Shuangliu International Airport sewage treatment plant. Results showed that different treatment unit processes had different effects on the removal of different total heavy metal elements, with the effects on Fe being the most significant; Fe was mainly removed in the secondary sedimentation tank at a rate of 98.53%. The removal effects of different heavy metal nanoparticles varied in different treatment unit processes, with the effects of Ni, Pd, and Fe being the most significant. Heavy metal nanoparticles removal varied by treatment unit processes (aeration grit tank, secondary sedimentation tank, and high-efficiency sedimentation tank). The particle size distribution of heavy metal nanoparticles in different treatment unit processes was 23.28-147.83 nm, and different treatment unit processes did not have a significant impact on the particle size of each heavy metal nanoparticle. In addition, pH exhibited a significant negative correlation with Fe and Fe nanoparticles. Excluding Fe and Fe nanoparticles, other heavy metals and their nanoparticles were not significantly related; thus, different processing unit processes exhibited different removal mechanisms for heavy metals and their corresponding nanoparticles.