Sulfidogenic fluidized bed treatment of real acid mine drainage water.
The treatment of real acid mine drainage water (pH 2.7-4.3) containing sulfate (1.5-3.34 g/L) and various metals was studied in an ethanol-fed sulfate-reducing fluidized bed reactor at 35°C. The robustness of the process was tested by increasing stepwise sulfate, ethanol and metal loading rates and decreasing feed pH and hydraulic retention time. Highest sulfate reduction rate (4.6g/L day) was obtained with feed sulfate concentration of 2.5 g/L, COD/sulfate ratio of 0.85 and HRT of 12 h. The corresponding sulfate and COD removal efficiencies were about 90% and 80%, respectively. The alkalinity produced in sulfidogenic ethanol oxidation neutralized the acidic mine water. Highest metal precipitation efficiencies were observed at HRT of 24 h, the percent metal removal being over 99.9% for Al (initial concentration 55 mg/L), Co (9.0 mg/L), Cu (49 mg/L), Fe (435 mg/L), Ni (3.8 mg/L), Pb (7.5 mg/L) and Zn (6.6 mg/L), and 94% for Mn (7.21 mg/L).
Sahinkaya
Erkan
E
Harran University, Environmental Engineering Department, Osmanbey Campus, 63000 Sanliurfa, Turkey. erkansahinkaya@yahoo.com
Gunes
Fatih M
FM
Ucar
Deniz
D
Kaksonen
Anna H
AH
D000143:Acids; D001419:Bacteria / Q000378:metabolism*; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D004583:Electrons; D000431:Ethanol / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000302:isolation & purification; D008906:Mining; D010084:Oxidation-Reduction; D012995:Solubility; D013431:Sulfates / Q000302:isolation & purification; D013440:Sulfides / Q000302:isolation & purification*; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
D000143:Acids; D019216:Metals, Heavy; D013431:Sulfates; D013440:Sulfides; D014874:Water Pollutants, Chemical; D000431:Ethanol