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Evaporators
An evaporator is a device used to turn the liquid form of a chemical substance, such as water, into a vapor. Uses Air conditioning and refrigeration Some air conditioners and refrigerators use a compressed liquid with a low boiling point, such as chlorodifluoromethane or R-410A, that vaporizes within the system while emitting heat to its surroundings. Food industry and synthetic chemistry Evaporators are used to concentrate a solution. One example is the climbing/falling film plate evaporator, which is used to make condensed milk. Similarly, reduction (cooking) is a process of evaporating liquids from a solution to produce a "reduced" food product, such as wine reduction. Evaporation is the main process behind distillation, which is used to concentrate alcohol, isolate liquid chemical products, or recover solvents in chemical reactions (green chemistry). The fragrance and essential oil industry uses distillation to purify compounds. Each application uses specialized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climbing And Falling Film Plate Evaporator
A climbing/falling film plate evaporator is a specialized type of evaporator in which a thin film of liquid is passed over a rising and falling plate to allow the evaporation process to occur. It is an extension of the falling film evaporator, and has application in any field where the liquid to be evaporated cannot withstand extended exposure to high temperatures, such as the concentration of fruit juices. Design The basic design of the climbing/falling film plate evaporator consists of two phases. In the climbing phase, the liquid feed is heated by a flow of steam as it rises through a corrugated plate. In the subsequent falling phase, the liquid flows downward at high velocity under gravitational force. Evaporation and cooling occurs rapidly in the falling phase. There are several design variations that are commonly used in industrial field. These include single-effect and multiple-effect evaporators. The choice of evaporator design is dictated by constraints of the process. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple-effect Evaporator
A multiple-effect evaporator, as defined in chemical engineering, is an apparatus for efficiently using the heat from steam to evaporate water. Water is boiled in a sequence of vessels, each held at a lower pressure than the last. Because the boiling temperature of water decreases as pressure decreases, the vapor boiled off in one vessel can be used to heat the next, and only the first vessel (at the highest pressure) requires an external source of heat. While in theory, evaporators may be built with an arbitrarily large number of stages, evaporators with more than four stages are rarely practical except in systems where the liquor is the desired product such as in chemical recovery systems where up to seven effects are used. The multiple-effect evaporator was invented by an African-American inventor and engineer Norbert Rillieux. Although he may have designed the apparatus during the 1820s and constructed a prototype in 1834, he did not build the first industrially practical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Exchanger
A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant. Flow arrangement Image:Heat_exc_1-1.svg, Fig. 1: Shell and tube heat exchanger, single pass (1–1 parallel f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfa Laval
Alfa Laval AB is a Sweden, Swedish corporation, company, founded in 1883 by Gustaf de Laval and :sv:Oscar Lamm, Oscar Lamm. The company, which started in providing centrifugal separation solutions for dairy (see Separator (milk)), now deals in the production of specialised products and solutions for heavy industry. The products are used to heat, cool, separate and transport such products as oil, water, chemicals, beverages, foodstuffs, starch and pharmaceuticals. Alfa Laval is headquartered in Lund, Sweden and has Subsidiary company, subsidiary companies in over 100 countries around the world, including South Africa, Denmark, Italy, India, Japan, China, Netherlands, and the United States. As of the end of 2021, Alfa Laval had a global workforce of 18,574 employees and revenue of $4,770.22 million. Company structure and end-markets Alfa Laval is a heavy industry company that focuses on the large-scale operations, such as the Marine, Energy, Food & Water industries. Alfa Laval Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 salinity control, soil desalination, which is an issue for agriculture. Saline water, Saltwater (especially Seawater, sea water) is desalinated to produce water suitable for Drinking water, 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, Reclaimed water, water recycling and water conservation. However, these alternatives are not always available and depletion of reserve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, and plasma), and is the only state with a definite volume but no fixed shape. A liquid is made up of tiny vibrating particles of matter, such as atoms, held together by intermolecular bonds. Like a gas, a liquid is able to flow and take the shape of a container. Most liquids resist compression, although others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density. A distinctive property of the liquid state is surface tension, leading to wetting phenomena. Water is by far the most common liquid on Earth. The density of a liquid is usually close to that of a solid, and much higher than that of a gas. Therefore, liquid and solid are both termed condensed matte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endothermic Process
In thermochemistry, an endothermic process () is any thermodynamic process with an increase in the enthalpy (or internal energy ) of the system.Oxtoby, D. W; Gillis, H.P., Butler, L. J. (2015).''Principle of Modern Chemistry'', Brooks Cole. p. 617. In such a process, a closed system usually absorbs thermal energy from its surroundings, which is heat transfer into the system. Thus, an endothermic reaction generally leads to an increase in the temperature of the system and a decrease in that of the surroundings. It may be a chemical process, such as dissolving ammonium nitrate () in water (), or a physical process, such as the melting of ice cubes. The term was coined by 19th-century French chemist Marcellin Berthelot. The opposite of an endothermic process is an exothermic process, one that releases or "gives out" energy, usually in the form of heat and sometimes as electrical energy. Thus in each term (endothermic and exothermic) the prefix refers to where heat (or electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaporization
Vaporization (or vaporisation) of an element or compound is a phase transition from the liquid phase to vapor. There are two types of vaporization: evaporation and boiling. Evaporation is a surface phenomenon, whereas boiling is a bulk phenomenon. Evaporation is a phase transition from the liquid phase to vapor (a state of substance below critical temperature) that occurs at temperatures below the boiling temperature at a given pressure. Evaporation occurs ''on the surface''. Evaporation only occurs when the partial pressure of vapor of a substance is less than the equilibrium vapor pressure. For example, due to constantly decreasing pressures, vapor pumped out of a solution will eventually leave behind a cryogenic liquid. Boiling is also a phase transition from the liquid phase to gas phase, but boiling is the formation of vapor as bubbles of vapor ''below the surface'' of the liquid. Boiling occurs when the equilibrium vapor pressure of the substance is greater than or equa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evaporation
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidity affects rate of evaporation of water. When the molecules of the liquid collide, they transfer energy to each other based on how they collide. When a molecule near the surface absorbs enough energy to overcome the vapor pressure, it will escape and enter the surrounding air as a gas. When evaporation occurs, the energy removed from the vaporized liquid will reduce the temperature of the liquid, resulting in evaporative cooling. On average, only a fraction of the molecules in a liquid have enough heat energy to escape from the liquid. The evaporation will continue until an equilibrium is reached when the evaporation of the liquid is equal to its condensation. In an enclosed environment, a liquid will evaporate until the surrounding air is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Osmosis
Reverse osmosis (RO) is a water purification process that uses a partially permeable membrane to separate ions, unwanted molecules and larger particles from drinking water. In reverse osmosis, an applied pressure is used to overcome osmotic pressure, a colligative property that is driven by chemical potential differences of the solvent, a thermodynamic parameter. Reverse osmosis can remove many types of dissolved and suspended chemical species as well as biological ones (principally bacteria) from water, and is used in both industrial processes and the production of potable water. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be "selective", this membrane should not allow large molecules or ions through the wiktionary:pore, pores (holes), but should allow smaller components of the solution (such as solvent molecules, e.g., water, H2O) to pass freely. In the normal osmosis process, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinometer
A salinometer is a device designed to measure the salinity, or dissolved salt content, of a solution. Since the salinity affects both the electrical conductivity and the specific gravity of a solution, a salinometer often consist of an ec meter or hydrometer and some means of converting those readings to a salinity reading. A salinometer may be calibrated in either micromhos, a unit of electrical conductivity, (usually 0-22) or else directly calibrated for salt in 'grains per gallon' (0-0.5). A typical reading on-board ship would be 2 micromhos or 0.05 grains per gallon. A reading of twice this may trigger a warning light or alarm. Applications Fresh water generators (Evaporators) use salinometers on the distillate discharge in order to gauge the quality of the water. Water from the evaporator can be destined for potable water supplies, so salty water is not desirable for human consumption. In some ships, extremely high quality distillate is required for use in water-tube boile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
