MWH Americas Inc., 618 Michillinda Avenue, Suite 200, Arcadia, CA 91007, United States.
Water Res. 2010 Apr;44(8):2431-40. doi: 10.1016/j.watres.2010.01.003. Epub 2010 Jan 14.
A pilot study was conducted over a period of 18 months at the Point Loma Wastewater Treatment Plant (PLWWTP) in San Diego, CA to evaluate the operational and water quality performance of six selected membrane bioreactor (MBR) systems at average and peak flux operation. Each of these systems was operated at peak flux for 4 h a day for six consecutive days to assess peak flux performance. Virus seeding studies were also conducted during peak flux operation to assess the capability of these systems to reject MS-2 coliphage. When operating at steady state, these MBR systems achieved an effluent BOD concentration of <2 mg/L and a turbidity of <0.1 NTU. Peak flux for the MBR systems ranged from 56 to 76 L/m2/h (liters per square meter per hour) with peaking factors in the range of 1.5-3.2. When switching from average to peak flux operation, a reversible drop of 22-32% in temperature-corrected permeability was observed for all submerged MBR systems. The percent drop in permeability increased as MLSS concentration in the membrane tank increased from 11,100 mg/L to 15,300 mg/L and was observed to be highest for the system operating at highest MLSS concentration. Such trends were not observed with an external MBR system. Each MBR system was able to sustain a 4-h-a-day peak flow for six consecutive days with only moderate membrane fouling. The membrane fouling was quantified by measuring the drop in temperature-corrected permeability. This drop ranged from 13 to 33% over six days for different submerged MBR systems. The MBR systems achieved microbial removal in the range of 5.8-6.9 logs for total coliform bacteria, >5.5 to >6.0 logs for fecal coliform bacteria and 2.6 to >3.4 logs for indigenous MS-2 coliphages. When operating at peak flux, seeded MS-2 coliphage removal ranged from 1.0 to 4.4 logs, respectively. The higher log removal values (LRVs) for indigenous MS-2 coliphage among different MBR systems were probably the result of particle association of indigenous coliphage. Differences in membrane pore size (0.04-0.2 microm) amongst the MBR systems evaluated did not have a substantial impact on indigenous MS-2 coliphage removal, but seeded MS-2 coliphage removal varied among the different MBR systems.
一项为期 18 个月的试点研究在加利福尼亚圣地亚哥的 Point Loma 污水处理厂（PLWWTP）进行，以评估六个选定的膜生物反应器（MBR）系统在平均通量和峰值通量运行下的运行和水质性能。这些系统中的每一个都在每天 4 小时的峰值通量下运行 6 天，以评估峰值通量性能。在峰值通量运行期间还进行了病毒接种研究，以评估这些系统拒绝 MS-2 噬菌体的能力。当处于稳定状态时，这些 MBR 系统的出水 BOD 浓度<2mg/L，浊度<0.1NTU。MBR 系统的峰值通量范围为 56-76L/m2/h（每平方米每小时升），峰值因子范围为 1.5-3.2。当从平均通量切换到峰值通量运行时，所有浸没式 MBR 系统的温度校正渗透率可逆下降 22-32%。随着膜罐中 MLSS 浓度从 11100mg/L 增加到 15300mg/L，渗透率的下降百分比增加，并且在 MLSS 浓度最高的系统中观察到最高。这种趋势在外置 MBR 系统中没有观察到。每个 MBR 系统都能够在六天内每天维持 4 小时的峰值流量，只有适度的膜污染。通过测量温度校正渗透率的下降来量化膜污染。在六天内，不同的浸没式 MBR 系统的渗透率下降幅度从 13%到 33%不等。MBR 系统对总大肠菌群的微生物去除率为 5.8-6.9 对数，对粪大肠菌群的去除率为>5.5-6.0 对数，对本地 MS-2 噬菌体的去除率为 2.6-3.4 对数。在峰值通量下运行时，接种的 MS-2 噬菌体的去除率分别为 1.0-4.4 对数。不同 MBR 系统中本地 MS-2 噬菌体的较高对数去除值（LRV）可能是本地噬菌体颗粒结合的结果。评估的 MBR 系统之间的膜孔径（0.04-0.2μm）差异对本地 MS-2 噬菌体的去除没有实质性影响，但接种的 MS-2 噬菌体的去除率在不同的 MBR 系统之间有所不同。
