School of Civil, Environmental and Mining Engineering, The University of Western Australia, 35 Stirling Highway, M015, Crawley 6009, Western Australia, Australia.
Water Res. 2017 Mar 1;110:354-365. doi: 10.1016/j.watres.2016.11.031. Epub 2016 Nov 9.
Waste stabilisation ponds (WSPs) are used worldwide for wastewater treatment, and throughout their operation require periodic sludge surveys. Sludge accumulation in WSPs can impact performance by reducing the effective volume of the pond, and altering the pond hydraulics and wastewater treatment efficiency. Traditionally, sludge heights, and thus sludge volume, have been measured using low-resolution and labour intensive methods such as 'sludge judge' and the 'white towel test'. A sonar device, a readily available technology, fitted to a remotely operated vehicle (ROV) was shown to improve the spatial resolution and accuracy of sludge height measurements, as well as reduce labour and safety requirements. Coupled with a dedicated software package, the profiling of several WSPs has shown that the ROV with autonomous sonar device is capable of providing sludge bathymetry with greatly increased spatial resolution in a greatly reduced profiling time, leading to a better understanding of the role played by sludge accumulation in hydraulic performance of WSPs. The high-resolution bathymetry collected was used to support a much more detailed hydrodynamic assessment of systems with low, medium and high accumulations of sludge. The results of the modelling show that hydraulic performance is not only influenced by the sludge accumulation, but also that the spatial distribution of sludge plays a critical role in reducing the treatment capacity of these systems. In a range of ponds modelled, the reduction in residence time ranged from 33% in a pond with a uniform sludge distribution to a reduction of up to 60% in a pond with highly channelized flow. The combination of high-resolution measurement of sludge accumulation and hydrodynamic modelling will help in the development of frameworks for wastewater sludge management, including the development of more reliable computer models, and could potentially have wider application in the monitoring of other small to medium water bodies, such as channels, recreational water bodies, and commercial ports.
污水稳定塘（WSP）被广泛用于世界各地的废水处理，在其运行过程中需要定期进行污泥调查。WSP 中的污泥积累会通过减少池塘的有效容积，以及改变池塘水力和废水处理效率，从而影响其性能。传统上，污泥高度（因此也是污泥体积）是通过低分辨率且劳动强度大的方法来测量的，例如“污泥判断”和“白毛巾测试”。事实证明，安装在遥控潜水器（ROV）上的声纳设备作为一种现成的技术，能够提高污泥高度测量的空间分辨率和准确性，同时减少劳动力和安全要求。结合专用软件包，对几个 WSP 的剖面测量表明，配备自主声纳设备的 ROV 能够以大大减少的剖面时间提供具有大大提高的空间分辨率的污泥地形测量，从而更好地了解污泥积累在 WSP 水力性能中的作用。所收集的高分辨率地形数据用于支持对低、中、高污泥积累的系统进行更详细的水动力评估。建模结果表明，水力性能不仅受到污泥积累的影响，而且污泥的空间分布在降低这些系统的处理能力方面起着关键作用。在所模拟的一系列池塘中，停留时间的减少范围从污泥分布均匀的池塘中的 33%到污泥高度渠道化流动的池塘中的高达 60%。污泥积累的高分辨率测量和水动力建模的结合将有助于废水污泥管理框架的开发，包括开发更可靠的计算机模型，并且可能在监测其他中小水体（如渠道、娱乐水体和商业港口）方面具有更广泛的应用。
