Hydrogen and methane production, energy recovery, and organic matter removal from effluents in a two-stage fermentative process.

This study evaluates the potential for using different effluents for simultaneous H(2) and CH(4) production in a two-stage batch fermentation process with mixed microflora. An appreciable amount of H(2) was produced from parboiled rice wastewater (23.9 mL g(-1) chemical oxygen demand [COD]) and vinasse (20.