Research On Storage And Reactivation Of Anaerobic Ammonium Oxidation Sludge

Nitrogen removal by conventional nitrification–denitrification processes requires large amounts of oxygen,carbon source,and energy.With the discovery of anaerobic ammonium oxidation(anammox),an alternative metabolic pathway was revealed.It is considered one of the most promising denitrification processes.However,due to the reduced biomass build-up of anammox bacteria,the start-up of treatment reactors is sometimes impeded: doubling times of between 7 and 29 days have been reported,and the successful build-up of an anammox reactor system usually required several months.To overcome this economic drawback,treatment reactors was often inoculated with efficient anammox biomass to shorten the start-up phase.Therefore,the rapid recovery of the storage method and the activity of Anammox was extremely important for the Anammox process engineering application.Under the room temperature(14 ~ 30?),outdoor frozen(Harbin winter outdoor environment(-25 ~ 0?)and frozen(-25?)conditions,respectively,this study investigated the effect of stored after different time and temperature through the determination of anammox sludge SAA decline value,and anammox activity decline trend.Then the effect of different storage temperature on the activity of anaerobic ammonia sludge was studied to optimize the temperature storage condition.Also exploring the rapid recovery of stored sludge,In this study,the structure and biomass changed of anammox sludge were studied by different storage time and storage temperature.This research was expected to provide useful information on the application of the granule-based anammox process in biological wastewater treatment and the further commercial production of anammox sludge.The experimental results show that the different storage time and storage temperature have different effects on the activity of anammox sludge.At room temperature,the specific anammox activities(SAAs)of the stored anammox sludge were 90.9%,64.3%,61.7%,43.2%,25.8%,19.3%,15.1% and 12.0% of the initial activity(activity before sludge storage)after 15,30,45,60,75,100,130 and 180 days,respectively.So the residual SAA decreased linearly with the increase of storage duration of anammox sludge(R2 was 0.951).At outside freezing conditions,the SAAs of the stored anammox sludge were 3.2%,4.8%,2.2%,-53.3% and-58.7% of the initial activity(activity before sludge storage)after 15,30,45,75 and 100 days,respectively.After 15 d storage,the activity of anammox sludge was almost disappear.Under the condition of frozen,the SAAs of the stored anammox sludge were 25.9%,13.0%,6.7%,-2.6% and-5.7% of the initial activity(activity before sludge storage)after 15,30,45,75 and 100 days,respectively.After the storage of 45 d,the sludge activity has been quite low.From 75 to 100 d,the sludge SAA was negative.At room temperature,the activity of anaerobic ammonia sludge was the slowest.The SAA decline was more evident than the frozen storage of the sludge in the outdoor freeze,The effect of temperature fluctuation on AnAOB in freezing process was significant.The SAAs after reactivation with storage duration of 15,30,45,60,75 and 130 days were all higher than the initial SAA.But the SAA after reactivation after stored 100 and 180 days was just 98.9% and 82.7% of the initial SAA.Frozen and outdoor freezing conditions,the sludge stores 100 d and the restored SAA is almost zero,which is much lower than the original SAA.As a result,the storage method for the storage and rapid recovery of anammox sludge was beneficial to the storage method of the non-exogenous matrix.At room temperature,the number of AnAOB was minimized,After storage of 100 d,the AnAOB was 84.03% before storage,and the AnAOB was 57.07% before storage after storing 180 d.Next,the AnAOB was 63.24% before storage,After storage of 100 d,under the condition of frozen.The largest change in AnAOB was outdoor freezing,just 2.3% before storage.Quantitative results by real-time quantitative PCR(qPCR)for the analysis of the sludge activity and the recovery process of denitrification effect and the change of proportion relationship provides the theory basis of molecular biology.also lay the foundation for the research and engineering application of the storage of anammox sludge.