Study Phenol Wastewater Treatment Using The A/O Process

For the high ammonia nitrogen wastewater with phenol produced by coking industry and coal gasification industry,this study establishs a set of laboratory-scale processing apparatus based on A/O wastewater treatment process to study the process behavior of phenol and what impaction phenol has on the nitrification and denitrification process.At the same time,this study will verify the feasibility that phenol is used as a carbon source in denitrification and Simultaneous Nitrification Denitrification.Under anaerobic conditions,after 74 days of acclimatization,the removal rates of nitrate and phenol both above 99%were achieved with influent concentration of 160 and 520 mg·L-1 for nitrate and phenol respectively,the optimum C/N ratio was found to be 4.25 under the same nitrate load and the maximum specific denitrification rate 1.99 mgNo3--N·gVSS-1·h-1.Besides,the denitrification performace decreased obviously and became unstable when phenol was used as carbon source only,so readily biodegradable organics such as glucose was needed to improve the performace of the system.Under aerobic conditions,after 74 days of acclimatization,the removal rates of nitrate and phenol both above 99.9%were achieved with influent concentration of 120 and 960 mg·L-1 for ammonia and phenol respectively.When the C/N ratio was 5,the maximum rate of carbon oxidation was 224.1 mgCOD-gVSS-1 h-1,the maximum rate of denitrification was 0.87 mgNO3--N·gVSS-1·h-1;When we set the C/N ratio to 8,the maximum carbon oxidation rate of sludge was 197.7 mgCOD gVSS-1·h-1,the maximum denitrification rate was 1.63 mgNO3--N·gVSS-1·h-1.When the C/N ration increase in the influent,the denitrifying bacteria would become more activate but the carbon-oxidizing bacteria become less activate;there has been significant Simultaneous Nitrification Denitrification phenomenon in the aerobic system whose carbonsource is phenol.This study provide a simple,efficient and economic direction for the treatment of phenol,and provide the technical basis for the existing coking wastewater and coal gasification wastewater treatment,and provide technical reserves for the high ammonia biological wastewater with phenol treatment.