水中氨来源及处理
Source
Ammonia (NH3) gas, usually expressed as Nitrogen, is extremely
soluble in water. It is the natural product of decay of organic nitrogen
compounds. Ammonia finds its way to surface supplies from the runoff in
agricultural areas where it is applied as fertilizer. It can also find its way
to underground aquifers from animal feed lots. Ammonia is oxidized to nitrate by
bacterial action. A concentration of 0.1 to 1.0 ppm is typically found in most
surface water supplies, and is expressed as N. Ammonia is not usually found in
well water supplies because the bacteria in the soil converts it nitrates. The
concentration of Ammonia is not restricted by drinking water standards. Since
Ammonia is corrosive to copper alloys it is a concern in cooling systems and in
boiler feed.
Treatment
Ammonia can be destroyed chemically by chlorination. The initial reaction forms
chloramine, and must be completely broken down before there is a chlorine
residual. The chlorine will destroy organic contaminants in the waste stream
before it will react with the ammonia. Ammonia can also be removed by cation
exchange resin in the hydrogen form, which is the utilization of acid as a
regenerant. Degasification will also remove Ammonia.
