微塑料(MPs)在水生系统中的威胁几乎是环境管理中的新挑战。市政污水处理厂(WWTP)既是人为使用的MP的收集者,也是自然环境的来源。这项研究的目的是确定丰度,特点,并通过常规活性污泥法去除市政污水处理厂中的MP。粒度/类型,进水负荷,和条形屏幕中MP的去除率,沉砂池,初级沉降,返回的活性污泥,通过在3个月的采样活动中从废水和污泥中收集复合样品,研究了该污水处理厂的二级澄清单元。通过光学显微镜对疑似MP颗粒进行计数,并使用SEM进行表征,EDS,FTIR,和TGA-DSC技术。议员总数的平均值,纤维,沉砂池后的碎片浓度为6608、3594和3014,分别减少到流出物中的1855、802和1053颗粒/L,分别。总MP的污泥保留率,纤维,碎片为8001、3277和4719个颗粒/L,分别。污水处理厂采用活性污泥法去除MPs的总效率为64%,去除纤维和碎片的总效率为66.6%和60%,分别。纤维是沉砂池后收集的样品的主要形状,并且碎片在流出物中普遍存在。在大多数废水样品中检测到聚乙烯聚合物。现有的处理工艺可有效去除MP颗粒,但仍可作为水生生态系统的潜在来源。
The threat of microplastics (MPs) in aquatic systems is almost a new challenge in environmental management. The municipal wastewater treatment plants (WWTPs) act both as collectors of MPs from anthropic use and as a source to natural environments. This study is aimed to determine the abundance, characteristics, and removal of MPs in a municipal WWTP with conventional activated sludge process. Particle size/type, influent loads, and removal rate of MPs in bar screen, grit chamber, primary sedimentation, returned activated sludge, and secondary clarification units of this WWTP were studied by collecting composite samples from wastewater and sludge over a 3-month sampling campaign. Suspected MP particles were counted by light microscopy and characterized using SEM, EDS, FTIR, and TGA-DSC techniques. The mean total MPs, fibers, and
fragment concentration after the grit chamber were 6608, 3594, and 3014 which were reduced to 1855, 802, and 1053 particles/L in the effluent, respectively. The sludge retention of total MPs, fibers, and fragments were 8001, 3277, and 4719 particles/L, respectively. The overall efficiency of WWTP with an activated sludge process to remove MPs was 64% and it removed 66.6% and 60% of fibers and fragments, respectively. Fibers were the dominant shape for the collected samples after the grit chamber and fragments were prevalent in the effluent. Polyethylene polymer was detected in most wastewater samples. Existing treatment processes are effective in the removal of MP particles but still act as a potential source to the aquatic ecosystem.