Process reasoning
For a slurry volume flow Q in m³/h and bulk slurry density ρ in kg/m³, mass flow is Q × ρ. If dry-solids concentration x is a mass fraction, the dry-solids load is Q × ρ × x. Weight percent and volume percent are different quantities and cannot be substituted. Use the density of the whole slurry under the stated conditions, not the density of pure water or of the solid material alone.
ILLUSTRATIVE EXAMPLE
Apply the reasoning
At an illustrative 12 m³/h, slurry density of 1,080 kg/m³ and 6 wt% dry solids, mass flow is 12,960 kg/h and dry-solids loading is 777.6 kg/h. Using water density would give 720 kg/h, an underestimate of 57.6 kg/h. The error propagates into chemical dose, cake conveying and dryer calculations. These are arithmetic inputs, not a model capacity recommendation.
What to record
| Item | Basis to document |
|---|---|
| Volume flow | m³/h; identify average and peak |
| Slurry density | kg/m³ at the reported temperature |
| Dry-solids fraction | wt% / 100; report the laboratory method |
| Dry-solids mass flow | Q × ρ × x, in kg/h |
Review checklist
- Ask whether a quoted percentage is by mass or volume.
- Include minimum, normal and maximum operating cases.
- Measure density when feed composition changes materially.
- Record whether dissolved solids are included in the analytical result.
Your next decision
Put the converted values beside the original measurements in the RFQ. Both hydraulic flow and dry-solids load can limit a centrifuge, and their maximum values may occur at different operating conditions. For a complete sludge package, carry the same basis through pump, polymer, centrifuge and cake-handling specifications so suppliers are quoting the same duty.