The ability to quantify liquid motion in a stirred tank is a basic step toward understanding how mixing influences process results. Quantifying mixing according to a mixing index (MI) can evaluate and predict mixing intensity related to fluid velocities in…
Fractional crystallization is a stage-wise separation technique that relies upon the liquid-solid phase change and enables the purification of multi-component mixtures, as long as none of the constituents can act as a solvent to the others. Thanks to the level…
Stainless steels are common materials for process equipment and components in the chemical process industries in large part because of their corrosion resistance. This one-page reference reviews the properties of stainless steels with regard to corrosion resistance. Passive layer Stainless…
In a typical bulk-solids pneumatic-conveying system, an air mover is used to generate the necessary air flowrate and pressure required to transport a solid material through a pipeline at a given rate. This one-page reference discusses the operating mechanisms and…
Liquid-liquid extraction (LLE) is a separation technique that exploits differences in the relative solubility of compounds of interest (the solute) in two immiscible liquids — most often an aqueous phase and an organic solvent. This one-page reference reviews basic information…
In crossflow membrane filtration (CMF), feed flow is parallel to the filtration surface (rather than perpendicular to it, as in conventional filtration). During a given pass, a portion of the feed permeates the membrane, while a larger portion is retained…
When evaluating capital projects in the chemical process industries (CPI), there are many scenarios in which there are important differences between the alternatives in terms of capital, operations and maintenance and decommissioning costs. In these cases, decisions must be made…
Injecting gases through a diffuser into a liquid is an important aspect of many operations in the chemical process industries (CPI). Important applications include dissolving reactant gases into a liquid phase for further reaction (such as in hydrogenation, oxidation, ozonation),…
Heat transfer fluids (HTFs) provide heating and cooling of process equipment, including reactors, autoclaves, distillation columns, reboilers, mixers and dryers. HTF system designs should provide for effective system venting, both of residual water at startup and of degradation products during…
Alternating-current (a.c.) induction motors are widely used throughout the chemical process industries (CPI) and other manufacturing sectors to convert electrical energy into mechanical energy to power rotating equipment, such as centrifugal pumps, compressors and fans, as well as other industrial…