Catalytic cracking method and equipment for hydrocarbon oil

Abstract

The invention discloses a catalytic cracking method for hydrocarbon oil. The method is characterized by comprising the following steps of: (1) undergoing a first contact reaction on a hydrocarbon oil raw material and a first cracking catalyst in a first reactor, and performing first oil-agent separation on a mixture of oil gas and the catalyst after the first contact reaction; (2) undergoing a second contact reaction on oil gas obtained after first oil-agent separation and a second newly-added cracking catalyst in a second reactor, and performing second oil-agent separation; and (3) feeding a part of or all of a spent catalyst obtained in the step (2) into the first reactor. The invention further provides catalytic cracking equipment for hydrocarbon oil. Due to the adoption of the method and the equipment, the problem of poor activity in the second reactor caused by great reduction in the activity of the catalyst discharged from the first reactor is solved, and the yields of dry gas and coke can be lowered greatly.

Description

technical field [0001] The invention relates to a hydrocarbon oil catalytic cracking method and hydrocarbon oil catalytic cracking equipment. Background technique [0002] Catalytic cracking is one of the most important secondary processing methods in the field of petroleum refining. [0003] Judging from the development in recent years, catalytic cracking technology will continue to develop around the following main aspects: [0004] Process heavy raw materials. Due to the growing demand for light oil and the increase in crude oil prices, the use of catalytic cracking technology to process heavy and low-quality feedstock oils such as atmospheric residues, vacuum residues, coker wax oils and deasphalted oils can yield greater economic benefits. How to solve the problems of serious heavy metal contamination of the catalyst and high coke yield when processing heavy raw materials is an important direction in the development of catalytic cracking technology. [0005] A new p...

AI Technical Summary

Problems solved by technology

However, due to the gas-solid co-current flowing against the gravity field, there is a large axial and radial flow inhomogeneity in the riser, large gas-solid backmixing, uneven residence time distribution, etc., and the coke generated during the reaction is deposited on the catalyst. On the surface and active center, the activity of the catalyst drops sharply

Studies have shown that the current catalyst activity at the outlet of the riser is only about 1 / 3 of the initial activity, and the reaction takes about 1 second, and the catalyst activity drops by about 50%.

In this way, in the second half of the riser reactor, the activity of the catalyst drops sharply, the catalytic effect is greatly weakened, the thermal cracking reaction increases, more dry gas is produced and the olefin content of gasoline is increased.

Images