Provides comprehensive guidelines for the structural design, refractory lining, and installation of reinforced cement concrete (RCC) shafts used in vertical mixed-feed lime kilns for the calcination of limestone.
Design and installation of vertical mixed feed type lime kiln guide, Part 1: For limestone, Section 2: RCC type shaft
Quick Reference Values
typical height to diameter ratio4:1 to 6:1
min refractory lining thickness calcining zone230 mm
typical insulation brick thickness115 mm
Practical Notes
Ensure uniform sizing and proper mixing of limestone and solid fuel (coal/coke) before charging to prevent localized overheating or under-calcined zones.
Selection of high heat duty fireclay refractories is critical in the calcining zone to withstand the constant abrasion of descending stones and severe thermal cycling.
A circular or elliptical internal shaft cross-section is highly recommended to minimize dead zones and ensure smooth material descent.