1 Application scope and type
1.0.1 Application scope
Static mixers are used in liquid-liquid, liquid-gas, liquid-solid, gas-gas mixing, emulsification, neutralization, absorption, extraction, reaction, heat transfer enhancement and other processes. They can be applied within a wide range of fluid viscosities (about 106mPa•s), in different flow patterns (laminar, transition, turbulent, and fully turbulent flows), either operated intermittently or continuously, and they are easy to be scaled up directly. The following is a brief description of them based on their classification.
1.0.1.1 Liquid-liquid mixing process: the fluids with the flow pattern ranging from laminar flow to turbulent flow or a viscosity ratio as large as 1: 106mPa•s can be well mixed, with the dispersed droplets having a uniform size and a minimum diameter up to 1~2μm.
1.0.1.2 Liquid-gas mixing process: the two-phase liquid-gas component may cause continuous renewal and sufficient contact at the phase interface, which can replace the bubble column or part of the orifice column.
1.0.1.3 Liquid-solid mixing process: when a small number of solid particles or powder (with solids accounting for about 5% of the volume of the liquid) and the liquid are mixed under turbulent conditions, the solid particles or powder are forced to be fully dispersed to achieve liquid extraction or decolorization.
1.0.1.4 Gas-gas mixing process: the mixing of cold and hot gases and the mixing of gases with different components.
1.0.1.5 Heat transfer enhancement: compared with empty pipe, the heat transfer coefficient of static mixer is 8 times higher for hot gas cooling or cold gas heating with a small heat transfer coefficient, 5 times higher for the heating of viscous fluid and 8.5 times higher for the condensation in the presence of a large number of non-condensable gases; and for high polymer melt, it may reduce the temperature and viscosity gradient of the melt on the pipe section.
1.0.2 Type and structure of static mixer
1.0.2.1 This standard is prepared on the example of five types of static mixer series products: SV, SX, SL, SH and SK (Note①).
1.0.2.2 Due to the differences in the structures of the mixing unit internals, the application scenarios and the application effects, and the selection shall be made based on different application scenarios and technical requirements.
1.0.2.3 A comparison of the applications and performances of the five types of static mixer products is shown in Tables 1.0.2-1 and 1.0.2-2, and the schematic diagram for structure is shown in Figure 1.0.2. A static mixer consists of three parts: shell, mixing unit internals and connecting flange.
1 Application scope and type
2 Determination of main technical parameters
3 Trial calculation using examples
4 Precautions for use
5 Primary selection data sheet and summary list of static mixer
6 Parameter lists of five types of static mixers
7 Explanation of symbols
