Aerodynamics affecting electrostatic precipitator

[SA07]

Hi

Has someone encountered aerodynamics affecting performance of electrostatic precipitator using coal/bagasse as fuel? What have you done to solve the problems?

We have 2 ESP one is working well and the other not. We suspect a problem of gas flow through the ESP.

May a computational flow dynamics help to solve our problem? Thks

Rgds

 

[hacksaw]

Not likely, but you do need to draw up the layout of the duct work, and careful study of internal designs of you ESPs. Good luck, a lot of details to go through.

you might also consider performing flow velocity profiles at the inlets and discharge for a start...

 

[RVAmeche]

Has something changed recently, where both ESPs were working well previously?

Are they tied into the same ductwork or are they on different boilers?

 

[hacksaw]

When often do you clean them,

 

[SA07]

Can you plz send me docs on how to perform flow velocity profile at the inlet and outlet? Then what was done to solve the problem in case the flow profile is not good?

The 2 ESPs worked well just after construction ie after 2007 for a few years. Then later performance deteriorated. This year in May we did the annual maintenance. We repaired holes in the casing. ESP 1 improved much. ESP 2 still not good on bagasse. On coal it is ok. The ESPs are on 2 separate turbo alternator boiler sets. They are not tied to the same duct work.

The ESP is cleaned continuously using rappers. We have put same settings of rapping on ESP 2 as ESP 1 ( which is working well) but still not good.

The 2 ESPs are identical.

The operating values of current, kV and mA on the electrical panels are ok. They work around 50 kV and 500 mA

I have seen in the literature that 2 problems affecting ESP performance are sneakage and hopper sweepage. Do you have docs how to eliminate these?

 

[hacksaw]

you might take a look at thios for example,

https://library.e.abb.com/public/88c1d287593837a2c1257c4a0048b02e/AT_FLOW_002-EN.pdf

In the mill ESP's, we had to water wash from time to time, the shakers worked, but there was always loss of ESP efficiency over time. It has to do with the particulate buildups