De Clercq Jeriffa, Jacobs Filip, Kinnear David J, Nopens Ingmar, Dierckx Rudi A, Defrancq Jacques, Vanrolleghem Peter A
Department of Chemical Engineering and Technical Chemistry, Ghent University, Technologiepark 914, 9052 Zwijnaarde, Belgium.
Water Res. 2005 May;39(10):2125-35. doi: 10.1016/j.watres.2005.03.023.
In building and tuning good settling models for secondary clarifiers of wastewater treatment plants, there is a need for measured continuous solids concentration profiles during batch settling. Conventional measuring techniques have difficulties in recording this kind of data, either because they are invasive, or because of the low solids concentration and/or solids density of activated sludge. This paper investigates a novel non-invasive measurement technique borrowed from nuclear medicine, using a solids radiotracer and gamma cameras, to obtain solids concentration profiles during the batch settling of activated sludge, in a pilot-scale column with a height of 1m. The technique does not disturb the settling process, does not alter the settling characteristics, gives profiles every minute and every few millimeters, and is capable of measuring in a range of 0-25 g/l with high accuracy. Dynamic solids concentration profile measurements were performed for sludges of different wastewater treatment plants, and at different initial concentrations. The results show a quantitative representation of the settling process, and reveal hindered and compression settling.
在构建和调整污水处理厂二次沉淀池的良好沉降模型时，需要在间歇沉降过程中测量连续的固体浓度分布。传统的测量技术在记录这类数据时存在困难，要么是因为它们具有侵入性，要么是由于活性污泥的固体浓度低和/或固体密度低。本文研究了一种从核医学借鉴的新型非侵入性测量技术，使用固体放射性示踪剂和伽马相机，在高度为1米的中试规模柱中获取活性污泥间歇沉降过程中的固体浓度分布。该技术不会干扰沉降过程，不会改变沉降特性，每分钟和每隔几毫米给出浓度分布，并且能够在0-25克/升的范围内进行高精度测量。对不同污水处理厂的污泥以及不同初始浓度进行了动态固体浓度分布测量。结果显示了沉降过程的定量表示，并揭示了受阻沉降和压缩沉降。
