The Biological Filtration Process Ammonia Emission Research

Ammonia was removed by a laboratory-scale biofilter. Compost was used as biofilter media and activated carbon as assistant material. The effects of empty bed retention time, gas introducing ways and influent ammonia concentration on the ammonia removal were studied. When the inlet ammonia concentration varies from 15.2 to 227.7 mg/rn3 (20 to 300 ppm), the ammonia removal efficiency was higher than 95% and the ammonia elimination capacity was from 0.0204 to 0.2344 g-NH3/kg- media/day. The experiment results showed that the optimum influent ammonia concentration should be under 151.8 mg/rn3 (200 ppm) for this biofflter in order to make the biofilter have good performance results and long life-span. The optimum gas introducing way was up-flow and the preferable retention time was 0.532 mm. The expenment results confirmed that ammonia was nitrified to nitrate in the biofilter and the biofilter bad stratification phenomenon in ammonia removal over the biofiltration depth which meant that the different parts of the biofilter had different weightiness in ammonia removal.