▸ processconvert
Flotation

Flotation Cell Capacity Calculator

Flotation cell capacity is the volumetric sizing of a flotation or conditioning bank: how much total cell volume — and therefore how many cells — are needed to hold the slurry for a target residence time. From the slurry flow rate, a target residence time you supply (from testwork or the literature), and the working volume of one cell, this calculator returns the required total flotation volume, the number of cells (rounded up to a whole cell), the installed working volume, and the actual mean residence time the installed bank delivers. It is a preliminary, formula-based, educational sizing on inputs you supply. It is NOT a flotation recovery or grade predictor, NOT a flotation-kinetics model (rate constant, R∞), NOT a residence-time-distribution model, and NOT a cell mechanical/aeration/froth design or equipment-selection tool. The residence time is an input from testwork or the literature, never a predicted value. Final flotation design requires testwork, vendor data, operating data, and qualified review.

TypeInteractive engineering calculator

Calculator

m³/h

volumetric flow of slurry through the bank

min

from testwork or the literature — a value you supply

m³

effective working volume of a single cell

Result
Cells required4
Required total flotation volume66.6667 m³
Installed working volume80 m³
Actual residence time24 min
  • !Preliminary volumetric-capacity sizing only — this sizes the total flotation/conditioning volume, number of cells, and mean residence time from the slurry flow and a residence time YOU supply (from testwork or the literature).
  • !It does NOT predict flotation recovery or grade, model flotation kinetics or the residence-time distribution, design the cell (impeller, air rate, froth), or select equipment. Final flotation design requires testwork, vendor data, and qualified review.

Preliminary, formula-based flotation/conditioning volumetric-capacity sizing from a slurry flow and a user-supplied target residence time. Not a flotation recovery/grade predictor, a kinetics or residence-time-distribution model, a cell/aeration design tool, an equipment-selection tool, or a plant-optimisation tool. Final flotation design requires testwork, vendor data, operating data, and qualified review.

Related: Flotation Cell Capacity Explained · Pulp / Slurry Volumetric Flow · Residence Time · Hydromet & Slurry Calculations

Formulas

Required total flotation volume
V_req = Q × τ_target / 60
Cells required (rounded up)
N = ⌈ V_req / V_cell ⌉
Installed working volume
V_installed = N × V_cell
Actual residence time
τ = V_installed / Q × 60

Diagram

Flotation cell capacity — required volume, number of cells, and residence time from a supplied targetslurry feed Qfroth (concentrate)N cells · V_cell eachtailsV_req = Q · τ / 60 · N = ⌈V_req / V_cell⌉actual τ = installed volume / Q · 60volumetric capacity sizing — not recovery, kinetics, or cell design

Worked example

A flotation duty has 200 m³/h of slurry and needs a 20-minute target residence time; each cell has a 20 m³ working volume. Find the required total volume, number of cells, installed volume, and actual residence time.

  1. 01Required total volume: V_req = 200 × 20 / 60 = 66.67 m³
  2. 02Cells required: N = ⌈66.67 / 20⌉ = ⌈3.33⌉ = 4 cells
  3. 03Installed working volume: 4 × 20 = 80 m³
  4. 04Actual residence time: τ = 80 / 200 × 60 = 24.0 min
Result

Required volume 66.67 m³, 4 cells, installed volume 80 m³, actual residence time 24.0 min — a preliminary volumetric-capacity sizing, not a recovery or cell-design result.

FAQ

How does this calculator size a flotation bank?
It multiplies the slurry flow by the target residence time to get the required total flotation volume (V_req = Q × τ / 60, with τ in minutes), divides by the working volume of one cell, and rounds up to a whole number of cells. The installed volume is that cell count times the cell volume, and the actual residence time is the installed volume divided by the flow. It sizes capacity only.
Where does the target residence time come from?
You supply it — from flotation testwork (kinetics testing), the literature, or a comparable operation. The calculator does not predict it. That is the key boundary: flotation residence time is a design input here, not a calculated performance result. Use a residence time appropriate to the duty (rougher, cleaner, scavenger, conditioner).
Why is the actual residence time longer than the target?
Because the number of cells is rounded up to a whole cell. In the example, 66.67 m³ is required but four 20 m³ cells give 80 m³ installed, so the slurry actually sees 24.0 minutes rather than the 20-minute target. Rounding up guarantees the bank meets or exceeds the required capacity.
Does this predict flotation recovery or grade?
No. It sizes volumetric capacity and mean residence time only. It does not predict recovery or grade, model flotation kinetics or the residence-time distribution, design the cell (impeller, air rate, froth), or select equipment. Those require testwork, kinetic modelling, vendor methods, and qualified review.
Does it apply a froth or aeration holdup factor?
No. This calculator uses the cell working (effective) volume you enter directly, with no separate froth/aeration holdup factor. If you want to allow for holdup, reduce the cell working volume you supply or apply the allowance yourself — and note that such an allowance is a user-supplied estimate, not a cell design.

Related conversions