Hi,

I would like to request please provide me suggestion re following issue:

I am working on power plant which has GE Frame 9E machine with AAF pulse inlet air filters. This unit has no any kind of inlet air cooling system. We installed New filters during last shutdown. During running of GT the pulse cleaning was programmed to run for one hour after mid night and one hour after mid day, while the filter differential was very normal 42 mm of H2O. Pulsing was in service even during rain and then during high ambient humidity say 90%. in few weeks differential started increasing and ten the pulse cleaning remained in service 24 hours, in two months it is now touching high differential alarm.

Here are my questions:
1. Was it right to put pulse cleaning system operative in the midnight?

2. Was it right to put pulse cleaning system operative during heavy rains?

3. Was it right to put pulse cleaning system operative when ambient humidity was between 70 to 90 %?

4. Isn't AAF filter failure due to miss operation of pulse cleaning system?

5. If pulse air dryer become saturated and is not producing air of -25 degrees Celsius, is there chance of increasing diff pressure?

Thanks in advance

 

Is there any kind person who replies my above questions, I would appreciate it, thanks in advance please!!

 

> 1. Was it right to put pulse cleaning system operative in the midnight?

Don't see any problem using at Midnight

> 2. Was it right to put pulse cleaning system operative during heavy rains?

We would certainly not clean during rain or high humidity, it can damage your filters

> 3. Was it right to put pulse cleaning system operative when ambient humidity was between 70 to 90 %?

> 4. Isn't AAF filter failure due to miss operation of pulse cleaning system?

Is the system not operating correctly? Unless the air quality or conditions are wrong, I would doubt if that has caused the deterioration of your filters

> 5. If pulse air dryer become saturated and is not producing air of -25 degrees Celsius, is there chance of increasing diff pressure?

Don't understand -25 deg. C but if your air is not dry it will be a problem

I think it has been pulsing in the rain that has caused your problem

 

i think it depends on filter material. if filter material is of synthetic media, we can clean during high humidity also.

 

Thank you Bob, I got the answer, yes you are right the filters are giving High DP because pulse cleaning was continued in High ambient humidity and rain.

 

Hi, all,

We replaced new intake air filters, and here they are blocking again in less than two months:

Here are facts:

1. filters are from Donaladson,
2. We have very fine dust in atmosphere,
3. Humidity remains between 30 to 85%,
4. Ambeint pressure varies between 1000 to 1010 mbar,
5. We done pulsing for 24 hours, and some time 5 hours but result is same Differential pressure kept rising.
6. Pulse supply air pressure is between 7 to 8 bar.

Please some one help me tell me how can we resolve this issue. thanks in advance.

 

Dear Nawaz,

this sounds like a challenging situation, possibly the filter manufacturer might be able to assist with. The pulse filter system typically does a decent job of cleaning. But with the fine particulate and the high humidity it sounds like it might be too much. I know in many areas users put on "prefilter" wraps over the main filters to catch the debris before it gets to the main filters. These prewraps are cheaper to replace and can be changed with the machine online. The downside is the pulse system cannot be used since it would blow the prewrap off.

Please keep us informed as to what you are able to accomplish. Your problem is not uncommon, I have heard of other sites that operate near coal or oil based units that have similar problems with air contaminate fouling of filter media.

 

I think you should contact Donaldson. I have always found them very helpful. They should be able to look at your location and recommend the correct filter, cleaning cycle etc. Where are you located and what kind of fine dust are you ingesting?

 

Dear,

GT air intake system pulsing based on following condition

Pulse filter dp 3mbar or more than 65%relative humidity or every 24hours this condition most of the plant available

not day or night as you said