Out of them, steam turbine solutions are the most commonly used solutions for power generation. There are primary two types of steam turbines – Non-condensing (Back-pressure) Steam Turbine and Extraction Steam Turbine. The first type is largely used for central power generation. These power-only utility turbines exhaust straight to condensers that uphold vacuum conditions at the discharge of the turbine. A range of tubes, cooled by river, lake, or cooling tower water, condenses the steam into (liquid) water. This cooling water condenses the steam turbine exhaust steam in the condenser generating the condenser vacuum. When a small amount of air goes into the system when it is below atmospheric pressure, a moderately small compressor confiscates non-condensable gases from the condenser. Non-condensable gases are comprised of both air and a small amount of the corrosion byproduct of the water-iron reaction, hydrogen.
Non-condensing (Back-pressure) Turbines
Take a look at the below image which indicates that these steam turbines exhaust their entire flow of steam to the industrial process or main steam facility at conditions close to the process heat requirements.
Here the term “back-pressure” denotes to turbines that dissipate steam at atmospheric pressures and above. The specific CHP application establishes the discharge pressure. 50, 150, and 250 psig are the most typical pressure levels for steam distribution systems.
The extraction turbine on the other side contains opening(s) in its covering that enable withdrawal of a part of the steam at some intermediate pressure before condensing the residual steam.
In this case, the steam withdraw pressure may or may not be automatically controlled. Measured extraction allows more steam to flow through the turbine to produce more electricity during the periods of low thermal demand by the CHP system. In utility type steam turbines, there may be various extraction points, each at a specific pressure relating to a different temperature.
As steam turbines play a vital role in power generation, there is a strong demand for the same across the world. From their installation to their maintenance, there are dedicated companies involved into turbines. So, if you’re looking for a back pressure turbine manufacturer, it won’t be a mountainous task. But make sure to choose a reliable player in the industry to achieve power self-sufficiency and sustainability.