Process and plant for air separation by cryogenic distillation

摘要

Air is separated by cryogenic distillation in at least one column (2) to produce oxygen-rich liquid and nitrogen-rich vapour, heat exchanger (1) cooling the air (11) before it enters the column by heat exchange with an outgoing liquid fraction (23), which vapourises in exchanger (1). Cooling of column (2) is effected by a further feed of compressed fluid (13) which is depressurised in at least one turbine (9), the fluid in the turbine(s) being at least 95 and preferably 100% liquid. Also claimed is installation comprising the heat exchanger, distillation column and turbine.