Sidestream RAS Fermentation for Stable Bio-P Combined with Short Cut Nitrogen Removal in an A/B Process

The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-time control of the biological process. Under appropriate ammonia loading rates, applicable ammonia valley and nitrate knee are detected. The real-time control of the SBMBR can be performed based on on-line ORP and pH measurements.

Download Full-text

Nitrogen Removal from Anaerobically-Treated Leachate

Water Quality Research Journal ◽

10.2166/wqrj.1984.008 ◽

1984 ◽

Vol 19 (1) ◽

pp. 87-100

Author(s):

D. Prasad ◽

J.G. Henry ◽

P. Elefsiniotis

Keyword(s):

Nitrogen Removal ◽

Air Flow ◽

Operating Conditions ◽

Air Flow Rate ◽

Flow Rates ◽

Anaerobic Filter ◽

Ph Values ◽

Wide Range ◽

Ammonia Desorption ◽

Effects Of Ph

Abstract Laboratory studies were conducted to demonstrate the effectiveness of diffused aeration for the removal of ammonia from the effluent of an anaerobic filter treating leachate. The effects of pH, temperature and air flow on the process were studied. The coefficient of desorption of ammonia, KD for the anaerobic filter effluent (TKN 75 mg/L with NH3-N 88%) was determined at pH values of 9, 10 and 11, temperatures of 10, 15, 20, 30 and 35°C, and air flow rates of 50, 120, and 190 cm3/sec/L. Results indicated that nitrogen removal from the effluent of anaerobic filters by ammonia desorption was feasible. Removals exceeding 90% were obtained with 8 hours aeration at pH of 10, a temperature of 20°C, and an air flow rate of 190 cm3/sec/L. Ammonia desorption coefficients, KD, determined at other temperatures and air flow rates can be used to predict ammonia removals under a wide range of operating conditions.

Download Full-text

Some Nitrogen Removal Aspects of a Contact Stabilization Plant

Water Quality Research Journal ◽

10.2166/wqrj.1968.008 ◽

1968 ◽

Vol 3 (1) ◽

pp. 127-154 ◽

Cited By ~ 1

Author(s):

P.H. Jones ◽

A.T. Downs

Keyword(s):

Nitrogen Removal

Download Full-text

Pre-Precipitation Facilitates Nitrogen Removal without Tank Expansion

Water Science & Technology ◽

10.2166/wst.1990.0233 ◽

1990 ◽

Vol 22 (7-8) ◽

pp. 85-92 ◽

Cited By ~ 2

Author(s):

Ingemar Karlsson ◽

Gunnar Smith

Keyword(s):

Waste Water ◽

Organic Matter ◽

Water Treatment ◽

Carbon Source ◽

Nitrogen Removal ◽

Waste Water Treatment ◽

Chemical Precipitation ◽

Sewage Water ◽

Laboratory Studies ◽

Denitrification Process

Chemically coagulated sewage water gives an effluent low in both suspended matter and organics. To use chemical precipitation as the first step in waste water treatment improves nitrification in the following biological stage. The precipitated sludge contains 75% of the organic matter in the sewage and can by hydrolysis be converted to readily degradable organic matter, which presents a valuable carbon source for the denitrification process. This paper will review experiences from full-scale applications as well as pilot-plant and laboratory studies.

Download Full-text

Nutrient Removal in Small Wastewater Treatment Plants

Water Science & Technology ◽

10.2166/wst.1990.0203 ◽

1990 ◽

Vol 22 (3-4) ◽

pp. 211-216

Author(s):

Niels Skov Olesen

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Wastewater Treatment Plants ◽

Ferrous Sulphate ◽

Practical Solution ◽

Sensitive Technique ◽

Pumping Station ◽

Denitrification Reactor

In some areas of Denmark nutrient removal is required even for very small wastewater plants, that is down to 500 pe (pe = person equivalents). The goal for the removal is 80% removal of nitrogen and 90% removal of phosphorus, or in terms of concentrations: 8 mg nitrogen/l and 1.2 mg phosphorus/l. The inlet concentrations are typically 40 mg N/l and 10 mg P/l. The paper presents the results from two such plants with a capacity of 800 pe. Phosphorus removal is made by simultaneous precipitation with ferrous sulphate. Nitrogen removal is carried out using the recirculation method. Both plants were originally rotor aerated oxidation ditches. They have been extended with a denitrification reactor and a recirculation pumping station. At present both plants have been in activity for about 3 years and with satisfactory results. Average concentrations of nitrogen (summer) and phosphorus is 7 mg/l and 0.9 mg/l respectively. Nitrogen removal seems to be a practical solution on these small plants. It is,though, sensitive to temperature and highly oxidized rain water. Phosphorus removal seems to be an easily run and relatively non-sensitive technique at least when using simultaneous precipitation.

Download Full-text