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Demister (Vapor)
A demister is a device often fitted to vapor–liquid separator vessels to enhance the removal of liquid droplets entrained in a vapor stream. Demisters may be a mesh-type coalescer, vane pack or other structure intended to aggregate the mist into droplets that are heavy enough to separate from the vapor stream. Demisters can reduce the residence time required to separate a given liquid droplet size by reducing the volume and associated cost of separator equipment. Demisters are often used where vapor quality is important in regard to entrained liquids, particularly where separator equipment costs are high (e.g., high-pressure systems) or where space or weight savings are advantageous. For example, in the process of brine desalination on marine vessels, brine is flash-heated into vapor. In flashing, vapor carries over droplets of brine, which have to be separated before condensing, otherwise the distillate vapor would be contaminated with salt. This is the role of the demi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor–liquid Separator
In chemical engineering, a vapor–liquid separator is a device used to separate a vapor–liquid mixture into its constituent phases. It can be a vertical or horizontal vessel, and can act as a 2-phase or 3-phase separator. A vapor–liquid separator may also be referred to as a ''flash drum'', ''breakpot'', ''knock-out drum'' or ''knock-out pot'', ''compressor suction drum, suction scrubber'' or ''compressor inlet drum,'' or ''vent scrubber.'' When used to remove suspended water droplets from streams of air, it is often called a demister. Method of operation In vapor-liquid separators gravity is utilized to cause the denser fluid (liquid) to settle to the bottom of the vessel where it is withdrawn, less dense fluid (vapor) is withdrawn from the top of the vessel. In low gravity environments such as a space station, a common liquid separator will not function because gravity is not usable as a separation mechanism. In this case, centrifugal force needs to be utilised i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entrainment (engineering)
:''See entrainment for other types.'' In engineering, entrainment is the entrapment of one substance by another substance. For example: * The entrapment of liquid droplets or solid particulates in a flowing gas, as with smoke. * The entrapment of gas bubbles or solid particulates in a flowing liquid, as with aeration. * Given two mutually insoluble liquids, the emulsion of droplets of one liquid into the other liquid, as with margarine. * Given two gases, the entrapment of one gas into the other gas. * "Air entrainment Air entrainment in concrete is the intentional creation of tiny air bubbles in a batch by adding an air entraining agent during mixing. A form of surfactant (a surface-active substance that in the instance reduces the surface tension between wa ..." - The intentional entrapment of air bubbles into concrete. * Entrainment defect in metallurgy, as a result of folded pockets of oxide inside the melt. See also * Souders-Brown equation References Chemical en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coalescer
A coalescer is a device which induces coalescence in a medium. They are primarily used to separate emulsions into their components via various processes, operating in reverse to an emulsifier. Coalescers are of two main types: mechanical and electrostatic. Mechanical coalescers use filters or baffles to make droplets coalesce, while electrostatic coalescers use DC or AC electric fields (or combinations). Mechanical coalescers Mechanical coalescers, which are the more common type of coalescers, operate by physically altering a droplet by ''mechanical'' means. They are commonly applied in the global oil and gas industries for the removal of water or hydrocarbon condensate. While coalescers by definition function as a separation tool for liquids, they are also used, and mistakenly referred to, as filters. In the area of compressed air purification, coalescing filters are used to separate liquid water and oil from compressed air using a coalescing effect. Coalescence (physics) show ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor Quality
In physics, a vapor (American English) or vapour (British English and Canadian English; see spelling differences) is a substance in the gas phase at a temperature lower than its critical temperature,R. H. Petrucci, W. S. Harwood, and F. G. Herring, ''General Chemistry'', Prentice-Hall, 8th ed. 2002, p. 483–86. which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is different from an aerosol. An aerosol is a suspension of tiny particles of liquid, solid, or both within a gas. For example, water has a critical temperature of , which is the highest temperature at which liquid water can exist. In the atmosphere at ordinary temperatures gaseous water (known as water vapor) will condense into a liquid if its partial pressure is increased sufficiently. A vapor may co-exist with a liquid (or a solid). When this is true, the two phases will be in equilibrium, and the gas-partial pressure will be equal to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brine
Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking ( pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization ( fresh water recovery). In nature Brines are produced in multiple ways in nature. Modification of seawater via evaporation results in the concentration of salts in the residual fluid, a characteristic geologic depos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Desalination
Desalination is a process that takes away mineral components from saline water. More generally, desalination refers to the removal of salts and minerals from a target substance, as in soil desalination, which is an issue for agriculture. Saltwater (especially sea water) is desalinated to produce water suitable for human consumption or irrigation. The by-product of the desalination process is brine. Desalination is used on many seagoing ships and submarines. Most of the modern interest in desalination is focused on cost-effective provision of fresh water for human use. Along with recycled wastewater, it is one of the few rainfall-independent water resources. Due to its energy consumption, desalinating sea water is generally more costly than fresh water from surface water or groundwater, water recycling and water conservation. However, these alternatives are not always available and depletion of reserves is a critical problem worldwide. Desalination processes are usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Evaporation
Flash evaporation (or partial evaporation) is the partial vapor that occurs when a saturated liquid stream undergoes a reduction in pressure by passing through a throttling valve or other throttling device. This process is one of the simplest unit operations. If the throttling valve or device is located at the entry into a pressure vessel so that the flash evaporation occurs within the vessel, then the vessel is often referred to as a flash drum. If the saturated liquid is a single-component liquid (for example, propane or liquid ammonia), a part of the liquid immediately "flashes" into vapor. Both the vapor and the residual liquid are cooled to the saturation temperature of the liquid at the reduced pressure. This is often referred to as "auto-refrigeration" and is the basis of most conventional vapor compression refrigeration systems. If the saturated liquid is a multi-component liquid (for example, a mixture of propane, isobutane and normal butane), the flashed vapor is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distillate
Distillation, or classical distillation, is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation, usually inside an apparatus known as a still. Dry distillation is the heating of solid materials to produce gaseous products (which may condense into liquids or solids); this may involve chemical changes such as destructive distillation or cracking. Distillation may result in essentially complete separation (resulting in nearly pure components), or it may be a partial separation that increases the concentration of selected components; in either case, the process exploits differences in the relative volatility of the mixture's components. In industrial applications, distillation is a unit operation of practically universal importance, but is a physical separation process, not a chemical reaction. An installation used for distillation, especially of distilled beverages, is a distillery. Distillation includes the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantities in seawater. The open ocean has about of solids per liter of sea water, a salinity of 3.5%. Salt is essential for life in general, and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food, including otherwise unpalatable food. Salting, brining, and pickling are also ancient and important methods of food preservation. Some of the earliest evidence of salt processing dates to around 6,000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt-works in China dates to approximately the same period. Salt was also prized by the ancient Hebrews, Greeks, Romans, By ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor–liquid Separator
In chemical engineering, a vapor–liquid separator is a device used to separate a vapor–liquid mixture into its constituent phases. It can be a vertical or horizontal vessel, and can act as a 2-phase or 3-phase separator. A vapor–liquid separator may also be referred to as a ''flash drum'', ''breakpot'', ''knock-out drum'' or ''knock-out pot'', ''compressor suction drum, suction scrubber'' or ''compressor inlet drum,'' or ''vent scrubber.'' When used to remove suspended water droplets from streams of air, it is often called a demister. Method of operation In vapor-liquid separators gravity is utilized to cause the denser fluid (liquid) to settle to the bottom of the vessel where it is withdrawn, less dense fluid (vapor) is withdrawn from the top of the vessel. In low gravity environments such as a space station, a common liquid separator will not function because gravity is not usable as a separation mechanism. In this case, centrifugal force needs to be utilised i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
