Start up of deammonification process in one single SBR system.

Area of Science:

• Environmental Microbiology
• Wastewater Treatment Technologies
• Nitrogen Removal Processes

Background:

• Aerobic/anoxic deammonification is a recent autotrophic nitrogen removal process.
• This process involves partial ammonia oxidation to nitrite, followed by conversion to nitrogen gas.

Purpose of the Study:

• To acclimate deammonification in laboratory batch reactors using seed sludge from a landfill leachate plant.
• To compare deammonification performance with normal activated sludge.
• To investigate the influence of oxygen and intermediates (nitrite, hydrazine) on the process.

Main Methods:

• Utilized seed sludge from a landfill leachate plant's biological rotation disk.
• Acclimated deammonification in laboratory-scale batch reactors (Sequencing Batch Reactors - SBR).
• Conducted parallel tests with normal activated sludge.
• Investigated the effects of oxygen levels and chemical intermediates (nitrite, hydrazine).

Main Results:

• Deammonification activities were successfully obtained from seeded reactors.
• Limited deammonification performance was observed with normal activated sludge after several months of acclimation.
• Oxygen was identified as a critical factor influencing both acclimation and process operation.
• The study identified different limiting concentrations for deammonification bacteria compared to pure Anammox cultures.
• Hydrazine was tested for its potential to accelerate acclimation and recover activity from nitrite inhibition.

Conclusions:

• Deammonification can be established in laboratory settings using appropriate seed sludge.
• Process parameters like oxygen availability and intermediate concentrations significantly affect deammonification efficiency.
• Further research is needed to optimize deammonification processes and understand the role of intermediates.