Among the various existing technologies for water treatment, the jet clarifier is considered as an effective and compact system as it couples flocculation and clarification in a single unit. In this work, a quasi-two-dimensional apparatus was designed to visualise the interaction between floc size distribution and hydrodynamics in the flocculation zone of a jet clarifier. Measurements of the number of flocs and their size distributions are performed by means of shadowgraphy method and image analysis. Thanks to a coupling between population size distributions and results on local hydrodynamics, the evolution of the number of aggregates along the jet is directly correlated to the recirculation loop present in the flocculation zone. The relative independence of the floc size distributions on the flow rate is discussed in light of the Camp number Gt which remains constant for different flow rates investigated and can thus explain the efficiency of the jet clarifier in terms of flocculation.

在现有的各种水处理技术中，射流澄清器被认为是一种有效且紧凑的系统，因为它将絮凝和澄清结合在一个单元中。在这项工作中，设计了一种准二维装置来可视化喷射澄清器絮凝区中絮体大小分布和流体动力学之间的相互作用。絮凝体的数量及其尺寸分布的测量是通过阴影法和图像分析进行的。由于种群大小分布与局部流体动力学结果之间的耦合，沿射流的聚集体数量的演变与絮凝区中存在的再循环回路直接相关。根据坎普数讨论了絮体大小分布对流速的相对独立性Gt在研究的不同流速下保持恒定，因此可以解释喷射澄清器在絮凝方面的效率。