Conditions for Oxidative Treatment of Ammonia and Trimethylamine by Sodium Hypochlorite

Abstract

In an attempt to deodorize malodor from sewage or night soil treatment plants, removal of the two malodorous components, ammonia and trimethylamine was tried by absorptive exidation with hypochlorites. In a packed tower (packed height: 60 cm), gas containing ammonia (2-10 ppm) and trimethylamine (1-5 ppm) was absorbed and oxidized with sodium hypochlorite solution, whereby the overall mass transfer coefficient was examined to determine the optimum treatment conditions. The following were proved to be optimum for a room temperature treatment; superficial gas velocity: 1.7 m/s, liquid/gas ratio: 2, pH of the absorptive solution: around 7, concentration of sodium hypochlorite: 1.5×10^-3 mol/l.
An actual plant test under these conditions showed that ammonia and trimethylamine in real exhaust gas from a night soil treatment plant could be removed almost completely.