Efficient production of steam and return of condensate are essential to the operation of this and many other industrial operations. |
If steam is not consumed directly by the process as a component input, it is steam's heat of vaporization that is utilized by the operation. Efficient use of steam as a heating medium results in the conversion of vapor to liquid (water). Returning the liquid condensate back to the boiler for conversion to vapor again is a necessary step in the efficient operation of a closed loop system.
Condensate return systems are certainly not high technology, but keep in mind that a steam system may be the lifeblood of not just one, but many operations throughout a plant. Avoiding downtime in the steam system, of which the condensate return system is an integral part, ranks highly on the list of "Important Things for Plant Operations". Condensate return is critical.
Three general methods are employed to move the condensate from a collection vessel, a trap, to the feedwater side of the boiler. Gravity can be used when conditions permit. A pressure motive return arrangement uses steam pressure and a coordinated valve sequence to drive the condensate through the piping system and back to the boiler. Condensate pumps can also be employed as a positive means of moving condensate through the return piping system.
What are some strong attributes of a good and reliable condensate return pump?
- Minimize or eliminate cavitation at high temperatures. Cavitation will impede pump performance and cause premature deterioration of pump and drive components.
- Ability to handle a high load during cold starts through motor and pump design.
- Design and configuration to handle high temperatures without deterioration of pump and motor.
- Develop higher pressure at lower motor speeds for extended service life.
- Avoidance of mechanical seals below water line.
- Consider a single unit with dual pumps for handling high loads and extending service life.