哈尔滨城市污水处理厂不同处理工艺对微塑料的去除

城市污水处理厂出水作为微塑料(microplastics,MPs)进入自然水体的主要途径之一,对其微塑料污染物特征展开研究,有助于认识和了解人类活动对自然水体的影响.本文以哈尔滨市主城区的污水处理厂A和污水处理厂B中的3种工艺(曝气生物滤池工艺、多段AO-MBBR工艺、CASS-MBBR工艺)为研究对象,经体视显微镜观察并结合傅里叶变换红外光谱仪分析哈尔滨城市污水处理厂中MPs的浓度、颜色、粒径、类型分布特征及3种不同处理工艺对MPs的去除效果.结果表明,哈尔滨城市污水处理厂进水中MPs的最高浓度为290.87个·L^-1,颜色主要以白色和无色为主,组成成分主要为PP、PE和PS,粒径大的MPs更容易被去除;微塑料在曝气生物滤池工艺一级处理中的去除率为80.28%;多段AO-MBBR工艺与CASS-MBBR工艺的一级处理MP_S去除效率为78.39%,曝气生物滤池工艺、多段AO-MBBR工艺和CASS-MBBR工艺的二级处理去除效率分别为20.92%、13.11%和14.68%,实验结果表明MPs的去除主要依靠一级处理,二级处理中的MPs去除效果...

Removal of microplastics in different wastewater treatment processes in Harbin municipal wastewater treatment plants

The effluent of municipal wastewater treatment plant is one of the main ways for microplastics (MPs) to enter natural water environment. The study of the characteristics of microplastics pollutants will help people to understand the impact of human activities on natural water environment. Three wastewater treatment processes in two municipal wastewater treatment plants A and B in Harbin are the research objects of this paper. The three processes are Biological Aerated Filter process, multi-stage AO-MBBR process, CASS-MBBR process). The concentration, color, particle size, distribution of MP_S and the removal effect of three different treatment processes on MP_S were analyzed by stereo microscope combined with Fourier transform infrared spectrometer. The results show that the highest concentration of MPs in the influent of Harbin municipal wastewater treatment plant is 290.87 particles·L^-1, the influent is mainly white and colorless, and the main components are PP, PE and PS, in the meantime MPs with larger particle size is easier to be removed. the removal efficiency of microplastics in the primary treatment of Biological Aerated Filter process was 80.28%. The MPs removal efficiency of multi-stage AO-MBBR process and CASS-MBBR process was 78.39%. The removal efficiency of secondary treatment of Biological Aerated Filter, multi-stage AO-MBBR and CASS-MBBR were 20.92%, 13.11% and 14.68% individually. The experimental results show that the removal of MPs mainly depends on the primary treatment, and the removal of MPs in the secondary treatment is less effective. The conclusion can provide scientific basis for the study of microplastics pollution prevention and control in municipal wastewater treatment plant.