Cooling Electrostatic

Langmuir Probe. A water-cooled electrostatic probe was constructed from several telescoping brass tubes around a 0.124 cm i.d. stainless steel tube containing a Pt/10% Rh probe wire insulated by fine quartz and Teflon sleeves. The probe wire, usually 0.025 cm diam, protruded 0.1 to 1.0 cm from the end of the tubes exposed to the flame gases. This probe assembly is referred to as the "fixed probe." A similar assembly was also used in which the Pt/... 

The gas, along with entrained ash and char particles, which are subjected to further gasification in the large space above the fluid bed, exit the gasifier at 954—1010°C. The hot gas is passed through a waste-heat boiler to recover the sensible heat, and then through a dry cyclone. SoHd particles are removed in both units. The gas is further cooled and cleaned by wet scmbbing, and if required, an electrostatic precipitator is included in the gas-treatment stream. 

Cooled dust-laden gas is dedusted in an electrostatic precipitator and sent to the cleaning unit to remove impurities such as arsenic, fluorine, and chlorine before being sent on to the sulfuric acid production plant. 

The gaseous ammonia is passed through electrostatic precipitators for particulate removal and mixed with the cooled gas stream. The combined stream flows to the ammonia absorber where the ammonia is recovered by reaction with a dilute solution of sulfuric acid to form ammonium sulfate. Ammonium sulfate precipitates as small crystals after the solution becomes saturated and is withdrawn as a slurry. The slurry is further processed in centrifuge faciHties for recovery. Crystal size can be increased by employing one of two processes (99), either low differential controUed crystallization or mechanical size enlargement by continuous compacting and granulation. 

After the SO converter has stabilized, the 6—7% SO gas stream can be further diluted with dry air, I, to provide the SO reaction gas at a prescribed concentration, ca 4 vol % for LAB sulfonation and ca 2.5% for alcohol ethoxylate sulfation. The molten sulfur is accurately measured and controlled by mass flow meters. The organic feedstock is also accurately controlled by mass flow meters and a variable speed-driven gear pump. The high velocity SO reaction gas and organic feedstock are introduced into the top of the sulfonation reactor,, in cocurrent downward flow where the reaction product and gas are separated in a cyclone separator, K, then pumped to a cooler, L, and circulated back into a quench cooling reservoir at the base of the reactor, unique to Chemithon concentric reactor systems. The gas stream from the cyclone separator, M, is sent to an electrostatic precipitator (ESP), N, which removes entrained acidic organics, and then sent to the packed tower, H, where SO2 and any SO traces are adsorbed in a dilute NaOH solution and finally vented, O. Even a 99% conversion of SO2 to SO contributes ca 500 ppm SO2 to the effluent gas. 

In general, plants using SO2 gas derived from metallic sulfides, spent acids, or gypsum anhydrite purify the gas stream before drying it by cold, ie, wet, gas purification. Various equipment combinations including humidification towers, reverse jet scmbbers, packed gas cooling towers, impingement tray columns and electrostatic precipitators are used to clean the gas. 

The use of nylon-11 for powder coatings or dry coatings (qv) has been developed in response to a growing concern for the environment (44) (see Coating PROCESSES, powder technology). Electrostatic deposition allows thin films to be appHed to metal substrates. Once the powder is appHed, it must be melted and coalesced into a continuous plastic film. Eorced draft or irradiant ovens are used for fusion, and because no polymerization or cross-linkage are required for curing, coated objects can be processed quickly and air-cooled (45). 

An electrostatic precipitator is used to remove more tar from coke oven gas. The tar is then sent to storage. Ammonia liquor is also separated from the tar decanter and sent to wastewater treatment after ammonia recovery. Coke oven gas is further cooled in a final cooler. Naphthalene is removed in a separator on the final cooler. Light oil is then removed from the coke oven gas and is fractionated to recover benzene, toluene, and xylene. Some facilities may include an onsite tar distillation unit. The Claus process is normally used to recover sulfur from coke oven gas. During the coke quenching, handling, and screening operation, coke breeze is produced. The breeze is either reused on site (e.g., in the sinter plant) or sold offsite as a by-product. 

The Electrical A nalogue of Magnetic Cooling. Three Processes bg Which Ions Are Introduced into Solution.. 1 Polar Dielectric in an Electrostatic Field. The Concepts of Faraday and Maxwell. The Electrostatic Energy in the Fields of Ions. The. Charging of a Condenser. The Amount of Free Energy Lost, by a Dielectric. The Behavior of Solvents in an Electrostatic Field. A Dielectric in the Field of a Charged Sphere. Two Types of Process Contrasted. 

Whether electrostatic technology is superior to magnetic device technology is debatable. What is of interest is that, in a 1998 marketing and technical support documentation pack from a major electrostatic unit manufacturer, most of the information supplied related primarily to cooling water applications rather than boilers. The boiler data, such as there was, concerned only smaller, simple systems (e.g., HW boilers and steam ovens). 

The coke oven is treated in the by-product plant to recover some important chemicals from it, after which the coke oven gas is used as gaseous fuel in the furnaces of steel plant. Coke oven gas is emitted at about 700 °C and is cooled to 80 °C with ammoniacal liquor (NH4OH) by spraying its goose neck. Here, the tar from the coke oven gas is condensed and separated in the separator. A further cooling of the gas to about 30 °C is accomplished in the primary cooler by water, and a further quantity of tar is condensed. The last traces of tar vapour present in the gas are removed in the next operation, which involves bringing the cooled gas to the electrostatic tar precipitator. This sends the tar-stripped gas to the... 

Another critical part of the incinerator design is the pollution control system.11 Pollution control systems directly influence the levels and kinds of pollutants that are released and that can potentially reach the public. Most modern hazardous waste incinerators are designed with extensive air pollution removal systems. For example, a common pollution control system might include a system that cools or quenches gases produced by burning waste, followed by a system that reduces acid gas emissions, and ultimately followed by a particulate removal system such as fabric filters (bag-houses), electrostatic precipitators, venturi scrubbers, and others.10... 

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