Chemical process safety has become a widespread, international concern and receives high attention within the chemical industry. To improve process safety awareness, we publish short introductions into different process safety issues in cooperation with the monthly one-page Process Safety Beacon of the Center for Chemical Process Safety (CCPS).
Third Topic: Incompatible Mixtures in Storage Tanks
The unintentional mixing of incompatible chemicals, for example, during raw material delivery and unload into storage tanks of a plant, can lead to reactions of these chemicals and the release of, e.g, a cloud of chlorine gas into the surrounding. Avoiding this includes checking of all documentation and labeling on incoming shipments, following plant procedures for identification and unloading of incoming raw materials, clear labeling of all piping and equipment in the raw material unload area, and avoiding confusing pipes. Incompatible materials also should not be unloaded near to each other.
Which mixtures might lead to a release of a chlorine gas cloud?
a) Sulfuric acid and sodium hypochlorite (bleach).
b) Phosphoric acid and sodium hypochlorite.
c) Hydrochloric acid and sodium hypochlorite.
d) Sodium hydroxide and sodium hypochlorite.