Efficacy And Mechanism Of Simultaneously Combined Ozonation And Biodegradation Technology For Typical Industrial Wastewater Treatment

Intimately coupling technology of advanced oxidation and biodegradation were traditionally assembled by photocatalysts and biofilms,however,suffers from high energy consumption,poor light penetration to industrial wastewater,and potentially exerts secondary pollution due to catalyst loss.In this study,technology of simultaneous combination of ozonation and biodegradation?SCOB?is proposed,which replaces photocatalysis with ozone oxidation.It is a new type of intimately coupling technology with high efficiency,low consumption,and easy application.The main challenge for SCOB-construction is whether ozone will have a stress effect on biofilms,and optimizing the ozone dose is the entry point and key scientific issue for successfully establishing a SCOB system.The thesis takes simulated tetracycline hydrochloride wastewater?TCH?and actual biologically treated coking wastewater?BTCW?as research objects.By comparing results of the biodegradation alone?B?,the ozonation alone?O₃?and the SCOB using different ozone doses in the pollutant removal,toxicity reduction,operation stability and microbial survival status in systems of to determine the optimal ozone dose of SCOB,and analyze the synergy mechanism of ozonation and biodegradation during the operation of this system.SCOB can significantly improve the degradation of TCH and BTCW and reduce the toxicity of them.The optimal ozone dose for SCOB to degrade TCH is 2.0 mg-O₃/?L·h?.97%of TCH was removed within 2 h under SCOB.And the degradation rate constant was 29%higher than ozone alone.Moreover,the biomass remained stable,and the cell structure was relatively intact.The optimal ozone dose for SCOB to degrade BTCW is 80 mg-O₃/?L·h?.Compared with the O₃ system,the COD removal rate increased from 25%to 34%,the removal rate constant increased by 76%,and the total phenol degradation rate increased by 2%,the luminescence inhibition rate of 8h-effluent for Vibrio qinghaiensis sp.Q67?Q67?reduced by 70%,and the biomass loss was small at this dose,and the microbial cell structure was relatively complete.Excessive ozone dose will not significantly improve the removal of pollutants,and lower ozone doses will cause organisms to be poisoned by pollutants and cause unstable operation.2.0 mg-O₃/?L·h?and 80 mg-O₃/?L·h?are the optimal ozone doses for TCH and BTCW degradation with SCOB,respectively.Microorganisms can maintain high activity with these conditions,and cooperate with ozonation to promote pollutant degradation and toxicity reduction.This study lays an important theoretical foundation for the expansion and system amplification of intimately coupling technology of advanced oxidation and biodegradation.