【Major Chemical Equipment Innovations】197–Just released! Five hydrogenation reactors for the Yangzi Petrochemical project have been completed

A great nation with great achievements – NB! Youyu, could you provide more details on the equipment parameters?

On April 11, 2018, the project titled “Nationalization Project for Ultra-large Diameter and Ultra-thick Wall Hydrogenation Reactors”, which was led by Sinopec Group and involved six organizations including Sinopec Luoyang Engineering Company, Sinopec Engineering Construction Co., Ltd., Yangzi Petrochemical Company, Jinling Petrochemical Company, First Heavy Machinery Co., Ltd., and Second Heavy Machinery Group Corporation, passed the evaluation by an expert panel at Yangzi Petrochemical in Nanjing. The advanced construction technology for hydrogenation reactors with ultra-large diameter and ultra-thick walls (referred to as \"double ultra\") developed in this project has been successfully applied in the residue hydrogenation units of Yangzi Petrochemical and Jinling Petrochemical. Compared with using imported equipment, it saves nearly 100 million yuan in investment costs and reduces the manufacturing cycle by 6 months, bringing significant economic and social benefits.

Experts such as Shou Binan, vice president of the China Special Equipment Inspection and Research Institute and president of the China Pressure Vessel Association, believe that the integrated construction technology for \"double-high\" hydrogen reactors is a domestic innovation with independent intellectual property rights; the overall construction technology has reached international advanced levels; the project holds 4 authorized patents, including 3 invention patents, and it is recommended that its application be further promoted. In 2007, the maximum inner diameter of domestically manufactured \"Shuangchao\" hydrogenation reactors reached 5200 millimeters, with a wall thickness of 347 millimeters. For a long time, the lack of comprehensive construction technology for \"double-ultra\" hydrogenation reactors in China has restricted the scaling up of domestic residue hydrogenation units. In 2008, Yangzi Petrochemical and Jinling Petrochemical needed to build residue hydrogenation units with capacities of 2 million tons per year and 1.8 million tons per year respectively, and had to either import equipment from abroad or develop it independently. For independent research and development, it is necessary to address the design of \"double-high\" hydrogenation reactors. To this end, Sinopec took the lead in establishing a project team, with 6 organizations participating in order to work together on this task. During the development process, various relevant organizations actively participated and made concerted efforts, making significant contributions to the completion of the project. In particular, Sinopec Luoyang Engineering Company faced numerous challenges in its research and development efforts; after conducting various domestic and international studies, it put forward updated requirements for the entire process of reactor design, manufacturing, and operation, making significant contributions to the design work. Through collaborative efforts, they overcame challenges related to the uniformity, density, and isotropy of forgings with extremely large diameters and thick walls, and mastered the comprehensive construction technology for double-ultra hydrogenation reactors.

Since the dual-supercritical reactors developed were put into use in the residue hydrogenation units of Jinling Petrochemical and Yangzi Petrochemical, evaluations conducted on-site as well as inspections and tests during shutdowns have shown that all performance parameters meet the design requirements, thus achieving the intended objectives. Jinling Petrochemical’s 1.8 million tons per year residue hydrogenation unit was put into operation in October 2012. It was shut down for major maintenance in October 2015, and after comprehensive inspections, no significant defects such as corrosion or hydrogen blistering were found. Yangzi Petrochemical’s 2 million tons per year residue hydrogenation unit was put into operation on July 19, 2014, and the reactors developed for it were subjected to practical operation tests. After comprehensive inspections, they were found to be in good condition, with no defects exceeding acceptable limits, indicating that the four dual-supercritical hydrogenation reactors developed by the research team and manufactured by Sinopec fully met the design requirements. Sinopec Yangzi Petrochemical’s newly built 2 million tons per year residue hydrogenation unit was designed by Sinopec Luoyang Engineering Company, installed by Sinopec Fourth Construction Company, and the four reactors were manufactured by China National Second Heavy Machinery Group Corporation. During operation, as the quality of the feedstock deteriorates, Yangzi Petrochemical conducts real-time monitoring of catalyst performance and life prediction, thereby optimizing and adjusting the feedstock processing strategies in a timely manner. This ensures that the removal efficiencies of various components by the residue catalyst remain at high levels, satisfying the requirements of the downstream catalytic cracking units. To date, the residue hydrogenation unit at Yangzi Petrochemical has operated for two cycles. Based on these first two cycles, the four double-ultra hydrogenation reactors have met the process operation requirements, the demands posed by low-quality crude oil, as well as the production load; no abnormal deformation or leakage was observed during operation, indicating that they are suitable for long-term operation in petrochemical facilities. Compared with the previous imported manufacturing approach, the equipment investment alone saves 53.34 million yuan; the manufacturing cycle is shortened by 6 months compared to imported equipment, allowing the facility to start operating earlier and generate benefits sooner. Thus, development was successfully completed relying on a total of 8 hydrogenation reactors of ultra-large diameter (inner diameter of 5400 millimeters) and ultra-thick walls (wall thickness of 340 millimeters), one from Jinling Petrochemical with a capacity of 1.8 million tons per year and another from Yangzi Petrochemical with a capacity of 2 million tons per year. The delivery time was reduced by 3 to 6 months compared to importing equipment from abroad, allowing Jinling Petrochemical and Yangzi Petrochemical to save a total of 93.34 million yuan in investment costs. It has greatly expanded the technical parameters of hydrogenation reactors in China, raising the actual manufacturing capacity of such reactors to a world-class level of 5400–6000 millimeters in length and 425 millimeters in wall thickness; it has also reduced manufacturing costs, thereby creating conditions for saving investment in new projects. Thanks to the research and development efforts of our team, the successful fabrication of the dual-supercritical reactors for the residue hydrogenation unit at Zhejiang Petrochemical recently has raised China’s manufacturing capabilities for large-scale hydrogenation reactors to an internationally leading level. The development of the complete set of technologies for double-supercritical hydrogenation reactors has also directly contributed to the technological advancement and enhanced competitiveness of domestic manufacturing enterprises closely related to this project in areas such as steelmaking, forging, heat treatment, and non-destructive testing, thereby improving the economic performance of China’s heavy equipment manufacturing enterprises. It has further boosted the capabilities of domestic manufacturers in producing hydrogenation equipment with thick forged and welded structures, enabling better satisfaction of the needs of the petrochemical industry for large-scale equipment.

Since the operation of the residue hydrogenation unit began at the end of July 2014, Yangzi Petrochemical has maintained the feedstock composition for this unit, thereby achieving cost reduction and improved efficiency. By the end of November, the proportion of residue in the feedstock used by Yangzi’s residue hydrogenation unit had reached over 65%, which is at the advanced level of Sinopec; this setup enables the production of approximately 1,000 tons per day of high-value products such as gasoline, diesel, and propylene, resulting in the lowest costs and the highest benefits. Residue is the residue left over after petroleum is processed through distillation; residue hydrogenation involves converting this low-cost residue into products with high added value, such as refined oil and naphtha. Despite their strong profitability, residue hydrogenation units are very delicate, especially regarding the strict requirements for the heavy metal content in the feedstock. The residue hydrogenation unit at Yangzi Petrochemical has an annual production capacity of 2 million tons; it is the company’s first residue hydrogenation unit. To maximize efficiency, Yangzi Petrochemical focuses first on the source by purchasing specific crude oils for the residue hydrogenation unit, storing them in dedicated tanks, and transporting them separately to avoid contamination. Due to the numerous transfer steps in the external port, it is easy for such crude oil to become contaminated by other crude oils with higher levels of heavy metals; therefore, Yangzi Petrochemical conducts strict quality inspections on every shipment of crude oil that arrives at the port. Furthermore, Yangzi Petrochemical will also conduct analyses for heavy metal content in the crude oil that arrives at the plant; at the same time, it plans to transport the purchased crude oil by water specifically to the plant, in order to completely avoid contamination of the crude oil caused by pipeline transportation. The crude oil most suitable for processing in the residue hydrogenation unit is Oman crude. Due to the high price of Oman crude, Yangzi Petrochemical mixes Oman crude with Basra crude in a certain proportion to create a feedstock tailored for this unit, thereby reducing raw material costs. To ensure the stability of the feedstock for the residue hydrogenation unit during the production process, Yangzi Petrochemical implements measures for separate storage and processing of the feedstock for this unit. The residue hydrogenation unit is designed with four residue storage tanks, A, B, C, and D, which can hold 48,000 tons of vacuum distillation residue. On September 21 this year, Yangzi Refinery successfully put into operation an optimized residue processing process, enabling the separate storage of different types of residues in dedicated residue tanks and increasing the available storage capacity. In order to process more residue and reduce costs, Yangzi Refinery optimized its operations, increasing the amount of residue fed into the residue hydrogenation unit from 120 tons per hour to 160 tons per hour; this resulted in a residue utilization rate of 65%. The processing capacity of the unit for residue was thus maximized, effectively improving the economic efficiency of its operation.