The start-up and operation performances of EGSB were investigated for municipal sewage treatment,and the key operational parameters were also analyzed.After 45 days,EGSB could be started-up effectively with the removal of CODCr and NH3-N being 58.8% and 32.9%,respectively.In the mean time,the removal efficiency of ammonia and nitrite were from negative to positive,and the anammox strengthened gradually.It was also found that the reactor operated well at ambient temperature with the average CODCr removal efficiencies of 66.6%.The average removal efficiencies of NH3-N,NO-2-N and NO-3-N were up to 90% and the anammox appeared markedly in this system.The quality of the effluent in the system could meet grade I of Integrated Wastewater Discharge Standard(GB 8978—1996).It was suggested that the HRT of EGSB in operation is less than 2 h and the reflux ratio less than 400%.

Two groups of different mixed sludges,with one group including anaerobic granular sludges,malodorous river sediments and aerobic activate sludge(R1),and the other including anaerobic digested sludge,malodorous river bottom sludge and aerobic activate sludge(R2),were used as inocula in two parallel ASBR systems treating actual municipal wastewater for 180~210 d.At the end of the experiment,the inner cultured sludge were observed by scanning electron microscope for analysis of their surface morphology.It was found that anaerobic ammonia oxidation(ANAMMOX) could be successfully achieved in the two systems.The ANAMMOX occurred after operation of 135 days.Additionally,removal efficiencies of NH+4-N(97.35%) and NO-2-N(99%) were observed at the stable stage in the R1 reactor.Comparatively,the R2 reactor took on notable ANAMMOX after 102 days' operation,the averaged removal efficiencies of ammonia and nitrite were 93.17% and 99% respecfively during stable operation.Taken together,the mixed sludge of R2 can be deemed as a relatively ideal inoculum for the ANAMMOX reactor due to its quicker start-up.The electron microscopy results showed that the anammox bacteria may exist in ASBR reactor.

Based on the microbial synergism,the current status of hybrid nitrogen-removal technology was reviewed mainly including simultaneous nitrification and denitrification,synergism of anaerobic ammonium oxidation and denitrification,simultaneous denitrification and methanogenesis,coupling of anaerobic ammonium oxidation,methanation and denitrification.The main principles,process and characteristics are also discussed.This paper may provide a useful reference for effective N-removal of wastewater.

Pontederia cordata was cultivated in 9 tanks with various planting densities(densities: 5,10,20)to investigate diurnal variation of physiological status of the plants including peroxidase(POD) and catalase(CAT) activities of the roots,soluble proteins(SP),chlorophyll(Chl) contents of the leaves and main physical and chemical traits of the effluents.Morphological dimensions,tillers,roots densities,biomass and nitrogen(N) and phosphorus(P) accumulation of the plants are measured.Correlation between diurnal variation of the physiological status of the plants and N and P removals of the effluents is analyzed,and effects of planting densities are researched.Results show POD and CAT activities of the roots,Chla,Chb and SP contents of the leaves have positive correlations with NH+4-N and soluble P removals of the effluents.In the tanks with higher planting densities,the plants are higher and bigger,and have more tillers,roots densities,biomass and N and P accumulation,higher Chla,Chb and SP contents of the leaves and NH+4-N and soluble P removals of the effluents,while POD and CAT activities of the roots declined.With stronger sunlight,POD and CAT activities of the roots,Chla,Chb and SP contents of the leaves,NH+4-N and soluble P removals of the effluents all increase.Chla,Chlb and SP contents of the leaves and the outlet DO show double-peak styles at about 12:00 pm and 14:00 pm.In 10:00 am～14:00 pm,CAT andPOD activities of the roots,Chla,Chlb and SP contents of the leaves,NH+4N and soluble P removals of the effluents all exceeded the other times at the day.

Three different mixed sludges,including anaerobic granular sludge and aerobic activate sludge,river sediments and aerobic activate sludge,anaerobic digested sludge and aerobic activate sludge,were used as inocula in three parallel SBR systems treating typical municipal wastewater,respectively.It was found that the anaerobic ammonia oxidation(ANAMMOX)reactors could be successfully started-up after 150～180 days' operation with the NH_4~+-N removal efficiencies of 88%,80%and 85%,respectively.Moreover,all the NO_2~--N removal efficiencies of these reactors were more than 96%.Comparatively,the start-up period of the seeding sludges, namely the mixed anaerobic digested sludge and aerobic activate sludge,was relatively the shortest.Therefore,the above mixed sludge can be considered a promising inoculum for the start-up of AMAMMOX reactor.

By adding ammonium into the raw wastewater to simulate the low C/N shock,two sets of lab-scale A2/O (anaerobic-anoxic-oxic) system were constructed to investigate the physiological biochemical activities of the shock and further restoration.Results showed that oxygen uptake rate (OUR), dehydrogenases activity (DHA), adenosine triphosphate (ATP) and poly-β-hydroxybutyric acid (PHB) responsed well to the shock with a drop over 81.8%、87.0%、90.5% and 72.9%,respectively.Both increasing the sludge reflux ratio (R) and reducing the sludge retention time (SRT) were effective restoration measures.After the restoration the value of R,OUR barely resumed, however, DHA、ATP and PHB still had a 10% to 20% gap left,compared to those before the shock.The reduction of SRT could gradually eliminate impacts of the shock by discharging the damaged sludge.Although the A2/O system didn’t well perform during the restoration period,all of the four physiological and biochemical activities of micro-organisms recovered fully in the end.

The mode of lowering DO in the aerobic tank was used to accumulate NO-2-N for enhancing ANAMMOX reaction in the anoxic tank,thus improving the nitrogen removal efficiency of A2/O process.The results show that the concentration of NO-2-N is increased by 500% when DO concentration is 0.5 to 1.0 mg/L in the aerobic tank.The effective accumulation of NO-2-N is formed,and ANAMMOX reaction is enhanced.The removal rates of NH+4-N and TN in the anoxic tank are improved by 15% and 9% respectively.The removal rate of TN in the whole system is improved by 7%.It is known through the software analysis of SPSS13.0 that the nitrogen removal efficiency of A2/O process with ANAMMOX enhancement reaction is remarkable.However,lowering DO has negative influence on the removal of COD and TP,and the removal rates of COD and TP are decreased by 5% and 1.4% respectively.

采用人工配制的低C／N废水对常规AVO系统和强化ANAMMOX系统进行冲击试验，确定其冲击耐受极限，并比较采用ANAMMOX技术的优劣。结果表明，低C／N废水对A^2／O系统的脱氮功能有明显的抑制作用，C／N=3．5可有效降低系统的硝化功能，C／N=1．2可使反硝化功能完全停止；而采用ANAMMOX反应的A^2／O系统对低C／N废水冲击下的脱氮能力有一定的提高，同比条件下，NH4^＋ -N去除率提高约9％，TN去除率提高约5％；但ANAMMOX反应对系统反硝化功能、COD和TP去除功能的作用不明显，同比条件下，两套系统的去除率差异不显著。

The original water of Bailonggang wastewater treatment plant was used to construct A2/O process,The influence of F/M on nitrogen removal was studied by regulating the BOD5 loading (F/M) of A2/O process. The results showed that the best range of F/M for COD remove was 0.15～0.28 gBOD5·gMLSS-1·d-1; the best range of F/M for BOD5 remove was 0.14～0.22 gBOD5·gMLSS-1·d-1;the best range of F/M for denitrification was 0.13～ 0.23 gBOD5·gMLSS-1·d-1. the best range of F/M for nitrification was 0.14～0.28 gBOD5·gMLSS-1·d-1. According the analyse,the best range of F/M for the A2/O system was 0.14～0.22 gBOD5·gMLSS-1·d-1.

The coal slurry method is based on aqueous catalyzed oxidation principle in the process of flue gas desulfurization.Analyzing of the changes of iron concentration and pH in coal slurry after the reaction of SO2 in the flue gas and pyrite in the coal, the experiment focused on the infection regularity of the amount of the pyrite extraction in the impact of slurry amount and the size of coal.The experimental results show that the density of iron ion in the coal slurry upper liquid increased with the reaction;the appearing rate of the pyrite has disparity too when response condition is the same but the absorbent amount is different;the iron precipitation rate is rela-tively faster about 60 minutes later.Therefore, the method could be used in the removal of sulfur dioxide in the flue gas of coal combustion, meanwhile it can be used to reduce the sulfur content of pyrite.With the desulfurization process, the pH has been gradually declining, particularly being declined faster in the first 30 minutes and then dropped a little range.