Application - Wastewater Chemistries - Nutrient Removal

Most Frequently Asked Questions  


Parameter Purpose of Test Method
BOD5 Provides a relative measure of "food" available, the degree of stabilization of the wastewater and to estimate the effect of the effluent on the receiving water body. Used for plant loading/design, discharge rate for industrial facilities, and EPA NPDES reporting. 5 day test is too long for process control — many plants use COD or TOC as early estimate. Used to calculate % removal. 8043
8215
8229
Nitrite, LR
Indicative of the stage of conversion of ammonia and organic nitrogen forms to nitrate by the aerobic biological treatment steps (nitrification). Nitrite is the intermediate nitrogen form between ammonia and nitrate. Nitrite is highly toxic, and small amounts can upset the delicate biology of a wastewater plant. 8507
10019
10207
Ammonia
Monitor conversion of ammonia and organic nitrogen forms to nitrite and nitrate during the WW treatment process. Provices information on process conditions in biological treatment stages. At high concentrations an pH, ammonia can be toxic to sludge digestion microbes. 8038
10031
10205
Phosphate, Reactive LR
Phosphorus effluent concentrations are often controlled by discharge permits, to limit addition of nutrients to the receiving body. Phosphate is removed via biological nutrient removal prcesses and/or chemical precipitation. Reactive (ortho) phosphate is the phosphorus form that is most available to biological species. Total Phosphate includes orth-, poly-, and organic forms. 8048
8178
10209
Nitrate, HR
Indicative of the stage of conversion of ammonia and organic nitrogen forms to nitrate by the aerobic biological treatment steps (nitrification). 8039
10020
10206
pH
Maintain proper (narrow) pH range for optimal biological processes — especially nitrification. Can indicate plant upsets by industrial discharges or development of anaerobic conditions within the plant. Important condition for methane formation and avoiding ammonia toxicity in sludge digesters. pH meter & electrode - see instrument manual
 
Alkalinity
Maintain buffering to mediate effects of acidic industrial discharges. Control nitrification conditions in secondary treatment processes. Maintain proper bacterial conditions in sludge digester. 8203
8221
Phosphate, Total LR
Phosphorus effluent concentrations are often controlled by discharge permits, to limit addition of nutrients to the receiving body. Phosphate is removed via biological nutrient removal prcesses and/or chemical precipitation. Reactive (ortho) phosphate is the phosphorus form that is most available to biological species. Total Phosphate includes orth-, poly-, and organic forms. 8190
10209
10210
Oxygen, Dissolved Measured to control aeration and save money. Also measures the amount of available oxygen for aquatic life in the effluent. DO is also commonly measured reportable parameter on NPDES permits. 8166
8215
8229
8316
8332
8333

Also Consider  

Parameter Purpose of Test Method
Nitrogen, Total Total of ammonia, nitrate, nitrite, and organic nitrogen forms. 10071
10072
10208
Nitrate, LR Indicative of the stage of conversion of ammonia and organic nitrogen forms to nitrate by the aerobic biological treatment steps (nitrification). 8192
Nitrite, HR Indicative of the stage of conversion of ammonia and organic nitrogen forms to nitrate by the aerobic biological treatment steps (nitrification). Nitrite is the intermediate nitrogen form between ammonia and nitrate. Nitrite is highly toxic, and small amounts can upset the delicate biology of a wastewater plant. 8153
10237
TKN
Total Kjeldahl Nitrogen
Total of organic and ammonia forms of nitrogen. 8075
Flow Measure standard in-pipe flow rate for NPDES permit requirements and to establish concentrations/total presence of key analytes.  
Solids Most commonly measured and regulated parameter on NPDES permits. Used to measure mixed liquor suspended solids concentration, return activated sludge/waste activated sludge concentration, influent suspended solids concentration, effluent suspended solids concentration, and % removal. 8006