System and method for supplying backup production in air separation device

A method for supplying a backup product from a backup system of an air separation apparatus, the method comprising the steps of:

• providing the backup system, wherein the backup system comprises:
• i. a storage tank configured to store a cryogenic liquid product, the storage tank having a lower region, a middle region, and an upper region;
• ii. a cryogenic liquid pump in fluid communication with an outlet of the storage tank that is in the lower region of the storage tank, wherein the cryogenic liquid pump is speed adjustable and is also configured to pressurize the cryogenic liquid product sent out from the storage tank to form a pressurized product fluid;
• iii. a delivery pipeline in fluid communication with an outlet of the cryogenic liquid pump, the delivery pipeline having a liquid pump outlet control valve disposed thereon that is configured to control a flow of a pressurized product fluid;
• iv. a first product supply line disposed downstream of the liquid pump outlet control valve and in fluid communication with the delivery pipeline, wherein the first product supply line is configured to have an operating pressure at a first pressure;
• and
• v. a second product supply line disposed downstream of the liquid pump outlet control valve and in fluid communication with the delivery pipeline, wherein the second product supply line is configured to have an operating pressure at a second pressure, wherein the first pressure is lower than the second pressure;
• extracting the cryogenic liquid product from the storage tank;
• vaporizing at least a portion of the cryogenic liquid product in a vaporizer to form a gaseous product;
• determining whether to operate in a normal operating state or a temporary operating state,
• wherein the normal operating state comprises the steps of:
• operating the cryogenic liquid pump in a cold standby state, wherein the cold standby state includes a cold standby flow rate and a cold standby operating pressure;
• and
• sending the gaseous product to only the first product supply line at the first pressure such that no gaseous product is sent to the second product supply line during the cold standby state;
• wherein the temporary operating state comprises the steps of:
• operating the cryogenic liquid pump in a backup state, wherein the backup state includes a backup flow rate and a backup operating pressure, wherein the backup operating pressure is higher than the cold standby operating pressure;
• and
• sending the gaseous product to the second product supply line at the second pressure.