Petroleum hydrocarbon multistage fluidization catalytic reaction method and reactor

Abstract

The invention belongs to the technical field of petroleum hydrocarbon catalytic conversion, in particular to a petroleum hydrocarbon multistage fluidization catalytic reaction method. The reaction method realizes zonal multistage reaction in a reactor, including a first-stage reaction of raw oil, a second-stage reaction, a first-stage and a second-stage cracking reaction process of light hydrocarbon. The catalyst replenishment and catalyst activity control are realized in the secondary reaction process of the catalytic cracking feedstock oil. The invention makes catalytic feedstock oil and light hydrocarbon be subjected to catalytic cracking conversion under respective reaction zones and reaction conditions, the multi-stage step selection control of catalyst and reaction temperature is realized, the multi-stage reaction and the step arrangement of catalyst and temperature can be realized in one reactor, so that the olefin yield and selectivity can be improved, and the yield of coke and other by-products can be reduced significantly. At that same time, the invention provides a petroleum hydrocarbon multistage fluidization catalytic reactor.

Description

technical field [0001] The invention belongs to the technical field of catalytic conversion of petroleum hydrocarbons, and in particular relates to a petroleum hydrocarbon multistage fluidized catalytic reaction method and a reactor capable of producing more propylene. Background technique [0002] The catalytic cracking unit is the main gasoline production unit and also an important production unit of propylene. Propylene is one of the most important petrochemical raw materials. Drawing on the operation and design experience of the conventional heavy oil catalytic cracking reaction-regeneration system, researchers at home and abroad have developed a series of technologies for the production of propylene by catalytic cracking of heavy oil. [0003] China University of Petroleum (East China) developed TMP technology on the basis of two-stage riser catalytic cracking technology. This technology uses heavy oil as raw material, utilizes the process characteristics of two-stage...

AI Technical Summary

Problems solved by technology

Regardless of DCC or DCC-PLUS, a reactor is divided into two cracking reaction zones in series, that is, the riser and the fluidized bed bed are both subjected to catalytic cracking reaction, the riser part is used for raw oil cracking reaction, and the fluidized bed bed Part of the intermediate product in the riser reaction zone is further subjected to a secondary cracking reaction to increase the production of propylene; since the catalyst in the fluidized bed reaction zone is the raw material for the raw oil reaction, the small molecule catalytic cracking reaction in the fluidized bed reaction zone The performance is reduced, and it is necessary to further increase the reaction temperature to increase the thermal cracking to increase the yield of propylene, which further reduces the selectivity of propylene; both DCC and DCC-PLUS use regenerant circulation, and the reaction zone of the fluidized bed bed with a fixed amount of raw material The space velocity can only be controlled by the change of the catalyst material level in the fluidized bed bed, and the catalyst outflow port must be set in the fluidized bed bed area to realize the material level control through the catalyst outflow; due to the requirements of catalyst entrainment and gas-solid separation, the fluidized bed There is a dilute phase space between the bed reaction zone and the gas-solid separator, and the oil and gas still carry a large amount of catalyst when they leave the fluidized bed, and the residence time of the oil and gas from the fluidized bed to the gas-solid separator is more than 20 seconds When adopting fluidized bed bed reaction, the carrying of the catalyst above the catalyst material level and the residence time of oil and gas will inevitably cause further side reactions, further thermal cracking of propylene, affecting product distribution and propylene selectivity, and it is difficult to terminate the reaction in time; in addition, DCC and The catalyst in the DCC-PLUS fluidized bed cracking reaction zone is a carbon-deposited catalyst after the reaction of feedstock oil. In order to increase the propylene yield, it is necessary to further increase the reaction temperature in the fluidized bed reaction zone, which will inevitably lead to restrictions on catalytic cracking reactions and increased thermal reactions. Significantly lower selectivity to propylene, leading to higher dry gas and coke yields

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