A New Concept
The Sandcooker thermal sand reclamation system uses a uniquely designed rotary kiln. The kiln is shaft mounted. This eliminates the expensive tire and trunion arrangement of conventional rotary kilns. The patented method uses the cataracting motion of solids in a rotating cylinder. This higher speed of rotation is unprecedented in rotary kilns. At a rotational speed where centrifugal force is slightly less than gravity, the sand is essentially “mechanically fluidized” rather than fluidized by air. At any point in time, one half of the sand is in freefall. Sand inside the kiln would remind a person of looking at a snow globe. The sand/atmosphere intermixing is superior to that provided by fluid beds. The only air required is for combustion. The sand typically comprises less than 10% of the kiln’s volume. The amount of sand retained in the kiln at any point in time is less than one quarter of its hourly throughput, which reduces the kiln’s size, weight, and cost. Further, the VOC’s produced in the preheat section follow the same path as the sand directly into the combustion zone, using all their heat value for heating the sand. Both combustion air preheating and VOC burn-off are intrinsic in the basic design, removing complexity and costs. The Sandcooker is a true energy miser. Best of all, the equipment’s overall design is really very simple. This not only reduces the capital equipment cost, but also makes the Sandcooker thermal sand reclamation system cost effective in regard to installation, operation, and maintenance.