The tubular static mixer is an ideal device for the instantaneous mixing of water with coagulants, flocculants, and disinfectants. It features high mixing efficiency, reduced chemical consumption, and a compact design. Composed of a set of two mixing units, it operates without external power, relying on water flow to generate three effects: flow splitting, cross-mixing, and reverse swirling, achieving a mixing efficiency of 90–95%. Design specifications: (1) The pipe diameter of the mixer is selected based on the economic flow velocity, generally calculated at 0.9–1.2 m/s. For pipe diameters exceeding 500 mm, the maximum flow velocity can reach 1.5 m/s. If conditions permit, increasing the pipe diameter by 50–100 mm can reduce head loss. (2) The basic configuration of the mixer consists of three sections, with a head loss of approximately 0.4–0.6 m. The number of sections can be adjusted based on the mixing medium.