Comparative analysis of two plate-to-plate electrode configurations for dust resistivity measurement

Dust resistivity is a key parameter in the efficiency of electrostatic precipitators, yet its measurement is influenced by numerous environmental and methodological factors. In this study, the specific resistivity of coal, biomass, and mixed-fuel-derived dust samples was investigated using two plate-to-plate electrode arrangements under controlled temperature and humidity conditions. Arrangement #1 used square electrodes and vibratory compaction, while Arrangement #2 used cylindrical electrodes with weight-based compaction and a guarding ring to reduce edge effects. Measurements were performed across six temperature levels (30–180 °C) in both heating and cooling cycles, revealing temperature- and humidity-dependent shifts from surface to bulk conduction mechanisms. Time-dependent resistivity profiles were recorded at fixed intervals to capture polarization effects. Results indicated that Arrangement #2 generally produced lower resistivity values, likely due to enhanced compaction and increased surface contact. The experiments also highlighted discrepancies in repeatability and compaction sensitivity between arrangements. These findings contribute to a deeper understanding of dust conduction mechanisms and inform the design of future measurement protocols. • Compaction and electrode configuration strongly influence resistivity measurements. • Results show porosity, layer thickness, and electrode pressure must be considered when comparing measurements across setups. • Above 10 g/cm², pressure hardly affects resistance in compacted samples, but uncompacted ones show larger deviations. • Vibratory compaction yields resistivity 5–10× higher than compression by electrode weight across different powders.