Process and device for obtaining a compressed product by low temperature separation of air

An apparatus for obtaining a compressed product (22;

• 336) by low temperature separation of air, comprising:
• a. a rectification system which has a pressure column (3) and a low pressure column (4)
• b. a first feedstock air line (1, 50, 51, 677) for feeding compressed and purified feedstock air via a main heat exchanger system (2;
• 102a, 102b) into the pressure column (3),
• c. a liquid transfer line (5) for feeding a fraction from the pressure column (3) into the low pressure column (4), the liquid transfer line having an expansion means (7),
• d. means (25;
• 220) for increasing the pressure of an oxygen-rich fraction (24;
• 218a) removed from the low pressure column (4) with an outlet which is flow-connected (26;
• 218b, 224, 226) to the mixing column (27),
• e. a supply line (66) for feeding the heat exchange medium into the lower area of a the mixing column (27),
• f. a top product line (28) for removing the gaseous top product from the upper area of the mixing column (27), and
• g. means (20;
• 220;
• 337) for increasing the pressure of a liquid product fraction (19;
• 218a;
• 335) removed from the rectification system with an outlet which is flow-connected to the product evaporator (2, 102b), which is also connected to the top product line (28) and to a compressed product line (22;
• 336)
• wherein
• the product evaporator is formed by the main heat exchanger system (2;
• 102a, 102b) which provides indirect heat exchange between the liquid fraction (19) and the gaseous top product to vaporize the liquid product fraction (19).