|
Filtered
Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter medium are described as ''oversize'' and the fluid that passes through is called the ''filtrate''. Oversize particles may form a filter cake on top of the filter and may also block the filter lattice, preventing the fluid phase from crossing the filter, known as ''blinding''. The size of the largest particles that can successfully pass through a filter is called the effective ''pore size'' of that filter. The separation of solid and fluid is imperfect; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size, filter thickness and biological activity). Filtration occurs both in nature and in engineered systems; there are biological, geological, and industrial forms. Filtration is also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basking Shark
The basking shark (''Cetorhinus maximus'') is the second-largest living shark and fish, after the whale shark, and one of three plankton-eating shark species, along with the whale shark and megamouth shark. Adults typically reach in length. It is usually greyish-brown, with mottled skin, with the inside of the mouth being white in color. The caudal fin has a strong lateral keel and a crescent shape. Other common names include bone shark, elephant shark, sail-fish, and sun-fish. In Orkney, it is commonly known as hoe-mother (sometimes contracted to homer), meaning "the mother of the pickled dog-fish". The basking shark is a cosmopolitan migratory species, found in all the world's temperate oceans. A slow-moving filter feeder, its common name derives from its habit of feeding at the surface, appearing to be basking in the warmer water there. It has anatomical adaptations for filter-feeding, such as a greatly enlarged mouth and highly developed gill rakers. Its snout is conic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Activated Carbon
Activated carbon, also called activated charcoal, is a form of carbon commonly used to filter contaminants from water and air, among many other uses. It is processed (activated) to have small, low-volume pores that increase the surface area available for adsorption (which is not the same as absorption) or chemical reactions. Activation is analogous to making popcorn from dried corn kernels: popcorn is light, fluffy, and has a surface area that is much larger than the kernels. ''Activated'' is sometimes replaced by ''active''. Due to its high degree of microporosity, one gram of activated carbon has a surface area in excess of as determined by gas adsorption. Charcoal, before activation, has a specific surface area in the range of . An activation level sufficient for useful application may be obtained solely from high surface area. Further chemical treatment often enhances adsorption properties. Activated carbon is usually derived from waste products such as coconut husks; waste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Charge
Surface charge is a two-dimensional surface with non-zero electric charge. These electric charges are constrained on this 2-D surface, and surface charge density, measured in coulombs per square meter (C•m−2), is used to describe the charge distribution on the surface. The electric potential is continuous across a surface charge and the electric field is discontinuous, but not infinite; this is unless the surface charge consists of a dipole layer. In comparison, the potential and electric field both diverge at any point charge or linear charge. In physics, at equilibrium, an ideal conductor has no charge on its interior; instead, the entirety of the charge of the conductor resides on the surface. However, this only applies to the ideal case of infinite electrical conductivity; The majority of the charge of an actual conductor resides within the skin depth of the conductor's surface. For dielectric materials, upon the application of an external electric field, the positive charg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. Biological membranes include cell membranes (outer coverings of cells or organelles that allow passage of certain constituents); nuclear membranes, which cover a cell nucleus; and tissue membranes, such as mucosae and serosae. Synthetic membranes are made by humans for use in laboratories and industry (such as chemical plants). This concept of a membrane has been known since the eighteenth century but was used little outside of the laboratory until the end of World War II. Drinking water supplies in Europe had been compromised by the war and membrane filters were used to test for water safety. However, due to the lack of reliability, slow operation, reduced selectivity and elevated costs, membranes were not widely exploited. The first us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filter Cake
A filter cake is formed by the substances that are retained on a filter. Filter aids, such as diatomaceous earth or activated carbon are usually used to form the filter cake. The purpose is to increase flow rate or achieve a smaller micron filtration. The filter cake grows in the course of filtration, becoming "thicker" as particulate matter and filter aid is retained on the filter. With increasing layer thickness, the flow resistance of the filter cake increases. After a time, the filter cake has to be removed from the filter, e.g. by backflushing. If this is not accomplished, the filtration is disrupted because the viscosity of the filter cake gets too high; hence, too little of the mixture to be filtered can pass through the filter cake and the filter plugs. The specifications of the filter cake dictate the filtration method of choice. See also * Filter press * Tilting pan filter A tilting pan filter is a chemical equipment used in continuous solid- liquid filtration. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Particle Size Distribution
The particle-size distribution (PSD) of a powder, or granular material, or particles dispersed in fluid, is a list of values or a mathematical function that defines the relative amount, typically by mass, of particles present according to size. Significant energy is usually required to disintegrate soil, etc. particles into the PSD that is then called a grain size distribution. Significance The PSD of a material can be important in understanding its physical and chemical properties. It affects the strength and load-bearing properties of rocks and soils. It affects the reactivity of solids participating in chemical reactions, and needs to be tightly controlled in many industrial products such as the manufacture of printer toner, cosmetics, and pharmaceutical products. Significance in the collection of particulate matter Particle size distribution can greatly affect the efficiency of any collection device. Settling chambers will normally only collect very large particles, those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sieve
A sieve, fine mesh strainer, or sift, is a device for separating wanted elements from unwanted material or for controlling the particle size distribution of a sample, using a screen such as a woven mesh or net or perforated sheet material. The word ''sift'' derives from ''sieve''. In cooking, a sifter is used to separate and break up clumps in dry ingredients such as flour, as well as to aerate and combine them. A strainer (see Colander), meanwhile, is a form of sieve used to separate suspended solids from a liquid by filtration. Industrial strainer Some industrial strainers available are simplex basket strainers, duplex basket strainers, T-strainers and Y-strainers. Simple basket strainers are used to protect valuable or sensitive equipment in systems that are meant to be shut down temporarily. Some commonly used strainers are bell mouth strainers, foot valve strainers, basket strainers. Most processing industries (mainly pharmaceutical, coatings and liquid food indu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofilter
Biofiltration is a pollution control technique using a bioreactor containing living material to capture and biologically degrade pollutants. Common uses include processing waste water, capturing harmful chemicals or silt from surface runoff, and microbiotic oxidation of contaminants in air. Industrial biofiltration can be classified as the process of utilizing biological oxidation to remove volatile organic compounds, odors, and hydrocarbons. Examples of biofiltration Examples of biofiltration include: * Bioswales, biostrips, biobags, bioscrubbers, Vermifilters and trickling filters * Constructed wetlands and natural wetlands * Slow sand filters * Treatment ponds * Green belts * Green walls * Riparian zones, riparian forests, bosques * Bivalve bioaccumulation Control of air pollution When applied to air filtration and purification, biofilters use microorganisms to remove air pollution. The air flows through a packed bed and the pollutant transfers into a thin biofilm on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Engineering
Chemical engineering is an engineering field which deals with the study of operation and design of chemical plants as well as methods of improving production. Chemical engineers develop economical commercial processes to convert raw materials into useful products. Chemical engineering uses principles of chemistry, physics, mathematics, biology, and economics to efficiently use, produce, design, transport and transform energy and materials. The work of chemical engineers can range from the utilization of nanotechnology and nanomaterials in the laboratory to large-scale industrial processes that convert chemicals, raw materials, living cells, microorganisms, and energy into useful forms and products. Chemical engineers are involved in many aspects of plant design and operation, including safety and hazard assessments, process design and analysis, modeling, control engineering, chemical reaction engineering, nuclear engineering, biological engineering, construction specification, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solution (chemistry)
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. If the attractive forces between the solvent and solute particles are greater than the attractive forces holding the solute particles together, the solvent particles pull the solute particles apart and surround them. These surrounded solute particles then move away from the solid solute and out into the solution. The mixing process of a solution happens at a scale where the effects of chemical polarity are involved, resulting in interactions that are specific to solvation. The solution usually has the state of the solvent when the solvent is the larger fraction of the mixture, as is commonly the case. One important parameter of a solution is the concentration, which is a measure of the amount of solute in a given amount of solution or solvent. The term "aqueous solution" is used when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents ( citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
