4 replies to this topic

[AFFAN]

I am working on as assignments which aims to cater for turbine performance derating during Summer season. 

we have three SGT300 units installed for Power Generation application. Unit power ratings are (ISO) 7.90MW(e). During summer season, the machine power output gets de-rated to a great extent due to high ambient temperature. Typical temperature variations between winter and summer are from 05 deg C to 50 deg C. Due to this derating, machines are not capable of powering the connected load, and it is required to run additional machines to cater the requirement. We are interested in deploying retrofit air cooling or fogging solution to be installed at Combustion Air Intake. This cooled air should result in increased capacity of machine during summer season., also it should not effect metallurgy of the machines, and system should be effective at higher Relative humidity levels. 

 

what can be best solution for this , installing Evaporative cooling system at inlet , however it would have its own limitations depending on ambient temperatures and RH.  Installation of chilling unit to cool air down to low temperatures, however it would be itself quiet power consuming.  Installation of mist fogging system, which spray 10-20 micron water droplets with high pressure at air inlet to bring temperatures down, however this solution can cause trouble to compressor blades. Other factors might be availability of DEMIN water, or increasing filtration level in case of fogging solution.

 

At our plant third turbine is running on very marginal load and if we can switch off one turbine and shift complete load on the running turbines only by augmenting its power through cooling inlet air it would be huge saving. Also we want modification which can be implemented in minimum time

 

Any subject matter expert please provide guideline on the subject, & share if you have prior experience of handling this type of problem or to prepare/ review same sort of assessment for Turbines

 

 

Please let me if you need any data for providing your value able advise. 

 

Thanks and Regards

Edited by AFFAN, 23 August 2019 - 08:38 AM.

[breizh]

Hi ,

You should contact the turbines' manufacturer SIEMENS to explore your options and probably their.

My 2 cents

Breizh

Edited by breizh, 23 August 2019 - 05:34 AM.

[thorium90]

I would agree with Breizh to discuss with Siemens.

I would think for the ambient conditions you describe that high fogging with the fine water droplets is a promising solution. The problem you mentioned on the water droplets on the blades, its a problem that is easily solved with the right engineering and has been done many times in my plants all over the world. Its abit too technical to write in a forum post. There are also quite a number of other turbine power augmentation methods, it seems you are also rather familiar with the possibilities. They are all just as technical as well and its too much to write in a simple forum post. So I would also suggest you talk with Siemens, get a better picture, or engage a consultant to work with you on it.

[PingPong]

(There appear to be two topics on the same subject by the same topicstarter. I had replied in the other topic before I noticed that there were already responses in this topic, so I deleted my response there and post it also here)

 

You have not provided much useful information about the present operation.

 

As you probably know the specified capacity of any gasturbine is always based on air inlet conditions of 15 ^oC, 60 %RH and 101.3 kPa, and a turbine outlet pressure of 101.3 kPa (ISO conditions).

 

 

First you need to quantify the problem so that you know how much % increase in unit performance you need to achieve.

 

What kind of fuel is used in the units?

 

How much power (MWe) do you need to generate in total ?

 

How much power can each SGT300 actually generate at different air temperatures and pressures through the year? Prepare table.

 

What is the air wet bulb temperature (WBT), or %RH, at various dry bulb temperatures throughout the year? Prepare table or graph.

 

At our plant third turbine is running on very marginal load

And how much is that then?

 

 

With evaporative cooling you can only reduce the air inlet temperature close to the WBT, but not quite.

 

With excess fogging you can achieve much more as the excess water will vaporize inside the compressor and thereby provide compressor intercooling. But you need a reliable demin water quality and quantity.

 

To save demin water you could consider two steps: first evaporative cooling, followed by excess fogging.

 

The power consumption of a chiller will depend on the available cooling medium (type and temperature) for its condensor.

 

 

In summary: what is the best solution in your case depends on how much % additional power you need, whether demin water is available, or can in future be produced, and how you could cool a chiller condensor.

 

All options are being used worldwide, and specialized vendors can be found on the internet. Just contact a few.

Contact also Siemens to hear what option they recommend, and what option(s) they do not recommend for the SGT300.

[EverestSciences]

Hello Affan,

 

Trust all is well.

 

I came across your post and thought to chime in and introduce an alternative Turbine inlet air cooling solution that you may have not heard of previously, AKA ECOChill. This technology is a hybrid system that is based on an Indirect Evaporation system supported by an air/water cooled mechanical chiller. The patent system utilizes less parasitics and does not require de-min water since the chilled water does not come in direct contact with the air stream flowing into the turbine. We have a profound experience with Gas turbines in this capacity range and believe we can add value. 

 

Accordingly, we are happy to provide you with a complete performance analysis study, if interested. Please feel free to communicate further on email: mramzy@everestsciences.com

 

You can also learn more about the technology through our website: www.everestsciences.com

 

All the best.

 

Marc Ramzy