METHOD FOR PRODUCING OLEFINIC HYDROCARBONS IN A FLUIDIZED BED OF A PULVERIZED CHROMIUM ALUMINA CATALYST Russian patent published in 2021 - IPC C07C5/333 C07C11/02 B01J29/90 

FIELD: olefinic hydrocarbons production.

SUBSTANCE: invention relates to a method for producing olefinic hydrocarbons by dehydrogenation of paraffinic hydrocarbons in a fluidized bed of a pulverized chromium alumina catalyst circulating in a system including a reactor with sectioning grids, a regenerator and a catalyst and transport gas distribution unit containing a vertical catalyst pipeline located in the reactor and regenerator for directing a mixture of catalyst and transport gas with an ascending flow with an expander with holes located at its upper end, connected to vertical drain risers, the ends of which are located in the upper part of the fluidized bed of catalyst, for directing the mixture of catalyst and transport gas in a downward flow. The method is characterized in that the catalyst line located in the reactor is used, the axis of which is shifted from the reactor axis by 30-90% towards the inner wall of the reactor, while the catalyst line located in the reactor is supplied to the expander, as well as vertical drain pipes to the openings in the reactor located in the reactor and in the regenerator, the expander is carried out with a radial bend, and the upper end of the catalyst line located in the reactor is placed perpendicular to the axis of the reactor, while a spherical expander with holes in its lower half of the sphere is used in the reactor and regenerator to connect with vertical drain risers, and the center of the expander is located coaxially with the catalyst line and the corresponding reactor and regenerator, while the supply of the catalyst line located in the reactor to the expander is carried out with a bend radius not exceeding 50% of the radius of the reactor; with a bend radius not exceeding the expander radius, the ratio of the expander diameter to the catalyst line diameter is in the range of 1.1-3.0.

EFFECT: use of the proposed method makes it possible to exclude deposits of monolithic coke on the catalyst pipeline, to reduce the erosion of the internal devices of the reactor and to ensure a consistently high yield of olefinic hydrocarbons.

2 cl, 1 dwg, 3 ex