INDUCTION OF NITRITE BUILDUP IN WATER BY SOME COMMON DISINFECTANTS

Nitrite build-up in gold-mine service water could be caused by the bio tic oxidation of ammonia in the presence of disinfectants such as chlo rine, chlorine dioxide or bromine. It has been demonstrated in bench-s cale tests on gold-mine service water that complete nitrification can be inhibited. It was shown in these tests that dosages of chlorine bet ween 3 and 13 mg/l, chlorine dioxide between 2 and 8 mg/l, bromine abo ve 8 mg/l and cyanide above 2 mg/l caused selective inhibition of the second stage of the microbiological nitrification process. The nitrify ing bacteria appear to be able to adapt to bromine. Nickel (II) did no t significantly affect the nitrification process.