The computational fluid dynamics(CFD) code, FLUENT, was used to simulate the liquid-phase FCC diesel hydrotreating tubular reactor with a ceramic membrane tube dispenser. The chemical reaction and reaction heat were a...The computational fluid dynamics(CFD) code, FLUENT, was used to simulate the liquid-phase FCC diesel hydrotreating tubular reactor with a ceramic membrane tube dispenser. The chemical reaction and reaction heat were added to the model by user-defined function(UDF), showing the distribution of temperature and content of sulfides, nitrides, bicyclic aromatics and monocyclic aromatics in different parts of the reaction bed. When the pressure was 6.5 MPa, the amount of mixing hydrogen was 0.84%(m), the space velocity was 2 h-1 and the inlet temperature was 633 K, the temperature reached a maximum at a height of 0.15 m, and the range of radial temperature reached its maximum(2.5 K) at a height of 0.15 m. It indicated that the proper ratio of height to diameter of catalyst bed in the tubular reactor was 5-6. The increase of inlet temperature, the mixing hydrogen and the decrease of space velocity led to the decrease in the content of bicyclic aromatics, sulfides and nitrides, and the increase in monocyclic aromatics content, while the high temperature increased. The results were in good agreement with experimental data, indicating to the high accuracy of the model.展开更多
Urban smog issue has become more and more heated topic in China in recent years.Vehicle pollution is one of the main reasons for smog and haze in most large and medium-sized cities in the country.Maybe it is not surpr...Urban smog issue has become more and more heated topic in China in recent years.Vehicle pollution is one of the main reasons for smog and haze in most large and medium-sized cities in the country.Maybe it is not surprising now that the nation drives 95 million cars,second only to the United States with 240 million.Therefore,China has released a series of policies to alleviate the increasingly severe urban smog issues and accelerate upgrading of oil products quality.展开更多
文摘The computational fluid dynamics(CFD) code, FLUENT, was used to simulate the liquid-phase FCC diesel hydrotreating tubular reactor with a ceramic membrane tube dispenser. The chemical reaction and reaction heat were added to the model by user-defined function(UDF), showing the distribution of temperature and content of sulfides, nitrides, bicyclic aromatics and monocyclic aromatics in different parts of the reaction bed. When the pressure was 6.5 MPa, the amount of mixing hydrogen was 0.84%(m), the space velocity was 2 h-1 and the inlet temperature was 633 K, the temperature reached a maximum at a height of 0.15 m, and the range of radial temperature reached its maximum(2.5 K) at a height of 0.15 m. It indicated that the proper ratio of height to diameter of catalyst bed in the tubular reactor was 5-6. The increase of inlet temperature, the mixing hydrogen and the decrease of space velocity led to the decrease in the content of bicyclic aromatics, sulfides and nitrides, and the increase in monocyclic aromatics content, while the high temperature increased. The results were in good agreement with experimental data, indicating to the high accuracy of the model.
文摘Urban smog issue has become more and more heated topic in China in recent years.Vehicle pollution is one of the main reasons for smog and haze in most large and medium-sized cities in the country.Maybe it is not surprising now that the nation drives 95 million cars,second only to the United States with 240 million.Therefore,China has released a series of policies to alleviate the increasingly severe urban smog issues and accelerate upgrading of oil products quality.