Study On Partial Nitrosation In SBBR-Anammox In UASBB Combined Process Treatment Low C/N Ratio Wastewater

The nitrogen pollution of water bodies in our country becomes more and more serious,the traditional nitrification-denitrification nitrogen removal process were different degrees of the existence of large power consumption,complicated process and need extra addition of organic carbon source and alkalinity,sludge production is big,easy to cause secondary pollution,high cost of treatment and a series of defects.And for a large number of landfill leachate,sludge dewatering liquid and other low carbon and high ammonium-nitrogen wastewater is not up to the ideal processing effect.The anaerobic ammonium oxidation technology provides a simple and economic biological nitrogen removal pathway for this kind of wastewater,thus attracted widespread attention,has the extremely high research value and broad application prospects.For the existing problems and hot research topics in the research of anaerobic ammonium oxidation technology in recent years,under laboratory conditions,low carbon-nitrogen ratio high ammonium-nitrogen wastewater was uesd as object in this test,through a small pilot test,experimental study on partial nitrosation process matching to anaerobic ammonium oxidation and anaerobic ammonium oxidation process respectively.Based on these studies,study on the nitrogen removal performance of partial nitrosification-anaerobic ammonium oxidation combined process was conducted.This project aimed to provide a theoretical basis and practical techniques for enlarged experiment research of combined process,so as to promote its application in practical engineering.Experimental studies have shown that domestication and cultivation of nitrosation bacteria in the SBBR reactor.The nitrosation process was started up successfully under continuous aeration and intermittent aeration conditions respectively.Through the comparative analysis that,due to intermittent aeration used aeration and stop aeration alternately,was more advantageous to the growth and reproduction of nitrosation bacteria.Under the condition of intermittent aeration,by the way of increasing influent NH4+-N concentration,the stable running of nitrosation process under high ammonia nitrogen loads conditions was effectively achieved.The optimal process parameters of the nitrosation process was:temperature for around 28?,DO=1.0mg·L-1,the initial alkalinity of five times,aeration frequency for aeration 15min/stop aeration 15min,aeration volume between 0.3?0.4L·min-1,pH=7.5?8.0 and CODcr<150mg·L-1.Conducted at this condition,the NH4+-N removal rate NO2--N accumulation rate and CODcr removal rate were above 90%84%and 78%respectively.For the influent NH4+-N concentration of 250mg·L-1,the preferable working sequence for partial nitrosation process matching to anaerobic ammonium oxidation was inflow(instant)-aeration(135min)-sedimentation and drainage(160min)-standby(185min).Using UASBB reactor seeded with anaerobic digestion sludge,after 124 days of continuous running,the anaerobic ammonium oxidation process was started up successfully.During the stable running period,the removal rate of NH4+-N and NO2--N averages were 92.12%and 93.00%respectively,the ratio among the removal of NH4+-N and NO2--N and the of generated NO3--N was 1:(1.34±0.10):(0.30±0.05),the effluent pH was slightly higher than the influent.Through the reasonable control of the influent substrate concentration and HRT,effectively improve the nitrogen removal performance of anaerobic ammonia oxidation process,TN removal rate and TN volume load averages were 85.25%and 0.4634kg·m-3·d-1 respectively.The optimal process parameters of anaerobic ammonia oxidation process were:HRT=24h,NH4+-N/NO2--N ratio for 1.1?1.3,DO density for 0.1?0.5mg·L-1,temperature for around 30?,pH=8.0,inorganic carbon source concentration for 1.5-2.0g·L-1 and CODCr<150mg·L-1.By adding different kinds of organic matter in the system,the strongest inhibition to the activity of anaerobic ammonium oxidation:bacteria was phenol,the weakest was glucose;the strongest of denitrification was formic acid,the weakest was sodium acetate.Through continuously adding a certain concentration of organic matter to the influent(CODcr=150mg·L-1),in the system cooperative denitrification relations gradually formed butween denitrifying bacteria and anaerobic ammonium oxidation bacteria.Under preferable working condition with organic carbon,the average removal rale of NH4+-N NO2--N and TN reached 89.47%96.38%and 91.24%respectively,CODcr removal rate can be maintained at more than 85%.After a phrase of adjustment and adaptation,the treatment effect of various pollution factors in the simulation low carbon-nitrogen ratio high ammonium-nitrogen wastewater with SBBR partial nitrosification-UASBB anaerobic ammonium oxidation combined process were all good,and average removal rates of NH4+-N TN and CODcr reached to 91.80%84.84%and 86.82%separately.For the treatment of sluudge liquor,nitrogen removal effect of combined process is still relatively ideal,NH4+-N and removal rate can be stabilized at more than 70%,CODcr removal rate can be maintained at a high level,with an average of up to 76.42%,has achieved initial success.Partial nitrosification-anaCrobic ammonium oxidation combined process can solve the problem of large amount of organic carbon adding and its consequent problems of high running cost and secondary pollution(?)of the traditional biological denitrification process.The combined process can per(?)preferable nitrogen removal performance and and reduce processing costs in the treating of low carbon and high ammonium-nitrogen wastewater.So the economic benefit,social benefit and environmental benefit is great.