Premises of evaluation of the filtration efficiency of an electrostatic precipitator by measuring of the electric charge

Most particle counters of dust or smoke particles have a higher sensitivity than other detection systems and provide more information at least indicative of the filtering efficiency in the case of an electrostatic precipitator for example. This allows the intervention by the activation of automatic control systems for increasing the performance. But the major drawback of these detectors is their high price and bulky installation in filtration systems. These detectors are particularly difficult to install and maintain. The objective of this paper is to propose a filtration efficiency evaluation technique based on the measurement of the electric charge. The latter is measured by means of a Faraday cages placed downstream of the ESP. The first Faraday pail is connected to a sensitive electrometer and controlled by a virtual instrument for data acquisition and processing, for measuring the electric charge unfiltered particles when passing through the Faraday cage. The second proposed method for assessing the ESP performance is based on an indirect charge measurement, corresponding to the corona discharge current following through the Faraday cage. Obtained results show significant concordance between the measured charge and the filtration efficiency.