Sensors

Mechanical separation should be easy assuming the rubber is hardened. Float off the rubber, stones glass rocks fall to the bottom. No sensor needed, just a tumbling or shaking process. Check results and adjust length of process, more or less done, from the sound of it.

Quite. Sensor-less operation is the aim.

There is no indication yet of the flowrates of the various components nor of the particle size ranges of each component. These data might suggest further opportunities.

The waste stream would have to be studied carefully to identify characteristics that could be targeted for separation...size, shape, weight, molecular density and other characteristics come into play...

Basically, we are all suggesting with the lack of details on the size & variability of the feed, it is unlikely to find an instrument to detect the difference. So mechanical separation methods have been proposed.

However, IR spectrum absorption might differentiate, expensive but non-contact instrument, using FTIR methods. Hand held units are used at recycle centers to verify alloys, for instance.

Vision systems can be programmed to identify chacteristics such as color, reflectivity, shape, and at speeds up to 40mph. The most elementary of these can be purchased for under $2,000 US. Telemecanique Vision OSI-XUW, for instance.

A cyclone separator would be a more conventional solution, not the cheapest solution if you consider operating cost, compared to a classifier with drop gates actuated by your sensor.

What colours are present in the mixture?

Rubber being black , cast iron or steel penetrated inside the rubber (grey or silver colour) and other debries like stone glass of their respective colours.

So you need to reject rubber & metal when combined, for further processing, but if uncontaminated rubber, that goes to your accepts?

You could screen for any metal using radio frequency or pulse induction, but you’d need other instruments to sort glass or stone, probably density would be a mass sort method, if reflectivity or shape would not be reliable.