LT3884B - Reactor of thermal cracking - Google Patents

Abstract

Thermal cracking reactor applies to equipment intended for a thermal cracking execution and may be used in the oil processing industry. The invention aims to simplify the structure of a thermal cracking reactor. The aim is achieved by the thermal cracking reactor operating on the basis of a rising hydrocarbon flow of thermal cracking products and consists of the upper branch pipe (6), upper bottom (5), casing (4), lower bottom (3) and a lower branch pipe (2), where there is installed a tangential gas-liquid flow deflector (1). The lower branch pipe (in metres) makes 0.014-0.12 of the centrifugal separation factor size part. Besides, the lower branch pipe has an intermediating flange connection.

Description

The invention relates to equipment for carrying out a thermal cracking process and can be used in the refining industry.

A thermal cracking process and reactor are known (see EP, 0193222, C10G 9/00). According to this patent, in the first stage of thermal cracking, partial hydrocarbon decomposition occurs, further decomposition products and non-decomposed hydrocarbons enter a phase separator, where the vapor phase is separated into components. The liquid phase enters the thermal cracking reactor. The design of the reactor is selected according to the tasks set.

The disadvantage of this technique is the complexity of the process technology using an additional apparatus operating at high temperatures.

It is a known thermal cracking reactor in which a gas-liquid flow, from bottom to top, acquires a rotary motion by means of helical guides. The latter can be installed throughout the reactor volume, either in the inlet or outlet sections of the reactor. In addition, the gas-liquid flow can be screwed in by installing a screw nozzle system or by tangentially introducing the gas-liquid flow into the reactor. Reactor temperature 410-470 ° C, pressure 2-20 atm, reactor residence time 5-100 min (see PCT Application No. 84/00035, C10G 9/16).

A disadvantage of the present invention is the complex design of the reactor and the relatively high process temperature.

The object of the invention is to simplify the construction of a reactor.

This is accomplished by the fact that the length of the bottom tube (in meters) of the thermal cracking reactor, which is based on the rising hydrocarbon thermal cracking product stream and consists of a top tube, top bottom, housing, bottom bottom and bottom tube with a tangential gas fluid flow guide. 0.014-0.12 centrifugal separation factor, in addition the lower flange has an intermediate flange connection.

The centrifugal separation factor is calculated from the ratio of the acceleration of the centrifugal force to the acceleration of the free fall (see K.F. Pavlov, P.G. Romankov,

A.A. Noskov Problems and Examples in the Course of Chemical Technology Apparatus and Processes, L,: Chimija, 1987, p. 576), viz. according to the formula:

f = (20 · D · n) ² / g; n = V / (3.14 D);

where: f is the centrifugal separation factor;

D is the diameter of the inlet flange, m;

n is the rotational speed, s; g - acceleration of free fall, m ² / s;

V is the hydrocarbon flow rate during injection into the reactor, m / s.

The invention is explained in the drawings (fig1, fig.2),

The thermal cracking reactor is comprised of a tangential gas fluid flow guide 1, a lower conduit 2, a lower bottom 3, a housing 4, an upper bottom 5, an upper nozzle 6.

The starting hydrocarbons are introduced tangentially through the tangential guide 1, tangentially into the lower port 2 of the reactor, which may be a composite (FIG. 2). Subsequently, the hydrocarbon stream enters the bottom bottom 3 of the reactor, then the casing 4, the top bottom 5, the top nozzle 6, from which the thermal cracking products are discharged from the apparatus.

Bottom nozzle 2 serves as a centrifugal separator. The dimensions of the nozzle are set to optimize the vapor phase separation to the center of the reactor and to provide the liquid phase with a torque that allows the liquid phase to rotate up to the maximum height of the apparatus walls. Under these conditions, a redistribution of the volumes occupied by the vapor and liquid phases in the reactor is achieved. The volume occupied by the liquid phase increases and the volume occupied by the vapor phase decreases. This increases the residence time of the liquid phase in the reactor and allows the target full hydrocarbon decomposition to be achieved at lower process temperatures.

Length of lower nozzle 2 of less than 0.014 f worsens the gas-liquid flow separation conditions, and increase of lower nozzle length more than 0.12 f increases the hydraulic resistance of the nozzle, and worsens gas-liquid flow separation.

The proposed technical solution allows to simplify the construction of the reactor and reduce the temperature of the thermal cracking process by 7-10 ° C.

Claims (2)

1. Thermal cracking reactor based on rising hydrocarbon thermal cracking product stream and consisting of tangential guide, lower nozzle, bottom bottom, housing, top bottom and top nozzle, characterized in that the bottom nozzle has a length of 0.014-0.12 centrifugal separation factor size. 2. A thermal cracking reactor according to claim 1, characterized in that the lower tube has an intermediate flange connection.