Analyzing the Impact of Air Products’ Innovative APX LNG Process Technology and

Air Products will supply its proprietary APX natural gas liquefaction process technology and equipment. This includes main cryogenic heat exchangers (MCHEs), subcooling heat exchangers, and Rotoflow turbomachinery companders.

The MCHE and SCHE will be designed, engineered and manufactured at Air Products’ LNG equipment facility in Port Manatee, Florida. This is the same manufacturing location where we have built more than 75 LNG heat exchangers over four decades.

The AP-X Process Cycle

The heart of an LNG plant is its liquefaction process, which transforms natural gas into liquid form. This allows it to be transported by sea for economical distribution around the world. However, this transformation process destroys large amounts of potential energy that can be retrieved and used for electricity.

Air Products has developed an advanced liquefaction technology, called AP-X, to increase the efficiency of the compressors that liquefy the LNG. It uses a new, multi-stream exchanger design and other modifications to reduce energy losses, while increasing polytropic efficiency of the compressors.

The AP-X technology is being deployed at the Qatargas 2-Train 4 LNG facility in Ras Laffan Industrial City, Qatar. The liquefaction train is rated for an annual LNG production capacity of 7.8 million tonnes per year, and includes three wellhead platforms with 11 wells each, as well as an onshore gas processing terminal and a fleet of 14 Q-Flex tankers. It also uses two subsea pipelines shared with the adjacent Qatargas 3-Train 5 LNG facility.

The AP-X Equipment

Air Products provides key equipment and technology for 12 of the 14 LNG trains currently in operation at Qatargas’ Ras Laffan facility, including the initial units that started up in 1996 using AP-C3MRTM LNG process technology; six AP-X LNG Process units that started up between 2009 and 2011; and two new AP-X LNG Process units that are under construction for the North Field South (NFS) project. The company’s liquefaction equipment includes main cryogenic heat exchangers, subcooling heat exchangers, Rotoflow turbomachinery companders and nitrogen economizer cold boxes.

The AP-X equipment uses the proven, patented AP-X liquefaction cycle that improves upon earlier cooled mixed refrigerant processes by subcooling the LNG with a simple and efficient nitrogen expander loop. This enables greater capacity, improved energy efficiency and operational flexibility over a wide range of production capacities.

The liquefaction equipment is engineered and built at Air Products’ world-class Port Manatee, Florida, manufacturing facility. This state-of-the-art facility opened in January 2014 and completed a 60% expansion in October 2019 to meet the needs of an ever-expanding LNG industry.

The AP-X Technical Services

The design and production of LNG plants is driven by business objectives such as producing a maximum number of cargoes, meeting delivery schedules and operating within specific product specifications. Failure to meet these objectives can result in off-specification products and heavy penalties. Managing the plant to achieve these objectives requires close control of the process, equipment and operation.

Air Products’ AP-X technology is well suited to this type of management as the process uses an improved liquefaction cycle that subcools with a simple nitrogen expander loop, rather than a more complex mixture of refrigerants. This allows significantly higher capacity to be achieved.

Combined with an execution strategy maximising standard vendor packages and modular construction, the AP-X process offers a low target plant cost that can compete with other LNG liquefaction technologies for a small train capacity. The technology also offers high energy efficiency and can operate at a wide range of production capacities.

The AP-X Project

Air Products’ LNG process technology is at the heart of an LNG production plant, processing and cryogenically liquefying natural gas so that it can be shipped economically to meet the world’s energy needs. The company’s proprietary coil wound main LNG heat exchangers are used to liquefy the gas and also are responsible for producing vapor and liquid refrigeration to maintain the integrity of the LNG during transport.

The company’s equipment and technology is key to Qatar Petroleum’s massive liquefied natural gas (LNG) production expansion project, commonly known as the North Field East Project, in Ras Laffan, Qatar. Air Products is supplying its AP-X LNG Process technology and equipment for two of the four trains being fabricated for NFE that will deliver significantly higher LNG production.

The company has supplied key technology and equipment to all 14 existing Qatari LNG trains operating in Ras Laffan, including the initial units which started production in 1996 with Air Products’ AP-C3MRTM LNG technology; six AP-X LNG Process trains that started up between 2009 and 2011; and two AP-X LNG Process trains being fabricated for NFE. This totals over 82% of the world’s nameplate capacity for LNG production using this technology.