Heat exchangers are installed inside lime rotary kilns to increase heat transfer and improve lime quality. HarbisonWalker International has a patent on the three-legged version call a prefoil, and we also make a four-legged version. These heat exchangers are precast to match the kiln’s internal diameter and are shipped as a complete package to ensure ease of installation. Abrasion resistance is the main factor in the selection of refractory products.