In my opinion it isn't worth the effort of recycling the silica sand. Take care not to breath the dust from it for sure. I have found that a fairly high pressure sand blaster pulverizes most of the sand grains and leaves the grains with no weight or cutting edge. And the stuff is cheap. I just go out into the yard or gravel driveway well away from anything with paint or glass and let the sand fall where it may. I try to stand upwind while doing this.
I know of some stainless steel planters the government ordered with a matt finish - sandblasted. The manufacturer must have been recycling sand and had steel particles contaminating it. After these sat out in the weather for a little while all the mild steel that had gotten embedded in the stainless rusted. Looked terrible.