Laboratory analysis of back-corona discharge

An experimental research program was designed and performed to characterize back-corona generation and behaviour in a range of environments and geometries common to electrostatic precipitators (ESP's). A wire-parallel plate device was utilized to monitor the intensity and distribution of back-corona discharges. Back-corona was generated by subjecting a deposited layer of fly ash to corona current. Visual observations of back-corona emissions were made with a sensitive video camera. These observations provided new insight into the characteristics of back-corona phenomena. Conditions that were varied in the experiments included ash resistivity, corona electrode design, corona polarity, and ash-layer thickness and surface condition. The effect of pulsed energization on back-corona was also studied. Analyses of visual observations and measured distributions of corona- and back-corona current allowed an assessment of the effects of back-corona emissions on ESP-operating parameters.