Study on the Removal of Ammonia by Immobilized Nitrobacteria Pellets
|School||Shanghai Jiaotong University|
|Keywords||Embedding nitrobacteria Biofilm Nitrification rates Nitrite nitrogen accumulation rate Corn fermentation wastewater|
In this paper, the characteristics of immobilized and denitrifying bacteria and biofilm to remove ammonia various domesticated stage, and domesticated after different factors affect its activity and nitrification characteristics. The immobilized and nitrobacteria culture in a fluidized bed, denitrifying bacteria within the biofilm reactor is attached in the form of a biofilm growth in soft filler. Final study the immobilized and nitrobacteria processing corn fermentation wastewater nitrification ability. Experiment for nitrifying bacteria domesticated, temperature and dissolved oxygen in the nitration of the two reactors, different storage conditions impact on the immobilized and nitrobacteria active recovery and immobilized and nitrobacteria process of corn fermentation wastewater few two fronts. The main experimental results are as follows: 1) to maintain the continuous water conditions, immobilized and denitrifying bacteria after 37 days of acclimation, particle activity rose from the initial 10 mgNH4-N / L · h to 23.4mgNH4-N / L · h. The nitrification rate of the nitrifying bacteria in the biofilm reactor is increased by the time of the start of 2.0mgNH4-N / L · h from the initial to the end time of 11. 8mgNH4--N / L · h. 2) particle activity data for the same period with the PCR amplification results showed that the acclimatization period, embedded inside the particle content of nitrifying bacteria entrapped nitrifying bacteria significantly increased inside the particles substantially increase biomass. 3) Dissolved Oxygen 4mg / L to 2mg / L transition process, nitrification ability of immobilized and nitrification bacteria within the biofilm reactor nitrifying bacteria are affected, fluidized bed nitrification capacity is far higher than fixed bed. Not decreased dissolved oxygen in the fluidized bed before the ammonia degradation load up 34.1mgNH4-N / L · h, and the fixed bed highest only 11.8mgNH4-N / L · h. Reducing dissolved oxygen in the fluidized bed the ammonia degradation of load 28.4mgNH4-N / L · h, fixed bed for 9.5mgNH4-N / L · h. In addition, low dissolved oxygen conditions under two reactor showed a certain degree of nitrite nitrogen accumulation. 4) The temperature from the high to low transition process, the two-reactor nitrification bacteria nitrification rate has decreased nitrite accumulation phenomenon alleviate. Nitrite accumulation prone to high temperatures. 5) immobilized and nitrobacteria placed higher activity when stored at 4 ℃ can be quickly restored to active particle activity from 7 days out of the store after 1. 8mgNH4-N / L · h increased to 13.8mgNH4-N / L · h. 6) the immobilized and particle processing corn fermentation wastewater ammonia nitrogen, better removal efficiency, the system runs continuously stable effect. Wastewater does not exist in the substances to inhibit the activity of nitrifying bacteria. When the system influent ammonia concentration of 40mg / L, residence time of 2.5h ~ 3.5h, dissolved oxygen 4mg / L, the effluent ammonia concentration is basically up to 15mg / L or less, to meet emission standards. The presence of organic matter in the wastewater has little effect on nitrification.