Method and apparatus for producing chemicals from a methane-containing gas
An apparatus and a method for producing chemicals from a methane-containing gas are provided. More specifically, the method and an apparatus make use of heterogeneous catalysis, beginning with the partial oxidation of methane to produce synthesis gas followed by a reaction, such as a Fischer-Tropsch reaction, to produce the chemicals.
1. An apparatus for producing chemicals from a methane-containing gas, the apparatus comprising:
a reactor comprising:
a gas input,
a reaction product output, the gas input and the reaction product output defining together a gas flow path in the reactor,
a partial oxidation reaction zone located inside the reactor downstream of the gas input, the partial oxidation reaction zone comprising a supported or unsupported partial oxidation metal catalyst, and
a Fischer-Tropsch reaction zone located inside the reactor downstream of the partial oxidation reaction zone, the Fischer-Tropsch reaction zone comprising a Fischer-Tropsch catalyst,
a methane-containing gas source feeding the methane-containing gas at a given partial pressure to the gas input, and
an air source feeding air at a given partial pressure to the gas input,
wherein, upon starting operation, the partial oxidation reaction zone is heated to start a partial oxidation reaction, and
wherein, during operation, the temperature in the partial oxidation reaction zone is controlled by variation of the partial pressure of the methane-containing gas fed to the input.
2. The apparatus of claim 1 , wherein the partial oxidation reaction zone comprises a fluidized bed of the partial oxidation metal catalyst.
3. The apparatus of claim 1 , wherein the partial oxidation reaction zone comprises a fixed bed of the partial oxidation metal catalyst.
4. The apparatus of claim 1 , wherein the partial oxidation reaction zone comprises a gauze reactor containing the partial oxidation metal catalyst.
5. The apparatus of claim 1 , wherein the Fischer-Tropsch reaction zone comprises a fluidized bed of the Fischer-Tropsch catalyst.
6. The apparatus of claim 1 , wherein the Fischer-Tropsch reaction zone comprises a fixed bed of the Fischer-Tropsch catalyst.
7. The apparatus of claim 1 , wherein, upon starting operation, the partial oxidation reaction zone is heated by burning methane in the partial oxidation reaction zone.
8. The apparatus of claim 1 , wherein, upon starting operation, the partial oxidation reaction zone is heated by a heater located downstream of the gas input and upstream of the partial oxidation reaction zone.
9. The apparatus of claim 1 , further comprising a cooling device to maintain the Fischer-Tropsch reaction zone at a temperature appropriate for reaction with the Fischer-Tropsch catalyst.
10. The apparatus of claim 9 , wherein the cooling device is cooling coils located in the Fischer-Tropsch reaction zone.
11. The apparatus of claim 9 , wherein the cooling device is a water sparger located downstream of the partial oxidation reaction zone and upstream of the Fischer-Tropsch reaction zone.
12. The apparatus of claim 1 , wherein the temperature of the Fischer-Tropsch reaction zone is between about 180 to about 450° C.
13. The apparatus of claim 1 , further comprising a condenser connected to the reaction product output of the reactor and comprising a condensed reaction product output.
14. The apparatus of claim 13 , further comprising a separator, or two or more successive separators, connected to the condensed reaction product output of the condenser and comprising a gas output, a liquid water output, and a liquid reaction products output.
15. The apparatus of claim 1 , wherein the partial oxidation metal catalyst is an unsupported or supported transition metal of the groups IIIB to VIIIB.
16. The apparatus of claim 1 , wherein the Fischer-Tropsch catalyst is unsupported or supported Fe, Co, Ni, Pd, Pt, Rh, and Ru, in metal form or in oxide form.
17. A method for producing chemicals from a methane-containing gas in the apparatus of claim 1 , the method comprising the steps of:
(a) introducing a mixture of the methane-containing gas and air in the reactor comprising the partial oxidation reaction zone and the Fischer-Tropsch reaction zone,
(b) allowing the mixture to pass through the partial oxidation reaction zone at a temperature of about 800 to 1200° C., the partial oxidation reaction zone comprising the supported or unsupported partial oxidation metal catalyst, thereby producing synthesis gas,
(c) allowing the synthesis gas to pass through the Fischer-Tropsch reaction zone comprising the Fischer-Tropsch catalyst maintained at an appropriate temperature for Fischer-Tropsch reaction, thereby producing the chemicals, and
(d) collecting the chemicals from the reaction product output of the reactor.
18. The method of claim 17 , further comprising, before step (b), heating the partial oxidation reaction zone by burning methane in the partial oxidation reaction zone.
19. The method of claim 17 , further comprising, during step (b) maintaining the temperature in the partial oxidation reaction zone at about 800 to 1200° C. by varying a partial pressure of the methane-containing gas introduced in the reactor.
20. The method of claim 17 , further comprising condensing the chemicals and separating the condensed chemicals from water and remaining gaseous compounds.