RU2443752C1 - Reactor for liquid-phase thermal cracking - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention refers to reactor including the housing with lower and upper cover plates and raw material supply branch pipes and thermal cracking products discharge branch pipes, inner pipe rigidly located coaxially to the housing and installed in the housing with possibility of its removal from reactor, in the lower part of which a distributor made in the form of flattened cone is located, and in upper part of which a detachable pipeline connected to a remote pipe is located; lower end of remote pipe is tangentially connected to lower part of the housing; at that, distributor is installed on plates inside raw material supply branch pipe; lower end of inner pipe is equipped with a support ring arranged in the neck of lower part of the reactor, and discharge branch pipe of thermal cracking products is arranged in the neck of upper part of reactor; at that, diameter of remote pipe is less than diameter of inner pipe.

EFFECT: reducing the coking of reactor walls and increasing efficiency of thermal cracking process.

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Description

The invention relates to oil refining, in particular to reaction apparatuses used in the processes of thermal cracking and visbreaking of crude oil.

A reactor for liquid-phase thermal cracking is known, comprising a housing with an inner pipe fixed in it, in the lower part of which there is a mother liquor made in the form of a truncated cone, the upper base entering the inner pipe, in the lower base of which there is a pipe for supplying water vapor coaxially with the inner pipe (Pat. RF No. 2277115, C10G 9/14, op. May 27, 2006, BI No. 15).

A disadvantage of the known reactor is the risk of coking of the annulus between the inner tube and the reactor vessel due to the relatively low turbulence of the feed stream in it, which contributes to the formation of stagnant zones.

The closest to the claimed object in technical essence and the achieved result is a reactor for liquid-phase thermal cracking, containing a housing with upper and lower covers and pipes for supplying raw materials and removal of thermal cracking products, and in the lower cover there is a mother liquor made in the form of a truncated cone entering the upper the base in the inner pipe, which is stationary coaxially to the body and installed in the body with the possibility of its extraction from the reactor, an external reaction zone, the upper hour which is communicated with the inner pipe, and the lower part - with the lower part of the reactor vessel with the possibility of tangential entry of the reaction mass into the annular space between the inner pipe and the vessel, while the upper part of the external reaction zone is communicated with the inner pipe through a removable pipe (US Pat. RF № 2372378, C10G 9/14, Op. 10.11.2009, BI No. 31).

A disadvantage of the known reactor is that in order to increase the efficiency of the thermal cracking process due to the uniform distribution of the reaction mass velocities in the reactor volume (inside the pipe and in the annulus), it is necessary to increase the diameter of the inner pipe, and hence the dimensions of the mother liquor (distributor), which leads to cumbersome reactor design.

The present invention is aimed at improving the efficiency of the thermal cracking process by uniformly distributing the reaction mass velocities in the reactor volume without increasing the bulkiness of the latter while reducing the complexity of the repair work.

This is achieved by the fact that in a reactor for liquid-phase thermal cracking containing a housing with lower and upper covers and nozzles for supplying raw materials and removal of thermal cracking products, an inner pipe located motionless coaxially with the housing and installed in the housing with the possibility of its removal from the reactor, in the lower part which is the distributor, made in the form of a truncated cone, and in the upper - a removable pipe in communication with the remote pipe, the lower end of which is tangentially connected to the lower part of the housing, According to the invention, the distributor is mounted on the plates inside the raw material supply pipe, the lower end of the inner pipe having a support ring located in the neck of the lower part of the reactor, and the pipe for removing the thermal cracking products is placed in the neck of the upper part of the reactor, while the diameter of the remote pipe is made smaller than the diameter inner pipe.

Placing the distributor on the plates in the raw material supply pipe and supplying the lower end of the inner pipe with a support ring located in the neck of the lower part of the reactor will ensure uniform distribution of the reaction mixture in the reactor volume by equalizing the areas of the inner pipe and the annulus without increasing the bulkiness of the latter and, as a result will increase the efficiency of the thermal cracking process.

Also, the placement of the pipe for removal of thermal cracking products in the neck of the upper part of the reactor will allow, due to the concentration of the output stream of thermal cracking products in it, to reduce the coking capacity of the upper part of the reactor. And the implementation of the remote pipe with a smaller diameter than the inner pipe will allow, due to the compression of the vapor-liquid flow, to increase its hydrodynamic characteristics and, as a result, by effectively centrifugally moving the reaction mass flow in the annulus to reduce the coking ability of the reactor walls during the operation of the cracking unit.

In addition, the installation of a support ring at the lower end of the inner tube located in the neck of the lower part of the reactor, and on the upper retainers with a gap between the neck of the upper part of the reactor and the inner pipe, will make it possible to clean its walls with high-pressure water jets without removing the latter consequence, reduce the complexity of the repair work.

The attached figure shows the proposed design of the reactor in section.

The reactor for liquid-phase thermal cracking of petroleum feedstock contains a housing 1 with a lower 2 and upper 3 caps and an internal pipe 4 built into it. A pipe for supplying raw materials 5 is fixed on the lower cover 2, in which a distributor 7 is made on the plates 6, made in the form of a truncated cone. The lower end of the inner pipe 4 is equipped with a support ring 8 located on the neck of the lower part of the reactor, and the upper end is equipped with clamps 9 and is installed in the neck of the upper part of the housing 1. On the upper cover 3 is fixed a removable pipe 10 connected to the remote pipe 11, the lower end of which by means of a tangential input pipe 12 is connected to the lower part of the housing 1. In the neck of the upper part of the housing 1 there is a pipe for removal of thermal cracking products 13 connected to the pipe 14. Between the removable pipe 10 and the outlet hydrochloric pipe 11 disposed compensator 15.

The reactor operates as follows. The raw material after heating in a tubular furnace (not shown in the figure) through the raw material supply pipe 5, the distributor 7, made in the form of a truncated cone, is fed into the inner pipe 4. The vapor-liquid stream of the reaction mixture through the inner pipe 4 is fed upstream into the removable pipe 10, and then the downward flow through the bypass pipe 11 enters through the pipe of the tangential input 12 to the bottom of the housing 1. The reaction mass entering the bypass pipe 11 of a smaller diameter than the diameter of the inner pipe 4 is compressed and tangential through the pipe th input 12 enters the annular space of the inner tube 4 and the body 1, and is formed into a rotating upward spiral feed stream. Under the action of centrifugal force, the organized upward spiral-shaped feed stream of the reaction mass is concentrated in the neck of the upper part of the reactor and through the pipe outlet of the products of thermal cracking 13 is discharged from the reactor into the pipeline 14.

In the case of coking of the inner pipe 4 by thermal cracking products, the removable pipe 10, the upper cover 3 and the lower cover 2 are removed, and it is cleaned with a high-pressure water jet from top to bottom. When coking the annulus, the inner pipe 4 is raised to a height that provides clearance between the support ring 8 and the neck of the lower part of the reactor, the inner pipe 4 is fixed on the neck of the upper part of the reactor and the walls of the housing 1 are cleaned.

Thus, placing the distributor on the plates in the raw material supply pipe and supplying the lower end of the inner pipe with a support ring located in the neck of the lower part of the reactor will ensure uniform redistribution of the reaction mixture in the reactor volume without increasing the bulkiness of the latter design, and the placement of the pipe for the removal of thermal cracking products the neck of the upper part of the reactor and the implementation of the remote pipe with a smaller diameter than the inner pipe will reduce the coking of the walls of the reactor ora and, as a consequence, increase the efficiency of the thermal cracking process.

Claims (1)

A reactor for liquid-phase thermal cracking, comprising a housing with lower and upper covers and nozzles for supplying raw materials and removal of thermal cracking products, an inner pipe located motionless coaxially with the housing and installed in the housing with the possibility of extraction from the reactor, in the lower part of which there is a distributor made in in the form of a truncated cone, and in the upper one, a removable conduit in communication with a remote pipe, the lower end of which is tangentially connected to the lower part of the housing, characterized in that elitel mounted on the plates inside the raw material supply pipe, the lower end of the inner tube is provided with a support ring arranged in the throat of the bottom of the reactor and the nozzle outlet of the thermal cracking products is placed in the neck of the upper part of the reactor, the diameter of the external pipe is made smaller than the inner diameter of the pipe.

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