DE1009615B - Process for the flameless conversion of gaseous or vaporous hydrocarbons to olefins - Google Patents

Description

GERMAN

It is known that gaseous or vaporous hydrocarbons having at least 2 carbon atoms can be used in the molecule in the same way with oxygen or containing oxygen «! Can convert gases that you can Mixes gases in a mixer and then puts them in a room with fixed inert substances leads, in which they are converted to a peak temperature. Another procedure exists in that the gases enter a fluidized bed chamber filled with inert solids after mixing and react there at constant temperature.

It has been shown that this is the only way to avoid flame formation at the mixing point in this process can be that the gas application of the fixed or moving masses of the reaction space holds relatively high. At lower gas velocities, the advantage is that less high pressure losses occur in the mixing zone slightly a sooty stationary flame.

It has now been found that the reaction of gaseous hydrocarbons is complete Combustion of insufficient amounts of oxygen to form olefins within wide limits of the gas application safely avoiding a lingering flame if one is in front of the Mixing the gases to the oxygen-containing gas supplies water vapor in such an amount that one by ignition Flame arising at the mixing point is carried out of the mixing device and extinguished.

The amounts of water vapor to be added to the oxygen-containing gas can be determined as a function of determine the selected gas load in a simple manner by means of preliminary tests. Bring the hydrocarbon-containing one Gas and the oxygen-containing gas in the given mixing device initially without water vapor together. If you ignite, a permanent flame is formed. By gradually adding steam The amount of water vapor required for extinguishing can now be determined for the oxygen-containing gas the flames is required. Surprisingly, it has been shown that even with simple mixing devices, in which the gases to be mixed do not suffer too great a pressure loss, within further Limits of the gas application with relatively small amounts of water vapor the formation of a permanent flame is avoided with certainty.

It is also possible to mix water vapor with the hydrocarbon-containing gas. It was observed that Occasional pre-reactions at the mixing point occur considerably less often when the hydrocarbon-containing Gas contains, for example, 1 to 6 percent by volume of water vapor. However, that carries the hydrocarbonaceous Water vapor admixed with the gas practically does not contribute to the formation of a stationary one

Method of flameless implementation

of gaseous or vaporous
Hydrocarbons to olefins

Applicant:

Aniline & Soda Factory in Baden
Aktiengesellschaft, Ludwigshafen / Rhein

Dr. Ernst Bartholome, Heidelberg,
Dr. Alfred Helms and Dr. Helmut Nonnenmacher,

Ludwigshafen / Rhine,
have been named as inventors

To prevent flame in the event of pre-ignition. Therefore, preference must be given to water vapor add to the oxygen-containing gas.

One works among those for the splitting of hydrocarbons by partial combustion with oxygen known conditions, e.g. B. at temperatures from 600 to 1000 °, at normal, increased or also reduced pressure. Suitable as inert solids in particular artificial or natural heat-resistant silicates. Primarily one becomes one Select substances as fluidized material whose abrasion is as low as possible.

ο · 1

example

In a fluidized bed chamber with a clear width of 90 cm and a fluidized bed height of about 60 cm, every hour 120 Nm ³ propane with 51 Nm ³ oxygen in whirling-r moving fine-grained silimannite at a reaction temperature of about 795 ° and normal pressure to one a thy! soften cracked gas implemented. The gases are preheated separately to 600 ° and in.

a device consisting of two concentric tubes, the inner, shorter tube the oxygen supply is used, while the propane through the annular space formed by the two tubes flows in.

If oxygen is used without the addition of water vapor, it is observed that occasional preignitions lead to a sticking flame in the mixing device. Duirch makes preliminary tests one finds that occasional preliminary reactions in the

709 547/416

Claims (15)

3 4 Mixing apparatus can then be carried out from this.
den when the oxygen is at least the same Amount of steam, ^{calculated as Nm 3} , is added. 1. Method for the flameless implementation of Under these conditions it is possible to use gaseous or vaporous hydrocarbons safe without forming a stationary flame in the 5 having at least 2 carbon atoms in the molecule Mixing device to work. Insufficient in the mixing device for complete combustion tion, the propane flowing into the annulus suffers amounts of oxygen at high temperatures of a pressure loss of less than half about 600 to 1000 ° for the extraction of gaseous Meters of water, the olefins flowing in the inner tube, with the gases entering the Mixture of oxygen and water vapor can be mixed in a reaction furnace, thereby identifying Pressure loss of less than one meter of water shows that before the gases mix pillar. Oxygen-containing gas water vapor in An hourly 285 Nm ^{3 of} cracked gas is obtained in the following amount that one is supplied by ignition the composition in percent by volume: at the mixing point occurring flame from the 15 mixing device is carried out, and the Carbon dioxide l, b _{gases in a} fluidized bed of granular solid Ethylene converts 23.0 substances. Propylene 7.6 ₂ _ The method _{according to} claim 1, characterized in Carbon monoxide 17.4 distinguishes that also the hydrocarbons Hydrogen 19.1 _{20 Wassmiamp £} is added. Methane and homologues 30.0 3 _{Method according to claim 2} , characterized in that Mickstott U> 1 records that the oxygen-containing gas in baiuearstott U, A calculated by volume, more water vapor The proportion of methane homologues is low. holds as the gas containing hydrocarbons. © 709 547/418 5.57