Enhanced precipitation efficiency of electrostatic precipitators by means of impulse energization

To assess the benefits of impulse energization with different coals, experimental industrial research was performed at a 70 MWe thermal power plant. Two technologies for impulse power supplies were tested over 10000 h of operation. The results of the tests, performed according to ASME standards, demonstrated that impulse energization has great advantages over conventional energization and ensures a collection efficiency from 99.6 to 99.9%, corresponding to emission levels below 50 mg/Nm/sup 3/, with a reduction in absorbed power from about 0.5 to about 0.1 Wh/Nm/sup 3/. Tests showed that with impulse energization there was a considerable decrease both in solid particulate emissions (about 90%) and in energy consumption (about 80%), as compared with conventional (AC rectified voltage) energization. Almost the same improvement was obtained when the flow rate in the experimental channel was increased to 1.8 times the nominal value, thus indicating low sensitivity to gas velocity variations. Thus, the suitability of the technology for complying with the targets set by environmental regulations, even in the presence of difficult solid particulate, was proved.<
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