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HANKIN MULTIPLE HEARTH CALCINERS
Calcining, or heat soaking, alters the crystal structure of minerals, producing new, value-added characteristics to the mineral, such as high brightness with low abrasion. Normal temperatures range from 1500°-2100°F for periods of up to 60-minutes. This calls for a furnace capable of reliable, efficient and continuous operation for tens of thousands of hours. The Hankin multiple-hearth calciner is a vertical furnace comprised of alternating in and out hearths. The number of hearths is determined by the desired product rate, the process requirements (for time and temperature), and any pre- or post- temperature conditioning. Material is moved through the calciner by rabble teeth, or plows, driven from a central (vertical) shaft. Top feed, bottom outlet.
- Reliable process rate, product characteristics and efficiency predicted from laboratory evaluation.
- Stationary refractory for maximum thermal insulation and long life with low maintenance.
- Good turn-down ratio and flexibility.
- Accurate control of product residence time.
- Low dust carry-over.
- Minimum operator attention, suitable for automation.
- Small space requirement.
- Burners can be mounted on individual hearths with up to 4 burners per hearth.
- Burner mountings eliminate direct flame impingement on product.
- Burner management provides safe, precise and efficient combustion with accurate control of temperatures and atmosphere.
- Efficient heat transfer produces low heat input per ton of product.
- Feed preparation and product systems can be designed and provided.
- Many installations for various applications providing extensive experience.