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Steam End-User Quiz

The following 20-question quiz will help test your understanding of the Steam System Basics.

Please select the best answer by clicking on the multiple choice answers.  If you answer incorrectly, you will be prompted to try again. 

Pop up screens will be provided for selected questions to reinforce a topic or provide a clue.

  1. Boiler Efficiency is an attempt to identify the amount of fuel energy converted into steam energy.

  2. Boiler efficiency is less than 100% because of losses. For most boilers the most significant loss is known as what?

    Shell loss
  3. Indirect boiler efficiency evaluates boiler performance by measuring and estimating the individual energy losses of the boiler. Identification of the amount of energy exiting the boiler with each loss helps to identify which areas of boiler operation to target for improvement.

  4. Identify a measurement(s) that can help you manage boiler resources.

    Flue gas exit temperature
    All of the above
  5. Which of these aspects are associated with boiler blowdown?

    Is not a necessary activity for boilers.
    Can be fully re-injected to the feedwater system.
    Will often be reduced if additional condensate is returned to the boiler.
    Is often reduced by supplying the system higher quality (cleaner) makeup water.
    Is commonly controlled with simple conductivity control that is verified through additional water chemistry measurements.
    The energy loss of blowdown can essentially be eliminated through the installation of a blowdown thermal energy recovery system.
    All of the above.
  6. Identify the basic principles efficient combustion control are founded upon.

  7. Utilizing an Automatic Combustion Control system generally improves boiler performance when compared to a Positioning Combustion Control system.

  8. Determine the stack loss for a boiler burning natural gas and operating with the following conditions.

    Flue gas temperature of 400°F
    Flue gas oxygen content of 5.0%wet
    Ambient temperature of 70°F
    Combustibles concentration of 10 ppm
    Blowdown rate of 6% of feedwater flow
    Shell temperature of approximately 140°F

  9. An older boiler is operating with a natural gas fuel consumption of $5,000,000/yr. The combustion control maintains a flue gas oxygen content of approximately 4.0%wet over the typical operating range of the boiler. The boiler was not originally equipped with a feedwater economizer. The current flue gas temperature is characterized as 450°F, with an ambient temperature of 70°F, and for the general operating conditions of the boiler. A feedwater economizer manufacturer can supply an economizer for this boiler that will recover thermal energy from the flue gas. The resulting flue gas temperature is predicted to be 300°F for the typical operating conditions of the boiler. Estimate the fuel cost savings potential.

  10. table

    d. $220,000/yr

  11. Reducing steam consumption at the point of use will result in even more savings at the boiler.

  12. Backpressure steam turbines generate power at no cost.

  13. Condensing turbines commonly convert less than 30% of the boiler fuel energy into power.

  14. Evaluating the complicated interactions of steam system components requires skill, knowledge, and real-world experience.

  15. Steam traps are not capable of significant waste.

  16. Steam trap selection should be based on purchase cost and ease of installation.

  17. Evaluating the energy loss associated with missing or damaged insulation is extremely complicated requiring highly trained experts with years of field experience.

  18. Increasing the amount of condensate recovery will generally not have which of the following effects?

    Reduce fuel consumption
    Reduce makeup water consumption
    Improve boiler feedwater quality
    Reduce water treatment chemical consumption
    Require exotic piping materials
  19. Flash-steam in a condensate system is a negligible and necessary part of the operations.

  20. Steam systems that do not have cogeneration components should be operated at a pressure that is just slightly higher than the pressure required by the end-use components.

  21. Select the measurement that CANNOT help manage steam systems.

    Boiler flue gas temperature
    Boiler flue gas oxygen content
    Boiler flue gas combustibles concentration
    Boiler steam load
    Condensate return
    Makeup water flow
    Steam flow
    Steam end-use control parameters
    Condensate recovery temperature
    All of the above