1. A ROTARY DISINTEGRATOR FOR COMMINUTING FRACTURABLE PARTICULATE MATERIAL SOLELY BY IMPACT COMPRISING SPACED WALL MEANS DEFINING A HOLLOW CHAMBER HAVING AN INLET AND A PERIPHERAL OUTLET; MATERIAL IMPACTING MEANS MOUNTED WITHIN SAID CHAMBER AND COMPRISING TWO CONFRONTING ROTARY SUPPORT MEMBERS; A PLURALITY OF IDENTICALLY SHAPED PINS HAVING A CROSS-SECTIONAL SHAPE CONTAINED WITHIN A CIRCUMNSCRIBING RADIUS OF FROM BETWEEN 10-40 MM. AND ARRANGED ON SAID SUPPORT MEMBERS IN RADIALLY SPACED, CONCENTRIC INTERMESHED CIRCLES; SAID PINS EXTENDING PARALLEL TO THE AXIS OF ROTATION OF SAID SUPPORT MEMBERS WITH THE PINS IN EACH CIRCLE BEING CIRCUMFERENTIALLY SPACED FROM ONE ANOTHER; A HORIZONTAL SHAFT CARRYING EACH SAID SUPPORT MEMBER; THE INNERMOST CIRCLE OF PINS BEING RADIALLY OUTWARDS OF ITS SHAFT; MEANS FOR INTRODUCING SAID PARTICULATE MATERIAL INTO THE SPACE BETWEEN SAID SHAFT AND SAID INNERMOST CIRCLE OF PINS; DRIVE MEANS FOR DRIVING SAID SHAFTS IN OPPOSITE DIRECTIONS TO IMPART HIGH SPEED RELATIVE ROTARY MOVEMENT TO SAID SUPPORT MEMBERS AND ALTERNATE CIRCLES OF SAID PINS; THERE BEING AT LEAST THREE CONCENTRIC CIRCLES OF PINS, SAID INNERMOST CIRCLE OF PINS HAVING FROM 8-10 PINS, THE NEXT ADJACENT CIRCLE OUTWARDS HAVING FROM 8-12 PINS AND SUBSEQUENT CIRCLES HAVING AT LEAST 9 PINS; THE CIRCUMFERENTIAL SPACING BETWEEN THE PINS OF THE SUCCESSIVE CIRCLES INCREASING FROM CIRCLE TO CIRCLE OUTWARDLY; SAID CONCENTRIC CIRCLES OF PINS BEING RADIALLY SPACED FROM EACH OTHER BY FROM 10-25 MM.; AND THE CIRCUMFERENTIAL SPACING BETWEEN THE PINS OF SAID INNERMOST CIRCLE BEING FROM 110-220 MM. WHICH IS SUBSTANTIALLY GREATER THAN THE LARGEST SIZED PARTICLE TO BE IMPACTED, WHEREBY ALL OF THE CIRCUMFERENTIAL SPACINGS BETWEEN THE PINS OF EACH CIRCLE OF SAID CONCENTRIC CIRCLES ARE DETERMINED BY THE FOLLOWING FORMULA: