Temperatures, industrial electrostatic precipitation

The results of Fig. 2.7 indicate that a significant fraction of particles in the nanometer size range will escape from electrostatic precipitator. for /i/oot values of the order of 10 ion sec cm . Such particles tend to form in high-temperature processes such as coal combustion, incineration, and the smelting of ores. Data are lacking on nanoparticle emissions from industrial electrostatic precipitators treating gases from coal-fired power plants or smelters. 

A semi-industrial pilot plant has been developed in which air-borne ultrasound has been applied to the reduction of particle emissions in coal combustion fumes [62]. The installation basically consists of an acoustic agglomeration chamber with a rectangular cross-section, driven by four high-power and highly directional acoustic transducers operating at 10 and/or 20 kHz, and an electrostatic precipitator (ESP). In the experiments, a fluidised bed coal combustor was used as fume generator with fume flow rates up to about 2000 m /h, gas temperatures of about 150 °C. and mass concentrations in the range 1-5 gm. The acoustic filter reduced fine particle emissions by about 40 %. 

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