Modern methods and devices for ensuring electrostatic safety at hazardous plants relating to high-energy materials are shown.
Special hazard is the processes of handling bulk substances: loading, unloading, grinding, feeding into transport bins, sifting devices, metering devices, etc. In connection with this, additional measures are required to ensure explosion prevention and protection of the process being implemented. Special attention is paid to dust-air mixtures of the circulating explosion and fire hazardous substances that are sensitive to ignition by static electricity discharges.
The process of static electricity charges discharge is identified mainly by the electrical properties of the circulating substances, the environment, and the materials from which the process equipment is made. The primary importance when calculating the relaxation time of the charge of static electricity from bulk substances is the experimental determination of the relative dielectric permeability of powders.
The results are given concerning calculation of time of discharging the accumulated electrostatic charge from high-energy materials. The causes of the occurrence and accumulation of electrostatic charges on high-energy substances and equipment, the conditions of electrostatic intrinsic safety of production, and, also the methods are shown related to the methods of identifying the electrostatic parameters of bulk materials.
Appropriateness of reducing the classification of bulk explosives according to the intervals of the values of the minimum ignition energy and the values of specific volume resistance to the international one is shown in the article.
The methods are proposed for calculating the relaxation time of the static electricity charge accumulated on loose dielectric explosion and fire hazardous substances, and the results of calculations are given.
The obtained values of minimum ignition energy of bulk substances find their application at the development of measures and means of ensuring electrostatic safety of the technological processes of explosion and fire hazardous plants.