2009 Volume 2 Issue 1 Pages 27-32
In the chemical industry, there have been numerous reports on mechanical damage, such as pinholes, due to electrostatic discharge on the wall of glass-lined (GL) chemical vessels, in which slurries containing low-conductive liquid and low-soluble powder undergo vigorous stirring. To address this problem, we have developed an easy-to-operate, desktop electric field measuring system for predicting the charge generation in a GL vessel containing a slurry. This system includes a two-liter stirring vessel of glass covered with metal foil provided with electrostatic field sensors. Many combinations of solvent and powder were tested using this system. The electric field strengths on the wall of the testing vessel depended on the behavior and the conductivity of the slurries, the powder solubility, the stirrer revolutions, etc. The typical distribution and trends of electric fields during stirring were discovered. A practical screening method to identify potentially hazardous slurries in advance using our apparatus is proposed.
