Understanding GT Degradation

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When a new, high efficiency, state of the art GT is delivered you will find a degradation curve in your documentation to show your expected output in the upcoming years.

Your future performance outlook might look something like this:

You are looking at Non-recoverable losses from the first day that your Plant is started with expected annual losses of 2 - 5% of your GT output. The Recoverable losses your will regain during an off-line washing but there will be Non-recoverable losses preventing you ever to get back to original output levels. And you may notice that most of non-recoverable losses are taking place before the first Major inspection so its very important to Protect the GT performance very early on.

All that GT degradation - Recoverable and Non-recoverable - is caused by the airborne particles reducing your compressor efficiency by forming deposits on your compressor blading. Those deposits will reduce your compressor efficiency and eat up some of your GT Output. Worst case scenario is the impurities blocking you GT cooling air channels causing your GT blades in your HGP to overheat and might even cause destruction of the GT air cooled blades.

Degradation affects all GT´s - new or old - with F-class filtration

With basic F8 grade filtration you are expecting to have about 18% of the air borne particles reaching your compressor. E.g if your 7FA with F8 filtration is located in a clean urban area with PM10 concentration of just 30 µg/m3 running 4000 hrs/ year your Compressor dust load is about 27 kg/year out of 151 kg/year of airborne impurities sucked into the Inlet Air filter house together with the combustion air.

By upgrading to F8/E11 filtration your filtration efficiency is above 99,2% and your dust loading is reduced to 0,13 kg/year - sufficient to reduce the degradation well below 0,5% / annually.

Adding filtration stages will of course increase your initial dp as there will be more filtration material protecting your GT – but elimination of degradation losses will more than cover the difference:

 

Adding filtration stages will of course increase your initial dp as there will be more filtration material protecting your GT – but elimination of degradation losses will more than cover the difference - this is calculated with only 2% annual degradation, so that is for the plants in relatively clean environment. For all plats situated in heavy industrial zones you can multiply the results by 2 or even 3…

The best thing about EPA filtration upgrade is that it can typically be done without any change to the Inlet air house structures during a normal filter change out - and the ROI is something you can easily approve within your organization.

If you want to know more how Eagle FIlters can help You to protect your GT performance you can always ask our Friendly Filter Sales team or email us at sales@eaglefilters.earth

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