【Ten Years of Rapid Development in Chemical Processing Equipment】Successful large-scale development and application of counter-current continuous reforming technology from 2011 to 2022
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In the 2022 China Chemical Society Science and Technology Awards competition, the project \"Development of Energy-Efficient and High-Performance New Continuous Reforming Systems and Their Industrial Application\", led by Sinopec Engineering Construction Co., Ltd. (SEI), won the Special Prize for Scientific and Technological Progress. As early as 1998, SEI’s restructuring team began developing reverse flow continuous reforming plant technologies ； In 2011, this technology was selected as one of the “Ten Key” major scientific and technological projects by the group company, and a joint research team was established with the Shih Chien Institute and Jinan Refining & Chemical Corporation ； In 2013, the first 600,000 tons per year counter-current continuous reforming unit was successfully commissioned in Jinan, marking the successful development and application of counter-current continuous reforming technology ； In 2021, a 2.6 million tons per year counter-current continuous reforming unit was built and put into operation in Quanzhou, marking the successful large-scale development and application of counter-current continuous reforming technology. The successful development of this new energy-efficient continuous reforming technology package represents another achievement resulting from the group company’s collaborative efforts; it constitutes a technology package with complete independent intellectual property rights. This technology has significantly improved the level and competitiveness of continuous reforming technology in our country, promoted progress in related industries, driven the development of the equipment manufacturing sector, enhanced carbon reduction efforts, and brought about notable economic and social benefits, thereby achieving a high level of technological self-reliance and strength for this important fundamental process. On December 22, 2020, the 2.6 million tons per year continuous reforming unit of Sinochem Quanzhou’s 1 million tons per year ethylene and refining expansion project produced qualified products, achieving successful commissioning on the first attempt. The Quanzhou ethylene project is a key project under the 13th Five-Year Plan; its completion and operation are related to the overall strategic layout of the petrochemical industry as well as ensuring a secure energy supply. The 2.6 million tons per year continuous reforming unit is one of the core units of the Quanzhou ethylene project, and its construction commenced on March 8, 2019. On July 30, 2020, with CCCC’s support; on December 25, the catalyst recycling cycle was successfully established in the regeneration system, and the benzene, toluene, and C8+ products met the required quality standards and were sent for distribution. This facility is the largest continuous reforming unit in China to adopt domestic process packages, with a 100% localization rate for its technology and over a 95% localization rate for its equipment and materials. It has currently been nominated for the **Quality Project Gold Award**.
The results of this project were applied to Sinochem Quanzhou Petrochemical’s 2.6 million tons per year continuous reforming unit, resulting in a 1 percentage point increase in aromatic yield, a 0.5 percentage point increase in the yield of C₅+ liquids, and a 0.2 percentage point increase in pure hydrogen yield； Device energy consumption is reduced by 5%, while the energy consumption of the reforming-aromatics complex is decreased by 17% ； Catalyst wear is reduced by 57% to 82%. Enabling the application of key technologies: In addition to advanced technologies and processes, industrial application is also an important aspect of continuous reforming unit projects. To this end, the project team carried out research on the application of key technologies in continuous reforming units. The foundation design for Sinochem Quanzhou Petrochemical’s 2.6 million tons per year continuous reforming unit was undertaken by Sinopec Engineering Construction Co., Ltd. During the design phase, taking advantage of the capability for low-temperature heat exchange in reformed p-xylene aromatic compound plants, they organized technical investigations, evaluations, and analyses with major domestic turbine manufacturers. For the first time, they adopted a design scheme that utilized the 0.45 MPa steam generated within the domestic p-xylene plants as a source of low-temperature heat to power the turbines driving the reforming compressors. This approach not only ensured efficient utilization of low-temperature heat in large-scale reforming-aromatic compound plants but also reduced energy consumption by 64.9 kilograms of standard oil per ton of p-xylene, resulting in a reduction of carbon dioxide emissions by 228,000 tons per year – an impressive achievement in terms of energy savings and carbon reduction. As the first innovative pilot project in China to use 0.45MPa steam as the driving force for reforming units, the cleanliness of the steam pipelines is crucial to ensuring the stable operation of these units. The diameter of the steam pipeline at 0.45 MPa is 1 meter; there are no cases of similar installations featuring steam purging using pipes of this caliber that have been successfully applied in power turbines. The project team organized multiple reviews and revisions of the plan, calculated the parameters for steam purging, and optimized the purging process in terms of pipeline layout and other aspects, to ensure the safe and smooth commissioning of the facility.
After the installation was completed, the project team continued to optimize its operation by employing technical measures such as optimizing the temperature distribution across the reactors, adjusting the water-chlorine balance of the catalyst, and maintaining its optimal activity. At the same time, the project team focuses on reducing energy consumption and improving efficiency, striving for breakthroughs in increasing production and output, with an emphasis on promoting the application of relevant technologies. The fuel gas consumption in the continuous reforming heater represents the main energy consumption of the plant. By using efficient burners with a low excess air coefficient, low nitrogen oxide emissions, and low noise levels, as well as high-efficiency air preheaters, the flue gas temperature is reduced to below 90°C. This helps to minimize smoke loss, reduce emissions of carbon dioxide and nitrogen oxides, and achieves an average thermal efficiency of 94.5% for the heater. In addition, the project team optimized the operating conditions to reduce catalyst costs. They precisely calculate and optimize the catalyst under different operating conditions in order to increase gas flow; they also determine the optimal gas velocity for the catalyst to reduce its wear. They also introduced an independent low-flow heating pipe system to reduce the amount of steam used for heating, saving 70,000 tons of steam per year; they modified the clearance volume of the cylinders in the regeneration cycle air compressors, which reduced power consumption by 260 kilowatts and saved approximately 2.18 million kWh of electricity per year. Ultimately, Sinochem Quanzhou Petrochemical’s 2.6 million tons per year continuous reforming unit was successfully put into operation, marking a breakthrough in the development of large-scale domestic continuous reforming units from scratch.
What is reverse flow continuous reforming technology? The traditional naphtha continuous reforming process is a \"downstream\" continuous reforming process, meaning that the flow direction of both the reactants and the catalyst is the same. The reaction stream flows sequentially from the first reactor to the fourth reactor, and the regenerated catalyst also enters the first reactor first, before moving on to the second, third, and fourth reactors before returning to the regenerator. The flow direction of the catalyst is thus \"downstream\". In the counter-current continuous reforming process, the flow directions of the reactants and the catalyst are opposite to each other. The reaction stream still flows sequentially from the first reactor to the fourth reactor, but the regenerated catalyst first enters the fourth reactor, and then passes through the third, second, and first reactors in sequence before returning to the regenerator, moving in the opposite direction to the reaction stream; hence it is called a counter-current continuous reforming process.
What is reverse flow continuous reforming technology? https://bbs.hcbbs.com/thread-5498787-1-1.html (Source: Haichuan Chemical Industry Forum)
Before 2020, over 80% of the continuous reforming units in China used imported technologies, and those with a capacity of 2 million tons per year or more all relied on foreign technologies; there was an urgent need to develop high-level, independently developed complete sets of technologies for continuous reforming. Since 1998, SEI has collaborated with institutions such as the China Institute of Petroleum, Tsinghua University, and China University of Petroleum (Beijing) to carry out experimental research on counter-current reforming reactions, tests on the counter-current transportation of catalysts, studies on coking kinetics models, and development of new reactor structures; it has also developed control systems. In December 2009, SEI completed the development of a 600,000 tons/year counter-current continuous reforming process package ； In August 2010, it was approved by Sinopec ； In November 2011, an industrial-scale test was launched at Jinan Refining and Chemical Industry ； In September 2013, the 600,000 tons per year counter-current moving bed continuous reforming unit and its associated systems at Jinan Refining & Chemical were put into operation, marking the successful development and application of counter-current continuous reforming technology and achieving a breakthrough from \"zero to one\". In December 2020, the 2.6 million tons per year continuous reforming unit at Sinochem Group’s Quanzhou petrochemical plant was successfully put into operation, marking a successful large-scale application of counter-current reforming technology. This achievement represented a breakthrough in the development of domestic large-scale continuous reforming units, breaking the foreign technological monopoly on such units with capacities of over 2 million tons per year. Since June 2023, the 1.3 million tons per year continuous reforming unit at CNOOC Huizhou Petrochemical that utilizes counter-current moving bed continuous reforming technology, as well as the 2.6 million tons per year counter-current continuous reforming unit at Sinopec Hainan Refining & Chemical, have been successfully put into operation. “After 25 years of continuous efforts, we took the lead in developing a new countercurrent continuous reforming process of original design; this process boasts complete independent intellectual property rights and its overall level is at the international forefront, achieving high-level technological self-reliance and strength in an important fundamental process. ”This was introduced by Wu Defei, the lead developer of this technology, executive director of Sinopec Engineering Construction Co., Ltd. (SEI), ****.
As the leading organization, SEI carried out a series of engineering technology developments in collaboration with universities and research institutions during the experimental research phase of the counter-current continuous reforming technology, including unique catalyst circulation processes and catalyst regeneration processes； Safe, precise, and reliable control system ； Reforming reactor with better distribution performance and fewer \"dead zones\" ； Reforming reactor that can save more than 20% of steel usage ； Technologies such as low-temperature heat recovery have led to the development of a complete set of counter-current continuous reforming process technologies with distinct technical features and advantages. At the same time, SEI also collaborated with Tsinghua University to develop computational software for fluid distribution in reforming radial reactors, filling the gap in domestic research on the fluid dynamics of continuous reforming reactors. For the counterflow continuous reforming technology to move beyond the laboratory, industrial-scale testing is essential. In 2009, Jinan Refining & Chemical planned to use the counter-current continuous reforming process technology to expand and upgrade its 300,000 tons per year semi-regenerative reforming unit, with SEI being responsible for designing the 600,000 tons per year process package. On September 27, 2013, the world’s first continuous reforming unit with a capacity of 600,000 tons per year using a counter-current moving bed technology was put into operation, making China the third country in the world capable of using this continuous reforming technology on a commercial basis in the international market.