Q & A > Question Details
We wish to install strainer on instrument air injection line to be used during regeneration of bi metallic pt Re reforming catalyst to avoid carry over of line material/scale on catalyst surface. Can anyone recommend what mesh size should be installed in strainer?
05/07/2010 A: keith bowers, B and B Consulting, kebowers47@gmail.com
First observation is Why is the Instrument Air line dirty? It SHOULD be immaculately clean. If not, all the instruments in the plant are being severely compromised and damaged. A simple in-line strainer will remove only big 'junk' like nuts, welding rod sections etc. It cannot remove much.
There may be two different requirements embedded in your question. An appropriate system should include both fine mesh 'depth' type demister pad to remove larger scale trash, and a much finer filter to remove 'dust' sized iron oxide.
A 6" thick fine mesh mister pad will block larger stuff, and a high dirt loading depth type wound cotton filter cartridge'5 micron' with a 5 micron rating will remove fine particles that would plug the catalyst. The number of cartridges required for the flow rate will have to be calculated of course. If analysis of particle size distribution sample from a 'test blow' shows significant amounts of <5 micron fine dust, then you must incorporate even higher performance filter cartridges--perhaps down to 1 micron.