CS256955B1 - Apparatus for converting carbon monoxide in non-adiabatic reactors with radial gas flow - Google Patents

Abstract

The solution relates to a device for converting carbon monoxide in non-adiabatic reactors with a radial flow of gas in a catalytic bed heated by the heat of reaction in a multi-pass heat exchange tube bundle arranged in the axial direction of the reactor and freely expanding in the catalytic bed, with a conical lower tube sheet and perforated tubes for supplying pressurized gas or liquid to facilitate emptying of the usable catalyst by mechanical release.

Description

(54) Equipment for converting carbon monoxide in non-adiabatic radial gas flow reactors

The invention relates to a device for converting carbon monoxide in non-adiabatic radial gas flow reactors in a catalytic bed heated by reaction heat in a multi-pass heat exchange tube bundle arranged in the reactor axial direction and in a loosely dilatating catalytic bed with conical bottom tube and perforated gas supply pipes or liquid to facilitate emptying of the usable catalyst by mechanical release.

The invention relates to a device for converting carbon monoxide in non-adiabatic radial gas flow reactors.

A conversion process is used to enrich the gases obtained by hydrogen fission or reforming of the hydrocarbons. Carbon monoxide combines with water vapor to form carbon dioxide.

CO + ^H 2 ° (g) - ^CO 2 ^{+ H} 2 ^{41 kJ} / ^mol

The equilibrium constant of this reaction log Kp - 1 797.8 / T - 1.648 5 decreases with temperature. The degree (achievable residual CO content) is limited by this dependence.

The residual CO content can only be reduced by cooling the reacting gases during the reaction.

The prior art CO conversion processes operate in two or more stages with intercooling. Exceptionally, non-adibatic axial flow reactors indirectly cooled in countercurrent or co-current are used.

Multistage conversion with intercooling has the following disadvantages:

- requires a larger number of apparatuses

- adiabatic course in each stage due to the temperature increase increases the equilibrium content of CO and thus decreases the reaction strength.

A single-stage non-adiabatic axial reactor has the following disadvantages:

- Poor utilization of reactor volume (there must be gas distributors above and below the catalytic converter),

- in the countercurrent arrangement, the lower part of the catalyst is supercooled; in co-current the top layer of the catalyst is subcooled,

- filling and emptying the catalyst is very difficult,

- the tube bundle reduces the cross-section of the reactor and thereby increases the pressure drop.

The above drawbacks are overcome by the device for converting carbon monoxide in a non-adiabatic single radial flow conversion reactor according to the invention, characterized in that the multi-walled tube bundle preferably formed from the u-tubes directly embedded in the catalytic bed is mechanically connected to the lower a conical tube sheet, which is also the bottom for the catalyst charge.

The tube plate is directly connected to the discharge opening for the catalyst, which is oriented in the center, and at the periphery the tube plate is mechanically connected to the external distributor. In the upper part of the reactor, the tube bundle is loosely supported. In order to facilitate the emptying of the catalyst, it is advantageous to provide a truncated conical lower tube sheet.

The advantages of the carbon monoxide conversion apparatus in the non-adiabatic radial gas flow reactors of the invention are lower reactor pressure loss and a high degree of conversion achieved. The use of these reactors saves installation of heat exchangers.

The attached drawing schematically shows a section through a conversion reactor where the catalyst is in a radial single pass bed. The reacting gas here first flows through a tube bundle where it is preheated and then enters the reaction. The tube bundle is three-pass, the conical tube sheet and catalyst emptying is the center.

An example of a reactor design has a flow resolved from the periphery through a catalytic bed towards the center. However, a similar solution is also possible with reverse flow. The number of tube bundle runs may also be different. However, a single-pass heat exchanger is disadvantageous both in terms of pipe dilatations and uneven temperature field. In the converter 10, a multistage tubular heat exchanger 2 is mounted in the charge (which consists of the catalyst) and is fixedly mounted in the lower tube plate 4 of conical shape. The distance tube tube 3 is used to lead the tube bundle out of the filling, through which the tubes pass freely and can freely thermally dilate. The spacer tube plate 2 forms a plurality of annulus to allow filling of the catalyst bed with the fillings 7 ^:

Single-threaded radial arrangement _1 cartridge with an outer annular distributor 6 and one central distributor 2 allows easy filling cartridges upper hatch J7 and simple emptying of the lower manhole 2 · Self-emptying chamber allows the catalyst conical bottom tube sheet 4. The central distributor 2 P ^ro removing products of reaction in its portion 9 which is in contact with the cartridge, perforated.

Non-adiabatic carbon monoxide conversion reactors can be used in ammonia and hydrogen plants, where they can advantageously replace two or more stage conversions with one apparatus.

Claims (1)

SUBJECT OF THE INVENTION Apparatus for converting carbon monoxide in non-adiabatic radial gas flow reactors with a multi-pass heat exchange tube bundle embedded directly in a catalytic bed, characterized in that the tube bundle (2) is mechanically coupled to a truncated cone-shaped lower tube plate (4) to which is supported by the catalyst filler (1) and which is directly connected to the discharge opening (8) and is also connected to the outer annular distributor (6), the tube bundle (2) being loosely mounted in the upper tube plate (3).