Recycling organic compounds from gasifier syngas condensate

1. A method for producing a synthetic gas, comprising:

gasifying a feedstock within a gasifier to produce a raw syngas;

processing the raw syngas within a processing device to produce a processed syngas;

separating the processed syngas into a vapor phase, an organic phase, and an aqueous phase within a separator;

introducing the organic phase to the gasifier;

introducing the aqueous phase to a stripper to provide steam and a condensate; and

introducing the steam into the gasifier.

2. The method of claim 1 , wherein the processed syngas comprises contaminants including at least one of benzene, toluene, xylene, naphthalenes, oxygen-substituted one and two-ring aromatics, phenol, phenanthracene, ethane, ethylene, and propane.

3. The method of claim 2 , wherein greater than about 40 mol % of the contaminants present in the processed syngas are recycled back to the gasifier via the organic phase and the steam.

4. The method of claim 1 , further comprising introducing a heat transfer medium to the stripper, wherein the heat transfer medium has a pressure between about 4,100 kPa and about 4,500 kPa.

5. The method of claim 1 , wherein the steam has a pressure between about 3,400 kPa and about 3,800 kPa.

6. The method of claim 5 , wherein a mixing zone in the gasifier where at least one of the organic phase and the steam is introduced has a pressure between about 3,400 kPa and about 3,800 kPa.

7. The method of claim 1 , further comprising:

vaporizing the organic phrase to provide a vaporized organic phase; and

introducing the vaporized organic phase to the gasifier.

8. The method of claim 1 , wherein processing the raw syngas further comprises:

removing particulates from the raw syngas with a particulate control device to provide a filtered syngas;

increasing a moisture content of the filtered syngas with a saturator to provide a saturated syngas; and

converting carbon monoxide in the saturated gas into carbon dioxide with a gas shift device to provide the processed syngas.

9. The method of claim 8 , further comprising introducing at least a portion of the condensate to the saturator.

10. A method for producing a synthetic gas, comprising;

gasifying a feedstock within a gasifier to produce a raw syngas;

processing the raw syngas within a processing device to produce a processed syngas, wherein the processed syngas comprises contaminants;

separating the processed syngas into a vapor phase, an organic phase, and an aqueous phase within a separator, wherein the organic phase and the aqueous phase each include at least a portion of the contaminants;

introducing the organic phase to the gasifier;

stripping at least a portion of the contaminants from the aqueous phase in the presence of a heat transfer medium within a stripper to provide a contaminant steam and a condensate, wherein the heat transfer medium has a pressure between about 3,900 kPa to about 4,800 kPa; and

introducing the contaminant steam to the gasifier.

11. The method of claim 10 , wherein the contaminants comprise at least one of benzene, toluene, xylene, naphthalenes, oxygen-substituted one and two-ring aromatics, phenol, phenanthracene, ethane, ethylene, and propane.

12. The method of claim 10 , wherein the processed syngas has a contaminant content between about 50 ppmv and about 4,000 ppmv.

13. The method of claim 10 , wherein the organic phase has a contaminant content between about 40 mol % and about 99 mol %.

14. The method of claim 10 , wherein the aqueous phase has a contaminant content between about 0.1 mol % and about 20 mol %.

15. The method of claim 10 , wherein the contaminant steam has a contaminant content between about 0.1 mol % and about 20 mol %.

16. The method of claim 10 , wherein the condensate has a contaminant content between about 0.1 mol % and about 10 mol %.

17. The method of claim 1 , wherein greater than about 40 mol % of the contaminants present in the processed syngas are recycled back to the gasifier via the organic phase and the contaminant steam.