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Reduced-pressure deep drawing is an effective measure recognized by oil refining companies both domestically and internationally for saving energy, reducing consumption, and improving overall efficiency. How to achieve precise separation of light and heavy fractions while extracting as many light fractions as possible from crude oil remains a global challenge that the refining industry is eager to solve. Through more than 20 years of continuous research and development, institutions such as Xi’an Shiyou University, China University of Petroleum (Huadong), and the Yan’an Refinery of Shaanxi Yanchang Petroleum (Group) Co., Ltd. have developed the technology of \"precision separation of crude oil during distillation based on energy conservation and consumption reduction, along with its applications.\" They pioneered a technology for precise separation of crude oil at different pressure levels, along with the corresponding equipment; by integrating these processes and equipment, they help refining companies to save energy, reduce consumption, and improve efficiency. Not long ago, this achievement won the first prize in the Science and Technology Progress Award of the Shaanxi Province Science and Technology Award. Multiple technical challenges coexist. As a key component in the refining process, crude oil atmospheric and vacuum distillation technology is mature, but due to the large volume of material that needs to be processed and the need to operate at high temperatures, it remains a major energy consumer. Furthermore, the purpose of crude oil atmospheric and vacuum distillation is to extract as many light fractions as possible from the crude oil while achieving precise separation of different fraction types. However, since all the columns in this facility are fed with a vapor-liquid mixture, the actual flashing efficiency is less than 75%. Moreover, there is no efficient specialized equipment for stripping in the stripping section, both domestically and internationally, which results in poor separation of the oil at the bottom of the columns. Therefore, insufficient depth of vacuum distillation, poor quality of wax oil obtained from deep distillation, low yields of high-value light oils, and high energy consumption in atmospheric and vacuum distillation have become common challenges for refining companies. Zhang Juntao, a professor at the School of Chemistry and Chemical Engineering at Xi’an Shiyou University, told reporters that the research team he leads, together with Tian Yuanyu, director of the National Key Laboratory of Heavy Oil at China University of Petroleum (Huadong) and a distinguished professor at Xi’an Shiyou University, has been working for many years on precise separation techniques in crude oil distillation, energy-saving extraction methods, and the associated equipment. As early as 1996, they developed the world’s first original technology for tray plates specifically designed for NS-guided distillation. But the path of scientific research is not smooth. The traditional distillation mass transfer theory proposed by scholars at home and abroad based on gas-phase dispersion and liquid-phase dispersion mass transfer mechanisms focuses, in line with the principle of maximizing the interphase area, only on the gas-liquid interphase area at scales of several millimeters or more; it does not take into account the impact of interface renewal, and thus fails to provide theoretical guidance for the development of new types of efficient separation column internals. In addition, issues existing in current atmospheric and vacuum distillation units, such as unclear separation of bottom oil and increased distillation energy consumption while reducing the yield of high-quality distillates, are also obstacles that need to be overcome. At present, the deep extraction technologies that represent the international advanced level are only Shell’s technology based on heat extraction through overhead spray in the Netherlands, and KBC’s technology based on raising the outlet temperature of the vacuum distillation unit in the United States. However, both have the common drawback of increasing energy consumption while boosting the yield of wax oil, as well as leading to a decline in the quality of this wax oil. It is also difficult to control the key parameters involved in converting residue into asphalt, and the use of such technologies results in a \"smoking phenomenon\" due to an excessive amount of light components. Synergistic innovation achieves three goals at once. To address these technical challenges and the limitations of traditional mass transfer theories, the team started with fundamental research and proposed a new mass transfer model based on liquid-phase dispersion and coalescence. They developed a theory for mass transfer at the micro-nano scale at the gas-liquid interface, which is grounded in the regulation of momentum transfer in the three-dimensional space within the tower components, a mass transfer model for the renewal of the gas-liquid interface at the micro-nano scale, methods to enhance mass transfer through liquid-phase dispersion, and efficient three-dimensional coupling methods between tray and packing systems. This theory provides a basis for the development and selection of original separation equipment for towers. At the same time, the research team invented the NS distillation stripping unit, foam-removing and stream-regulating feeder, high-efficiency reduced-pressure cross-flow composite tray, as well as a series of associated internal tower components. These innovations enabled gas-liquid mass transfer to take place on a micro- and nano-scale, increasing the mass transfer area, time, and renewal rate by 2 to 3 orders of magnitude, thus providing a solid foundation for precise separation and energy-efficient distillation of crude oil. In terms of technological innovation, the team coordinated the crude oil distillation unit through the integrated use of process equipment, thereby improving the clarity of the oils obtained from each bottom of the distillation columns as well as the vacuum level in the flash section of the vacuum distillation tower. They developed a set of technologies for precise separation of crude oil that focus on energy savings and reduced consumption. For the first time, this approach enabled the deep distillation process, which typically results in lower-quality wax oils and higher energy consumption, to be adapted into an energy-efficient process that ensures high oil quality. Zhang Juntao explained that this integrated approach to collaborative innovation achieves three goals at once: improved distillation efficiency, more precise separation, and reduced energy consumption in atmospheric and vacuum distillation units. Compared with similar foreign technologies, the yields of diesel and wax oil increase by 3 percentage points and 4–6 percentage points respectively, while the system energy consumption is reduced by 20%. During the scientific research efforts, these devices and processes have collectively been granted 36 invention patents. In May 2021, the Shaanxi Chemical Industry Society organized an evaluation of this scientific and technological achievement; experts deemed that it exhibited significant innovation in terms of the complete set of technologies for atmospheric and vacuum distillation as well as the key equipment associated with it, reaching an internationally leading level. Energy savings and efficiency improvements in industrial applications. It is understood that this technology has been applied in 43 vacuum/atmospheric distillation systems owned by companies such as China National Petroleum Corporation, Sinopec, CNOOC, and Yanchang Petroleum; the associated tower internals have also been successfully used in 420 towers of various types at enterprises like Maoming Petrochemical, Shanghai Petrochemical, and Yanshan Petrochemical, yielding significant results in terms of energy savings, cost reduction, and improved efficiency. Compared with the F1 high-efficiency floating valve tray technology widely used in China today, the processing capacity of the NS cross-flow composite tray is more than doubled, the tray pressure drop is only 1/6, and the tray efficiency is increased by over 35%. According to statistics, over the past 3 years, since this technology was applied in the atmospheric and vacuum distillation units with a total capacity of 10 million tons per year at Yan’an Refinery of Yanchang Petroleum, Zhonghai Asphalt (Yingkou) Co., Ltd., and Shandong Huaxing Petrochemical Group Co., Ltd., it has resulted in an increase in sales revenue of 3.37 billion yuan and profits and taxes of 850 million yuan. Tian Yuanyu said that the research team will continue to improve the software for calculating tray effects in non-equilibrium stage models, as well as the software for simulating separation and coupling processes. They will also develop a set of evaluation and selection criteria along with guidelines for the use of precise separation techniques and energy-saving deep distillation methods in crude oil processing. Efforts will be made to promote the adoption of such technologies, thereby providing technical support for refineries to reduce energy consumption, improve efficiency, and achieve transformation and upgrading by shifting from producing ordinary oils to higher-value products.