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ABSTRACT: In order to study long-term effect of completely autotrophic nitrogen removal over nitrite (CANON) reactor, performance stability was investigated by using synthetic inorganic ammonia-rich wastewater as raw water with a continuous flow CANON reactor. Both performances of short-cut nitrification and ANAMMOX were stable for more than one year. Under the condition that inner temperature at 35 degrees C +/- 1 degrees C, pH 7.39 and 8.01, and hydraulic retention time 3.7-5.1 h, the average total nitrogen removal load was 1.8 kg x (m3 x d)(-1), and the average and maximum total nitrogen removal efficiency were 65.09% and 81.65% respectively. Under sudden low temperature conditions, both ANAMMOX bacteria and AOB were inhibited, however, the ANAMMOX bacteria were inhibited more, which caused highly accumulated nitrite. When temperature increased to 35 degrees C as normal, the performance of CANON reactor recovered soon, which means low temperature impact will have no significant influence on stability. When the temperature reached more than 50 degrees C, the activity of ANAMMOX bacteria was completely destroyed, so high temperature must be avoided, though AOB can recovered to normal in one week.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 10/2012; 33(10):3507-12.
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ABSTRACT: The start-up of CANON process was studied to reveal adaptability and how to condense time of start-up with a lab-scale experiment. During start-up stage, temperature was controlled at 35 degrees C +/- 1 degrees C, pH was 7.39-8.01 and free ammonium was 2.89-12.37 mg x L(-1). Partial nitritation was first built up in 60th day and kept steady, nitrite accumulation rate (NO2(-) -N/NO(x) (-) -N) was up to 98%. In the 160th day, the reactor started to show effects of anaerobic ammonium oxidation, and in the 210th day, CANON process was started-up under aerobic conditions successfully, and total nitrogen removal load was 1.22 kg/(m3 x d) and 70% removal rate on average was attained. When using ammonium wastewater without organic carbon sources as influent, there are two signs to indicate the CANON start-up: first, nitrogen gas was produced in carriers; the other one was the ratio of total nitrogen loss and increased nitrate keep steady, and in this study average ratio was 8.61 compared to theoretical value 8.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 07/2009; 30(6):1689-94.
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ABSTRACT: In the room temperature 14.7-24.7 degrees C, simultaneous nitrification-ANAMMOX (CANON) process for municipal sewage was tested by SBR while the DO was controlled between 0.05 and 0.30 mg/L. As a result, the research shows that CANON process can be applied to the nitrogen treatment of municipal wastewater in room temperature by SBR. DO can be regarded as the indication parameter of reaction terminal, and 1 mg/L has been confirmed in the experiment. In the exploring SBR experiments, the consumption velocity of NH4(+) -N was 0.164-0.218 kg/(m3 x d), the production velocity of NO3(-) -N was 0.026-0.036 kg/(m3 x d), the removal velocity and efficiency of TN were 0.124-0.194 kg/(m3 x d) and 65%-75% respectively. Additionally, in the improving SBR experiments, there were three methods for avoiding nitrite accumulation and increasing the nitrogen removal efficiency. They were improving temperature, adding non-aeration period of time and increasing the quantity of ANAMMOX bacteria. Therefore, the removal efficiency of TN was increased to 77%-88% through the three ways above. However, in view of the nitrogen removal velocity and the fact of engineering application condition, the third approach was the best to advance the general ability of ANAMMOX.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 07/2009; 30(7):2001-6.
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ABSTRACT: The test of anoxic phosphate uptake of denitrifying phosphorous removal bacteria (DPB) which was cultivated during the anaerobic/ anoxic/aerobic processes was conducted at the various situations of electron acceptors. The various concentrations of nitrate or nitrite were added during the anoxic stage respectively. The conclusions stated that the anoxic phosphate uptake of DPB was rarely influenced by the concentration of nitrate with the adequate nitrate as electron acceptors. It takes 1 mg PO4(3-) -P when the consumption of NO3(-) -N is 1 mg. The nitrite could be regarded as the electron acceptor to participate into the activities of denitrifying phosphorous removal. Compared with the nitrate, the phosphorous uptake rate of DPB with nitrite was rather higher at a low concentration (NO2(-) -N with the concentration range of 5 - 20 mg/L). Furthermore, the rate of anoxic phosphorous uptake was increased with the decreased concentration of NO2(-) -N. The restraining effects related to the anoxic phosphors uptake of DPB was increased as the increase of nitrite concentration. Hence, the anoxic phosphorous uptake of DPB was entirely inhibited when the concentration of NO2(-) -N was higher than 35 mg/L.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 08/2007; 28(7):1472-6.
