What is the process of nitrification in an activated sludge plant?

Question

Wastewater Treatment

Answer 1

The activated sludge process in wastewater treatment plants is basically a way of altering the content of solid wastes, generally reducing the amount of biological material and turning harmful chemicals into beneficial ones. There are many different kinds of plants that work in slightly different ways, so we'll start from the beginning.

The simplest kind of activated sludge process is basically one huge pool filled with sewage (sludge) and microorganisms (the 'activated' part). The microorganisms do all the work, and operators of the plant largely just try to keep the right ones in the right balance, and then skim them off to add to the next batch of sludge that comes through. The microorganisms do a variety of things, including killing off e.coli bacteria in the samples and turning ammonia into nitrates (nitrification).

More elaborate plants do the same kind of thing, but instead of using just one vat with one environment, they have several stages where different cultures are used in different steps. Some of the cultures cannot survive in air, and some require extra oxygen (the nitrification process is one of the latter usually), so the different 'vats' have a lot of different physical specifications based on the limitations or needs of the cultures within. But ultimately, it's the same general kind of thing - using microorganisms to handle stuff rapidly rather than just releasing it into the environment.

Hope that helps! The link below is much longer, better cited, and has pictures too, if you want more information!