Simultaneous Nitrification and Denitrification Study in Sequencing Batch Reactor
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Explore the basics of Nitrification and Denitrification, the process of SND in SBR setting, experimental methods and results analysis for efficient nitrogen removal.
Simultaneous Nitrification and Denitrification Study in Sequencing Batch Reactor
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Presentation Transcript
Simultaneous Nitrification and Denitrification in a Sequencing Batch Reactor Will Lambert Robert Nwaokoro Stephen Russo
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • Results • Conclusions • Suggestions/Questions?
Nitrification/Denitrification Basics • Why remove nitrogen? • Limiting nutrient in oceans and estuaries. • Nitrates in drinking water cause Methemoglobinemia • “blue-baby” syndrome.
Nitrification/Denitrification Basics Organic Nitrogen Ammonia Fixation Ammonification Nitrification (aerobic) Nitrosomonas N2 (gas) Assimilation Denitrification (anaerobic) Nitrite Nitrification (aerobic) Nitrosobacters Denitrification (anaerobic) Nitrogen Cycle in Waste Treatment Nitrate
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • Results • Conclusions • Suggestions/Questions?
Introduction to SND • What is SND? • Simultaneous reactions occur of: • Ammonification • Nitrification • Denitrification • Normally occur in different steps • Why use SND? • Obstacles to SND • Solutions
Introduction to SND • What is SND? • Why use SND? • Reduction of: • Cost • Energy • Sludge • Obstacles to SND • Solutions
Introduction to SND • What is SND? • Why use SND? • Obstacles to SND • Nitrification is aerobic • Denitrification is anaerobic • Solutions
Introduction to SND • What is SND? • Why use SND? • Obstacles to SND • Solutions • Achieve aerobic/anaerobic environment: • Low DO • 0.5 – 1 mg/L • Large flocs • Biofilms
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • States • Testing Methods • Results • Conclusions • Suggestions/Questions?
Experimental Methods: States • Fill with Waste • Run for 18.3 s • 140 mL delivered • Based on 459 mL/min peristaltic pump flow rate • Fill with Water • Aerate • Settle • Drain
Experimental Methods: States • Fill with Waste • Fill with Water • Run for 350 s AND… • Reactor volume is 4 L over 5 s average • Fail safe if pump failed to deliver appropriate amount of fluid • Aerate • Settle • Drain
Experimental Methods: States • Fill with Waste • Fill with Water • Aerate • Run time varied • 8, 18, 24 hours • Aeration rate controlled by PID control • Target DO = 0.5 mg/L • Settle • Drain
Experimental Methods: States: Aerate • Proportional, Integral, and Derivative (PID) Control • Equation: • Trial and error determined P, I, and D values • Effective control was met when DO reached 0.5 mg/L
Experimental Methods: States • Fill with Waste • Fill with Water • Aerate • Settle • Run for 1 hour • More than enough time for settling • Left unchanged • Drain
Experimental Methods: States • Fill with Waste • Fill with Water • Aerate • Settle • Drain • Run until 1.2 L remained in reactor
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • States • Testing Methods • Results • Conclusions • Suggestions/Questions?
Experimental Methods: Testing Methods • Micro-Phenate Method • Determine ammonia concentration as ammonia/nitrogen • Standards consist of: • Phenol Solution • Sodium nitroprusside • Alkaline citrate • Sodium hypochlorite • Oxidizing Solution • Standards: 0, 0.2, 0.4, 0.6 mg N-NH4/L • Spectrophotometer analysis at 640 nm • Nitrate-nitrogen standards • Sampling
Experimental Methods: Testing Methods • Micro-Phenate Method • Nitrate-nitrogen standards • Cadmium gravimetric method • Hach Corporation: Nitriver ® and Nitraver ® reagent packets • Standards: 0, 2, 6, 10 mg N-NO3/L • Spectrophotometer analysis at 542nm • Sampling
Experimental Methods: Testing Methods • Micro-Phenate Method • Nitrate-nitrogen standards • Sampling • End of aeration state • Filtered through Millipore filter • Refrigerated • Ammonia samples • Diluted by 10x
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • Results • Conclusions • Suggestions/Questions?
Results: PID Average DO = 0.505 mg/L Standard Deviation = 0.015
Results: Samples Nitrate Concentrations Ammonia Concentrations
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • Results • Conclusions • Suggestions/Questions?
Conclusions • Total nitrogen removal efficiencies appeared to make sense • Broken down to nitrate and ammonia, unclear data • One long aeration cycle should have been run • Sampled periodically during that cycle • SND is possible at laboratory scale, • Easier at full scale • Achieve a more heterogeneous environment
SND in SBR • Nitrification/Denitrification Basics • Introduction to SND • Experimental Methods • Results • Conclusions • Suggestions/Questions?
Suggestions & Questions?