German Democratic Republic	PATENT Economic Patent Granted pursuant to § 5 para. 1 of the amending law to the Patent Act	96 152
Office for Inventions and Patents	Additional patent to the patent: -- Filing date: September 17, 1971 (WP B 01 j / 157 789) Priority: -- Issuing date: March 12, 1973	Int. Cl.: B 01 j, 1/00 Cl.: 12 g, 1/01

Published in the version submitted by the applicant

Inventors: Klemt, Harry;

Pitzing, Rudi;

Götze, Wilhelm;

Hien, Grad. Eng., Helfried;

Bernhardt, Grad. Chem. Dr. Dieter;

simultaneously Gänsicke, Grad. Eng. Werner;

Krüger, Grad. Chem. Arnulf

Holder:

Device for Uniform Distribution of a Liquid

among the Tubes of a Tube Reactor

96 152	9 pages
(52) Ag 141 73/DDR. - 7079

The invention relates to a device for the uniform distribution of a liquid among the tubes of a tube reactor. The tubes are filled with a catalyst, over which the liquid trickles down.

It is known to arrange an essentially horizontal distributor base, which is provided with apertures, in the upper section of the reactor, for the purpose of a uniform distribution of mixtures of liquid and vapor on a contact bed comprising catalyst particles, where this mixture flows through the reactor from the top to the bottom. Inserted into the apertures in the distributor base are tube segments, which extend upwards and are provided with cover plates, arranged at a distance from the ends of said tube segments. Mounted in the upper boundary layer of the fixed bed are upwardly open, permeable baskets, the result of which is a prolonged duration of action of the catalyst between the regenerations and a decrease in the catalyst’s tendency to increase the pressure drop during the reaction. The baskets, which are made of a woven wire fabric, define the liquid-permeable

cavities in the surface of the contact bed and also hold back dirt particles, which are entrained in the feed medium. The upper end of the tube segments, which are attached in the distributor base, is provided with rectangular slots or serrated edges for the liquid overflow. The tube segments project somewhat downwards beyond the bottom boundary surface of the distributor base, so that liquid can drip off better onto the surface of the reactor bed. However, these tube segments may also serve the purpose of introducing the gas phase into or over the bed; and in the bottom section of said catalyst bed these tube segments are connected to the wire basket, projecting into the catalyst bed. The liquid/vapor mixture is sprayed over the entire cross section of the distributor base by means of a perforated, downwards convex baffle plate.

These distribution systems are suited for the distribution of liquid/vapor mixtures or also the distribution of liquids over a fixed catalyst bed. They are not suitable for the distribution of liquids among the individual tubes of a tube reactor. Especially in the case of catalytic reaction processes in the trickle phase, it must be guaranteed that all of the tubes are uniformly charged with the product. In situations, in which the liquid is not uniformly distributed among the individual tubes of the tube reactor, the results are breakdowns in the trickle phase, inhibitions in the reaction course and in the case of strong exothermic reactions local overheating, because each tube constitutes in itself a contact chamber. The

consequences are, for example, too low a degree of conversion and poor quality of the end products.

The purpose of the invention is to avoid the prior art distribution systems with respect to the drawbacks associated with tube reactors.

Therefore, the object of the invention is to provide a device for a totally uniform distribution of a liquid product among all of the tubes of a tube reactor. Furthermore, this device guarantees the formation of a uniform trickle phase, a constant reaction speed and constant heat generation in each tube.

The object is achieved with a device, which is intended for uniform distribution of a liquid among the tubes of a tube reactor and which exhibits a shower head located above a horizontally mounted distributor base, which is populated with covered distributor tubes. According to the invention, the vertically adjustable distributor tubes are provided on the upper end with an external thread and exhibit slots, which taper off from the top to the bottom and whose width at the top matches the inside diameter of the tube. Furthermore, the shower head exhibits, according to the invention, a plurality of outlet apertures.

The distributor tubes exhibit expediently a smaller diameter than the reactor tubes and project into said reactor tubes.

In order to control the outlet surface of the slots, caps are screwed on the distributor tubes. In addition, these caps also prevent the liquid splashes from penetrating directly into the distributor tubes. The slots, which taper off from the top to the bottom, in the distributor tubes make it easier to adjust to the load of the reactor.

The invention shall be explained in detail below with reference to the one embodiment and the respective drawing.

Figure 1 is a sectional view of the entire distributor system.

Figure 2 is a sectional view of the distributor tube.

In Figure 1 a reactor 1 is equipped with contact tubes 2. Above the contact tubes are located the distributor tubes 3, the inside diameter and length of which depend on the dimensions of the contact tubes. Furthermore, said distributor tubes are mounted so as to be vertically adjustable in a distributor base 4. Said distributor tubes have preferably an inside diameter ranging from 10 to 30 mm and a length ranging from 100 to 250 mm. The upper end of the distributor tubes exhibits slots 5, the depth of which ranges from 25 to 40 mm and the width of which at the top matches the inside diameter of the distributor tube. Downwardly tapering, the slots exhibit a width ranging from 2 to 4 mm. Screwed on the distributor tubes 3 are caps 6, the length of which ranges from 20 to 30 mm. Said caps are secured with setscrews 7 so as not to shift by themselves.

The product feed takes place over the feed line 8 and the shower head 9, which is made of an outwards convex baffle plate, which exhibits about 500 to 1,000 boreholes 10, the diameter of which ranges from 1 to 5 mm. Such a plurality of small outlet apertures is necessary so that the delivered liquid is distributed in thin jets over the entire cross section. In this way the surface of the liquid is prevented from swirling up.

Figure 2 shows a distributor tube in detail. The length of the thread 11 at the top end of the tube ranges from 40 to 90 mm, depending on the tube length. The size of the slot 5 may be reduced by screwing on the cap 6. The distributor tube may be mounted stationarily on the distributor base 4 with a lock nut. In addition to the overall high flexibility of the distribution system, the screw-in process, as compared to the weld-in process, of the distributor tubes offers the advantage that the tubes can be mounted exactly perpendicularly and are not subject to distortion, which occurs during the welding process.

In order to determine the effect as well as the loading capacity of the distribution system, it was tested in a tube reactor while conducting catalytic hydrogenating reactions. In so doing, the number of distributor tubes was 100; the inside diameter of the distributor tubes was 10 mm; the length of the distributor tubes was 180 mm; the slot depth was 32 mm; the length of the screw caps was 25 mm. In this case, the shower head

exhibited 700 boreholes; and the load was varied between 2 and 10 m³ / hour of product. In the throughflow test with water and various organic liquids, it was possible to achieve after repeated balancing a liquid level on the distributor base as a function of the load and the tube height. Furthermore, the same amount of liquid overflowed in each tube. In this case the variations between the individual tubes was below 4%. The device gave satisfactory results in a hydrogenating reactor, operating for the production.

Patent Claims:

1. Device, which is intended for uniform distribution of a liquid among the tubes of a tube reactor and which exhibits a shower head located above a horizontally mounted distributor base, which is populated with covered distributor tubes, characterized in

that the vertically adjustable distributor tubes are provided with an external thread and exhibit slots, which taper off from the top to the bottom and whose width at the top matches the inside diameter of the tube; and that the shower head exhibits a plurality of outlet apertures.

2. Device, as claimed in claim 1, characterized in

that the distributor tubes exhibit a smaller diameter than the reactor tubes and project into said reactor tubes.

3. Device, as claimed in claim 1 and 2, characterized in

that caps are screwed on the distributor tubes.

1 sheet of drawings to follow.