Study on the evaluation method of spray electrification hazards using a small amount of liquid sample

Abstract

Previous studies on spray electrification have shown that the amount of charging strongly depends on the combination of the liquid type and nozzle material. To prevent accidents, understanding, in advance, the charging hazards of each combination of liquid type and nozzle material, avoiding combinations that increase the charging, and taking sufficient safety measures according to the charging hazards are necessary. Predicting the hazard from the combination of liquid type and nozzle material is difficult with conventional knowledge. In this study, we proposed a simple method to evaluate the risk of spray electrification for various combinations and investigated the usefulness of the proposed method by measuring the charge for eight different liquids and three different materials. Consequently, clear differences were observed in the measured charges for each combination, and the charging characteristics shown in this study were in agreement with those in previous findings on spray electrification. Furthermore, except for certain combinations, the measured values obtained in this study were equal to or higher than those in the previous studies. Therefore, the proposed method reproduces spray electrification and is useful for hazard assessment.