Original Article from http://duchuang.sznews.com/ 2023/04/14 15:57 Duchuang/Shenzhen Business Daily, Trainee Reporter Zhang Guofeng

       In early April, a petrochemical company of CNOOC was carrying out a planned shutdown overhaul every four years. Compared with the past, this year's overhaul was more expected. In order to solve the problems of corrosion of refinery internals, they adopted CTS technology, a new technology invented by an enterprise in Nanshan District, before three overhaul cycles, but could this technology stand the tests of time? What was the effect? Refinery engineers were waiting for the results of the tower opening inspections.

CTS Technology Overcomes the Corrosion Problem of Refinery Internals

     On that day, the overhaul work was carried out intensively. "Dang, Dang, Dang", in a pile of 317 L steel internals that were corroded into slag after the tower was opened, the CTS internals with complete shape appeared, and the crisp sound of metal plucking could be heard when plucking, which proved that the stainless steel internals treated by CTS technology had withstood the test of three cycles and attracted the admiration of the on-site staff.

     The scene of that day deeply impressed Wang Jinguang, the technical director of Sinopec Engineering Incorporation (SEI), the refinery design entity, who has been engaged in the design and research of refinery material engineering and corrosion control.  Every time the refinery was shut down for overhaul, he would fly from Beijing to the site to investigate the operation and corrosion of the whole plant. On the same day, Wang Jinguang came to the site again to observe the fifth section packing of the vacuum tower with the most serious corrosion environment. In a stack of 317 L trim packings that were heavily corroded, he found that the CTS-treated internal packings placed three overhaul cycles ago were still intact, with no significant corrosion or damage. He exclaimed: "This is amazing!"! It has once again set a new record for the life cycle of internals. After years of theoretical research and practical testing, I am more confident to confirm that CTS technology has proved to be able to withstand the test of harsh corrosive environments such as high acid. Wang Jinguang introduced that as the key equipment of the refinery, the internal packing was filled in the whole distillation tower, which directly contacted crude oil at high temperature and reduced pressure, and played an effective role in separating crude oil components. The acid value of crude oil used in CNOOC refinery has been at a high level for a long time, which is one of the refineries with the most severe naphthenic acid corrosion in the world, and the selection of internal packing is a headache industry problem. Even if the 317 L steel material with higher price and higher grade is used, it will last less than 4 years. The risk of corrosion of refining equipment is that the equipment is blocked the refining efficiency is reduced due to corrosion, and the safety accident is caused by equipment perforation due to corrosion. The use of CTS material not only greatly prolongs the service life of refining equipment, and improves the safety of equipment, but also saves the overhaul costs of refineries, and also brings benefits to the improvement of refining efficiency.  For the corrosion problem, CNOOC has been constantly exploring. Through discussion with Shenzhen Candor Technology Co., Ltd., they decided to seek the best technology through innovation. 

     Opportunities are always seized by those who are prepared. In 2022, themed at "Industrial Synergy and Win-win & Cooperation", in the matching activities between large-scale backbone enterprises and small and medium-sized enterprises in Nanshan District, CNOOC, a central enterprise, and Shenzhen Candor, an SRDI small and medium-sized enterprise once again succeeded in joining hands on the basis of previous cooperation, pushing the cooperation between the two sides to a deeper level, and the activities of "hand in hand" once again yielded fruitful results. Candor is a national high-tech enterprise, an SRDI small and medium-sized enterprise in Shenzhen, and also an industrial model enterprise under the designated size of Nanshan District. The company has dozens of invention patents. CTS is a high-performance stainless steel anti-corrosion and anti-coking technology invented by Candor, which is used in the fields of petroleum, chemical industry, marine and other harsh corrosive environments. The technology has been recognized by academician-level experts organized by the China Petroleum and Chemical Industry Federation as "the international leading level in surface modification, corrosion resistance and coke resistance of stainless steel for the petrochemical industry". Fei Weiyang, professor of chemical engineering at Tsinghua University and academician of the Chinese Academy of Sciences, also commented: "The advanced anti-corrosion technology of Candor can ensure the performance of the vacuum tower and allow it to work steadily for a long time. Candor has accumulated stressful cases and satisfied results."