Effects Of Different Carbon Sources And C/N On Short-range Denitrification

Based on the impact of different FA on microbial nitrification process,the subject has got several conclusions below:?1?The influent COD concentration fluctuated between 90.3 230.3mg/L,The effluent COD concentration changed between5.4 ⁴9.8mg/L,average COD concentration of nitrifying end was 33.9mg/L,The COD removal rate changed between 50.2% ⁹4.1%,average COD removal rate was 71.1%;?2?Throughout the trial period,SBR systems have received a highly efficient and stable nitrogen removal.Influent NH4+-N concentration in 21.3 98.8mg / L range step change,effluent NH4 +-N concentration were lower than 2.8 mg/L,NH4 +-N removal rate of 98.6%;?3?FA in the system has a significant impact on AOR,NaPR.Through the operational period,FA by the 0.5mg/L increased to 10.17mg/L,AOR from the 2.88 mg/?L.h?gradutally to 26.49 mg/?L.h?.Instead,NaPR from 17.29 mg/?L.h?down to 0.53 mg/?L.h?.Also when the microorganisms have adapted to the conditions at a FA,The FA suddenly sharp rise,AOR and NaPR will produce a inhibition,but NaPR inhibition effect is more obvious;?4?FA has a certain impact on NRR in the system.With the increase of FA,the Ni RR gradually increases and the NaRR gradually smaller,finally down to 0;?5?When the FA was 10.17mg/L,the NiAR up to 97.1%.Using the FA inhibition,supplemented by the pH and DO real-time control policies,the SBR system obtained a stable shortcut nitrification-denitrification.The active sludge which are domesticated by four C/N conditions?noting for R0,R5,R10 and R15 respectively?are used as the research object,.The study employs artificial water distribution.Through the dosing of three different electronic acceptor?NO₂^--N?,we study the characteristics of the denitrification microbial which are domesticated by the different C/N conditions.The test results show that:?1?The denitrifying ability of R5 and R10 were best.After 15 min,the removal rate were 100% and the reduction rate were 0.67 mg/?L·min?.The denitrifying ability of R0 and R15 were weak.After 15 min,the removal rate were 88% and 41% and the reduction rate were 0.59 and 0.27mg/?L·min?.?2?In the whole test process,pH first continued substantially increasing,and speed up first and then slow.And when the denitrifying was end,pH would suddenly fall down to instruct the end of the test.In order to research the long-term and short-term impacts of nitrite nitrogen reduction process that used the real domestic wastewater as carbon source,we utilized the batche tests for SBR process in the basic of steadily acquiring biological denitrification capacity.This essay was discussed from two aspects: we investigated the influence of denitrification kinetics caused by carbon source from the real domestic wastewater for NO-2N electron acceptor lasting for 60 periods at the first stage.The consequence showed that the specific denitrification rate was 4.5 times as well as the beginning when we acclimated the activated sludge by adding carbon source from the real domestic waste water for 60 days.In the process,the rainfall make the content of COD lower in the real domestic wastewater,which prolonged the time of denitrification process and resulted in that the nitrite nitrogen could not be removed completely.We did the static batche tests in the second stage based on the first.And we investigated the effects of denitrification process respectively caused by the real domestic wastewater,sodium acetate,ethanol and carbinol.When we changed the carbon source,the adaptability of biological sludge became alterant.The outcome from this test exhibited that when we added carbon source into denitrification sludge and replaced the real domestic wastewater by sodium acetate,ethanol and carbinol,the specific denitrification rate of sodium acetate was speediest,and the real domestic wastewater's was faster than ethanol's.The specific denitrification rate of carbinol was the slowest one in the denitrification process.