Reduction of Ammoniacal Nitrogen from Pigment Industry Effluent by Air Stripping

Removal of ammoniacal nitrogen from pigment industry effluent by the air stripping process was studied. Air stripping was subjected to two different samples having ammoniacal nitrogen concentration in the range of 15000- 16000 mg/L and 400-500 mg/L respectively. Air stripping was carried out using a lab scale aerator having a flow rate of 8 lpm. Effects of various operating parameters such as initial pH, stripping time and air flow on ammoniacal nitrogen removal were studied. pH optimizations had to be done as both the samples had different initial pH and ammonia/ammonium ratio shifts towards ammonia due to high pH. During the air striping, the stripping efficiency increased with increasing air flow and initial pH. The rate of decrease in concentration of ammoniacal nitrogen decreases with time.