Established the first cyclone separator laboratory with three young teachers. During the experiment, they carefully observed and scientifically analyzed, and identified the main contradiction in the guide vane cyclone tube - particle entrainment caused by short-circuit flow. They cleverly used the sharp steering of the cyclone to solve this problem. In 1986, the research group’s first national invention patent was born (86100974.6-split core tube used in cyclone separators). The EPVC-IA guide vane type high-efficiency cyclone tube produced by this patent was used in Daqing Petrochemical Company After being adopted in the third-stage cyclone separator (referred to as "three-cyclone") of the main plant, it turns out that there are still particles larger than 20 μm in the high-temperature (650°C) flue gas entering the flue gas turbine (referred to as "smoke machine") at the outlet of the three-cyclone separator. Particles are now completely removed, and the content of 10-12μm particles is below 3, and the dust concentration is accordingly reduced to below 200mg/m3. The service life of the hood has been extended from only three months to more than three years, reaching an international standard. The advanced level of similar products won the second prize of the Sinopec Corporation's Science and Technology Progress Award in 1987 and the third prize of the National Science and Technology Progress Award in 1988. Later, most refineries across the country adopted this result and achieved significant economic benefits. Therefore, in 1991, he won the second prize of the Science and Technology Progress Award of the State Education Commission. In order to meet the needs of different refineries, the scientific research team developed the EPVC-IB type high-efficiency cyclone tube for Yanshan Petrochemical Company Dongfanghong Refinery, the EPVC-II type for Shijiazhuang Refinery, and the Shengli Refinery and Maoming Petrochemical Company Refinery. It was developed into EPVC-III type, and a series of EPVC products have been formed since then.
As the catalytic cracking feed oil becomes heavier and worse, the requirements for the performance of the catalytic tricycle are becoming more and more stringent. To this end, under the guidance of Shi Mingxian, the scientific research team developed newer PDC and PSC high-efficiency cyclones, which brought the performance of the three-cyclone to a new level. In 1994, it was first used at Luoyang Petrochemical Plant. Excellent performance has been revealed after use. There are basically no fine particles larger than 7~8μm in the high-temperature flue gas entering the hood from the three-turn outlet, and the dust concentration has dropped below 100mg/m3, reaching the international level at that time and ensuring The catalytic cracking unit, the heart of the plant, has been operating safely for a long time. After 1995, it was rapidly promoted and applied in large areas, and more than 1,000 sets have been promoted so far. This technology won the third prize of the Science and Technology Progress Award of Sinopec Corporation in 1996 and the second prize of the Science and Technology Progress Award of the Ministry of Education in 1999.
Although cyclone separation technology is a universal traditional technology with a history of hundreds of years and seems to have a simple structure, due to the complexity and variability of the three-dimensional flow and separation of gas-solid two-phase inside it, it has not yet been formed. A set of universal and mature design theories and methods, especially at high temperatures and high concentrations, is more difficult. Countries only have proprietary confidential technologies established based on experience.
The catalytic cracking unit, the main unit of my country's oil refining industry, has undergone creative development since its advent in 1964. However, the high-temperature cyclone separator, one of the key equipment related to the material and energy consumption of the unit, has always been It bothers people that if they don’t have their own design technology, they will simply use it, causing the device’s agent consumption to remain high for a long time.
The common practice abroad is to improve the structure of the cyclone separator to improve its performance. However, it is a big problem to improve its performance under the premise that high temperature and high concentration require a simpler structure. After many years of theoretical research and experimental summary analysis of multiphase swirl flows, Shi Mingxian believes that the way to solve the problem may lie in "optimized combination of sizes." On the basis of carefully studying the changing rules of the flow field and concentration field in the cyclone separator, he first clearly put forward the new point of view that "there are three weak links in the cyclone separator: top ash ring, short-circuit flow and ash hopper backmixing". The influence of cyclone separator size and operating conditions on these weak links was summarized in theory and practice, and a new "cyclone separator size classification optimization combination design method" was created, and calculation software was compiled for engineering design. use. At the appraisal meeting, it was unanimously recognized as "the first of its kind at home and abroad." Since then, for the first time, my country has its own "catalytic cracking high-temperature cyclone separator design technology."
The PV type high-efficiency cyclone separator designed with it has been adopted by almost all refineries across the country in just 8 years, completely solving this problem in the catalytic cracking unit and promoting the formation of my country's unique catalytic cracking family technology. Complete sets are domestically produced. This technology won the first prize of the Science and Technology Progress Award of Sinopec Corporation in 1990 and the second prize of the National Science and Technology Progress Award in 1991. So far, more than 1,000 PV-type high-efficiency cyclone separators have been promoted and used, saving the country about 150 million yuan every year.
Acrylonitrile production technology has long been monopolized by the patents of large foreign companies, and the prices charged are extremely high. For this reason, our country has spent a lot of foreign exchange. In order to break this monopoly, Sinopec Corporation has made arduous efforts and has made major breakthroughs in its core issues - catalyst and reactor technology. However, the three-stage cyclone separator in the reactor has not been solved. In 1996, Sinopec handed over this task to Shi Mingxian. Relying on his profound knowledge of cyclone separation technology, he guided young teachers. In less than a year, he confirmed that their PV-type cyclone separator was slightly better than similar foreign products in terms of theoretical calculations and large-scale comparative experiments. . Then it took another year to develop the world's unique "acrylonitrile series-one two-stage cyclone separation technology."
At that time, the United States announced the development of a new two-stage series connection technology only two years earlier than them. However, one large series and two small ones, each group was still three, and the reactor space occupied was not Too much reduction. Shi Mingxian's scientific research team developed a series of one, with only two in each group, which can reduce the space occupied by 30%. This means that when a reactor needs to increase its production capacity by 30%, it will not be restricted by the cyclone separator, creating very favorable conditions for the expansion and efficiency of the acrylonitrile unit. This achievement has been verified in applications in petrochemical plants such as Daqing, Shanghai Gaoqiao and Qilu, and the consumption of very expensive catalysts has been significantly reduced.
The catalytic cracking unit is the main force of oil refining production, and the riser-settler system is its heart. It contains many technical issues, one of which is of great concern is how to achieve rapid and efficient gas-solid separation at the riser outlet, rapid oil and gas extraction, and efficient catalyst stripping. The scientific research team led by Shi Mingxian identified the needs of production. Starting in 1995, it developed three sets of new technologies with its own patents for three consecutive years: baffle stripping rough spin (FSC for short), swirling fast spin... (VQS for short) and Circulation Stripping Quick Separator (CSC for short). The first two technologies have been successfully applied in production equipment, with the output-to-input ratio close to 10, resulting in significant economic benefits. They have also played a very important role in my country's original "Quan Daqing Reduced Residue Catalytic Cracking" new process. In the fierce competition with large foreign companies, we have won a valuable place.
Clean and efficient combustion of coal - power generation, is a high-tech that is being developed internationally and is also one of my country's key scientific and technological projects in the 21st century. Among them, pressurized fluidized bed combustion combined cycle power generation (PFBC for short) and integrated coal gasification combined cycle power generation (IGCC for short) are the two main directions. They both urgently need reliable and efficient high-temperature gas-solid separation equipment. This is a very difficult task, and so far no country has fully achieved it. In the mid-1980s, Shi Mingxian led a research team to participate in PFBC technology research led by Southeast University. They planned to proceed in two phases based on national conditions. The first stage requires the removal of 7 to 8 μm fine particles, and the dust concentration is below 150 mg/Nm3. In 1993, the DTC-type small multi-tube high-efficiency cyclone separator was successfully developed, and the small-scale thermal model test has confirmed that it can achieve this indicator. Then a 15Mwe pilot power station was built in Jiawang Coal Mine in Xuzhou. The second stage is to overcome high-temperature ceramic filters. The scientific research team focuses on developing a new powerful and efficient pulse backflush cleaning system.