Reply To: ACC max capacity

Ockert Augustyn

I’d like to add that an ACC can handle whatever you give it (obviously within reasonable limits), the question is what saturation temperature you will operate at. If you increase steamflow, you’ll produce more MW but you’ll pay for it in efficiency if your ACC was not designed for it. Usually in our case, the turbine last stage blades have some limit and you shouldn’t operate at higher values than that. Sometimes, we find that even at design steamflow, our backpressures are so high (because of wind etc.) that we have to “deload” i.e. reduce steam flow.

Cleaning tubes (the presence of fouling), changing fan pitch etc. all just try to help you to get the saturation temperature down for a given heat load and that could change over time for various reasons.

In our case, which is not combined cycle, only coal, you can increase steamflow until you reach a upper backpressure limit – then you’ve reached “capacity” but obviously you’re less efficient (burning more coal) at that specific operating point.

The best way to know is to run it up slowly and see what happens ­čÖé