I am trying to setup a bin aeration system for a lime silo at a waster water treatment plant. The is my first time trying to design one of these systems. I decided to desing around the aeration nozzles produce by Monitor. There would be 20 of the nozzles on each of two silos. each of these nozzle is meant to flow 4 scfm @ 5 psig. The combined flow for one silo is then 80 scfm @ 5 psig. I have heard two conflicting opinions on whether to operate these nozzles continuously or only when needed. If operated continouosly, then a roots blower would be the best way to go. The problem is that there are no air drying systems that I can find that are meant to be used at low pressures (5 psig).

If operated only when needed then using high pressure compressed dried air stored in a receiver would work fine if followed by a pressure reducing valve. Unfortunateley I can't find a pressure reducing valve that a) goes down to 5 psig & b) state that it is meant for air. Any help would be much appreciated. Has anybody else here designed such a system? What is a typical setup (it's funny, the people at Monitor have no idea what a typical setup is)? keep in mind that the lime is sensitive to moisture, so the air going in has to be dried. ■