Why did Qingdao Jinneng’s world’s largest propylene separation tower undergo major renovation after two years of operation?
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This equipment is claimed to be the largest in the world. It adopts Lummus' Catofin process and is the world's first and currently the largest single-scale PDH device. Equipment assembly began in 2019 and was put into production in 2020. A major transformation of the internal structure was carried out in May 2022. On June 7, the propylene tower of the world's largest 900,000 tons/year propane dehydrogenation (PDH) unit of Jinneng Chemical (Qingdao) Co., Ltd. has been operating stably for 18 days continuously after undergoing energy-saving and efficiency-enhancing transformation, marking the successful start-up of the transformation project at one time. Compared with before the transformation, the efficiency of the propylene tower has been greatly improved, the reflux ratio has been reduced by 20%, and the separation accuracy has been significantly improved. The propylene product content exceeds 99.6%, and the propylene content at the bottom of the tower has been reduced from 1.5% to 2% before the transformation to less than 0.5%, greatly increasing the propylene yield.
The propylene tower is the core equipment of the PDH unit. According to reports, Jinneng Chemical’s propylene tower has an upper tower diameter of 11.3 meters and a lower tower diameter of 11.9 meters. They both adopt a six-overflow tray design. The tray design is difficult and requires high separation efficiency. The energy-saving and efficiency-enhancing renovation of the propylene tower of Jinneng Chemical's PDH unit adopted the ADV-TDD patented technology of Beijing Zehua Chemical Engineering Co., Ltd. This technology is a third-generation high-efficiency tray technology developed on the basis of the classic ADV high-efficiency tray and combined with Beijing Zehua’s newly developed suspended downcomer technology with precise liquid distribution function. Compared with the ADV tray, the ADV-TDD tray can further increase the processing capacity, and the efficiency of the tray can also be significantly improved. Especially in the application of four-overflow and six-overflow trays, the efficiency advantage is more prominent. Introduction by the technical person in charge of Beijing Zehua: “To achieve optimal separation efficiency with multiple overflow trays, the liquid-gas ratio in each bubbling zone must be the same. Therefore, we need to accurately distribute the gas and liquid in each bubbling zone. The larger the tower diameter and the greater the number of tray overflows, the greater the necessity for such precise distribution. The tray can achieve precise distribution of liquid in each bubbling zone through the optimized design of the downcomer structure, so that the liquid and gas in each bubbling zone are completely matched to ensure the same liquid-gas ratio in each bubbling zone, thereby maximizing the efficiency of the multi-overflow tray. ”@RedLee_ZZHI @书通@wise人明@the majestic Ultraman. @Xuehaiyouzi
ADV-TDD patented technology of Beijing Zehua Chemical Engineering Co., Ltd. This technology is a third-generation high-efficiency tray technology developed on the basis of the classic ADV high-efficiency tray and combined with Beijing Zehua’s newly developed suspended downcomer technology with precise liquid distribution function. Compared with the ADV tray, the ADV-TDD tray can further increase the processing capacity, and the efficiency of the tray can also be significantly improved. Especially in the application of four-overflow and six-overflow trays, the efficiency advantage is more prominent.