The Treatment Of Bromoamine Acid Wastewater By The Combined ILAR-BAC Process

The purpose of this dissertation is to establish a new technology to treat bromoamine acid (BAA) wastewater. The combined Airlift Internal Loop Reactor(ILAR) and Biological Activated Carbon (BAC) was useful, the ILAR was used to pretreat BAA, the BAC was used to treat the BAA decolorization products.When using the ILAR to treat BAA wastewater with SBR, the Granular Activated Carbon (GAC) and sphingomonas xenophaga QYY were added directly. The results showed that the ILAR system could run steadily for over one month at the BAA concentration 650 mg/L. After one-month acclimation the decolorization rate of BAA was reached to about 90% within 13h, and the removal rate of COD was about 50%. The microorganisms fixed in GAC took the major role in the BAA decolorization, the suspended microorganisms were adhered with extracellular polymeric substances (EPS), so their precipitation performance were good. The system can run steadily under the following optimal conditions: GAC dosing ratio was 5%(v/v), the pH of influent water was not needed to be adjusted, the sedimentation time was 2 min, aeration rate was 0.72 L·min^-1, the reaction temperature was 25～30℃, the influent BAA concentration had not effect on the degradation. When the influent BAA concentration was above 200 mg·L^-1, the BAA decolorization products were easy to undergo auto-oxidation and the yellow intermediate products which were difficult to biodegrade were formed.During the BAA degradation process, the effluent COD value was high, the chroma was deep, decolorization products were easy to undergo auto-oxidation, so it was very important to using an exrea technology or method to treat the BAA decolorization.The results showed that the BAC process could inhibit the auto-oxidation of the decolorization products effectively, and BAA decolorization products could be biodegraded gradually. When there were no added sulphate, the concentrations of Br^- and SO₄^2- were increased as the COD concentration reduced. Ultimately, the release rates of Br^- and SO₄^2- were 72.2% and 66.9%, the COD removal efficiency was about 85.7%.The combined ILAR-BAC was used to realize high COD removal rate of BAA wastewater for the first time, according to it, the practical BAA wastewater could be treated effectly.