Reaktiosekoitus

Reaktiosekoitus is the process of mixing reactants inside a chemical reactor to achieve a homogeneous composition and temperature distribution. Effective mixing ensures uniform concentrations, improves heat transfer, and minimizes concentration or temperature gradients that can affect reaction rate, selectivity, and safety. The mixing performance is often described by mixing time, residence time distribution, and the energy input required to achieve the desired level of homogenization.

Mixing is achieved with various devices, including mechanical agitators (impellers such as Rushton turbines or pitched blade turbines), multi-impeller configurations for viscous liquids, and static or dynamic mixing elements. For gas-liquid or liquid-liquid systems, spargers, jet mixers, or emulsifiers may be used. The reactor geometry, baffles, and loading affect flow patterns and energy dissipation, which in turn influence mixing quality.

Key design considerations include liquid properties (viscosity, density, phase behavior), heat generation and removal, and scale-up from laboratory to production scale. Mixing time should be short relative to reaction times in fast reactions; for slow reactions, longer mixing may be acceptable. Poor mixing can cause hotspots, suboptimal yields, or runaway reactions in exothermic systems.

Assessment of mixing performance often uses tracer experiments to obtain residence time distributions or computational fluid dynamics simulations. Reaktiosekoitus is relevant across chemical engineering fields, including chemical synthesis, polymerization, fermentation, and petrochemical processing, where it influences process efficiency and safety.