Installation and method for producing and disaggregating synthesis gases from natural gas

• US 20050107480A1
• Filed: 03/22/2003
• Published: 05/19/2005
• Est. Priority Date: 06/13/2002
• Status: Active Grant

• Current Assignee: Lurgi AG (Air Liquide SA)
• Original Assignee: Lurgi AG (Air Liquide SA)
• Inventors: Meyer, Manfred, Davey, William
• Granted Patent: US 7,183,326 B2
• Time in Patent Office: Days
• US Class Current: 518/726
• CPC Class Codes: C01B 2203/0227 containing a catalytic reforming step
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/0288 containing two CO-shift steps
• CPC Class Codes: C01B 2203/0415 Purification by absorption in liquids
• CPC Class Codes: C01B 2203/0465 Composition of the impurity
• CPC Class Codes: C01B 2203/047 the impurity being carbon monoxide
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 2203/048 the impurity being an organic compound
• CPC Class Codes: C01B 2203/0485 the impurity being a sulfur compound
• CPC Class Codes: C01B 2203/061 Methanol production
• CPC Class Codes: C01B 2203/068 Ammonia synthesis
• CPC Class Codes: C01B 3/025 Preparation or purification of gas mixtures for ammonia synthesis
• CPC Class Codes: C01B 3/506 at low temperatures
• CPC Class Codes: C01B 3/52 by contacting with liquids; Regeneration of used liquids C01B3/508 takes precedence
• CPC Class Codes: C07C 29/1518 one step being the formation of initial mixture of carbon oxides and hydrogen for synthesis
• CPC Class Codes: C07C 29/152 characterised by the reactor used
• CPC Class Codes: C07C 31/04 Methanol
• CPC Class Codes: F25J 2200/70 Refluxing the column with a condensed part of the feed stream, i.e. fractionator top is stripped or self-rectified
• CPC Class Codes: F25J 2205/04 in the feed line, i.e. upstream of the fractionation step
• CPC Class Codes: F25J 2205/30 using a washing, e.g. "scrubbing" or bubble column for purification purposes
• CPC Class Codes: F25J 2205/40 : using hybrid system, i.e. combining cryogenic and non-cryogenic separation techniques
• CPC Class Codes: F25J 2205/60 : using adsorption on solid adsorbents, e.g. by temperature-swing adsorption [TSA] at the hot or cold end
• CPC Class Codes: F25J 2210/42 : Nitrogen
• CPC Class Codes: F25J 2215/02 : Mixing or blending of fluids to yield a certain product
• CPC Class Codes: F25J 2230/30 : Compression of the feed stream
• CPC Class Codes: F25J 2270/02 : Internal refrigeration with liquid vaporising loop
• CPC Class Codes: F25J 3/0223 : H2/CO mixtures, i.e. synthesis gas; Water gas or shifted synthesis gas production of carbon monoxide containing gas in general C01B32/40, C10J, C10K; production of hydrogen containing gas C01B3/00
• CPC Class Codes: F25J 3/0261 : separation of carbon monoxide production of carbon monoxide containing gas in general C01B32/40, C10J, C10K
• CPC Class Codes: F25J 3/0271 : separation of H2/CO mixtures, i.e. of synthesis gas production of carbon monoxide containing gas in general C01B32/40, C10J, C10K, production of hydrogen containing gas C01B3/00
• CPC Class Codes: F25J 3/0276 : separation of H2/N2 mixtures, i.e. of ammonia synthesis gas in general C01B3/00
• CPC Class Codes: F25J 3/04539 : for the H2/CO synthesis by partial oxidation or oxygen consuming reforming processes of fuels
• CPC Class Codes: F25J 3/04587 : for the NH3 synthesis, e.g. for adjusting the H2/N2 ratio
• CPC Class Codes: Y02P 20/151 : Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

What is described is a method and an installation for the simultaneous production of methanol synthesis gas, ammonia synthesis gas, carbon monoxide and carbon dioxide from natural gas, in which several plant elements (or plant units) are serially arranged one by one in one single production chain, whereat these elements comprise: a first reactor A, in which the natural gas is transformed under oxygen supply into a synthesis gas mixture comprised of carbon monoxide, carbon dioxide, hydrogen and steam (water vapour), a second reactor B, which allows to control the transformation of carbon monoxide into carbon dioxide, optionally a compressor C for compressing the generated gases, an absorber D for the absorption of carbon dioxide and for obtaining the carbon monoxide-hydrogen mixture used for methanol synthesis, a low-temperature separator E, in which ammonia synthesis gas is obtained by introducing liquid nitrogen, and in which simultaneously carbon monoxide, argon and methane are removed.

Claims

1. Installation for the simultaneous production of methanol synthesis gas, ammonia synthesis gas, carbon monoxide and carbon dioxide from natural gas, characterised in that several plant elements are serially arranged one by one in one single production chain, whereat these elements comprise:

a first reactor A, in which the natural gas is transformed under oxygen supply into a synthesis gas mixture comprised of carbon monoxide, carbon dioxide, hydrogen and steam (water vapour),

a second reactor B, which allows to control the transformation of carbon monoxide into carbon dioxide,

an absorber D for the absorption of carbon dioxide and for obtaining the carbon monoxide-hydrogen mixture used for methanol synthesis,

a low-temperature separator E, in which ammonia synthesis gas is obtained by introducing liquid nitrogen, and in which simultaneously carbon monoxide, argon and methane are removed.

2. Installation according to claim 1, characterised in that a compressor C is provided, in which the gases generated in reactors A and B can be compressed.

3. Installation according to claim 1, characterised in that the reactor A exhibits feed lines for natural gas, steam and oxygen in order to accomplish a catalytic partial oxidation of the natural gas.

4. Installation according to claim 1, characterised in that the second reactor exhibits a bypass, via which the synthesis gas mixture obtained in reactor A can be entirely or partially guided past said reactor B, thus allowing to control the degree of oxidation of the synthesis gas mixture, in particular the generation of carbon dioxide from carbon monoxide.

5. Installation according to claim 2, characterised in that a compressor C is provided, by which the gas pressure can be adjusted to a value assuring the physical or chemical absorption of carbon dioxide in the absorber D.

6. Installation according to claim 1, characterised in that the absorber D exhibits a feed line for the synthesis gas mixture and discharge lines for the methanol synthesis gas being comprised of carbon monoxide and hydrogen, for carbon dioxide and for the synthesis gas being purified of carbon dioxide and as well as for gases being suitable for other syntheses and having the respective appropriate compositions.

7. Installation according to claim 1 characterised in that the low temperature separator E exhibits feed lines for the synthesis gas being purified of carbon dioxide and for liquid nitrogen and discharge lines for the ammonia synthesis gas, for pure carbon monoxide, for a fuel gas containing methane, argon and carbon monoxide and for a fluid containing carbon monoxide and hydrogen.

8. Method for the simultaneous production of methanol synthesis gas, ammonia synthesis gas, carbon monoxide and carbon dioxide from natural gas by introducing steam (water vapour) and oxygen into a plant according to claim 1, characterised in that in the first reactor the molar ratio of steam to non-oxidised hydrocarbons is 1.5 up to 3.0, preferably 1.7.

9. Method according to claim 8, characterised in that in the first reactor the molar ratio of oxygen to non-oxidised hydrocarbons is 0.45 up to 0.7, preferably 0.52.

10. Method according to claim 8, characterised in that a catalyst containing nickel oxide is used for transforming the natural gas into a synthesis gas.

11. Method according to claim 8, characterised in that for transforming the natural gas into a synthesis gas, a pressure of 25 to 100 bar, preferably a pressure of about 40 bar, is used.

12. Method according to claim 8, characterised in that for the oxidation of carbon monoxide to carbon dioxide in the second reactor B, a one- or two-step method with intermediate cooling in the presence of high temperature catalysts is performed.

13. Method according to claim 8, characterised in that the synthesis gas produced in the reactors A and B is adjusted by means of the compressor C to a pressure of 60 to 100 bar, preferably of 80 bar.

14. Method according to claim 8, characterised in that in the absorber D the carbon dioxide is separated from the synthesis gas in one or more process steps in a chemical or physical way.

15. Method according to claim 8, characterised in that the synthesis gas is cooled off to temperatures of −

150°

C. to −

200°

C. in the separator by introducing liquid nitrogen and that thereby methane, argon and carbon monoxide are removed and that the remaining hydrogen gas is mixed with nitrogen in a molar ratio of 3;

1 in order to obtain ammonia synthesis gas.