Integrated processes for anaerobically bioconverting hydrogen and carbon oxides to oxygenated organic compounds

A process for bioconverting CO, H2 and CO2 to oxygenated organic compound comprising:

• a. passing a gas feed comprising CO, H2 and CO2 into a primary reactor containing aqueous fermentation broth under aerobic fermentation conditions, said fermentation broth containing microorganisms adapted for bioconverting the gas feed to oxygenated organic compound, to produce oxygenated organic compound dissolved in the fermentation broth and an off gas;
• b. maintaining in said primary reactor a depth of fermentation broth of at least 10 meters;
• c. maintaining in said reactor a head space above the upper portion of the fermentation broth;
• d. continuously supplying the gas feed to said aqueous menstruum through an injector that uses a motive liquid to form a stable gas-in-liquid dispersion in the fermentation broth;
• e. bioconverting carbon monoxide and hydrogen and carbon dioxide to an oxygenated organic compound and providing off-gas from the aqueous menstruum in the head space;
• f. withdrawing from the head space of said reactor at least a portion of the off-gas;
• g. removing from the syngas reactor at least an aliquot portion of the fermentation broth containing oxygenated organic compound and containing biosolids;
• h. separating from said aliquot portion of the fermentation broth an aqueous biosolids-containing phase containing biosolids having a higher solids content and a reduced oxygenated organic compound concentration than said aliquot portion;
• i. recovering at least a portion of the oxygenated organic compound;
• j. recovering from the biosolids-containing phase an essential compound for the bioconversion of the gas feed to the oxygenated organic compound;
• and,
• k. returning the essential compound to the aqueous fermentation broth in the primary reactor.