DE1080541B - Method and device for the production of unsaturated hydrocarbons from liquid hydrocarbons - Google Patents

Description

It is known to produce unsaturated hydrocarbons through partial combustion of hydrocarbons, if appropriate with the addition of steam. The starting materials are in vapor form or in a finely atomized state, e.g. B. introduced through nozzles into the reaction chamber. The one for the split Necessary heat is generated either by burning some of the raw materials or other combustible ones Substances generated in the reaction space or in front of it in a special space.

It is also known to produce fuel gases through combustion of hydrocarbons with air or oxygen in a cylindrical combustion chamber, whereby by tangential introduction of the two reactants at a correspondingly high speed Flame ring adjacent to the wall is formed. You then spray into this ring with the addition of steam axially atomized liquid hydrocarbons. The components are intensively mixed and the desired cleavage reaction takes place.

These methods have the disadvantage that, due to the sudden mixing of the components, easily Cracking of some of the substances to be cleaved occurs on the hot wall of the reaction chamber, as a result of which Soot and coke are produced, which cause difficulties both in the reaction chamber and in the downstream equipment through deposits and blockages. In addition, this causes soot and coke formation the yield of unsaturated hydrocarbons is reduced. These disadvantages make themselves special noticeable when high-boiling hydrocarbons, e.g. B. heavy residual oils, serve as starting materials, as On the one hand, these are difficult to atomize and, on the other hand, they lead to a large extent to the formation of soot and oil coke tend.

It has now been found that these disadvantages are avoided if the liquid hydrocarbons to be cleaved are used through a tube with a free outlet into the reaction space near the inner wall and near the point of introduction oxygen or gases containing oxygen, possibly also superheated steam, Flue gases and / or return gases, introduces tangentially through a slot at high speed. The speed of these gases and the fact that the first part of the reaction space in the the hydrocarbons and the gases mentioned enter, tapers conically at the end, a vortex shedding avoided from the wall. The liquid hydrocarbons are evaporated or partially burned and the Implementation of the vapors formed initiated. The further conversion of the starting materials takes place in the second cylindrical one or advantageously widening like a diffuser and expediently continued in a cylindrical shape Part of the reaction vessel.

Method and device

for the production

of unsaturated hydrocarbons
from liquid hydrocarbons

Applicant:

Aniline & Soda Factory in Baden

Corporation,

Ludwigshafen / Rhine

Dr. Adolf Steinhofer, Ludwigshafen / Rhine,

Dr. Karl Buschmann, Neustadt an der Weinstrasse,

and Dr. Leo Unterstenhöfer, Limburgerhof (Palatinate),

have been named as inventors

This method of working avoids sudden mixing of hydrocarbons and oxygen-containing ones Gases, which occurs in the known cases and to the mentioned disturbances due to coke formation leads. The speed that is necessary to detach the vortex of oxygen-containing gases from the Inner wall in the first part of the reaction space and thus an undesirably rapid mixing with the Avoiding hydrocarbons can easily be determined empirically. The effect of the different speeds can be clearly seen from those distributed over the length and cross section of the reaction vessel Temperature measuring points. It can also be determined by determining the oxygen content in the various Observe gas samples taken from places and through the clearly visible coke deposits at low gas velocity.

The gas velocity of the oxygen-containing gases is always greater than that of the hydrocarbons, expediently more than 80 m / sec, advantageously 100 to 200 m / sec. This forms near the axis of the reaction vessel a vacuum chamber into which the majority of the evaporated hydrocarbons are drawn will.

The liquid starting materials, like the oxygen-containing gases, can flow in tangentially, one can however, they can also be introduced radially or axially parallel in the vicinity of the inner wall of the reaction vessel. That The method has the advantage that you can also use heavy hydrocarbon mixtures, for example, distillation residues a viscosity of 100 ° E at 100 ° C, without coke and

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Can handle soot formation. Since you have a device rangsrohr 7 with free outlet flows with a low

not required for evaporation and atomization, an overpressure of 500 to 1000 mm water column creates a petroleum fraction

This opens up a new way to split the high and medium boiling range into channel 6 and from there into

boiling, difficult to vaporize or atomize reaction space 1, where it is caused by the kinetic energy

oily residues. 5 of the gaseous or vaporous substances to form a film

It has already been proposed that acetylene and the inner wall of the reaction vessel is expanded. Ethylene is produced in such a way that coal The oil evaporates on the wall of the fuel gas, hydrogen in gaseous or vapor form through the middle of a preheated reaction vessel that was supplied through 9 and another from a coal vessel. While a part of the oil vapors is burned to cover the hydrogen and / or air existing gas stream io gap heat, the main part enters the tangential and between the vessel wall and near the axis of the reaction vessel,
the middle gas flow passes through the reaction chamber. In order to prevent a sudden, intensive mixing of the In this mode of operation, in which the hydrocarbons reactants are introduced in part 2 of the reaction vessel in liquid form and do not form a film, the transition from part 1 to part 2 takes place through nozzles which are dangerous From Ver 15 the conical intermediate piece 10 is made with such a conical plugging and the angles are difficult for processing that a reduction in the Umgangsgeschwin oils are useless at all. the circulating gases and vapors in the desired

The course of the split is as follows: The extent to be split occurs without a disturbing turbulence

Tending liquid hydrocarbon mixture is done by means of the whole mixture. The cone angle is

oxygen, optionally mixed with water vapor, advantageously less than 10 °.

The part 2 of the reaction chamber is cylindrical, like a band spread out on the chamber wall, but it can also be wholly or partially conical, and the evaporation takes place from it. To be led with a high level of guidance. By the cooling speed sprayed in at 11 along the cylindrical wall, the reaction is generated in a known manner under a water vapor-oxygen mixture which breaks axially in order to prevent decomposition of the products. Vacuum area into which the vaporous coal part of the reaction space is drawn with heat-resistant hydrogen. Lined with material along the way. It is expedient to arrange channels to the reaction chamber thanks to the aforementioned preheating of the oxygen-containing gases on its structural measures with decreasing twist. The remaining part of the reaction mixing of oxygen and optionally the vessel can also be completely or partially lined with heat-water vapor with the hydrocarbons, with a resistant material,
continuous partial combustion occurs. Correspondingly, the speed of the introduced in channel 6 increases the temperature of the reaction mixture on the gases and vapors depending on the exit path to be split through the reaction space and only reaches the desired splitting end cross-section on the substance through exchangeable inserts with different ends of the reaction space can be set optionally. By the temperature. Door 12 at one end of the reaction vessel is possible

Fig. 1 shows the temperature profile in the reaction Hch, the film formation, ignition, etc. to be observed,
chamber again. This process in the reaction chamber is easily detectable analytically with ordinary or weak. In the first third increased pressure, for example 2at, carried out; However, higher pressures can also be used in the reaction space near the wall, whereby zones mainly oxygen at low initial temperatures, the hydrogenating effect of the hydrogen formed, which is promoted according to the increasing acidic reaction space. To increase this decrease in substance, increase slowly. In the interior, on the other hand, you can add hydrogen or hydrogen, which are still unchanged hydrocarbons, sustainable gases.

assignable. In the mixing zone, in which, as a result of the constant 45 Dj _e, the resulting fission gases are cooled in

decreasing twist the mixing and implementation in the known manner by water, but it can also

outside rotating water vapor-oxygen layer with done by putting gas in a nozzle or under

the hydrocarbons located in the vicinity of the axis - work gain relaxed,
follows are carbon monoxide, hydrogen, olefins, and methane.

detectable. In the last quarter of the reaction chamber 50 example

one meets in the zone of equilibrium temperature in a reaction vessel according to Fig. 2, which has an overall uniform final composition of the cracked gas. length of 2400 mm and in the non-constricted part This course also explains why no coke formation has a diameter of 350 mm if it is allowed to take place per hour on the chamber walls. The hydrocarbon 95 kg light petrol with a boiling range of up to 105 ° C gradually reacts from the inside with 55 running in. At the same time, the reaction vessel is supplied with the oxygen-water rotating rapidly along the wall - 0.282 Nm ^{3 of} oxygen and 0.525 kg of steam mixture per kg of light gasoline with a continuous rise in temperature - water vapor. The cracking temperature at the end is so that it is not at all possible for the uncleaved reaction space to reach 725 ° C. The cracking gas emerging from the reaction to a hot wall space is cooled with water. It get there and lead to coke deposits. At ⁵ ° has the following composition in percentage by volume:
At the end of the reaction chamber, the fission gases are quenched with water in a known manner. CO ₂ , 2.8%

An example embodiment of the process C ₃ H ₆ and higher hydrocarbons 10.6%

is explained on the basis of Fig. 2. In the part 1 of a C ₂ H ₂ , 0, S%

cylindrical reaction vessel with a 65 C ₂ H ₄ , 21.1%

conical constriction, is by, the slot 3 H ₂ 8.8%

a mixture of oxygen and water vapor with a CO., 33.4%

Speed of 100 to 200 m / sec from the pipes 4 C ₂ H ₆ and higher hydrocarbons., 5, Ό%

and 5 and the channel 6 inserted. By a rigid CH ₄ , 17.6%

or height-adjustable swiveling feeder 7o Q ₂ and N ₂ tracks

The upper calorific value is 9580 kcal. The total yield of olefins is 0.42 kg / kg introduced Light petrol.

Claims (2)

Patent claims: 1. A process for the production of unsaturated hydrocarbons from liquid hydrocarbons, characterized in that the starting materials are introduced through a tube (7) with a free outlet into the first cylindrical part of a reaction vessel near the inner wall, near the point of introduction of oxygen or gases containing oxygen, optionally also superheated steam, flue gases and / or return gases, introduces tangentially through a slot (3) at high speed, where ■ by the speed of these gases and by, ■ that the first part of the reaction chamber (1), in which the hydrocarbons and the The gases mentioned enter, tapers conically at the end, vortex shedding from the wall is avoided and the reaction in the second cylindrical or advantageously diffuser-like expanding (10) and then expediently cylindrical (2) part of the reaction vessel is completed. 2. Apparatus for performing the method according to claim 1, consisting of a reaction vessel whose first cylindrical part (1) into which the Starting materials and the oxygen-containing and optionally other gases mentioned occur on The end is tapered and its second part (2) by a conical intermediate piece (10) with a cone angle is connected to the first part by a maximum of 10 °. Considered publications:
U.S. Patent No. 2,377,245. 1 sheet of drawings © 009 507/421 4.