Apparatus for the production of air gases by the cryogenic separation of air with variable liquid production and power usage

An apparatus for the production of air gases by the cryogenic separation of air, the apparatus comprising:

• a cold box configured to receive a purified and compressed air stream under conditions effective for cryogenically separating the air stream to form an air gas product using a system of columns, wherein the purified and compressed air stream is at a feed pressure PF when entering the cold box, wherein the air gas product is selected from the group consisting of oxygen, nitrogen, and combinations thereof, wherein the cold box is configured to produce the air gas product at a product pressure PPO, wherein the cold box is in fluid communication with an air gas pipeline, such that the apparatus, during operation, is configured to send an air gas product from the cold box to the air gas pipeline, wherein the system of columns comprises a double column comprised of a lower pressure column and a higher pressure column, wherein the cold box further comprises a main heat exchanger, a condenser disposed at a bottom portion of the lower pressure column, and a liquid oxygen pump configured to receive liquid oxygen from the system of columns and introduce the liquid oxygen to a cold end of the main heat exchanger;
• a main air compressor disposed upstream the cold box;
• a booster air compressor downstream the main air compressor and upstream the cold box;
• a pressure monitoring device configured to monitor the pipeline pressure PPL;
• and
• a controller configured to operate the apparatus in a first mode of operation and a second mode of operation, wherein the controller is further configured to adjust one or more pressure set points of the apparatus based on the monitored pipeline pressure, wherein the one or more pressure set points of the apparatus is selected from the group consisting of a discharge pressure of the booster air compressor, a discharge pressure of the main air compressor, a discharge pressure of the liquid oxygen pump, and combinations thereof,
• wherein the controller is further configured to receive liquid product data, wherein the liquid product data comprises spot pricing data for liquid oxygen,
• wherein during the first mode of operation, the controller is further configured to reduce the difference between the pipeline pressure PPL and the discharge pressure of the liquid oxygen pump,
• wherein during the second mode of operation, the controller is further configured to reduce the difference between the pipeline pressure PPL and the delivery pressure PDO;
• and adjust liquid production from the cold box.