Question

What is total nitrogen?

Answer 1

Total nitrogen (`"TN"`) is the sum of ammonia nitrogen (`"NH"_3"-N"`), nitrate
nitrogen (`"NO"_3"-N"`), nitrite nitrogen (`"NO"_2"-N"`), and organically bonded nitrogen.

Explanation:

All measurements are expressed as the concentration of `"N"` in the sample.

`"NH"_3"-N"` is a constituent of raw domestic wastewater.

Various biological processes oxidize the `"NH"_3` to `"NO"_2^"-"` and `"NO"_3^"-"`.

Typical concentrations in wastewater are `"TN = 30 mg/L"` and `"NH"_3"-N = 15 mg/L"`.

The numbers vary with the jurisdiction, but a common limit for `"NH"_3"-N"` in the effluent after treatment is 1.25 mg/L.