I agree with the previous post. I'm not sure I completely understand your set up, but it seems you are microfiltering in a feed and bleed set-up. You seem to be describing a typical fouling problem. You will need to find out if you can avoid the fouling. Increasing feed pressure might compact...
You might want to find out what the fouling is. In some cases it can be an inorganic component such as CaSO4 or a phosphate. In both cases adding some acid to the air might help you.
Bleach can be used. However there are some enviromental concerns. With organic compounds, ether extractable chlorinated hydrocarbons are formed. Some of these compounds are carcinogeneous. In Europe discharge limits are being placed on these components,these limits are quite low.(around 100 ppb)
When you talk about erosion corrosion a lot depends on the fluid and its properties. For entrained air in water a practical limit of 5 M/S (15 ff/s) has been proposed. At that velocity you will have an appreciable pressure loss per length unit. In my opinion you want to stay away from that high...
I agree with the previous post. Treatment should include antiscalant dosing and active chlorine removal (NaHSO3). We have been running with 5 and even 10 micron prefilters for quite some time. We basically change the filters every 4 months of use. Pressure drops over the elements are about 1.5...
