Back-pressure Steam Turbine – Process Steam

Back-pressure steam turbines or non-condensing turbines are most widely used for process steam applications. Back-pressure turbines expand the live steam supplied by the boiler to the pressure at which the steam is required for the process.

Classification of Turbines – steam supply and exhaust conditions

Steam turbines may be classified into different categories depending on their purpose and working pressures. The industrial usage of a turbine influences the initial and final conditions of steam. A pressure difference must exist between the steam supply and the exhaust for any steam turbine to operate.

This classification includes:

Back-pressure Steam Turbine

Back-pressure steam turbine - schema
Back-pressure steam turbine – schema

Back-pressure steam turbines or non-condensing turbines are most widely used for process steam applications. Steam is a principal energy source for many industrial processes. The popularity of process steam as an energy source stems from its many advantages, which include:

  • high heat capacity,
  • transportability
  • low toxicity

The process steam can be produced by back-pressure steam turbines, which also generate mechanical work (or electrical energy).  Back-pressure turbines expand the live steam supplied by the boiler to the pressure at which the steam is required for the process. A regulating valve controls the exhaust pressure to suit the needs of the process steam pressure. Back-pressure turbines are commonly found at refineries, district heating units, pulp and paper plants, and desalination facilities where large amounts of low-pressure process steam are needed. The electric power generated by the back-pressure turbine is directly proportional to the amount of process steam required.

 
References:
Reactor Physics and Thermal Hydraulics:
  1. J. R. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed., Addison-Wesley, Reading, MA (1983).
  2. J. R. Lamarsh, A. J. Baratta, Introduction to Nuclear Engineering, 3d ed., Prentice-Hall, 2001, ISBN: 0-201-82498-1.
  3. W. M. Stacey, Nuclear Reactor Physics, John Wiley & Sons, 2001, ISBN: 0- 471-39127-1.
  4. Glasstone, Sesonske. Nuclear Reactor Engineering: Reactor Systems Engineering, Springer; 4th edition, 1994, ISBN: 978-0412985317
  5. Todreas Neil E., Kazimi Mujid S. Nuclear Systems Volume I: Thermal Hydraulic Fundamentals, Second Edition. CRC Press; 2 edition, 2012, ISBN: 978-0415802871
  6. Zohuri B., McDaniel P. Thermodynamics in Nuclear Power Plant Systems. Springer; 2015, ISBN: 978-3-319-13419-2
  7. Moran Michal J., Shapiro Howard N. Fundamentals of Engineering Thermodynamics, Fifth Edition, John Wiley & Sons, 2006, ISBN: 978-0-470-03037-0
  8. Kleinstreuer C. Modern Fluid Dynamics. Springer, 2010, ISBN 978-1-4020-8670-0.
  9. U.S. Department of Energy, THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW. DOE Fundamentals Handbook, Volume 1, 2, and 3. June 1992.
  10. U.S. NRC. NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition

See above:

Steam Turbine