| 摘要 |
Disclosed is an apparatus for purifying acid mine drainage capable of discharging alkaline wastewater without the need to neutralize the alkaline wastewater by using a small amount of alkaline chemicals. The purifying apparatus comprises a reaction tank for oxidizing iron ions by supplying air or oxidant to acid mine drainage including iron ions, and being provided with an alkaline agent; a coagulation tank for forming flocs by providing polymers for the acid mine drainage having iron ions oxidized; a precipitation tank for generating sludge by precipitating the flocs, and discharging upper water to outside; and a concentration tank for concentrating the sludge and discharging upper water to outside. Part of the concentrated sludge is transferred to an oxidation tank. Accordingly the removal efficiency of iron ions can be improved, the total amount of generated sludge can be reduced, and the costs for a facility and chemicals to neutralize the discharged wastewater can be reduced by making the pH in the oxidation tank lower than ever and reusing the generated sludge as absorbent or catalyst. [Reference numerals] (40) Oxidation tank;(50) Reaction tank;(60) Coagulation tank;(70) Precipitation tank;(80) Concentration tank;(AA) Alkaline chemicals (NaCH or Ca(OH)2);(BB) Process water;(CC) AIR or Oxydizer;(DD) Supernatant;(EE) Enriched sludge;(FF) Sludge disposal |
