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.

Description

Observed TAN disappearance across treatment can be expressed as a mass rate and active-area loading.

Observed TAN disappearance across treatment can be expressed as a mass rate and active-area loading. Negative disappearance is meaningful when outlet concentration exceeds inlet concentration.^[1]

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.

When to use Nitrification Rate

Use this tool to 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.

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 Nitrification 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 inletTanMgNPerLiter, outletTanMgNPerLiter, flowsM3PerDay, activeMediaAreaM2 using the field table and calculation rules, then run the tool.
Read observedRemovalKgNPerDay, observedArealRateGramsNPerM2Day. 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
inletTanMgNPerLiter	Inlet tan mg n per liter	list of number	Required
outletTanMgNPerLiter	Outlet tan mg n per liter	list of number	Required
flowsM3PerDay	Flows m3 per day	list of number	Required
activeMediaAreaM2	Active media area m2	number	Required

Enter positive active area and aligned nonempty nonnegative inlet TAN, outlet TAN and flow lists. The tool sums signed mass differences and converts the total to g N/m²/day. Results may be zero or negative without input failure.

Paired lists must be nonempty and have equal lengths.

removalKgNPerDay=Σ(inletMgNPerL−outletMgNPerL)×flowM3PerDay/1000; arealRate=1000 removal/area

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

Output field	Meaning	Value type
observedRemovalKgNPerDay	Observed removal kg n per day	number
observedArealRateGramsNPerM2Day	Observed areal rate grams n per m2 day	number

json

{
  "input": {
    "inletTanMgNPerLiter": [
      2,
      3
    ],
    "outletTanMgNPerLiter": [
      1,
      1
    ],
    "flowsM3PerDay": [
      100,
      50
    ],
    "activeMediaAreaM2": 1000
  },
  "output": {
    "observedRemovalKgNPerDay": 0.2,
    "observedArealRateGramsNPerM2Day": 0.2
  }
}

Limitations and assumptions

Concentration disappearance alone does not prove nitrification: sampling, storage and other sinks can contribute. Steady paired flow/concentration observations and a consistent nitrogen basis are assumed.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Biofilter Sizing: Size active nitrifying surface against combined TAN loads with supplied peak/rate/derating assumptions; no media rating, startup guarantee or fish safety certification. For a complementary task, use Denitrification Rate: Screen denitrification capacity against kinetic volume, biodegradable carbon and nitrate load with caller rates; does not infer carbon bioavailability or recommend dosing.

References

Nitrification Rate — tool.io

Similar or alternative tools

Biofilter Sizing
Size active nitrifying surface against combined TAN loads with supplied peak/rate/derating assumptions; no media rating, startup guarantee or fish safety certification.
Denitrification Rate
Screen denitrification capacity against kinetic volume, biodegradable carbon and nitrate load with caller rates; does not infer carbon bioavailability or recommend dosing.