Performance Evaluation of Water Treatment Helically Coiled Tube Flocculators using Computational Fluid Dynamics

Helically Coiled Tube Flocculators (HCTF), which are hydraulic types of water treatment flocculators, have various applications, such as in the food industry. These flocculators have been considered due to their high ability in producing large flocs and significant reduction of water turbidity. The design and production of these flocculators have usually been associated with many problems. One of the main problems is the high cost and time-consuming production of laboratory samples to study and understand the effect of various design parameters on floc size and output water quality. Another problem of the experimental study of these flocculators is the high cost of its tests and the lack of laboratory space. The purpose of this study is to investigate the effect of design input parameters on improving the performance of helical hydraulic flocculation; this study is done using numerical simulation of the flocculator. The optimal flocculation performance in this study is defined as the lowest distribution of Gp (local velocity gradient) in the flocculator and the least backmixing of particles in the inlet water. According to the results, the flow rate has the greatest impact on the Gp distribution and can reduce it by up to ۵۰%. On the other hand, the diameter of the pipe has the greatest influence on backmixing and its proper selection can reduce backmixing by more than ۴۰%.

کلیدواژه ها:

Water treatment ، Tube flocculator ، CFD ، Hydraulic flocculator