Biological sulfide prestripping for metal and COD removal

Abstract

Organic wastes of high concentration and containing high concentrations of metals have generally been treated by a preliminary metal removal process (for example, precipitation) followed by biological treatment of the degradable component of the organic matter. It was the objective of this study to determine if a high strength waste containing metals could be treated by a precipitation‐anaerobic digestion process in which the precipitant was sulfide generated by the digestion step itself. To answer these questions, laboratory reactors were fed a synthetic medium (containing copper as the metal of interest and glucose and acetate as primary organic substrates) and operated in a semicontinuous draw and fill manner. Overall, the results of this study are encouraging and point to the potential feasibility of the process.

Anaerobic processes

“…A metal precipitation-anaerobic digestion process was explored for the pretreatment of heavy metal-bearing wastewaters by use of the sulfide generated by the digestion step. Results indicated that the process is potentially feasible (Haas and Polprasert, 1993). Mergaert et a!'…”

Combined strategy for the precipitation of heavy metals and biodegradation of petroleum in industrial wastewaters

“…Biological sulfate reduction has been studied in various reactor designs, including the continuous stirred tank reactor (CSTR) [11], anaerobic contact process [12], anaerobic filter [13][14][15], up-flow anaerobic sludge blanket reactor (UASB) [5,10,16], hybrid reactor [6,17] and fluidized-bed reactor (FBR) [18].…”

Hazardous waste treatment technologies

“…Treatment efficiencies after 12 weeks varied from 66.8 to 92.6%. Haas and Polprasert ( 1993) studied the feasibility of using the sulfide generated from the anaerobic digestion process to treat high strength waste-containing metals. Overall results are encouraging regarding the potential use of this technique.…”