Future Prospects of Steel for Petroleum and Petrochemical Industries

2.1 New Material Requirements for Petrochemical Equipment Development

The petrochemical industry is currently undergoing a transformation period. On one hand, the future of the petrochemical industry will develop toward large-scale, integrated, digitalized, and environmentally friendly directions. On the other hand, the national “3060” carbon reduction requirements are driving China’s energy industry policy to transform toward green energy industries. Therefore, the development of new generation “green energy materials” should be considered for inclusion in the steel industry’s agenda. The characteristics of green energy materials are mainly reflected in the material’s high purity, good corrosion resistance, excellent weldability, and long-term service safety.

From the current development trend, green energy mainly includes hydrogen energy and related industries, CCUS, comprehensive utilization of LNG and liquid ammonia, etc. Traditional petrochemical industries are also gradually transitioning to clean energy industries. Large-scale green hydrogen is replacing coal-to-hydrogen and natural gas-to-hydrogen in refineries. Natural gas-to-hydrogen is purified to supply hydrogen stations. Green process technologies such as electric heating replacing gas and oil heating furnaces in refineries are gradually replacing traditional process technologies. These green process technologies have significantly different material requirements compared to traditional refinery processes.

2.2 Overall Considerations for Future Material Demand in Petrochemical Equipment

Currently, the material quality level, varieties, and specifications covered by domestic pressure vessel steel standards can meet the material requirements for petrochemical equipment. However, considering the processing of inferior crude oil, application of new processes and technologies, and the transformation to green refineries and rapid development of new energy industries in China’s petrochemical industry in the next 5-10 years, it is necessary to further improve the quality level of current pressure vessel steel products, upgrade materials that have problems in use, and quickly develop new materials that can be engineered under extreme service conditions of ultra-high temperature, ultra-low temperature, and ultra-high pressure, expand new varieties of high-grade materials (such as nickel-based alloys), and develop new generation petrochemical equipment materials in terms of strength enhancement, wall thickness reduction, and performance preservation.

2.2.1 Product Quality Enhancement

1) High strength, good welding performance, good matching of strength and toughness;

2) High purity materials (lower content of impurity elements such as As, Sn, Sb);

3) High cleanliness materials (lower P, S, H, O, N content);

4) Uniform composition and properties at the head and tail of steel plates;

5) Good surface quality of steel plates.

2.2.2 New Material Development

1) Low alloy steel with normalizing (allowing rapid cooling) + tempering for operating temperatures of 350-550°C, suitable for future petroleum, petrochemical, and coal chemical processing of inferior crude oil and coal chemical equipment materials;

2) Nickel-based alloy materials for operating temperatures of 500-800°C, suitable for future petrochemical equipment materials under ultra-high temperature conditions;

3) High alloy steel materials for operating temperatures of 100°C to -269°C under medium-low pressure or high pressure operating conditions, suitable for future equipment materials under low temperature and ultra-low temperature environments;

4) High-strength austenitic stainless steel with strength performance improved by 2-3 times compared to current austenitic stainless steel, suitable for current refinery high-pressure equipment and pipeline materials, reducing wall thickness and field welding workload;

5) Functional materials for electric heating or energy conversion, suitable for future refinery transformation from fuel-type to green electric and environmentally friendly type.

2.2.3 Material Upgrading

1) Researching solutions from material perspective for temper brittleness, hydrogen brittleness, and hydrogen corrosion problems of chromium molybdenum steel used in hydrogenation high-pressure equipment;

2) Solving intergranular corrosion damage and chloride ion stress damage problems of austenitic stainless steel from material perspective;

3) Low-cost corrosion-resistant (high sulfur, high acid) super austenitic, duplex steel, ferritic stainless steel applications in petrochemical industry;

4) Complete varieties of carbon steel and low alloy steel materials applications (such as quenched and tempered steel, TMCP process materials);

5) High-strength Ni-Mn-N series low-temperature steel that can replace nickel-based low-temperature materials.

2.3 Development Prospects for Petroleum and Chemical Industry Equipment Materials

2.3.1 New Generation Cr-Mo Steel for Hydrogenation and Coal Chemical Fields

Currently, large-scale oil refining hydrogenation unit hydrogenation reactors have a maximum equipment diameter of 5800mm and maximum equipment wall thickness of 350mm, manufactured using 2.25Cr-1Mo-0.25V materials. The heaviest domestic hydrogenation reactor has reached about 3000 tons, and equipment weight brings a series of technical challenges for material smelting, forging, processing, equipment manufacturing, transportation, and installation.

Requirements for High-end Chromium Molybdenum Steel:
• Strength level: 720-850MPa
• No temper brittleness and hydrogen brittleness damage
• Equipment wall thickness and weight reduced by 20%-30%
• Low temperature -30°C impact absorption energy greater than 200J

2.3.2 New Generation TMCP Process High-Strength Low Alloy Steel

Large-scale equipment brings large tower diameters exceeding 8000mm, pipeline diameters exceeding 4000mm, equipment wall thickness above 100mm, and single tower weights of 300-1000 tons, resulting in exponentially increased material and manufacturing costs and increased difficulty in on-site pipeline fabrication.

Specific Requirements:
• General-purpose yield strength level 390-420MPa normalized steel for vessels
• Medium-high strength greater than 490MPa TMCP vessel steel
• 690MPa quenched and tempered steel for vessels

2.3.3 New Generation Composite Materials with Special Rolling Process

Currently, domestic rolling composite technology is increasingly mature. The base layer thickness of rolled composite steel plates is 6-200mm, and the composite layer thickness is 1-20mm. The composite process is vacuum composite and continuous rolling, with room temperature bonding strength exceeding 300MPa and 100% bonding rate between base and composite layers.

Application Prospects:
• Base material thickness up to 200mm rolled composite plates
• Various corrosion-resistant composite layer materials (stainless steel, nickel alloys, titanium, copper)
• Special process rolled composite pipe manufacturing
• Seamless composite pipes for large-diameter natural gas transmission pipelines

2.4 Future Development Prospects for Hydrogen Energy Materials

Driven by domestic “dual carbon” policies, the development of the hydrogen energy industry has entered the fast lane. In the field of hydrogen “storage and transportation,” liquid hydrogen storage, metal hydrogen storage, organic liquid hydrogen storage, high-pressure gas hydrogen storage, pipeline hydrogen transportation and other hydrogen storage technologies are continuously increasing basic and applied research efforts, striving to reach the level of large-scale industrial application as soon as possible.

Key Development Areas for New Materials:

1) Hydrogen-resistant, micro-alloyed, weldable new materials with tensile strength up to 1000MPa for hydrogen storage equipment;

2) High purity, low hydrogen brittleness Cr-Mo steel materials with tensile strength 950-1200MPa for seamless hydrogen storage cylinders;

3) 300 series and high-strength austenitic stainless steel with good impact and welding properties at -269°C, plate thickness 10-80mm, without martensitic transformation for large-scale liquid hydrogen storage;

4) Metal and non-metal composite materials for high-pressure hydrogen storage containers to reduce weight and manufacturing costs;

5) Large thickness, high-strength nickel-based alloys or precipitation hardening stainless steel at -269°C for liquid hydrogen compressors, expander cylinders, pump housings, etc.;

6) Low-cost, high-strength hydrogen transmission pipeline steel and pipeline fittings;

7) Alloy steel materials with constant expansion or low expansion coefficient at ultra-low temperatures for liquid hydrogen isolation components.

Conclusion

The future development of steel for petroleum and petrochemical industries requires continuous innovation in material technology to meet the evolving demands of green energy transformation, equipment upgrading, and extreme operating conditions. The steel industry must strengthen fundamental research and develop new materials adapted to various petrochemical equipment application scenarios to support China’s energy security and industrial competitiveness in the global market.