Set the flow, peak factor and water temperature — get the chamber volume and diameter from the
Stokes settling velocity of 0.2 mm sand, the detention time, and the daily grit production. The compact,
hydraulically-binned alternative to the horizontal grit channel in tropical headworks.
1Duty & chamber
Vortex grit bins the flow into a swirling column; heavy sand spirals to the centre hopper while
organics stay in suspension. Size by peak flow and the settling velocity of the design grain.
Results — chamber & grit
Chamber volume V
—m³
Diameter D
—m
Grit / day
—kg/d
Item
Value
Basis
2Settling check
Stokes settling of the design grain at temperature T — the vertical velocity the chamber must stay below to capture it.
Item
Value
Basis
Operation envelope
Item
Value
Basis
Quote the grit instruments at factory price
A vortex grit chamber still needs a magnetic flowmeter on the inlet and a level transmitter on the hopper —
both in our catalogue, supplied at the manufacturer's ex-works price with the margin coming only from the export tax rebate.
Response within 24 hours · Inputs stay in your browser — nothing is uploaded.
Sources & parameter basis
[1]
METCALF & EDDY 5th ed. / WEF MOP-8 — grit chamber peaking 1.5–3×, design grain 0.2 mm, grit production 5–10 L per 1000 m³ (0.005–0.010 m³/1000 m³), side-water depth 1.0–2.0 m.
[2]
Stokes law v = g(ρs−ρw)d² / (18 μ); ρs = 2650 kg/m³; μ from water viscosity at temperature T (μ≈0.798 mPa·s @ 30 °C, 1.002 @ 20 °C).
[3]
Grit bulk density ≈ 1600 kg/m³ (wet). Daily mass = volume × 1600.
Full derivation and worked example: Vortex-Grit-Calculation-Sheet.md. The vortex chamber is the hydraulically-binned alternative to the horizontal grit channel — run it, then carry Q into the primary clarifier.
