|
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Aerosol pollution over Northern India and Bangladesh - Photo: NASA Particulates, alternatively referred to as particulate matter (PM), aerosols or fine particles, are tiny particles of solid (a smoke) or liquid (an aerosol) suspended in a gas. ...
Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interactions. ...
Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In chemistry, alchemy and water treatment, filtration is the process of using a filter to mechanically separate a mixture. ...
Invention of the electrostatic precipitator
In 1907 Dr. Frederick G. Cottrell applied for a patent on a device for charging particles and then collecting them through electrostatic attraction — the first electrostatic precipitator. He was then a professor of chemistry at the University of California, Berkeley. Cottrell first applied the device to the collection of sulfuric acid mist emitted from various acid-making and smelting activities. 1907 (MCMVII) was a common year starting on Tuesday (see link for calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ...
Frederick Gardner Cottrell (1877-1948) was an American physical chemist and inventor. ...
Electrostatics is the branch of physics that deals with the force exerted by a static (i. ...
The University of California, Berkeley (also known as UC Berkeley, Berkeley, Cal, and by other names, see below) is the oldest and flagship campus of the ten-campus University of California system. ...
Sulfuric acid (British English: sulphuric acid), H2SO4, is a strong mineral acid. ...
Cottrell recognized the business potential of his invention and decided to use that to fund scientific research through the creation of a foundation called Research Corporation in 1912 to which he assigned the patents. Research Corporation has provided vital funding to many scientific projects: Goddard's rocketry experiments, Lawrence's cyclotron, production methods for vitamins A and B1, among many others. The organization continues to be active to this day. 1912 (MCMXII) was a leap year starting on Monday in the Gregorian calendar (or a leap year starting on Tuesday in the 13-day-slower Julian calendar). ...
Robert Goddard Robert Hutchings Goddard born in a brown home on the east side of town. ...
Ernest O. Lawrence Ernest Orlando Lawrence (August 8, 1901 – August 27, 1958) was an American physicist and Nobel Laureate best known for his invention, utilization, and improvement of the cyclotron beginning in 1929, and his later work in uranium-isotope separation in the Manhattan Project. ...
A pair of Dee electrodes with loops of coolant pipes on their surface at the Lawrence Hall of Science. ...
Retinol, the dietary form of vitamin A, is a fat-soluble, antioxidant vitamin important in vision and bone growth. ...
Thiamine mononitrate Thiamine or thiamin, also known as vitamin B1, is a colorless compound with chemical formula C12H17ClN4OS. It is soluble in water and insoluble in alcohol. ...
The plate precipitator The most basic precipitator contains a row of thin wires, and followed by a stack of large flat metal plates, with the plates typically spaced about 1 cm apart. The air stream flows through the spaces between the wires, and then passes through the stack of plates.
A negative voltage of several thousand volts is applied betwen wire and plates. If the applied voltage is high enough an electric discharge ionize the air around the electrodes. Negative ions flows to the plates and charge the gas-flow particles. Josephson junction array chip developed by NIST as a standard volt. ...
The ionized particles, following the negative electric field created by the power supply, move to the grounded plates.
Particles buildup on the collection plates and forms a layer. The layer do not collapse, thanks to electrostatic pressure (given from layer resistivity, electric field and current flowing in the collected layer).
Modern industrial electrostatic precipitators ESPs continue to be excellent devices for control of many industrial particulate emissions, including smoke from electric generating utilities (coal and oil fired), salt cake collection from black liquor boilers in pulp mills, catalyst collection from fluidized bed catalytic cracker units in oil refineries to name a few. These devices treat gas volumes from several hundred thousand ACFM to 2.5 million ACFM in the largest coal-fired boiler applications. Brief Black liquor is a recycled byproduct formed during the chemical pulping of wood in the papermaking industry. ...
When manufacturers list performance for blowers and compressors it is stated as Capacity in CFM (Cubic Feet per Minute). ...
The original parallel plate – weighted wire design (described above) has evolved as more efficient (and robust) discharge electrode designs were developed, today focusing on rigid discharge electrodes to which many sharpened spikes are attached, maximizing corona production. Transformer-rectifier systems apply voltages of 50-100 kilovolts at relatively high current densities. Modern controls minimize sparking and prevent arcing, avoiding damage to the components. Automatic rapping systems and hopper evacuation systems remove the collected particulate matter while on line, allowing ESPs to stay in operation for years at a time. In electricity, a corona discharge is an electrical discharge brought on by the ionization of a fluid surrounding a conductor, which occurs when the potential gradient exceeds a certain value, in situations where sparking (also known as arcing) is not favoured. ...
Josephson junction array chip developed by NIST as a standard volt. ...
Wet electrostatic precipitator Electrostatic precipitation is typically a dry process, but spraying moisture to the incoming air flow helps collect the exceptionally fine particulates, and helps reduce the electrical resistance of the incoming dry material to make the process more effective.
A wet electrostatic precipitator (WESP) merges the operational methods of a wet scrubber with an electrostatic precipitator to make a self-washing, self-cleaning yet still high-voltage device. The word scrubber can mean:- The part of a rebreather breathing set which absorbs the carbon dioxide which the individual using the breathing set breathes out. ...
Consumer-oriented electrostatic air cleaners Plate precipitators are commonly marketed to the public as air purifier devices (such as the much-hyped Ionic Breeze) or as a permanent replacement for furnace filters, but all have the undesirable attribute of being somewhat messy to clean. A negative side-effect of electrostatic precipitation devices is the production of toxic ozone and NOx. However, electrostatic precipitators offer benefits over other air purifications technologies, such as HEPA filtration, which require expensive filters and can become "production sinks" for many harmful forms of bacteria. A Sharp FU-888SV Plasmacluster air purifier. ...
An air purifier is a device which aims to free air from contaminants. ...
For other uses, see Ozone (disambiguation). ...
There are several possible use of the 3 letter word/formula nox: Nox is a goddess of Night: see Nyx. ...
HEPA (IPA: ) is an acronym for high efficiency particulate absorbing or high efficiency particulate arrestance or, as officially defined by the Department of Energy (DOE) high efficiency particulate air. This type of air filter can theoretically remove at least 99. ...
With electrostatic precipitators, if the collection plates are allowed to accumulate large amounts of particulate matter, the particles often bond so tightly to the metal plates that vigorous washing and scrubbing may be required to completely clean the collection plates. The close spacing of the plates can make thorough cleaning difficult, and the stack of plates often cannot be easily disassembled for cleaning.
Some consumer precipitation filters are sold with special soak-off cleaners, where the entire plate array is removed from the precipitator and soaked in a large container overnight, to help loosen the tightly bonded particulates.
See also The word scrubber can mean:- The part of a rebreather breathing set which absorbs the carbon dioxide which the individual using the breathing set breathes out. ...
An air ioniser is a device which uses high voltage to ionize, or electrically charge, molecules of air. ...
An ozone generator is a device which generates ozone molecules for dispersion into air, water, or both for various applications. ...
External links - How an Electrostatic Precipitator Works
- Electrostatic Precipitators for Power Plants
| 
Feeds |
Contact