New approaches have been developed for the efficient use of heavy oil

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Faced with the severe trend of increasing heaviness in global oil resources, how to make the most of low-quality heavy oil has become a problem that the refining industry strives to solve. At the recently held Summit Forum on Energy Security and New Energy Corridors in the West, China’s first industrial demonstration project for synthesizing crude oil using \"green hydrogen + low-quality heavy oil\" was officially launched. The Ashford Hydrodesorption Synthesis (ASHS) technology for the complete conversion of low-quality heavy oil via slurry-bed hydrogenation took a step forward from the laboratory stage toward large-scale industrial application. During the interview, the reporter learned that this technology breaks away from conventional pathways for heavy oil conversion, enabling efficient utilization of both conventional and unconventional petroleum resources to transform \"black solid waste\" into high-value \"green crude oil\". Heavy oil accounts for over 70% of the total resources, and the challenge of its efficient utilization has attracted considerable attention. \"The deep conversion and efficient use of heavy oil and residue have always been issues in the international refining industry.\" ”Tian Zhijian, head of the Fossil Energy and Applied Catalysis Research Department at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, and chief scientist at Zhongke Yaxin Photosynthetic (Xinjiang) Energy Co., Ltd., said. According to him, currently, global oil resources are showing a trend toward becoming heavier; of the approximately 10 trillion barrels of remaining oil reserves, over 70% are heavy oil reserves. In our country, the crude oil processing volume is approximately 708 million tons; the crude oil is generally heavy, with a residue yield of over 40%. After crude oil distillation to extract gasoline, diesel, and wax oil, a large amount of difficult-to-process residue often remains. In addition, there are also heavy oils such as ethylene tar, catalytic slurry, and coal tar, which are produced as by-products in the processes of oil refining and chemical processing. Currently, delayed coking is the mainstream heavy oil processing technology in China. Tian Zhijian pointed out that this process is energy-intensive and causes significant pollution; resource utilization is inefficient, resulting in large amounts of petroleum coke being produced each year, which prevents the maximum possible use of resources. “At present, China’s delayed coking capacity is around 140 million tons, and a large amount of petroleum coke is generated during the production of oil products. By 2025, China’s production of petroleum coke is expected to reach 31.73 million tons. At the same time, many refineries and chemical plants also generate large amounts of secondary tar; estimates suggest that nearly ten million tons are produced each year. These resources have not yet been utilized efficiently; converting them into oil products or chemicals can save a large amount of crude oil. ”Tian Zhijian said. In fact, this issue has long received significant attention from the relevant authorities. In February 2022, **four departments including the National Development and Reform Commission jointly issued the \"Guidelines for the Implementation of Energy Conservation and Carbon Reduction Transformations in Key Sectors of High-Energy-Consuming Industries\", which stipulated the need to \"promote the development and application of technologies for processing low-quality heavy oil feedstocks such as residue slurry-bed hydrogenation\". Tian Zhijian said, “Producing clean liquid fuels and chemicals from heavy oils such as oil sands asphalt, extra-heavy oil, and vacuum residue enables efficient utilization of conventional and unconventional petroleum resources, providing scientific and technical support for **energy security and energy assurance strategies.” ”Three technological breakthroughs have been made to fully utilize heavy oil and improve conversion efficiency; since 2010, Tian Zhijian’s research team has been working on this area and developed the ASHS technology. “The core objective of this technology is to hydrocrack the most difficult-to-convert asphaltenic components in heavy oil into light oil products; the yield of liquid products can reach over 97%, with little dry gas produced and no coking occurring. ”Tian Zhijian said. He pointed out that the technology has three major innovations. First, low-packaging nano-2D catalysts were developed. The catalyst particles have a length of less than 20 nanometers and a stacking layer count of less than 3; they possess properties such as surface amphiphilicity, high dispersion, and low packing density. They are compatible with the structure of asphaltenes, enabling the efficient hydrogenation conversion of asphaltenes. Tian Zhijian said that this catalyst has been produced on an industrial scale, with output ranging from tons to hundreds of tons, thus laying the foundation for the industrialization of this technology. Second, a new type of slurry bed reactor was developed, the gas-lifted circulating slurry bed reactor. “Gas enters from the bottom, creating a circulation that ensures very thorough gas-liquid contact. ”Tian Zhijian explained that the reactor enhances gas-liquid turbulent mixing through its structure and internal components, thereby achieving uniform temperature, low pressure drop within the reactor, and complete mixing of the materials. This design overcomes the engineering challenges of mass and heat transfer during the hydrotreatment of heavy oil, ensuring stable operation at high conversion rates. Third, innovate the process flow to achieve balanced hydrogenation conversion of heavy oil. Tian Zhijian pointed out that heavy oil is composed of four components: saturated fractions, aromatic fractions, resins, and asphaltenes, and it is difficult to achieve balanced hydrogenation of these components. In traditional processes, the hydrogenation of various components does not occur simultaneously, which can easily lead to coking. “Through process optimization, we ensured balanced hydrogenation of all components, achieving complete conversion with off-gas levels kept below 3%. ”He said. Test data show that for six typical heavy oil feedstocks, namely petrochemical residue, 90# asphalt, Fengcheng ultra-heavy oil, Tahe 60# asphalt, coal tar asphalt, and ethylene tar, the conversion rate using the ASHA technology exceeds 97%, with the yield of liquid products reaching over 99% ； For ethylene tar, which is the most difficult to convert, the ASHS technology can achieve nearly 100% conversion. The reporter learned that other similar slurry bed technologies achieve a maximum conversion rate of 90% for ethylene tar. In 2024, this technology passed the evaluation for scientific and technological achievements by the China Petroleum and Chemical Industry Federation. The evaluation committee believes that this technical indicator is advanced and highly practical; it constitutes a new process for the efficient conversion and lightening of heavy oil, different from conventional heavy oil hydrocracking, and represents an international leading level. It recommends accelerating research and development as well as the promotion of this technology. This technology has currently been included in the **Energy Administration’s Catalog of Advanced Technologies for Energy Saving and Carbon Reduction in the refining industry**. Helping to increase crude oil supply while reducing consumption: playing a key role in the entire industry chain. When talking about the technical prospects, Tian Zhijian is full of confidence: “ASHS technology will play a key role in the entire industry chain, from upstream extraction to downstream processing.” ”He classified the application scenarios of ASHS technology into two categories: “throttling” and “open source”. In terms of “throttling”, this technology can not only replace the delayed coking technology, which has a processing capacity of approximately 140 million tons per year, but also turn around 30 million tons of petroleum coke from waste into useful resources” ； It is better able to process low-quality heavy oils that are by-products of refining, converting tar into new aromatic materials. “At present, ethylene tar can only be used as boiler fuel or for the production of carbon black, whereas the ASHA technology enables nearly 100% conversion, yielding distillate oils with an aromatic content of over 98%, thus opening up a new production route for aromatics on a scale of tens of millions of tons. ”Tian Zhijian said. In terms of “open source”, this technology can be used for on-site upgrading of green hydrogen, and solvent-assisted SAGD can enhance the extraction of extra-heavy oil, thereby improving the quality of crude oil ； It can also be used to process medium-chain oleic blocks, opening up new pathways for oil supply. Based on this, Tian Zhijian proposed a new scenario for comprehensive energy applications: transporting solid asphalt back to China via the China-Europe freight train, using container storage in place of crude oil tanks to reduce investment; then combining this with hydrogen production using new energy sources, and employing advanced technologies to convert solid asphalt into lightweight, low-carbon synthetic crude oil, which is subsequently transported via pipelines in the west to refineries in the interior of the country. This vision has become a reality. On April 18, China’s first industrial demonstration project for the synthesis of crude oil using \"green hydrogen + low-quality heavy oil\" – the 1.6 million tons per year industrial demonstration project for the efficient transformation of imported solid asphalt using entirely green energy, carried out by Zhongke Yaxin Photosynthesis (Xinjiang) Energy Co., Ltd. – was officially launched. Leveraging ASHS technology, this project produces green hydrogen from wind and solar power in Xinjiang, and processes low-quality heavy oils such as solid asphalt imported from Central and North Asia, achieving an annual output of 1.6 million tons of low-carbon synthetic crude oil. The reporter learned that this technology has also been successfully applied in two major projects: the 5 million tons per year demonstration project for the efficient conversion of imported asphalt using 100% green energy in Songyuan City, and the 1.6 million tons per year demonstration project for the same purpose in Shanshan County. Yang Hansheng, chairman of Zhongke Yaxin Photosynthesis (Xinjiang) Energy Co., Ltd., said that by 2030, this technology is expected to enable green synthetic crude oil production on a scale of tens of millions of tons across the country.