05076927 is referenced by 40 patents and cites 12 patents.

This invention comprises the steps of (1) acid phase anaerobic digestion of biomass to produce volatile acids and a stabilized sludge, (2) use of the volatile acids as the carbon source and electron donor for biological sulfate reduction for removal of acidity, metals and sulfate from acid mine drainage, and to produce acetate, (3) use of the acetate solution as feed for methane phase anaerobic digestion to produce methane and to reduce the organic content of the effluent of the process, (4) and use of the methane to satisfy the energy requirements of the process. Key to the process is the use of kinetic control (i.e., a relatively short mean cell residence time) to ensure partial oxidation of higher molecular weight volatile acids (e.g., propionic, butyric, valeric) and production of acetate during the sulfate reduction step. In this way, the higher molecular weight volatile acids produced during acid phase anaerobic digestion can be used both as electron donors for sulfate reduction (during which they are converted to acetate) and as substrates for the subsequent methane production step.

Biocatalyzed partial demineralization of acidic metal sulfate solutions
Application Number
Publication Number
Application Date
March 9, 1988
Publication Date
December 31, 1991
Robert M Hunter
320 S. Willson Ave., Bozeman, 59715
C02F 11/04
C02F 3/28
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