Study on Mixing Efficiency Evaluation Factor Named Mixing Factor Based on Gridding Control

Mixing is a significant process in water and wastewater treatment process. Its efficiency will greatly influence the operating states, quality of effluent and operation costs of sequential treating processes. According to mathematic analysis, a new evaluation factor for mixing efficiency named mixing factor (l
_H
) was put forward for the first time in this paper, and it was a comprehensive index which could reflect the mixing efficiency and energy consumption. In this study, blank test, type test and analysis test were carried out respectively via pipe mixing. The results showed that the optimal disturbed flow equipment type was gridding group, the optimal control designing parameters were as follow: line-diameter ratio was 1:4, rib width was 10 mm, velocity of pipe was 0.4 m/s ~0.6 m/s, mixing efficiency as well as mixing factor (l
_H
) were greater than or equal to 97.5% and 1.81 respectively.