A method for operating an air separation plant having a distillation column system, a heat exchanger, and an adsorber, wherein, in a first time period, a first operating mode is carried out and, in a second time period following the first time period, a second operating mode is carried out. In a third time period between the second time period and the first time period, a third operating mode is carried out, in which third operating mode compressed air is at least partially freed of water and carbon dioxide in the adsorber and at least part of said compressed air is cooled in the heat exchanger, an air product is removed from the distillation column system and at least part of said air product is heated in the heat exchanger.

A method for operating a heat exchanger, in which a first operating mode is carried out in first time periods, and a second operating mode is carried out in second time periods that alternate with the first time periods; in the first operating mode a first fluid flow is formed at a first temperature level, is fed into the heat exchanger in a first region at the first temperature level, and is partially or completely cooled in the heat exchanger; in the first operating mode a second fluid flow is formed at a second temperature level, is fed into the heat exchanger in a second region at the second temperature level, and is partially or completely heated in the heat exchanger. A corresponding arrangement and a system with such an arrangement are also covered by the present invention.

This specification relates to operating industrial facilities, for example, crude oil refining facilities or other industrial facilities that include operating plants that process natural gas or recover natural gas liquids.

A method for controlling a coupled heat exchanger system having a first heat exchanger block and a second heat exchanger block. A first fluid stream is divided into a first partial current and a second partial current both flowing through the heat exchanger system. A second fluid stream flows through the first heat exchanger block counter to the first partial current. A third fluid stream flows through the second heat exchanger block counter to the second partial current. An intermediate temperature is measured on one of the heat exchanger blocks. The amount of the first partial current and the second partial current is controlled based on the current value of the intermediate temperature. This control reduces the strain on the heat exchangers by changing loads while keeping fluctuations of the intermediate temperature low.

This specification relates to operating industrial facilities, for example, crude oil refining facilities or other industrial facilities that include operating plants that process natural gas or recover natural gas liquids.

This specification relates to operating industrial facilities, for example, crude oil refining facilities or other industrial facilities that include operating plants that process natural gas or recover natural gas liquids.

Enhancements to a dual column, nitrogen producing cryogenic air separation unit with waste expansion are provided. Such enhancements include an improved air separation unit arrangement that uses: (i) three condenser-reboilers; (ii) a reverse reflux stream from the condenser-reboiler associated with the lower pressure column to the higher pressure column; (iii) a waste expansion cycle, and (iv) a recycle stream of a portion of the boil off vapor from one or more of the condenser-reboilers. The improved air separation cycle minimizes the backpressure of the lower pressure column and yields improvements in the nitrogen recovery as well as reductions in unit power consumption compared to conventional dual column, nitrogen producing cryogenic air separation units employing waste expansion.

This specification relates to operating industrial facilities, for example, crude oil refining facilities or other industrial facilities that include operating plants that process natural gas or recover natural gas liquids.

This specification relates to operating industrial facilities, for example, crude oil refining facilities or other industrial facilities that include operating plants that process natural gas or recover natural gas liquids.

A method for operating a heat exchanger, in which a first operating mode is carried out in first time periods, and a second operating mode is carried out in second time periods that alternate with the first time periods; in the first operating mode a first fluid flow is formed at a first temperature, is fed into the heat exchanger in a first region at the first temperature, and is partially or completely cooled in the heat exchanger; in the first operating mode a second fluid flow is formed at a second temperature, is fed into the heat exchanger in a second region at the second temperature, and is partially or completely heated in the heat exchanger; and in the second operating mode the feeding of the first fluid flow and of the second fluid flow into the heat exchanger is partially or completely halted.