| As an important strategic disposable energy consumption, oil has always been regarded as the blood of industry. However, with the continued exploitation of oil, the problem of heavy oil become more and more. Large parts of the imported oil are low-quality production with high-sulfur and high carbon residue due to the political economy in the world. Therefore, it is imperative to accelerate research on heavy residue processing technology.Abroad, typically residue hydrotreating processes are H-Oil process and LC-Fining process. At home, STRONG fluidized bed residue hydrotreating technology, co-developed by Sinopec Fushun Research Institute of Petroleum and Petrochemicals and Luoyang Petrochemical Engineering Corporation/Sinopec, has a very good development prospects, because of its use of rosphere particles catalyst, without high temperature and pressure circulation pump, using the built-in three-phase separator and so comes the realization of an efficient, safety and environmental protection goals, and have complete independent intellectual property rights。At present, the research on the STRONG fluidized bed mainly concentrated on the catalyst development, operation conditions control, etc., and the research on the internal flow of the reactor seldom reports. Because there is a very complicated three-phase current flow in the STRONG fluidized bed residue hydrotreating reactor, it is difficult to test its internal flow conditions directly. Computational Fluid Dynamics (CFD) provides a new means to observe the development of flow conditions inside the reactor. The cold model of the STRONG fluidized bed was simulated by the commercial software Fluent. The main works are as follows:1、The multiphase flow flowing E/E/E three-phase flow model was established, ignoring its added mass force and lift, consider gas-liquid, liquid-solid and gas-solid drag force. The liquid-solid force model uses Syamlal-O’Brien model, and the gas-liquid and gas-solid force model uses Schiller-Naumann model. A physical model STRONG fluidized bed was established, and its discrete treatment was carried out at the same time. The NS equation was solved by SIMPLE algorithm.2、Simulations show that the distribution of gas-liquid-solid three phase in the STRONG reactor are uniform, and the gas holdup are more than the water vapor holdup and solid holdup, which shows that under the standard operating conditions a relatively high vapor pressure and vapor fraction exist in STRONG fluidized bed reactor, which is very conducive to the catalytic hydrogenation reactions.3、Viewed the influence on flow conditions in the reactor, when the velocity gas-liquid two phase increased in proportion. The experimental results show that due to the increase of the gas phase is greater than the increase of liquid phase, and makes the air inside the reactor containing rate increased, the liquid holdup decreased, the solid catalyst increased at first and then decreased with. The feed rate of the reactor increased, increase the degree of turbulence within the reactor, flow dead zone area is reduced.4、Examines the influence on flow conditions in the reactor, when the liquid feed rate increased. Simulation results show that the gas holdups in the reactor are reduced, catalyst containing rate increase, when the speed of the liquid phase increases. This suggests that the the high liquid velocity rate is not conducive to the reaction.5、With residue of liquid feed, we investigated the effects of residual oil viscosity on flow conditions inside the reactor. The simulation results show that the distribution on the viscosity of the air-liquid-solid holdup in the reactor is not very clear, but when the viscosity increases, the resistance increases, the reactor will swirl locally. |
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