Unit operations Unit operations Aqueous biphasic systems (ABS) or aqueous two phase systems are clean alternatives for traditional organic- water solvent extraction systems. ABS are formed when 2 polymers, one polymer and one kosmotropic salt, or two salts (one chaotropic salt and the other a kosmotropic salt) are mixed together at appropriate concentrations or at a particular temperature. The two phases are mostly composed of water and non volatile components, thus eliminating volatile organic compounds. They have been used for many years in biotechnological applications as denaturing and benign separation media. Recently, they have been used for metal ion separations, environmental remediation,mettalurgical applications and as a reaction media. ...more on Wikipedia about "Aqueous two phase system"
Centrifugation is a process that involves the use of the centrifugal force for the separation of mixtures. ...more on Wikipedia about "Centrifugation"
Extrusion is a manufacturing process where a material, often in the form of a billet, is pushed and/or drawn through a die to create long objects of a fixed cross-section. Hollow sections are usually extruded by placing a pin or mandrel in the die. Extrusion may be continuous (producing indefinitely long material) or semi-continuous (repeatedly producing many shorter pieces). Some materials are hot drawn whilst other may be cold drawn. ...more on Wikipedia about "Extrusion"
A falling film evaporator is a device used industrially to concentrate solutions, especially solutions with heat sensitive components. The evaporator is a specialized heat exchanger; it consists of an outer shell which is filled with steam, and a number of vertical, parallel tubes through with the solution falls in a thin film. The pressure in the tubes may be lower than atmospheric pressure, in order to depress the solution's boiling point. A proportion of the water in the solution evaporates and is evacuated from the system; the concentrated solution is collected at the bottom of the evaporator. ...more on Wikipedia about "Falling film evaporator"
In chemistry and alchemy, filtration is the process of using a filter to mechanically separate a mixture. ...more on Wikipedia about "Filtration"
Flotation is a method for the separation of mixtures. Flotation is a separation technique used widely in the minerals industry, for paper, de-inking, and water treatment amongst others. It can also be used in the food and coal industries. The technique relies upon differences in the surface properties of different particles to separate them. The particles that are to be floated are rendered hydrophobic by the addition of the appropriate chemicals. Air is then bubbled through the mixture and the desired particles become attached to the small air bubbles and move to the surface where they accumulate as a froth and are collected, or if the non-desired particles float to the surface they are collected and discarded. The flotation process was developed on a commercial scale early in the 20th century and is widely used for processing of silver. ...more on Wikipedia about "Flotation"
Fractional freezing is a process used by chemists to separate two liquids which have a different freezing point. This happens by dropping the temperature of both liquids - one liquid will reach its freezing point and solidify, while the other will remain liquid. This liquid can be poured off, leaving the solid to warm and return to its liquid state. ...more on Wikipedia about "Fractional freezing"
Fractionation is a separation process in which a certain quantity of a mixture (solid, liquid, solute or suspension) is divided up in a large number of smaller quantities ( fractions) in which the composition changes according to a gradient. Fractions are collected based on differences in a specific property of the individual components. Common trait in fractionations is the need to find an optimum between the amount of fractions collected and the desired purity in each fraction. Fractionation makes it possible to isolate more than two components in a mixture in a single run. This property sets it apart from other separation techniques. ...more on Wikipedia about "Fractionation"
Freeze drying (also known as Lyophilization) is a dehydration process typically used to preserve a perishable material or make the material more convenient for transport. Freeze drying works by freezing the material and then reducing the surrounding pressure to allow the frozen water in the material to sublimate directly from the solid phase to gas. Sublimation gradually causes shrinkage of unused ice cubes in frost-free freezers and the disappearance of winter snow without thawing. ...more on Wikipedia about "Freeze drying"
Froth Flotation is a selective process for separating minerals from gangue by using surfactants and wetting agents. The selective separation of the minerals makes processing complex (that is, mixed) orebodies economically feasible. The flotation process is used for the separation of a large range of sulfides, carbonates and oxides prior to further refinement. Phosphate and coal are also processed by flotation technology. ...more on Wikipedia about "Froth flotation"
Homogenization is a term used both in agricultural science and in cell biology. ...more on Wikipedia about "Homogenization"
Kinetic fractionation is a process that separates stable isotopes from each other by their mass. It is a unidirectional process. ...more on Wikipedia about "Kinetic fractionation"
In chemistry, liquid-liquid extraction (or more briefly, solvent extraction) is a useful method to separate components (compounds) of a mixture. The success of this method depends upon the difference in solubility of a compound in various solvents. ...more on Wikipedia about "Liquid-liquid extraction"
In industrial process engineering, mixing is a unit operation that involves manipulating a heterogeneous physical system, with the intent to make it more homogeneous. Familiar examples include pumping of the water in a swimming pool to homogenize the water temperature, and the stirring of pancake batter to eliminate lumps. This concept is captured formally in physics, where the mixing of dynamical systems is a topic studied in its own right. In mathematics, the concept of mixing is formally defined for measure-preserving dynamical systems and stochastic processes, and includes the ideas of strong mixing, weak mixing and topological mixing. ...more on Wikipedia about "Mixing (process engineering)"
Packaging is the enclosing of a physical object, typically a product that will be offered for sale. Labelling ( CwE) or labeling ( AmE) refers to any written or graphic communications on the packaging or on a separate label. ...more on Wikipedia about "Packaging and labelling"
Pasteurization (or pasteurisation) is the process of heating food for the purpose of killing harmful organisms such as bacteria, viruses, protozoa, molds, and yeasts. The process was named after its inventor, French scientist Louis Pasteur. The first pasteurization test was completed by Pasteur and Claude Bernard on April 20, 1862. ...more on Wikipedia about "Pasteurization"
In chemistry and chemical engineering, a separation process is a process that transforms a mixture of substances into two or more compositionally-distinct products. ...more on Wikipedia about "Separation process"
Barring a few exceptions, almost every element or compound is found in an impure state i.e. as a mixture of two or more substances - thus the need to separate it into its individual components so as to make it more productive. Its applications in the field of chemical engineering can be very important. The best example that can be cited here is that of crude. Crude is a mixture of various hydrocarbons (though valuable in itself), there is a greater demand for the various hydrocarbons that it is a mixture of, viz. gasoline, diesel, etc. Enter separation processes!! ...more on Wikipedia about "Separation processes"
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