To provide an internal heat exchanging type distillation column with superior uniformly liquid dispersing property to upper surface of a packed layer, stable gas flow in the column and causing little droplet entrainment.
In this internal heat exchanging type distillation column, operation temperature difference is caused by making operation pressures in a tube side 4 and shell side 5 different, heat is transferred from the high pressure side to the low pressure side through tube walls of tubes 25 serving as heat transfer surfaces, thereby high pressure side functions as an enriching section and the low pressure side functions as an exhausting section. When the shell side 5 is formed as a packed column, a column top vapor outlet 7 of the shell side 5 is disposed at a lower position than a column top liquid inlet 6, and liquid distributors 30 distributing liquid supplied from the liquid inlet 6 making it flow down on outer surfaces of the tubes 25, are disposed at a higher position than the vapor outlet 7.
ASO KAZUMASA
NAKANISHI TOSHINARI
NAT INST OF ADV IND & TECHNOL