Spontaneous Initiation And Maintenance Of Partial Nitritation For Household Toilet Wastewater Treatment

Partial nitritation (PN) can be achieved in the aerobic treatment of toilet wastewater (TW) independent of accurate control of working parameters due to its high concentration in free ammonia and a low ratio of alkalinity to total ammonia nitrogen. Although the mechanism of spontaneously realizing the ideal PN for TW has been clearly elaborated, few researches on the application of PN to household toilet wastewater (HTW) treatment are available. In this study, a biofilm reactor was established to study the PN of HTW, especially focusing on the effect of HTW drainage characteristics on the PN. After a 100-d operation, the results showed that the ideal PN can also be initiated and maintained spontaneously for HTW. Moreover, the drainage characteristics of HTW is beneficial for maintaining the stability of PN and achieving sludge reduction, which will support the establishment of subsequent partial nitritation anaerobic ammonia oxidation process for HTW.