EFFECTS OF NITRILOTRIACETIC ACID-NICKEL COMPLEXES ON ACTIVATED-SLUDGEPROCESS

Effects of nitrilotriacetic acid (NTA), nickel ion (Ni2+) and their co mplexes on the efficiency of biological wastewater treatment, activate d sludge process, were evaluated by determining the changes in physica l and chemical parameters. Primary effects of these toxicants on micro organisms in the activated sludge process were evaluated by determinin g the change of in vivo dehydrogenase activity. The presence of 10 mg/ L or higher of Ni2+ significantly affected the activated sludge proces s. Nitrification in the activated sludge process was more sensitive to the inhibition of Ni2+. The presence of NTA, as high as 20 mg/L, didn 't significantly affect the activated sludge process. Moreover, in the presence of 20 mg/L of NTA, the toxicity of Ni2+ on the activated slu dge process was significantly reduced.