DE2058553B2 - Device for the production of low molecular weight olefins - Google Patents

Description

The invention relates to an apparatus for the production of low molecular weight olefins by continuous thermal cracking of more saturated hydrocarbons in a bath of molten Metal with a decomposition chamber, in the lower part of which is a pipe for introducing hydrocarbons opens and the top is provided with an outlet for the resulting product is and with a heating chamber into which a pipe for introducing the heating gas in the lower area opens and which has an outlet at the top for discharging the combustion gas.

Such a device is known from US Pat. No. 3,081,256. The known device has a relatively complex structure and requires a relatively large amount of molten material Salts or metals.

The object of the invention is therefore to provide a compact, simply constructed device of the type mentioned at the beginning Kind to create with good efficiency.

According to the invention, this object is achieved by a device of the type mentioned at the outset, which is characterized in that the decomposition chamber and the heating chamber each with one in the upper The area ending overflow weir and an overflow department adjacent to the overflow weir are that on the underside crosswise with the underside of the heating or disintegration chamber in connection place.

According to the invention there is an advantageous gas lift effect by blowing a hydrocarbon gas as a raw material into the decomposition chamber and of a combustion gas is generated in the heating chamber of a heating means.

The amount of the heating agent and the temperature can vary according to the kind of the to be decomposed Raw hydrocarbon can be selected. The hydrocarbon material preferably becomes gaseous blown into the molten metal of the decomposition chamber and heated there. The raw gas comes violently in contact with the hot, molten metal or salt and is quickly heated up and decomposed. The outflow velocity of the injected gas or the decomposed gas from the The size of the decomposition chamber must be such that the heating medium is not entrained with the gas is, however, the decomposed gas does not remain in the decomposition chamber so long that a chemical Reaction takes place.

In the decomposition chamber, the heating means occupies a foam of decomposed gas, so that the specific weight of the heating medium decreases and this rises upwards. The heating medium is from separated from the decomposed gas on the liquid surface and flows over the overflow weir. The overflowing Heating medium then falls down into the overflow compartment and passes through the connecting passage at the bottom into the lower part of the heating chamber one. The heat extracted in the decomposition chamber is converted into the heating chamber by hot combustion gases fed back.

In this case it is advantageous that the combustion gas contains a small proportion of air, so that

with the heating agent is not oxidized. The gas lift effect that occurs in the heating chamber by blowing it in of the combustion gas is caused, lets the heating medium from the heating chamber into the same Cross overflow compartment in the same way as the decomposition chamber. The heating medium then flows back into the decomposition chamber through the passage at the bottom.

In the following, for example, preferred embodiments of the invention are based on the Drawing explained in more detail.

F i g. 1 is a vertical section of an embodiment of a device according to the invention for Decomposition of hydrocarbons;

Fig. 2 shows a plan view corresponding to Fig. 1, with the top portion removed;

F i g. Figure 3 is a plan view of another embodiment of the invention in which decomposition chambers are provided on either side of the heating chamber are;

so F i g. 4 is a section on the right-hand side along the line AA and on the left-hand side along the line BB in FIG. 3;

F i g. 5 shows a plan view of a further, circularly shaped embodiment of the invention; F i g. 6 is a partially sectioned view of the right side of this device, on the left along line DD, on the right along line EE of FIG. 5.

According to FIG. 1 and 2, the device according to the invention has a housing Γ for a bath that from an outer wall 1 made of profile-reinforced steel plates, a lining layer 2 made of heat-insulating Bricks and an inner, heat-insulating brick layer 3 consists. A downward

f'5 running partition 4 is provided in the middle of the housing C and divides the housing into a decomposition chamber 14 and a heating chamber 15. Communication passages 12 and 13 are between the

lower end of the partition 4 and the lower Beform according to FIG. 1 and 2. Correspondingly 11 of the housing C are provided. An upwards before parts are denoted by the same reference numerals. When the overflow weir 5 is in the decomposition section of this embodiment, the molten measuring chamber 14 is arranged and divides the decomposition metal circulated in the same way,
mer 14 into a reaction compartment 16 and an over- 5 The embodiment according to FIG. 5 and 6 shows running compartment 17. A similar overflow weir 6 is in an example of a decomposition chamber 14, which is attached to and divides the heating chamber 15 in a shape around the heating chamber 15, heating chamber into a heating compartment 18 and an overflow and substantially with the embodiment after running department 19. Fig. 1 and 2 coincide. Here, too, are the same

The overflow compartments 17 and 19 are offset io parts with the same reference numerals,
arranged as shown in FIG. 2 is shown. In this embodiment, an overflow drainage compartment 17 communicates with the hay compartment 18 via partition 19 around a circular heating compartment 18, the connecting passage 12 below the overflow, into which the combustion gas compartment 19 communicates. The overflow department 19 is blown. An overflow compartment 17 and an is connected to the reaction compartment 16 via a connection 15 area into which the gas to be decomposed is blown through passage 13 below the overflow compartment 17 are connected through the decomposition chamber 14. The reaction compartment 16 into which the overflow compartment 19 is formed. When the decomposing gas is blown in, four gas blower pipes 7 are equipped with a suitable number of gas blower pipes 7, and for combustion gas at an angle of 90 °, the heating compartment 18, into which the combustion gas starts, is provided in one embodiment Connection passage part is blown is also of a suitable number and 13 are each provided in four places as provided by gas blowing pipes 9. Furthermore, it is an issue that the molten metal can circulate to the desired outlet pipe 8 for the decomposed gases above the decomposition and above-described type. The settlement chamber 14 and an outlet pipe 10 for the number of these arrangements and elements can be varied depending on the combustion gases above the heating chamber 15, but as desired,
orderly. The following examples serve to further

In operation, a combustion gas is used in the gas.
Substance gas is blown into the gas blower pipes 7. The gas
flows relatively uniformly out of small openings 30
of the gas blow tube 7. The gas is carried by the molten metal, preferably ^ asmelted lead,

warmed and decomposed. At the same time, example 1 flows

Molten metal in the reaction compartment 16 due to the foam formation through the gas blowing tube 7 upwards, and the liquid level L ₁ occurs

over the top of the overflow weir 5. As a result, ethylene, propylene and butylene are made from n-butane the molten metal flows into the overflow section using the apparatus of FIG. 1 ment 17. On the other hand, the decomposed gas is produced by and 2. The device was 1720 mm the outlet pipe 8 withdrawn. At this point 40 wide, 400 mm deep and 1200 mm high. 3500 kg of spirit the decomposed gas from the drops of molten-molten lead were used as heating means, zenen metal in the upper part of the decomposition chamber Propane served as combustion gas and was through 14 has been separated so that the molten metal has a 3 mm diameter opening through the gas layer is entrained through the outlet pipe 8. blowpipe 9 initiated. The throughput was 4.5 kg / h.

The molten metal in the training section 45 The molten lead in the bath was heated to 880 to 17 flowing through the communication passage 12 to the 930 ° C. The η-butane was in the melted heating section 18. _zene lead with a throughput of 30 kg / h through the

Into the heating compartment 18 is introduced through the gas blowing gas blowing pipe 7. The combustion gas blown in through the gas exhaust pipe 9 so that the gas exiting the vent pipe 8 was analyzed and the molten metal was heated. The melted 50 has the following composition:
Metal in the heating compartment 18 flows over the overflow weir into the overflow compartment 19 as the liquid level L _{2 is raised} in the same manner as in the decomposition chamber. On the other hand, the table 1
Combustion gas discharged through the outlet pipe 10
pulled. The molten metal from the transfer section 19 flows through the other communication passage 13 which is adjacent to the communication passage
12 is provided into the reaction compartment 16. This repeats the above-mentioned movement. 60
The molten metal is successively through
rooms 16, 17, 12, 18, 19, 13 and 16 are circulated,
and decomposition occurs during the agitation
of the gas.

The in F i g. The device shown in FIGS. 3 and 4 is numbered 65 Decomposition chambers 14 are provided, which are arranged on both sides of the heating chamber 15. Tm rest ordered compliance with the execution

Part of the gas Volume percentage H ₁ , 15.1
26.4
0.5 CH ₁ 30.9
3.2 C ₁ H, 10.8
1.3
11.8 CH, 100.0 CH ₁₁ C ₁ H. C ₁ H, C ₁ H _1n total

Example 2

Part of the gas First
sample 'olumproze
Second
sample nt
third
sample H, 10.2 12.9 14.4 CH, 25.8 29.3 20.2 CH, 29.1
4.6 30.0
2.3 33.3
3.6 2 4 10.7 8.5 10.1 CH _n 1.7
3.6 1.2
3.2 0.6
2.5 3 * β 1.0 0.8 0.9 C ₁ HL 13.3 11.8 14.4 100.0 100.0 100.0 Higher hydrocarbons
fabrics total

Table 3

Molten lead temperature

Tn a device according to FIGS. 1 and 2 was Gasoline decomposes. The gasoline had a boiling range from 45 to 100 ° C. As a heating medium was molten lead as used in Example 1. Propane was also used as heating gas, through which a tem- »ο Η, temperature of 800 to 910 ° C was achieved. The gasoline was introduced with a throughput of 60 kg / h. The resulting product had the following composition:

Table 2

Part of the
Gas *)

910 ⁰ C

Fourth rehearsal

Total 100.0 100.0 100.0 100.0

*) The percentage of each component was calculated! on the entire volume of the non-condensing product.

The amount of condensing product was 46 percent by weight based on the original entered gasoline with molten lead before 765 ° C 9 percent by weight at a lead temperature from 910 ° C.

The composition of the condensing product is shown in Table 4.

Table 4

Composition of the condensing product *)

35

Example 3

benzene

toluene

Xylene and ethylbenzene

Gasoline was decomposed in the same manner as in Example 2 Styrene, however gasoline was mixed with a Siedebe- 40 q ranging from 45 to 200 ° C is used, and the temperature of the molten lead naphthalene door was in one case to 765 ° C, in the other Changed trap to 910 ° C. In both cases the gasoline was introduced with a throughput of 80 kg / h. The components of the resulting gas product are shown in Table 3 below.

Heavier components than
Naphthalene

total

Weight percent

16 9

22nd

10.5

17.5

100.0

*) Weight percent of each component, based on

Condensation reaction product.

1 sheet of drawings

Claims (1)

Claim: Apparatus for the production of low molecular weight olefins by continuous thermal Breakdown of more saturated hydrocarbons in a bath of molten salt or molten metal with a decomposition chamber, in the lower part of which is a pipe for introducing hydrocarbons opens and that at the top with an outlet for the resulting product is provided, and with a heating chamber in the lower area Tube for introducing a heating gas opens and the top has an outlet for draining of the combustion gas, characterized in that the decomposition chamber (14) and the heating chamber (15) each with an overflow weir (5, 6) ending in the upper area and an overflow compartment (17, 19) adjoining the overflow weir, which at the underside crosswise with the undersides of the heating or decomposition chamber (15, 14) in connection stand.