We have in our Frame 7 E gas turbine mist separator blower which is used for exhaust the vapor from lube oil reservoir via vent pipe line. We made extension of vent pipe line in order to exhaust the vapor outside the turbine building. Whereas the exhaust vapor before the extension was inside the turbine building. After this job was completed we faced problem in it which is leaking from flanges as well as accumulated vapor inside the reservoir. we checked the vent pipe line and we found no more vapor coming out. We consulted Hitachi and they replied the mist separator we have is old and stopped this product. Now we have to select new blower. The question is what are the criteria of selection blower with respect with vent pipe line?

 

You haven't provided enough information for us to be of much help.

How do you know the "blower" is not working properly? Do you know that the mist separator elements are clean and functioning properly?

It's not likely that the "blower" has failed, because they are usually centrifugal blowers and they are pretty sturdy. Have you examined the rotating part of the "blower" to see if it's in good condition?

Did this additional piping seem to work for some period of time and then gradually you began to notice the mist separator wasn't working properly? Or, has it not worked properly from the time it was installed?

Do you have a "pressure" gauge/manometer connected to the area at the top of the L.O. tank to be able to measure how much pressure/vacuum is being created by the "blower" on the L.O. tank?

Have you measured the pressure/vacuum on the top of the L.O. tank with the new piping connected to the "blower" and with the new piping disconnected from the "blower"?

When was the last time you opened the mist separator vessel and did an inspection of the internals and any removable elements?

Could it be that the back-pressure of the piping you added to the discharge of the "blower" has prevented the "blower" from exhausting properly?

How long is the total piping run you added to the discharge of the "blower"?

What is the diameter of the "blower" discharge, and what is the diameter of the piping you added to the discharge of the "blower"?

How many elbows in the piping you added to the discharge of the "blower"?

How much vertical rise in the piping from the discharge of the "blower" to the end of pipe outside the building?

Have you placed any kind of screen at the end of the pipe you added to the discharge of the "blower" (to keep birds or other vermin from entering the pipe when the "blower" is not running?

Is there a "goose-neck" at the discharge end of the piping you added to the "blower"?

Have you used a clamp-on ammeter to measure the amount of current being drawn by the "blower" motor to see if it's producing rated horsepower (versus the motor nameplate)? Current is proportional to torque/power; more current equals more power. You might try taking a reading with the new piping attached, and then one with the new piping disconnected, and comparing them. Since this is a centrifugal blower, if the back-pressure is too high then the blower won't be working very hard because it's not moving very much air. In other words, you might find that the current is higher with the piping disconnected. So, don't be fooled by the readings.

You may have just put so much piping and elbows and restrictions on the discharge of the blower that it can't "blow" enough. You might need a larger "blower" and blower motor, but that might create too much suction on the L.O. tank, which can create other problems.

One very large misconception about mist separators is that they don't require any maintenance. They do, depending on the construction. Many have replaceable elements which degrade with time and can cause the mist separators to not function properly.

 

thanks for your information i will conduct site inspection and com by result.

Thanks and Regards.......
Ayed

 

would you please tell me the require information for calculation the performance of the blower.
i will provide you all of it. i need this urgent.
your help is highly appreciated