By Heather Jennings, PE

Today we are going to focus on nitrifiers, those wastewater treatment autotrophs that get energy from oxidizing ammonia. (Autotrophs are microorganisms that produce complex organic compounds using inorganic carbon from simple substances as a food source.) Oxidizing ammonia is a fancy way of saying ripping off hydrogens to stick oxygens onto nitrogen—the essence of nitrification.

In wastewater treatment we rely on bacteria to perform nitrification. While Nitrobacter and Nitrosomonas are the most commonly recognized, they are only part of a suite of autotrophic nitrifying bacteria that do the job. Mind you, there are also heterotrophic nitrifiers that are part of the floc-forming bacteria that help in the oxidation of ammonium, but we’re going to focus on the autotrophs this time around. [Read more…]