Electrostatic precipitator plate

Industrial Solar collectors Electrostatic precipitator plates Fan blades Business machine cabinetry Water tanks... 

A unit is available in which electrostatic precipitation is combined with a dry-air filter of the type shown in Fig. 17-64Z . In another unit an electrostatic field is superimposed on an automatic filter. In this case the ionizer wires are located on the leading face of the unit, and the collecting electrodes consist of alternate stationary and rotating parallel plates. Cleaning in this case is automatic and continuous. 

Fig. 29-10. Wet ESP with plate collection electrodes. Source Oglesby, S., ]r., and Nichols, G. B., Electrostatic precipitators in "Air Pollution," 3rd ed., Vol. IV (A. C. Stem, ed.), p. 239, Academic Press, New York, 1977.

Continuous-spray, parallel-plate, wet electrostatic precipitators... 

The two-stage electrostatic precipitators used in light-industry applications are compact devices which can be fitted into the ventilation system. These air cleaners are normally used to clean air from dusts, smokes, and fumes in industrial workplaces. The basic features of these devices are the separate sections for particle charging and collection. The charging section consists of thin metal wires installed between grounded metal plates. The distance... 

Electrostatic precipitator A filtering system for the removal of particles from an air stream by giving them an electrical charge. The charged particles are attracted to plates of opposite polarity onto which they adhere. The precipitators are classified as... 

Very fine particles such as smokes can be caught by electrostatic precipitation. A high voltage is applied to plates or wires within the filter bank, to impart a static charge to dirt particles. These will then be attracted to earthed plates, and adhere to them. Impurities are generally cleaned off the plates by removing the stack and washing. 

Electrostatic precipitators are generally used to separate particulate matter that is easily ionized from a gas stream3,8,10. This is accomplished by an electrostatic field produced between wires or grids and collection plates by... 

A coal combustion pilot plant is used to obtain efficiency data on the collection of particulate matter by an electrostatics precipitator (ESP). The ESP performance is varied by changing the surface area of the collecting plates. Figure E2.2 shows the data collected to estimate the coefficients in a model to represent efficiency 17 as a function of the specific collection area A, measured as plate area/volumetric flow rate. 

Electrostatic precipitators devices used to trap fine dust particles (usually in the size range 30 to 60 p,m) that operate on the principle of imparting an electric charge to particles in an incoming airstream which are then collected on an oppositely charged plate across a high-voltage field. 

Wet electrostatic precipitators (WESP) are used for removal of liquid contaminants such as sulfuric acid mist, aerosols, and particulate matter. The acid mist and aerosols are typically formed in a WGS by condensation of SO3. Unlike dry precipitators, wet precipitators do not require rapping to remove the dust. The collected mist and particulate matter form a liquid film that runs down a vertical collecting plate. In some cases, a continuous spray of liquid is used to prevent solids deposition on the collecting plates. 

The particles in a flue gas can pick up an electric charge when they move through an electrical field. The operation of an electrostatic precipitator makes use of this property. After passing the flue gas through the field, the device exposes the charged particles to plates carrying the opposite charge, which attract them. The particles stick to the plates and are periodically scraped off for disposal. 

An example of a study in which this approach was applied involved the use of a transmission electron microscopy (TEM) grid as the collector plate in the electrostatic precipitator (Witkowski et a ., 1988). After sample collection, analysis by TEM (vide infra) could then be carried out. 

Fluid Electrode Precipitator. In general, the best way to remove fine dust from an air stream is to use conventional electrostatic precipitators. Although the efficiencies of these devices are quite high, there are inherent drawbacks that do not make them acceptable in continuously operating air systems. The collection plates eventually become saturated with the deposited... 

On my sulfuric acid production unit in Texas City, we had an electrostatic precipitator to remove a liquid sulfuric acid mist from a flowing gas stream. It worked in the same way as a precipitator in liquid-liquid service. However, the electrodes or grids were not parallel plates. As illustrated in Fig. 26.4, the grids were lead tubes and lead-coated wires. 

The collection efficiency of the wire-plate-type of electrostatic precipitator can be estimated by the widely used Deutsch theory [Deutsch, 1922]. To obtain the Deutsch equation, the following assumptions are made (1) because of the turbulent mixing effect, particle concentration at any cross section of the precipitator is uniformly distributed ... 

Consider a parallel-plate electrostatic precipitator across which a 10 kV potential is applied. The interplate spacing is 1 cm. The particle density is 2,000 kg/m3. The total surface area is 10 m2, and the flow rate is 0.5 m3/s. Use the test results provided in Table P7.2 to estimate... 

Fig. 4.3. Schematic of dry rod and plate electrostatic precipitator (after Oglesby and Nichols, 1978). The rods have sharp horizontal protrusions (nails) which promote corona formation. Dusty gas flows between the plates and around the rods. A large electrical potential (60 000 V) is applied between the rods and plates. This negatively charges the dust particles - causing them to approach and adhere to the positive collection plates. The dust is gathered by periodically rapping the plates, causing sheets of dust to fall into dust bins below, Fig. 4.4. Table 4.2 gives industrial precipitation data.

Fig. 4.4. Wire and plate dry electrostatic precipitator, reprinted from Oglesby and Nichols (1978), p 269 by courtesy of Taylor and Francis Group, LLC. The parallel collector plates and bottom dust bins are notable. In this case, wires are hung between the plates - weights for keeping them vertical are just visible. Structural and operating data for a recent precipitator are ...

---