Enter any three values (Steam Supplied, Steam Not Returned, Makeup Water, and/or Condensate Return) into the calculator to determine the missing one. Use totals over the same time period (or use flow rates with the same time basis, e.g., kg/hr or lb/hr).

Condensate Return Calculator

Enter any 3 values to calculate the missing variable (simplified mass balance: Steam Supplied = Condensate Return + Makeup Water; Steam Not Returned is typically close to Makeup Water).





Condensate Return Formula

The following simplified mass-balance relationship is commonly used to estimate condensate return in a steam system when boiler blowdown and other miscellaneous losses are neglected.

\begin{aligned}
SS &= CR + MW\\
CR &= SS - MW
\end{aligned}

Variables:

  • CR is the condensate return (condensate sent back to the boiler/feedwater system)
  • SS is the steam supplied (steam sent from the boiler to the system)
  • SC is the steam not returned (steam “consumed/lost” from the system, e.g., vents, leaks, humidification, steam injected into product). In a simplified balance, SC is typically close to MW.
  • MW is the makeup water (fresh water added to replace the portion of steam/condensate that does not return)

To calculate the condensate return, subtract the makeup water from the steam supplied: CR = SS − MW. If you instead have an estimate of steam not returned (SC), a common approximation is CR ≈ SS − SC.

What is Condensate Return?

Condensate return refers to the process of returning the condensed steam (condensate) back to the boiler for reuse. This process is crucial in steam systems to improve efficiency, reduce water and energy consumption, and minimize the need for makeup water. The condensate is typically collected from various points in the steam system and returned to the boiler feedwater system, where it is reheated and converted back into steam. Proper management of condensate return can lead to significant cost savings and environmental benefits.

How to Calculate Condensate Return?

The following steps outline how to calculate the Condensate Return.

  1. First, determine the amount of steam supplied (SS) over a consistent time period (or as a flow rate).
  2. Next, determine the amount of makeup water (MW) added over the same period (or as a flow rate).
  3. If available, determine the amount of steam not returned (SC). In a simplified balance, SC is typically close to MW.
  4. Finally, calculate the Condensate Return using the formula CR = SS − MW (or approximately CR ≈ SS − SC).
  5. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Steam Supplied (SS) = 1000 kg

Steam Not Returned (SC) = 150 kg

Makeup Water (MW) = 150 kg

Using the formula, the Condensate Return (CR) would be calculated as follows:

CR = SS - MW = 1000 - 150 = 850\ \text{kg}