Experimental Study on Electrostatic Precipitation of Low-Resistivity High-Carbon Fly Ash at High Temperature

Abstract

A high-temperature electrostatic precipitator (ESP) is a good solution for hot gas cleaning to ensure the long-term stability of the production system in many energy-consuming industries. The high-carbon fly ash particles in the gasification of coal pyrolysis process are typical particles with low resistivity. In this paper, the characteristics of the coal pyrolysis furnace fly ash (ash A) were compared with coal-fired power plant fly ash (ash B). The effects of their characteristics on particle removal were compared in a wire-plate ESP. The particle collection efficiency was found to decrease with increasing temperature. From 363 to 523 K, the collection efficiencies of both ash samples were as high as above 95%. However, at 623 and 723 K, the collection efficiency of ash A was obviously lower than ash B. A method of enhancing particle removal was proposed by particle conditioning to reduce the occurrence of particle re-entrainment, and the fine calcium carbonate powders were used as the conditioning particles to improve the collection efficiency. When the ratio in mass was 1:1, the particle collection efficiency of ash A increased from 93.5% to 99.2% at 623 K by particle conditioning in the ESP. The optimal effect of conditioning occurred compared with different mix proportion because the resistivity of mixing particles was 1.01 × 10 8 Ω•cm, within the scope of normal resistivity for good operation of ESP.

Overview of Electric Field Applications in Energy and Process Engineering

“…Furthermore, they are recently applied for PM reduction in the exhaust gas of diesel engines [77], for small-scale biomass furnaces [78], in coal pyrolysis furnaces and coal-fired power plants to reduce fly ash [79], etc. In Ref.…”

How critical is geometrical confinement? Analysis of spatially and temporally resolved particulate matter removal with an electrostatic precipitator

“…A constant 10 cm s À1 air ow is chosen because it is a typical condition chosen in the literatures. 23,48,49 For both modes, the spatial and temporal dispersions of PM are monitored using a home-made laser light scattering setup, as described below.…”

A New Angular Light Scattering Measurement of Particulate Matter Mass Concentration for Homogeneous Spherical Particles

“…Air pollution has become one of the most serious environmental issues in China, especially particulate matter pollution. The particulate matter emitted by coal-fired power plants is one of the main pollution sources [1,2,3,4,5,6]. Currently, with the increasingly rigorous emission standards [7], the accuracy of real-time measurement of particulate matter mass concentrations should be improved urgently.…”

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