| The classical biotechnology has been widely applied in biological nitrogen removel process of wastewater. But the concept of continuable development has challenged the classical biotechnology of removel nitrogen which energy and motivity consume is very high. Therefore it is important that researching and delevoping new nitrogen removal biotechnology.In resent years,the new biotechnologies such as ANAMMOX,SHARON—ANAMMOX,CANON process have been the focus of research all around the world.Whereas the most new nitrogen removal processes have been limited in laboratory scale,it has been many problems in those processes when it was applied in practical wastewater.The problems include lower stability and the difficulty of controlling.This report adopted the new biotechnology of nitrogen removal based on the nitrosation technology to treatment the actual wastewater.The conculsion are as follows:1. It's possible on technological as well as economic that biological nitrogen removal treat the efflux of aerobic biological treatment of starch wastewater with Semi-Nitrosation—ANAMMOX process at normal temperature , and the process has excellent treatment ability of nitrogen . The average remavol rate of totle nitrogen achieved 80% in the integration process, and the maximum removal rate of total nitrogen was 85.5%. Volumetric total nitrogen load of inflow in airlift nitrosation bioreactor was 0.20kgN/m~3d.In ANAMMOX reactor, the volumetric total nitrogen load of inflow and the volumetric total nitrogen removal load were 1.11kgN/m~3d and 0.83kg/m~3d,and the maximum loads were 1.61kgN/m~3d and 1.29kgN/m~3d.2.It has been obtained sastisfactory result that biological nitrogen removal treat the sludge dewatering effluent with Semi-Nitrosation—ANAMMOX process at normal temperature.During the stable experiment,the average remavol rate of totle nitrogen was 79.15% in the whole process,and the maximum removal rate was 88.58%. In Semi-Nitrosation reactor, the volumetric total nitrogen load of inflow and the maximum load were 1.87 kgN/m~3d and 3.95kgN/m~3d ,it's minimum HRT was 0.094d.In ANAMMOX reactor , the volumetric total nitrogen load of inflow and the total nitrogen removal load were 0.88 kgN/m~3d and 0.59kgN/m~3d , the maximum load were 1.79 kgN/m~3d and 1.34kgN/m~3d ,it's minimum HRT was 0.094d.3.The influence of the impact of hydraulic load and the matrix concentration load to Semi-Nitrosation reactor were acceptable.In those conditions ,the maximum total nitrogen removal load of inflow in Semi-Nitrosation reactor achieved 6.06 kgN/m~3d and 7.44kgN/m~3d,and the drgree of nitrosation still were 42~50%.However the impact of matrix concentration load was obviously influented the ANAMMOX reactor.4.During the stable operating of the Semi-Nitrosation reactor, it has been found that the the phenomenon of autotrophic nitrogen removal significant generated, the average total nitrogen removal rate and the volumetric total nitrogen removal load were 40.05% and 0.65 kgN/m~3d,the maximum rate and load were 72.18% and 1.01 kgN/m~3d.At the same time, it has been found that the autotrophic nitrogen removal rate reduced as the total nitrogen load of inflow.However the performance of nitrosation increased as the total nitrogen load of inflow.The brown small granule sludge which spontaneous formatted in the Semi-Nitrosation reactor which consisted of the nitrosobacteria and the anammox bacterias as well as the red biomembrane which adhered to inwall of reactor contributed the autotrophic nitrogen removal.5.The single autotrophic nitrogen removal reactor (SANR) was successfully stated up with the protogenesis granule sludge.It has been obtain very well result that removal nitrogen of the sludge dewatering effluent with the SANR . when the total nitrogen concentration was 355.22mg/L and the average total nitrogen load of inflow was 0.91 kgN/m~3d,the maximum total nitrogen loads of inflow achieved 1.37 kgN/m~3d, the SANR's average total nitrogen removal rate was 74.81% and the maximum rate achieved 86.92%; the average total nitrogen removal load and the maximum load were 0.68 kgN/m~3d and 0.90 kgN/m~3d.The performance of SANR was been reinforced through add powder activated carbon.The total nitrogen removal rate and load were increased and the operation stability was improved, the maximum total nitrogen load of inflow and the removal load achieved 1.53 kgN/m~3d and 1.14 kgN/m~3d.6.The operation conditions of the Semi-Nitrosation reactor were the keys of the spontaneous formation of the granule sludge.It was in favor of the formation of granule sludge that small inorganic granule, the current shearing force and organic matter moderately existed.Longer SRT and lower DO were in favor of biological multiplicity in the granule sludge which helped to occurrence of autotrophic nitrogen removal.7. The observation results of optical microscope and SEM showed that, the nitrosation sludge was all the small granule sludge which structure was completed and which surface was smooth, and in those granules, many filamentous bacteric growed as the granules'frame, there were so many coccuse, ellipsoidal bacteric, bacillus and spiral bacteric on the granules. Howere the structure of anammox granule sludge was uncompleted, and the surface of the granule was coarseness.There were many bacillus and coccuse on the granules,and many filamentous bacteric existed in the granule.At the end of the experiment, many potozans appeared in the suspension sludge of the ANAMMOX which related to the long term lower nitrogen load.8.SRT and DO were the keys of the stability of nitrosation. According to the experiment, the operating conditions of stability of nitrosation were SRT≥100d, DO≤0.10mg/L,ALK of effluent= 200~300mg/L。The process control of semi-nitrosation could be realized in SBR which based on the variation of pH, ORP,dpH/dt and dORP/dt. 9.To achieve properer operation of biological nitrogen removal process, different process would be adopted according to the different concentrate of nitrogen.The new biotechnologies of nitrogen removal were more economical than traditional nitrification and denitrification and short nitrification and denitrification.
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