Method for producing acetylene and syngas

Patent metadata

Field	Value
Publication number	US-11459281-B2
Application number	US-201917048342-A
Country	US
Kind code	B2
Filing date	Apr 8, 2019
Priority date	Apr 17, 2018
Publication date	Oct 4, 2022
Grant date	Oct 4, 2022

Abstract

A process for producing acetylene and syngas by partial oxidation of hydrocarbons with oxygen, involving: separately preheating a hydrocarbon and a oxygen-comprising input stream; mixing in a mass flow ratio of the oxygen-comprising to hydrocarbon stream at an oxygen number no more than 0.31; feeding the streams via a burner block to a combustion chamber and therein partially oxidizing the hydrocarbon(s) to a cracking gas; quenching the cracking gas to 80 to 90° C. downstream by injecting an aqueous quench medium to obtain a process water stream- 1 and a product gas stream- 2 ; cooling the product gas stream- 2 in a cooling column by direct heat exchange with cooling water to obtain a process water stream- 2 as bottoms, a product gas stream- 2 as uppers, and a sidestream; and depleting the sidestream of soot in an electrofilter to generate therein a process water stream- 3 combined with water streams- 1/2 to afford the process water stream- 4.

First claim

The invention claimed is:

1. A process for producing acetylene and synthesis gas by partial oxidation of one or more hydrocarbons with oxygen, the process comprising:
separately preheating a first input stream comprising a hydrocarbon and a second oxygen-comprising input stream;
mixing the first and second streams in a mass flow ratio of the second to the first input stream at an oxygen number of not more than 0.31, the oxygen number meaning a ratio of an oxygen amount actually present in the second input stream to the stoichiometrically necessary oxygen amount required for complete combustion of hydrocarbons in the first input stream, to obtain a mixed stream;
feeding the mixed stream via a burner block to a combustion chamber in which the hydrocarbons are partially oxidized, thereby obtaining a cracking gas comprising the acetylene and the synthesis gas;
quenching the cracking gas to a temperature in a range of from 80 to 90° C. downstream of the combustion chamber by injection of an aqueous quench medium to obtain a first process water stream I liq and a first product gas stream I g ;
cooling the first product gas stream in a cooling column by direct heat exchange with cooling water to obtain a second process water stream II liq , as a bottom stream, a second product gas stream II g , as a top stream, and a sidestream;
depleting the sidestream of soot in an electrofilter to generate in the electrofilter a third process water stream II liq , which is combined with the first and second process water streams I liq and II liq to afford a fourth process water stream IV liq ,
purifying the fourth process water stream IV liq by partial evaporation in a decompression vessel, wherein the fourth process water stream IV liq is evaporated in a proportion in a range of from 0.01 to 10 wt. % based on total fourth process water stream weight to obtain a purified fifth process water stream V liq ;
withdrawing the purified fifth process water stream V liq at a bottom of the decompression vessel and passing the purified fifth process water stream V liq through one or more soot channels comprising surface particle separators to obtain a sixth process water stream VI liq freed of floating soot; and
recycling the sixth process water stream VI liq into the process.

2. The process of claim 1 , wherein the sixth process water stream VI liq is completely recycled into the process.

3. The process of claim 1 , further comprising:
dividing up the sixth process water stream VI liq exiting the soot channels into
a first water substream, which is supplied as a seventh process water stream VII liq to a cooling tower and cooled therein and subsequently recycled into the cooling column, and
a second water substream, which is recycled as an eighth process water stream VIII liq into a quench region below the burner block.

4. The process of claim 1 , further comprising:
dividing up the sixth process water stream VI liq exiting the soot channels into
a first water substream, which is supplied to a heat exchanger as a seventh process water stream VII liq and, after cooling, obtaining a cooled substream, the cooled substream being recycled into the cooling column and a remaining substream being discharged into a wastewater, and
a second water substream exiting the soot channels, which is recycled into a quench region below the burner block as an eighth process water stream VIII liq .

5. The process of claim 1 , wherein the fourth process water stream IV liq is evaporated in a proportion in a range of from 0.5 to 5 wt. % based on the total fourth process water stream weight.

6. The process of claim 1 , wherein the partial evaporation is carried out by decompression into vacuum.

7. The process of claim 1 , wherein the partial evaporation is carried out by decompression into a vacuum in a range of from 50 to 900 mbar a.

8. The process of claim 1 , wherein the partial evaporation is carried out by decompression into a vacuum in a range of from 200 to 600 mbar a.

9. The process of claim 1 , wherein the partial evaporation is carried out by adiabatic decompression.

10. The process of claim 1 , wherein the partial evaporation is assisted by heating.

11. The process of claim 10 , wherein the heating is carried out by direct steam injection.

12. The process of claim 1 , wherein the first input stream comprises natural gas.

Assignees

• Basf Se

Inventors

• Vicari Maximilian
• Weichert Christian
• Anderlohr Christopher Alec
• Reif Wolfgang

Classifications

• C01B3/36

  using oxygen; using mixtures containing oxygen as gasifying agents · CPC title

• C01B2203/048

  the impurity being an organic compound · CPC title

• C07C2/78 Primary

  Processes with partial combustion · CPC title

• C01B2203/049

  the impurity being carbon · CPC title

• C01B2203/0877

  by direct injection of fluid · CPC title