Separation process - Citizendia

In chemistry and chemical engineering, a separation process is used to transform a mixture of substances into two or more distinct products. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Chemical engineering is the branch of Engineering that deals with the application of Physical science (e In Chemistry, a mixture is a substance made by combining two or more different materials without a chemical reaction occurring (the objects do not bond together The separated products could differ in chemical properties or some physical property, such as size, or crystal modification or other.

Barring a few exceptions, almost every element or compound is found naturally in an impure state such as a mixture of two or more substances. A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. Many times the need to separate it into its individual components arises. Separation applications in the field of chemical engineering are very important. Chemical engineering is the branch of Engineering that deals with the application of Physical science (e A good example is that of crude oil. Petroleum ( L petroleum, from Greek πετρέλαιον, lit Crude oil is a mixture of various hydrocarbons and is valuable in this natural form. Demand is greater, however, for the purified various hydrocarbons such as natural gases, gasoline, diesel, jet fuel, lubricating oils, asphalt,etc.

Separation processes can essentially be termed as mass transfer processes. Mass transfer is the phrase commonly used in engineering for physical processes that involve molecular and convective transport of Atoms and Molecules The classification can be based on the means of separation, mechanical or chemical. The choice of separation depends on the pros and cons of each. Mechanical separations are usually favored if possible due to the lower cost of the operations as compared to chemical separations. Systems that can not be separated by purely mechanical means (e. g. crude oil), chemical separation is the remaining solution. The mixture at hand could exist as a combination of any two or more states: solid-solid, solid-liquid, solid-gas, liquid-liquid, liquid-gas, gas-gas, solid-liquid-gas mixture, etc.

Depending on the raw mixture, various processes can be employed to separate the mixtures. Many times two or more of these processes have to be used in combination to obtain the desired separation. In addition to chemical processes, mechanical processes can also be applied where possible. In the example of crude oil, one upstream distillation operation will feed its two or more product streams into multiple downstream distillation operations to further separate the crude, and so on until final products are purified. Downstream processing refers to the recovery and purification of biosynthetic products particularly pharmaceuticals from natural sources such as animal or plant tissue or fermentation

Various types of separation processes

Adsorption
Centrifugation and Cyclones - density differences
Chromatography involves the separation of different dissolved substances as they travel through a material. Adsorption is a process that occurs when a gas or liquid Solute accumulates on the surface of a solid or a liquid (adsorbent forming a film of molecules or atoms (the Centrifugation is a process that involves the use of the Centrifugal force for the separation of mixtures used in industry and in laboratory settings Cyclonic separation is a method of removing Particulates from an air gas or water stream without the use of filters through Vortex separation Chromatography (from Greek χρώμα chroma, color and γραφειν"graphein" to write is the collective term for a family of Laboratory The dissolved substances are separated based on their interaction with the stationary phase.
Crystallization
Decantation
Demister (Vapor) - removing liquid droplets from gas streams
Dissolved air flotation - suspended solids are encouraged to float to the top of a fluid by rising air bubbles. Crystallization is the (natural or artificial process of formation of solid Crystals precipitating from a homogeneous --> identical Solution Decantation is a process for the Separation of mixtures carefully pouring a solution from a container leaving the Precipitate ( Sediments in the bottom A demister, is a device often fitted to vapor liquid separator vessels to enhance the removal of liquid droplets entrained in a vapor stream Dissolved air flotation (DAF is a Water treatment process that clarifies Wastewaters (or other waters by the removal of suspended matter such as oil or solids
Distillation - used for mixtures of liquids with different boiling points, or for a solid dissolved in a liquid. Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture
Drying - removing liquid from a solid by vaporising it
Electrophoresis Organic molecules, such as protein are placed in a gel. Drying is a Mass transfer process resulting in the removal of water Moisture or moisture from another Solvent, by Evaporation from a Solid Electrophoresis is the most well-known electrokinetic phenomenon. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl A gel (from the lat gelu &mdashfreezing cold ice or gelatus &mdashfrozen immobile is an apparently solid jelly-like material formed from a A voltage is applied and the molecules move through the gel because they are charged. Electrical tension (or voltage after its SI unit, the Volt) is the difference of electrical potential between two points of an electrical Electric charge is a fundamental conserved property of some Subatomic particles which determines their Electromagnetic interaction. The gel restricts the motion so that different proteins will make different amounts of progress in any given time.
Elutriation
Evaporation
Extraction
- Leaching
- Liquid-liquid extraction
- Solid phase extraction
Flocculation - density differences utilization a flocculant such as soap or detergent
Fractional freezing
Filtration. Elutriation, also known as air classification, is a process for separating lighter particles from heavier ones using a vertically-directed stream of Gas or Evaporation is the process by which Molecules in a Liquid state (e Liquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two Solid-phase extraction ( SPE) is a Separation process that is used to remove solid or semi-solid compounds from a mixture of impurities based on their physical and Flocculation is a process where a Solute comes out of Solution in the form of floc or flakes Fractional freezing is a process used in Process engineering and Chemistry to separate two liquids with different melting points Filtration is a mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases by interposing a medium to fluid flow through which the fluid Mesh, bag and paper filters are used to remove large particulates suspended in fluids, eg. A mesh is a flat semi-permeable barrier made of connected strands of Metal, Fiber, or other flexible/ductile material fly ash, while membrane processes including microfiltration, ultrafiltration, nanofiltration, reverse osmosis, dialysis (biochemistry) utilising synthetic membranes can separate micrometre-sized or smaller species. Fly ash is one of the residues generated in the Combustion of Coal. Microfiltration is a Filtration process which removes Contaminants from a Fluid (liquid & gas by passage through a microporous membrane. Nanofiltration is a relatively recent membrane process used most often with low Total dissolved solids water such as Surface water and fresh groundwater with the Reverse osmosis (RO is a separation process that uses pressure to force a Solution through a membrane that retains the Solute on one side and allows the In Biochemistry, dialysis is the process of separating Molecules in Solution by the difference in their rates of Diffusion through a semipermeable An artificial membrane, also called a synthetic membrane, is a membrane prepared for separation tasks in Laboratory and industry A micrometre ( American spelling: micrometer; symbol µm) is one millionth of a Metre, or equivalently one thousandth of a Millimetre
Oil-water separation - gravimetric separator used to remove suspended oil droplets from wastewaters in oil refineries, petrochemical and chemical plants, natural gas processing plants and similar industries. An oil refinery is an industrial Process plant where Crude oil is processed and refined into more useful Petroleum products, such as Gasoline Petrochemicals are chemical products made from raw materials of Petroleum or other Hydrocarbon origin A chemical plant is industrial process plant that manufactures (or otherwise processes Chemicals usually on a large scale Natural gas processing plants or fractionators are used to purify the raw Natural gas extracted from underground gas fields and brought up to the surface by
Precipitation
Recrystallization
Sedimentation - density differences
- Gravity separation
Sieving
Stripping
Sublimation
Vapor-liquid separation - designed by using the Souders-Brown equation. Precipitation is the formation of a Solid in a Solution during a Chemical reaction. Recrystallization (see also Crystallization) is a physical process that has meanings in Chemistry, Metallurgy and Geology. Sedimentation describes the motion of Molecules in Solutions or particles in suspensions in response to an external force such as gravity Gravity separation is an industrial method of separating two components from a suspension or any other homogeneous mixture where separating the components with gravity is sufficiently Stripping is a chemical Separation process where one or more components are removed from a liquid stream by a vapor stream Sublimation of an element or compound is a transition from the Solid to Gas phase with no intermediate liquid stage The Souders-Brown equation has been the tool for obtaining the maximum allowable vapor Velocity in vapor-liquid separation vessels (variously called flash drums
Winnowing
Zone refining

Various types of separation processes

See also