A kind of fluidized bed reactor with internal circulation of various catalysts and its hydrogenation method

Abstract

The invention discloses a bubbling bed reactor for inner circulation of a variety of catalysts, and a hydrogenation method. The reactor comprises more than two sections of catalyst circulation zones arranged sequentially from top to bottom, wherein the interior of at least one section of the catalyst circulation zone is provided with a flow guiding member and more than one cyclone separators, thelower catalyst outlets of each section of the cyclone separator are communicated to the lower portions of each catalyst circulation zone, and are connected to each corresponding catalyst discharge port, the inlets on the upper portions of each section of the cyclone separator horizontally face the center or the inner side of the reactor, and each section of the flow guiding member is used for changing the flow direction of a fluid so as to make the fluid have a horizontal split velocity, such that part of the fluid flows to the inlets of each cyclone separator. With the reactor of the presentinvention, the complete fluidization and internal circulation of the multiple catalysts can be achieved, the flow rate of the liquid inside the bubbling bed can be adjusted, and the residence time ofthe catalyst internal circulation and the residence time of the liquid passing through the reactor can be adjusted.

Description

technical field [0001] The invention relates to a fluidized-bed reactor with internal circulation of various catalysts and a hydrogenation method thereof. Background technique [0002] The hydrogenation and upgrading process of heavy oil is a key step to increase the added value of oil products, and the reactor is the core device of the whole process. Due to the heavy oil's high viscosity, metal impurities, and high-carbon asphaltene content, conventional fixed-bed reactors are prone to problems such as catalyst bed blockage, greatly increased pressure drop, and catalyst deactivation during the hydrogenation process of heavy oil. These problems make it necessary for the fixed-bed reactor to frequently switch catalysts to maintain the activity of the bed layer; however, since the fixed-bed reactor must be shut down for catalyst loading and unloading, it is difficult for the fixed-bed heavy oil hydrogenation process to continuously process heavy oil economically and effectivel...

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Problems solved by technology

Therefore, this type of reactor can only adjust the residence time of the reactor through the inlet space velocity, not only has few operating means, but also has a slow response time

[0009] (2) Due to the influence of the fluid velocity of the fluidized bed and the size of the catalyst outlet of the three-phase device, it is difficult to form a circulation, and the adjustment range of the fluid velocity is very narrow

For example, when the fluid velocity of the ebullated bed is high and / or the catalyst feed opening of the three-phase device is large, the fluid in the ebullated bed flows upward directly through the catalyst feed opening, and no circulation can be formed; when the fluid velocity of the ebullated bed is small, it cannot be realized The light and heavy multi-stage catalysts are all in a suspended state; when the three-phase catalyst catalyst discharge port is small, it is easy to cause the discharge port to be blocked

[0010] (3) When the catalyst is unloaded online, a mixed reaction system containing a large amount of heavy oil and catalyst is directly drawn from the bottom of the reactor. When the catalyst is replaced quickly, a large amount of heavy oil is discharged instantly, which seriously affects the heavy oil in the reactor. The hydrogenation effect of oil, if the catalyst is replaced slowly, it will cause a very long time to replace the catalyst

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