Chuck,
I made it past stage one to the review board stage. I don't know how many teams were in the running at that stage, but it wasn't that many. It was after the first cut had come out. It really sucked anticipating the second package in the mail. The day it showed up at my house via Fed Ex my heart was racing. When I opened it and the news was that I was out, it was a real blow.
I need to revise my patent since it was submitted. It was the first patent I've ever drawn up and filed. My patent skills were rudimentary at best when I hastily filed it. I have since filed another unrelated patent and it's formatting is much better.
In my approach to the Barrack problem I proposed using a well known sodium silicate manufacturing technique to dissolve the quartz and leave the pm's behind. The only chemicals required were soda ash, lye, and water. I can only assume the key reason it was rejected was likely due to the sodium silicate disposal issues created when dealing with the process. The silicate has useful applications (Aerogels, refractory, textiles, fire fighting, etc.) but the point that I may have overlooked was the cost of transporting the sodium silicate produced off site.
All in all, it was an exhilarating contest for me, and I'm proud I made it as far as I did.
Steve