Clarifier Sizing
Size an ideal circular clarifier against caller hydraulic and solids loadings and report detention; settling performance, inlet hydraulics and short circuiting are external.
Description
Clarifier surface area must accommodate both hydraulic overflow and solids loading.
Clarifier surface area must accommodate both hydraulic overflow and solids loading. Circular geometry then relates that governing area to diameter and nominal detention time.1
Size an ideal circular clarifier against caller hydraulic and solids loadings and report detention; settling performance, inlet hydraulics and short circuiting are external.
When to use Clarifier Sizing
Use this tool to size an ideal circular clarifier against caller hydraulic and solids loadings and report detention; settling performance, inlet hydraulics and short circuiting are external.
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 Clarifier Sizing 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 flowM3PerHour, solidsLoadKgPerHour, maximumSurfaceOverflowMPerHour, maximumSolidsLoadingKgPerM2Hour, waterDepthM using the field table and calculation rules, then run the tool.
- Read hydraulicRequiredAreaM2, solidsRequiredAreaM2, governingAreaM2, circularDiameterM, nominalDetentionHours. 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 |
|---|---|---|---|
| flowM3PerHour | Flow m3 per hour | number | Required |
| solidsLoadKgPerHour | Solids load kg per hour | number | Required |
| maximumSurfaceOverflowMPerHour | Maximum surface overflow m per hour | number | Required |
| maximumSolidsLoadingKgPerM2Hour | Maximum solids loading kg per m2 hour | number | Required |
| waterDepthM | Water depth m | number | Required |
Enter positive flow, overflow rate, solids loading rate and depth with nonnegative solids load. The tool returns both area requirements, their maximum, equivalent circular diameter and detention hours.
area=max(flow/overflowRate,solidsLoad/solidsLoadingRate); diameter=2 sqrt(area/π); detention=area×depth/flow Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| hydraulicRequiredAreaM2 | Hydraulic required area m2 | number |
| solidsRequiredAreaM2 | Solids required area m2 | number |
| governingAreaM2 | Governing area m2 | number |
| circularDiameterM | Circular diameter m | number |
| nominalDetentionHours | Nominal detention hours | number |
{
"input": {
"flowM3PerHour": 100,
"solidsLoadKgPerHour": 50,
"maximumSurfaceOverflowMPerHour": 2,
"maximumSolidsLoadingKgPerM2Hour": 1,
"waterDepthM": 2
},
"output": {
"hydraulicRequiredAreaM2": 50,
"solidsRequiredAreaM2": 50,
"governingAreaM2": 50,
"circularDiameterM": 7.978845608028654,
"nominalDetentionHours": 1
}
}Limitations and assumptions
Allowable rates are supplied design assumptions. Settling distribution, short-circuiting, sludge removal and actual capture performance are not modeled.
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 Settling Velocity: Calculate signed ideal spherical-particle Stokes settling and check Re≤1; upward buoyancy is retained, and nonspherical, flocculated and hindered settling are not modeled. For a complementary task, use Drum Filter Sizing: Size effective drum-filter area from calibrated hydraulic/solids fluxes and available duty; backwashing, mesh capture and vendor ratings are supplied externally.
References
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Clarifier Sizing — tool.io
Similar or alternative tools
- Settling Velocity
Calculate signed ideal spherical-particle Stokes settling and check Re≤1; upward buoyancy is retained, and nonspherical, flocculated and hindered settling are not modeled.
- Drum Filter Sizing
Size effective drum-filter area from calibrated hydraulic/solids fluxes and available duty; backwashing, mesh capture and vendor ratings are supplied externally.