In this article I write about process technologies for preparation of slurries, AKA “solids in suspension,” and the considerations that must be made in equipment design. Mainly this includes powder wettability, but I will also briefly outline reactions, rheology, and several other considerations. For slurry preparation, our initial state is one in which the dry […]
Inline mixers can be defined as a configuration where the materials to be mixed are flowing continuously through the device. Residence time is generally short, on the order of seconds. Oftentimes, plug-flow behavior (minimal back-mixing) can be approached. Inline mixers are used because of the general compactness and simplicity of the equipment relative to tank […]
When formulating complex products, stirred tanks are traditionally used because of inherent advantages in semi-batch operations. While there is interest in moving from batch to continuous processes in the context of process intensification [1], a semi-batch stirred tank will remain the best option for complex formulations. For instance, a single stirred tank can be designed […]
“Say it, don’t spray it.” Generally, this is good advice, but in industry it’s often profitable to spray it. In simple terms, sprays mix liquid droplets into gas, often with the aim to generate high interfacial area. In the process industries, the use of sprays is widespread. For instance: Thermal quenching/cooling of hot gas, liquid, […]
“My reaction is done in a few seconds; therefore, I can’t have a mixing problem.” Mixing experts hear this frequently, but is it true? Actually, because the reaction is fast, mixing is more likely to affect the reaction rate. However, to more fully address the question, imagine a reaction takes 10 seconds to complete. Is […]
