The ammonia oxidation is stopped at the nitrite
step by operating the SHARON® process at an
elevated temperature. At higher temperatures,
the ammonia oxidizers grow significantly faster
than the nitrite-oxidizing bacteria. In this
process the hydraulic retention time (HRT) is
equal to solids retention time (SRT). Therefore
the slow-growing nitrite oxidizers are washed
out of the system and the ammonia oxidization
is stopped at nitrite.