By using a thermal separator and a vortex mill, a cryogenic grinding system was established in which experiments were performed to grind scrap tire peels into fine powders. The new grinding device is more effective than mechanical mills such as the ACM pulverizer. The cryogenic grinding results also show that rubber products of sizes less than that 50 mu m are difficult to attain. Sharp corners and smooth surfaces were visible on the ground rubber particles that have the much better flowability. The optimal feed rate and size of scrap tire peels were investigated. The characteristics of final rubber products and the energy consumption in the grinding process were examined in detail. The exergy efficiency of the cryogenic grinding system is 10.9%.