Batch lost through bad design
A reaction was being carried out at 80°C. The boiling point of this
mixture was 90°C.
A runaway reaction ensued causing the temperature to rise to the boiling point, followed by a massive boil up rate and the batch was lost.
Investigations disclosed that the known adiabatic temperature rise for this reaction was 70°C. The designers did not take into account that the reaction would already be at 80°C when the reaction started, thus giving an expected theory final temperature of 150°C, some 60°C above the boiling point.
When specifying an adiabatic temperaure rise, one should always try to emphasize that it is a temperature rise, and not a final temperature.