Nitrification And Denitrification Facilities Wastewater Treatment

Nitrification and Denitrification in the Activated Sludge Process, the first in a series on the microbiology of wastewater treatment, comprises the critical topics of cost-effective operation, permit compliance, process control, and troubleshooting in wastewater treatment plants. Avoiding the technical jargon, chemical equations, and kinetics that typically accompany such texts, Nitrification and Denitrification in the Activated Sludge Process directly addresses plant operators and technicians, providing necessary information for understanding the microbiology and biological conditions that occur in the treatment process. Of special interest to wastewater treatment plant operators are the bacteria that degrade nitrogenous wastes–the nitrifying bacteria–and the bacteria that degrade carbonaceous wastes–the cBOD-removing bacteria. Both groups of bacteria need to be routinely monitored and operational conditions favorably adjusted to ensure desired nitrification. Each chapter in this groundbreaking study offers a better understanding of the importance of nitrification and denitrification and the bacteria involved in these crucial processes. Chapters include: Organotrophs The Wastewater Nitrogen Cycle Nitrite Ion Accumulation Dissolved Oxygen Denitrifying Bacteria Gaseous End Products Free Molecular Oxygen The Occurrence of Denitrification

Nitrification and Denitrification in the Activated Sludge Process, the first in a series on the microbiology of wastewater treatment, comprises the critical topics of cost-effective operation, permit compliance, process control, and troubleshooting in wastewater treatment plants. Avoiding the technical jargon, chemical equations, and kinetics that typically accompany such texts, Nitrification and Denitrification in the Activated Sludge Process directly addresses plant operators and technicians, providing necessary information for understanding the microbiology and biological conditions that occur in the treatment process. Of special interest to wastewater treatment plant operators are the bacteria that degrade nitrogenous wastes–the nitrifying bacteria–and the bacteria that degrade carbonaceous wastes–the cBOD-removing bacteria. Both groups of bacteria need to be routinely monitored and operational conditions favorably adjusted to ensure desired nitrification. Each chapter in this groundbreaking study offers a better understanding of the importance of nitrification and denitrification and the bacteria involved in these crucial processes. Chapters include: Organotrophs The Wastewater Nitrogen Cycle Nitrite Ion Accumulation Dissolved Oxygen Denitrifying Bacteria Gaseous End Products Free Molecular Oxygen The Occurrence of Denitrification

Full-scale nitrification-denitritication of wastewater was conducted at the Newmarket, Ontario, Water Pollution Control Plant (WPCP), where primary stage lime treatment for phosphorus removal was being applied. The object of this study was to see what degree of nitrification-denitrification could be maintained within a system with lime treatment. Experiments involved denitrification mixed liquor thickening, methanol dosing and supplementary iron salt addition for phosphorus removal. Constant high (above 200 ml/g) sludge volume index (SVI) was experienced in both the nitrification and combined nitrification denitrification units at Newmarket. This was thought to be caused by lime addition to the primary stage. Full nitrogen conversion and removal were disrupted by sludge chlorination for SVI control. Sorne limitations of the conventional facility were also found to affect nitrogen removal. Supplemental addition of ferrous sulphate, late in the program, to the aeration basin improved phosphorus removal and decreased SVI. Subsequent pilot plant studies were carried out at Brampton and Kleinburg. In these a split-return mode of operation was evaluated under more controlled conditions. The requirements for methanol as a carbon source, process solids distribution, and post-aeration were evaluated for nitrification-denitrification under liquid temperatures ranging from 10 ta 25°C. Denitrification solids thickening and thus improved nitrate removal was observed. Post-aeration proved necessary to maintain low effluent suspended solids, but did contribute dissolved oxygen to the denitrification tank contents.