Description
Return inventory = aerationVolume*aerationSolids+clarifierVolume*clarifierSolids and solidsRetentionDays = inventory/(wastedMassPerDay+effluentMassPerDay).
Mass-based environmental quantities depend on their basis: gross versus tare-corrected mass, wet versus dry solids, or material versus void volume. A ratio or density conversion is meaningful only when those bases and units agree.
Return inventory = aerationVolume*aerationSolids+clarifierVolume*clarifierSolids and solidsRetentionDays = inventory/(wastedMassPerDay+effluentMassPerDay).
When to use this tool
Use Activated Sludge Solids Inventory Term when reconciling supplied environmental masses, solids fractions or material volumes.
How to use the tool and how it works
- Enter aerationVolume, aerationSolids, clarifierVolume, clarifierSolids, wastedMassPerDay, effluentMassPerDay. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read inventory, solidsRetentionDays. Use the output convention below.
Require nonnegative aerationVolume, aerationSolids, clarifierVolume, clarifierSolids, wastedMassPerDay and effluentMassPerDay, with positive total mass loss per day. Return inventory = aerationVolume*aerationSolids+clarifierVolume*clarifierSolids and solidsRetentionDays = inventory/(wastedMassPerDay+effluentMassPerDay).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| aerationVolume | Aeration Volume | Required. Finite number; minimum 0. |
| aerationSolids | Aeration-zone solids mass per volume. | Required. Finite number; minimum 0. |
| clarifierVolume | Clarifier Volume | Required. Finite number; minimum 0. |
| clarifierSolids | Clarifier solids mass per volume. | Required. Finite number; minimum 0. |
| wastedMassPerDay | Wasted Mass Per Day | Required. Finite number; minimum 0. |
| effluentMassPerDay | Effluent Mass Per Day | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| inventory | Inventory | Required. Finite number. |
| solidsRetentionDays | Solids Retention Days | Required. Finite number. |
{
"input": {
"aerationVolume": 100,
"aerationSolids": 3,
"clarifierVolume": 20,
"clarifierSolids": 5,
"wastedMassPerDay": 30,
"effluentMassPerDay": 10
},
"output": {
"inventory": 400,
"solidsRetentionDays": 10
}
}Limitations and assumptions
- Solids inputs are mass concentrations and volumes must use their denominator unit. This assumes representative inventories and loss rates; it does not solve biomass kinetics, growth, decay or a changing plant mass balance.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use measured density, method-specific moisture procedures and uncertainty analysis where simple homogeneous-material assumptions are insufficient.
References
Similar or alternative tools
- Sludge Dry Solids Share
Return share = dryMass/wetMass and waterMass = wetMass-dryMass.
- Sedimentation Weirloading Overflowlength Term Tool
Calculate sedimentation weirloading overflowlength term from explicit caller-supplied inputs.