Dryer Gas-Side Water Balance: Exhaust Flow and Humidity Pickup Belong Together

Define the Material or Thermodynamic Model

Humidity ratio W expresses water-vapour mass per dry-gas mass in the Vaisala humidity definitions. With conserved dry-gas flow G, the gas-side water pickup is G(Wout − Win). Compare that quantity with an independently defined solids-side water loss.

Review a Hypothetical Comparison

Hypothetically, 100 kg/h of dry air enters at W = 0.010 and leaves at 0.040 kg/kg. The gas picks up 3 kg/h of water. Independently, 20 kg/h of dry solid changes from X = 0.25 to 0.10 kg water/kg dry solid, also losing 3 kg/h. Using the 101 kg/h incoming moist-air total in place of dry-air flow would produce a false 3.03 kg/h pickup.

Keep the Evidence with the Decision

Draw one boundary enclosing the dryer and label each dry-gas and water stream. Keep the dry-solid basis beside X rather than converting one side silently to wet-basis percentages. A disagreement identifies an incomplete account, not automatically a failed dryer.

This steady illustration excludes leaks, accumulation, entrained solids and other evaporating components. Include them when the actual boundary requires them; no exhaust temperature or drying rate follows from mass closure alone.

What dry-gas flow accounts for the stated water pickup without assuming a total humid-gas basis?

This blank worksheet is for your own project. It contains no H M machine trial result.

Customer Questions

Primary References

These references support the technical principles discussed in this guide. The worked examples and review questions are educational.

• Vaisala humidity definitions
• Reference from hmpharmamachines.com