Grading Frac Sand

Did you ask the Frac Sand Man?

News for frac sand companies

A horizontal air current has for millennia been used to winnow chaff from a falling curtain of grain. Applying this technique to sand grading, smaller grains of sand would weigh less and would be deflected further by the air stream. A series of parallel slots placed on the far side of the sand curtain receiving trough would collect different weights of sand grains. (assumes that weight is correlated to size)

Or why not make use of a property that is present in inefficient cyclones used to separate particulates from air in a pneumatic conveying system. If a cyclone is set up incorrectly, a quantity of 'fines' get carried over with the exhaust air while the majority of the heavier particulates drop out at the base of the cyclone. The fraction of 'fines' in the exhaust air is increased as the air flow rate is increased beyond the cyclone capacity. If you can calibrate the air flow rate against to the particle size retained in the exhaust air, you should be able to make a crude separation of the bulk sand. This may be sufficient, or your current shake and screen would then be more productive.

I have never seen this feature of cyclones employed deliberately, just flying a kite on this one.

thanks, no body said it was going to be easy!

Photo-Optical Particle Size Analyzer, made by a couple different manufacturers. They claim to get nearly instant results. with out all the shaking and weighing. WS Tyler makes one that I have seen. I haven't seen it in use and I don't think they are cheap.

Thank you very much