Research On Operational Characteristics And Pollutants Removal Efficiency Of Jet Aeration Reactor

Jet Aeration Reactor (JAR), as a kind of typical effective biological treatment technology, has the advantages of, high volume load, shock load capability and stable treatment effect. This paper referred to the basic theory and research experience of high aerobic bioreactor both at home and abroad, designed a jet aeration reactor, investigated the performance of jet aeration device, studied the removal effects of COD and ammonia nitrogen in the high concentration organic wastewater and proposed the reactor’s operating parameters. The research lasts one year with the following conclusions:1. Jet Aerator has good performance of oxygen transfer, better than the conventional diffused aeration. Under certain conditions, increasing the length of the pipe can help improve the performance of the jet aeration device. In better conditions, the standard of the oxygen transfer coefficient of ejector KLas=0.390min-1, oxygen transfer capacity for qc=0.0322kg/h, oxygen transfer efficiency EA=22.55%>20%.2. Jet Aeration Reactor has good effect on the wastewater with high concentration of organic matter. When the COD concentration of the influent ranges from1350mg/L to7530mg/L, the COD removal rate is between70%and79%, while the average removal rate71%. The optimum of HRT is from4hours to6hours. The optimum pH value is determined in the range of6to8, and the maximum should not exceed9.3. Jet Aeration Reactor has high treatment efficiency of high concentration ammonia nitrogen wastewater. When NH4+-N concentration of the influent ranges form100mg/L-500mg/L, NH4+-N removal rate steady at79.4%to93.1%. When the HRT is6h, the ammonia nitrogen removal rate is highest. In conclusion, the better HRT of the system is6.0h. When pH is between8and9, the effluent concentration is further reduced and the best pH value ranges from8to9.4. Jet Aeration Reactor achieves good operating results in treatment of polyethylene glycol wastewater. The effluent COD removal efficiency remains above70%, with average removal rate74%. The reactor is stable with influent COD concentration from3540mg/L to6600mg/L. When the influent concentration of NH4+-N ranges from112.4mg/L to367.5mg/L, the NH4+-N removal rate is stabilized between80%and88%, the effluent NH4+-N is less than80mg/L and the average removal rate of NH4+-N is84%. With studying kinetics of jet aeration reactor treating PEG wastewater and the derivation of analysis, the constant of degradation of the substrate is obtained as following:K=6×10-5, vmax=0.213, Ks=855.1.