In the Bayer Crop Protection business group, we have developed a procedure to decide whether or not a mixing and milling facility is suitable to produce dry crop protection products in a safe manner.
Materials handled in such a facility may be combustible or thermally instable. The following hazards may exist: • A dust explosion may occur if a dust/air mixture is within explosion limits and an ignition source is present. • A dust/liquid aerosol hybrid mixture may be formed if flammable liquids are present. • An exothermal decomposition may occur generating pressure. Quick decomposition may lead to a heat explosion or the products of the decomposition may include flammable gases that eventually ignite and burn or explode.
Consequently, the following must be avoided to insure safety: • The start of decomposition reaction. • The explosion of a dust, gas or hybrid aerosol of flammable liquids and solids
The components and the formulated product need to be examined to determine under which conditions decomposition or explosion may occur.
A base set of material safety data is established following the German Guideline Test Methods to Determine the Safety Characteristics of Dusts (VDI 2263 Part 1).
Test methods are used to describe the undisturbed powder with respect to: • Flammability • Burning Behavior • Exothermic Decomposition • Deflagration • Impact Sensitivity
Additional test methods are used to describe the aerosolized powder • Dust Explosiveness • Minimum Ignition Energy
In a decision chart basic questions are answered with the help of these safety data to decide if a hazard is present during unit operations and which safeguards have to be taken. Additionally, one is able to decide whether or not a given facility is suitable to handle a specific product in a safe manner.