PROCESS FOR THE DELIVERY OF OXYGEN AT A VARIABLE RATE

摘要

A process delivers oxygen at a variable flow rate from a distillation system . The process uses a higher pressure column and a lower pressure column. The effects of oxygen product rate fluctuations on the distillation system are reduced by maintaining essentially constant flow rates within the columns. The process also utilizes a first storage vessel a nd a second storage vessel and includes the following features: liquid oxygen is withdrawn at a substantially constant rate from the distillation column system and at least a portion of the withdrawn liquid oxygen is directed to the second storage vessel; liquid oxygen is withdrawn from the second storage vessel at a variable rate and vaporized in a main heat exchanger against an incoming variable flow rate of air which is condensed to form a liquid air stream and then sent directly to the distillation column system; and liquid oxygen is withdrawn from the distillation column system from the same location where at least one of the liquid air streams i s fed to the distillation column system, and at least a portion of the liquid air is directed to the first storage vessel during periods of higher than average oxygen delivery rate.