Cryogenic air separation unit (ASU)

Hangyang Co., Ltd. (SH: 002430; Hangzhou, Zhejiang; ~¥11B revenue 2023) is China's largest and the world's fourth-largest cryogenic ASU manufacturer. Founded 1950 as a state-owned enterprise in Hangzhou; produces ASUs ranging from small medical oxygen units to very large plants (60,000+ Nm³/h oxygen). China's massive steel industry (producing ~57% of global crude steel) drove Hangyang's scale-up over 2000-2020. Hangyang is now a competitive global ASU supplier bidding against Linde and Air Liquide in developing markets (Southeast Asia, Middle East, Africa). Also manufactures LNG cold boxes and gas storage equipment. Listed on Shenzhen Stock Exchange. Increasingly cited as a competitive threat in markets where Western ASU OEMs face sanctions or cost pressure.

Linde Engineering (part of Linde plc; NYSE/FRA: LIN; Dublin, Ireland; HQ Pullach Germany for engineering division; ~$34B revenue) designs and delivers small-scale LNG liquefaction plants using Linde's proprietary LIMUM (Linde Mixed reFrigerant Updated Modular) and other natural gas liquefaction cycles. Linde Engineering has built multiple LNG peak-shaving plants and distributed LNG liquefaction facilities in the US and Europe. Linde is one of just three technology licensors (with Air Products and Shell SEAP) that control the majority of global LNG process technology. Linde Engineering's LNG reference list includes utility peak-shaving plants in the US Northeast and Europe, and LNG satellite and virtual pipeline systems.

Air Liquide S.A. (Euronext: AI; Paris; ~€27B revenue 2024) is the world's second-largest industrial gas company. Air Liquide Engineering & Construction (AL E&C) is the in-house ASU design/build division. Subsidiary ALD (Air Liquide Deutschland) and other regional subsidiaries build and operate ASUs globally. AL operates ~900 air separation units across its own gas production network. Alongside Linde, the dominant Western ASU engineering contractor. AL's Sassenage, France engineering center is the primary R&D site for cryogenic process design. Air Liquide has operated in industrial gases since its founding in Paris in 1902.

Linde plc (NYSE/FWB: LIN; HQ Dublin, Ireland; operational HQ Guildford UK; ~$32B revenue 2023) is the world's largest industrial gas company. Linde owns and operates one of the two largest liquid oxygen cryogenic tanker fleets globally — thousands of vacuum-insulated trailers delivering LOX to hospitals, steel mills, chemical plants, and semiconductor fabs in 80+ countries. Linde does not primarily manufacture its own tankers (purchases from Chart Industries and other OEMs) but specifies custom vacuum-insulated designs for its fleet. Linde's medical oxygen business (hospital LOX supply) is the dominant fleet use case. Linde also supplies liquid oxygen rocket propellant to aerospace customers including NASA and commercial launch operators.

World's largest industrial gas company; provides gas odorant distribution and blending services globally including ethyl mercaptan. Air Liquide distributes and markets mercaptan gas odorants to LPG and natural gas utilities. Also a leading producer of industrial gases (oxygen, nitrogen, hydrogen, noble gases) for healthcare, industry, and energy. Air Liquide is listed among the top ethyl mercaptan market participants; primarily as a specialty gas blender/distributor rather than a primary mercaptan chemical producer.

Air Products and Chemicals (NYSE: APD; Allentown, PA; ~$12B revenue) licenses the APCI (Air Products and Chemicals, Inc.) natural gas liquefaction process technology used in many small- and mid-scale LNG liquefaction trains worldwide, including utility peak-shaving plants. The APCI propane pre-cooled mixed refrigerant (C3MR) process dominates large baseload LNG export trains globally (used in >90% of world's baseload LNG capacity), but Air Products also licenses adapted cycles for smaller peak-shaving applications. Air Products competes with Linde Engineering for small-scale liquefaction process technology licensing. Air Products is also the world's largest industrial gas producer, supplying nitrogen and other gases used in LNG facility construction and purging.

Chart Industries (NYSE: GTLS; Ball Ground, GA; ~$4B revenue post-Howden) is the world's dominant manufacturer of cryogenic equipment for LNG, including peak-shaving plant liquefiers, brazed aluminum heat exchangers (BAHX), cold boxes, storage tanks, and LNG vaporizers. Chart's Industrial & Commercial Energy (ICE) division is the primary vendor for utility LNG peak-shaving plant equipment in North America. Chart acquired Howden (Glasgow-based industrial compressor and fan manufacturer) in 2023 for $4.4B, adding compression technology to its cryogenic heat exchanger and storage portfolio — making Chart a near-complete LNG equipment systems integrator. Chart also produces the CAIRE/MVE biomedical cryogenic cylinders and acquired La Crosse Cooler and other brands. The La Crosse, WI cryogenic division manufactures vacuum-insulated storage vessels. Chart is the single most critical equipment supplier for US utility LNG peak-shaving — if a New England utility needs to expand or replace a peak-shaving liquefier, Chart is essentially the only qualified domestic source.

Nippon Sanso Holdings Corporation (TSE: 4091; Tokyo; ~¥900B revenue FY2024; majority-owned by Mitsubishi Chemical Group) is the fourth-largest industrial gas company globally and the largest in Asia-Pacific. Operates in Japan as Taiyo Nippon Sanso (TNSC) and in North America via the Matheson brand. Designs and builds its own ASUs for its industrial gas business. Particularly strong in electronics-grade gases (ultra-high purity nitrogen, oxygen, argon for semiconductors) supplied to Japanese, Korean, and Taiwanese chip fabs. TNSC acquired Praxair's European industrial gas businesses in 2018 (as a merger remedy when Linde and Praxair combined) and Matheson Tri-Gas (North America) in 2004. One of the few companies globally with end-to-end ASU design, construction, and gas supply capabilities.