Source: People's Daily
Shenhua Baotou 1.8 million tons of coal-based methanol to 600,000 tons of olefins project. Photo courtesy of Dalian Institute of Chemical Physics, Chinese Academy of Sciences
Liu Zhongmin (first from left) communicates with team members. Photo courtesy of Dalian Institute of Chemical Physics, Chinese Academy of Sciences
Ethylene, propylene and other olefins are important organic chemical raw materials, which are widely used in industry, agriculture, medicine, environmental protection and other fields. Plastics, synthetic rubber, fibers, pharmaceutical raw materials, pesticides, coatings, etc., most of the important raw materials are olefins.
In the chemical industry, the mainstream method has been the production of olefin raw materials such as ethylene and propylene through petroleum processing.
"The basic national conditions of rich coal, poor oil and low gas determine that we cannot take the road of completely relying on petroleum to produce olefins." Liu Zhongmin, academician of the Chinese Academy of Engineering and director of the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences, said.
Since the 80s of last century, researchers from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences (hereinafter referred to as the Dalian Institute of Chemicals) began to explore and study coal-to-olefin technology. Since then, after nearly 40 years of continuous research by several generations of scientific researchers, United Engineering Company has finally successfully developed a complete set of industrial technology of methanol to olefin patented process technology (DMTO) with independent intellectual property rights, opened up a new route for the production of olefins from non-petroleum resources, and achieved a breakthrough in the industrialization of coal-to-olefins in the world.
Take on the challenge of world-class issues
In the 70s of the 20th century, due to the global oil crisis, oil prices rose sharply, and people were worried about the source of olefin raw materials.
Scientists came up with a way to first synthesize methanol from coal or natural gas, and then use methanol to make olefins. Some countries have successively launched scientific and technological research plans to replace coal with oil. Based on the national conditions of rich coal, poor oil and low gas, Chinese researchers have also taken action. In 1981, the production of olefins from methanol was listed as a key topic of the Chinese Academy of Sciences, and the Dalian Chemical Institute undertook this important task.
"At that time, coal synthesis of methanol already had a mature industrial technology, and methanol to olefins was a key core technology to be tackled, and it was also a very challenging topic worldwide." Liu Zhongmin said.
"Replacing oil with coal" is related to the long-term stable development of the mainland's economy and energy security, and it is difficult to achieve it. The Dalian Institute of Chemicals quickly established a research group headed by researcher Chen Guoquan and researcher Liang Juan. In 1983, at the age of 19, Liu Zhongmin entered the Dalian Chemical Institute to pursue a master's degree and immediately joined the team.
It all started in the lab.
"One of the first hurdles to overcome is to develop a catalyst that can convert methanol into olefins." Liu Zhongmin said.
At that time, there were two technical routes: ZSM-5 zeolite catalyst and SAPO-34 zeolite catalyst. The former has examples of industrial applications, and the risk is relatively small, while the industrial application potential of SAPO-34 zeolite catalyst needs further study. After weighing the considerations, the research team finally decided to "walk on two legs".
After several Chinese New Year's Eve of hard work, the team first synthesized ZSM-5 zeolite molecular sieve in China, taking the first step towards achieving the strategic goal of methanol to olefin. After that, the researchers took advantage of the victory and successively completed the 3 tons/year scale zeolite scale-up synthesis, 4-5 tons/year scale catalyst amplification equipment, and the methanol to olefin fixed bed reaction system and all peripheral equipment with a daily processing capacity of 1 ton of methanol, and completed the pilot test in 1993.
With the deepening of research, researchers found that SAPO-34 zeolite catalyst can greatly improve the yield of olefins, and the industrial application prospects are better. In 1995, the team used its own new process method of syngas to olefins through dimethyl ether to complete the 100-ton pilot test. The test results were very good, and the project was awarded the special prize of the Science and Technology Progress Award of the Chinese Academy of Sciences by the Chinese Academy of Sciences.
I originally thought that the project would proceed smoothly, but I did not expect the "mutation": the international oil price fell sharply, once falling to less than 10 US dollars / barrel.
"As a result, the cost of coal-to-olefins is too high compared to petroleum-to-olefins, so companies are not highly motivated to replace oil with coal to produce olefins." Liu Zhongmin said. For some time, the research stalled due to a lack of funding.
Industrial applications, to achieve a breakthrough of "zero"
The chemical industry is different from other fields, a new process can not be separated from the step-by-step scale-up, from the laboratory to the pilot to the industrial demonstration, and finally can be industrialized. This process requires a lot of money.
What to do?
Liu Zhongmin does not want to give up, he firmly believes that for the country, this research is of great and far-reaching significance. So, while promoting technology research and development, he began to look for investment everywhere, hoping to jointly develop with companies.
"It was a lot of pressure." Liu Zhongmin said frankly, "How to let enterprises understand our technological prospects and potential advantages, persuade them to support the construction of 10,000-ton industrial test equipment, and verify and improve technology in amplification is really a challenge for those of us who specialize in scientific research." ”
In 1998, Liu Zhongmin submitted a report to the Chinese Academy of Sciences, hoping to "borrow money" to continue to conquer this technology. Soon after, Liu Zhongmin's team received a special scientific research grant of 1 million yuan from the Chinese Academy of Sciences.
"With this funding, we further studied the reaction mechanism of the methanol-to-olefins process, refined the catalyst scale-up and process technology, and continued to look for opportunities for further scale-up trials." Liu Zhongmin said.
In 2004, the international oil price recovered, and methanol to olefins once again ushered in development opportunities.
Opportunities are always left to those who are prepared. After learning that Dalian Chemical Institute had developed a world-leading laboratory pilot technology for methanol to olefins and was looking for investment and partners, Shaanxi Province decided to cooperate with it to carry out industrial trials.
In August of that year, the industrial test plant with a total investment of 86.1 million yuan and an annual methanol processing capacity of 16,700 tons started construction in Huaxian County, Shaanxi Province (now Huazhou District, Weinan City). Liu's team set up camp at a local chemical plant and began a crucial industrial experiment.
"Initially, only the methanol-to-olefins industrial pilot plant stood alone on the entire site, and the plant infrastructure was rudimentary." Zhang Lingling, a team member and associate researcher of Dalian Chemical Institute, recalled.
It was under such difficult conditions that Liu Zhongmin led the team to spend more than 700 days and nights in the factory area. During this period, he rarely slept soundly, even after falling asleep at night, he would always get up after a while to see if the torch on the device was still on. If the torch burns, it means that the device is operating normally, and he dares to lie down and squint for a while, "If the fire is not bright, you have to run there quickly, indicating that there may be a problem." ”
As the head of technology, Liu Zhongmin is most worried about security. "More than 100 people, 36 meters high large installation, if there is a problem in one link, it may interrupt the rare opportunity for industrial testing."
After more than 700 days and nights of "fear", we finally ushered in an exciting moment. In May 2006, the industrial test of methanol to olefins was declared successful, and reliable data for the design and construction of large-scale plants were obtained.
Since then, the project has continued to progress smoothly. In 2010, Shenhua Baotou's 1.8 million tons/year methanol to olefin industrial plant was successfully put into operation, realizing the industrialization of coal-to-olefins for the first time in the world; In January 2011, it officially entered the commercial operation stage. As a result, Continental took the lead in achieving a breakthrough in the core technology of methanol to olefins and the "zero" industrial application.
Scientific research relay to promote technological upgrading
The long and arduous R&D process integrates the pursuit of scientific research and the dedication of three generations of Dalian Chemical Institute to national strategic needs. At the 2014 National Science and Technology Award Conference, methanol to olefin technology won the first prize of the National Technology Invention Award.
While receiving the honor, the team members felt a heavier burden on their shoulders. Continuous innovation and continuous upgrading of technology have become their new goals.
In 2015, the second-generation methanol-to-olefin (DMTO-II.) technology with higher olefin yield was successfully put into operation, further consolidating Continental's leading position in the world's coal-based olefin industrialization industry.
In November 2020, the third-generation methanol to olefin technology passed the identification of scientific and technological achievements. Compared with the previous two generations of technology, the third generation technology has increased the methanol processing capacity from 1.8 million tons to 3.6 million tons per year, which translates into olefin production from 600,000 tons to 1.35 million tons per year. The consumption per tonne of olefin methanol decreased from 3 tonnes to 2.6 to 2.7 tonnes.
"The methanol processing capacity of a single unit of the third-generation technology has been greatly increased, the cost per olefin has been reduced by about 10%, the energy consumption has been significantly reduced, and the economy has been significantly improved." Liu Zhongmin said.
Not long ago, based on the third-generation methanol to olefin technology, the world's largest single set of coal-to-olefin projects began construction in Ordos City, Inner Mongolia Autonomous Region.
Liu Zhongmin said: "After the completion and operation of the coal-to-olefin project, it will promote the transformation of coal resource products in Ordos and related regions from 'general processing' to 'high-end manufacturing', help realize the optimization of regional industrial structure, and promote the diversification of national olefin raw materials." ”
Up to now, Dalian Chemical Institute has signed 32 sets of equipment technology implementation license contracts, with an olefin production capacity of 21.6 million tons/year (accounting for about 1/3 of the current national production capacity); 17 sets of industrial plants have been put into operation, with a olefin production capacity of more than 10 million tons per year.
"Transform generation, develop generation, look ahead." This is the overall deployment of the research of Dalian Chemical Institute on the production of olefins from coal from methanol. Regarding the future, Liu Zhongmin said: "Just like a relay race, the mentor passed the baton of coal-to-olefins to me, and as the inheritor, I want to lead a group of young people to continue running." ”
People's Daily (Version 19, 09 October 2023)