Electrostatic precipitator emissions range

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 %. 

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. 

Air emissions from kilns arise because of the nature and chemistry of the raw material used and from the fuel burned in the kiln. Particulate emissions have traditionally been the main soimce of concern PM emissions generally range from 0.3-1.0 kg/tonne from the combined kiln and clinker cooling facilities. Electrostatic precipitators are commonly employed some humidification may be required to optimize moisture to maintain particle resistivity. Carbon monoxide levels in the ESP must be monitored to avoid explosive conditions. Some plants may also use fabric filter baghouses if flow conditions are appropriate and exhaust temperatures are not too high. Much of the collected kiln dust is often recirculated into the kiln feed. 

---