Denitrification Rate

Screen denitrification capacity against kinetic volume, biodegradable carbon and nitrate load with caller rates; does not infer carbon bioavailability or recommend dosing.

Description

Denitrification removal can be limited by incoming nitrogen, kinetic capacity and usable carbon.

Denitrification removal can be limited by incoming nitrogen, kinetic capacity and usable carbon. Keeping those constraints separate shows which supplied capacity governs.^[1]

Screen denitrification capacity against kinetic volume, biodegradable carbon and nitrate load with caller rates; does not infer carbon bioavailability or recommend dosing.

When to use Denitrification Rate

Use this tool to screen denitrification capacity against kinetic volume, biodegradable carbon and nitrate load with caller rates; does not infer carbon bioavailability or recommend dosing.

Prepare the cohort, water, feed or equipment measurements for one consistent operating period. Confirm nitrogen reporting bases, dry/wet masses, flow units and supplied design assumptions.

How to use Denitrification Rate and understand its results

Prepare the cohort, water, feed or equipment measurements for one consistent operating period. Confirm nitrogen reporting bases, dry/wet masses, flow units and supplied design assumptions.
Enter reactorVolumeM3, calibratedRemovalKgNPerM3Day, availableCarbonKgCodPerDay, carbonRequirementKgCodPerKgN, nitrateLoadKgNPerDay using the field table and calculation rules, then run the tool.
Read kineticCapacityKgNPerDay, carbonLimitedCapacityKgNPerDay, predictedRemovalKgNPerDay, unremovedLoadKgNPerDay. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
reactorVolumeM3	Reactor volume m3	number	Required
calibratedRemovalKgNPerM3Day	Calibrated removal kg n per m3 day	number	Required
availableCarbonKgCodPerDay	Available carbon kg cod per day	number	Required
carbonRequirementKgCodPerKgN	Carbon requirement kg cod per kg n	number	Required
nitrateLoadKgNPerDay	Nitrate load kg n per day	number	Required

Enter positive reactor volume and COD requirement, with nonnegative kinetic rate, available carbon COD and nitrogen load. Return the two capacities, predicted removed nitrogen and unremoved load in the declared daily mass units.

kineticCapacity=reactorVolume×rate; carbonCapacity=availableCOD/CODperN; removal=min(load,kineticCapacity,carbonCapacity)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
kineticCapacityKgNPerDay	Kinetic capacity kg n per day	number
carbonLimitedCapacityKgNPerDay	Carbon limited capacity kg n per day	number
predictedRemovalKgNPerDay	Predicted removal kg n per day	number
unremovedLoadKgNPerDay	Unremoved load kg n per day	number

json

{
  "input": {
    "reactorVolumeM3": 10,
    "calibratedRemovalKgNPerM3Day": 0.1,
    "availableCarbonKgCodPerDay": 2,
    "carbonRequirementKgCodPerKgN": 4,
    "nitrateLoadKgNPerDay": 2
  },
  "output": {
    "kineticCapacityKgNPerDay": 1,
    "carbonLimitedCapacityKgNPerDay": 0.5,
    "predictedRemovalKgNPerDay": 0.5,
    "unremovedLoadKgNPerDay": 1.5
  }
}

Limitations and assumptions

This assumes the supplied carbon is available and the kinetic rate applies to current conditions. It does not design dosing, predict intermediates or establish effluent compliance.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use RAS Water Balance: Solve steady RAS purge/makeup from nitrate production, nitrate-bearing makeup and solute-free evaporation; distinguishes internal circulation from boundary replacement and excludes denitrification. For a complementary task, use Nitrification Rate: Measure net TAN disappearance and active-area-normalized rate across parallel streams; negative net removal is preserved and TAN disappearance alone does not prove nitrification.

References

Denitrification Rate — tool.io

Similar or alternative tools

RAS Water Balance
Solve steady RAS purge/makeup from nitrate production, nitrate-bearing makeup and solute-free evaporation; distinguishes internal circulation from boundary replacement and excludes denitrification.
Nitrification Rate
Measure net TAN disappearance and active-area-normalized rate across parallel streams; negative net removal is preserved and TAN disappearance alone does not prove nitrification.