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Introduction
Published in Amitava Sil, Saikat Maity, Industrial Power Systems, 2022
Electrostatic Precipitator, or ESP, is a particulate collection filtration device that removes particles or fly ash from the exhaust called flue gas using the force of an induced electrostatic charge. It is a filtration device. ESP collects fly ash and other solid suspended particles from exhaust gases of a coal-fired boiler furnace. The dust-laden flue gas is passed between the oppositely charged conductors and becomes ionized as the voltage applied between the conductors is sufficiently large (30–60 kV depending upon the electrode spacing). As the dust-laden gas is passed through the highly charged electrodes, both negative and positive ions are formed. The ionized gas is further passed through the collecting unit which consists of a set of metal plates. Alternate plates are charged and earthed. As the alternate plates are grounded, high intensity electrostatic field exerts a force on the positive charged dust particles and drives them toward the ground plate. The deposited dust particles are removed from the plates by rapping hammer (dry ESP), scraping brush (dry ESP) or flushing water (wet ESP).
Air pollution control and mitigation
Published in Abhishek Tiwary, Ian Williams, Air Pollution, 2018
The electrostatic precipitator (ESP) is widely used for collecting emissions from certain process industries – notably coal-fired power plants, cement kilns, pulp and paper mills, steel mills and incinerators. The ESP casing (Figure 9.3d) has a large cross-sectional area to slow the gas down (0.9–1.7 m s−1), establish laminar flow and give a long residence time. Within the casing, the gas flows between vertical parallel plates which are the positive electrodes. Sandwiched in alternate layers between the plates are vertical frames carrying wires, the negative electrodes, which are maintained at 20–100 kV. Uniform distribution of velocities over the cross-section is important, as collection efficiency depends on residence time.
Air pollutants
Published in Abhishek Tiwary, Jeremy Colls, Air Pollution, 2017
The electrostatic precipitator (ESP) is widely used for collecting emissions from certain process industries – notably coal-fired power plants, cement kilns, pulp and paper mills, steel mills and incinerators. The ESP casing (Figure 2.15(d)) has a large cross-sectional area to slow the gas down (0.9–1.7 m s–1), establish laminar flow and give a long residence time. Within the casing, the gas flows between vertical parallel plates which are the positive electrodes. Sandwiched in alternate layers between the plates are vertical frames carrying wires, the negative electrodes, which are maintained at 20–100 kV. Uniform distribution of velocities over the cross section is important, since collection efficiency depends on residence time. During its passage between the plates, the corona discharge between the electrodes imparts net negative charges to the particles, which then migrate to the positive plates under the influence of the electrostatic field. When a layer of particles has accumulated on the plates, it is knocked off (rapped) into collecting hoppers. The detailed theory of operation is very complex, involving the corona current, attachment of ions to particles of different diameters and electrical properties, and movement of the charged particles at their terminal speeds to the collecting plate. These processes can be summarised in the Deutsch equation, by which:
Performance evaluation of novel wet vibrational precipitator
Published in Journal of the Air & Waste Management Association, 2019
M. Ali, C. Hedrick, A. Lutfullaeva, K. Alam
With exponential industrial growth over the last few decades, air pollution control has emerged as a grave concern for mankind due to its harmful effects on human health and the environment. Electrostatic precipitators (ESPs) were developed as air pollution control systems operating in a variety of environments, such as coal-fired power plants, steel industry, paper mills, cement manufacturing, and many other industries. The very first commercial unit was built in 1907 by H Frederick Cottrell (White 1963). Since then, ESP has gone through several iterations to improve particulate capture efficiencies. The particulate capture efficiency of latest ESP systems can be above 99% (U.S. Environmental Protection Agency [EPA] 2018.;Chen et al. 2014).
Use of bluff body for enhancing submicron particle agglomeration in plasma field
Published in Particulate Science and Technology, 2018
Attakorn Asanakham, Tanongkiat Kiatsiriroat
Electrostatic precipitator (ESP) effectively precipitates small particles in exhaust gas. However, its efficiency drops to be less than 50% for very fine particles smaller than PM 2.5 (Ito et al. 1995). Around 15% of these submicron particles can float away to the atmosphere (Mohr et al. 1996). Ultrafine particles, from less than 0.01 µm to more than 50 µm in diameter, are easily deposited in the lungs (Jimoda 2012), where they can cause diseases related to the human respiratory system (Politis, Pilinis, and Lekkas 2008). Given the health dangers, considerable research has focused on increasing the collection efficiency.
Novel electrostatic induction measurement method for monitoring particle flows in an electrostatic precipitator
Published in Particulate Science and Technology, 2020
Djillali Aouimeur, Farid Miloua, Malika Bengrit, Fatiha Tounsi, Amar Tilmatine
Electrostatic precipitation is widely used to remove pollution causing solid particles (such as dust and ashes) and liquids (e.g., oil mist) contained in the gases emitted by industries into the atmosphere (White 1963; Mizuno 2000; Remaoun et al. 2014). Due to the low power consumption and high filtration efficiency, electrostatic precipitators (ESPs) are employed in power plants, cement factories, machinery rooms such as in wood or in metal industries, offices and residential buildings, hospital, etc. (Miloua et al. 2013).