Rotary Kiln Dryer Modernization

Project Background & Overview

An industrial mineral processing plant operating a rotary batch drum dryer for stone drying faced severe operational bottlenecks due to an aging, piecemeal electrical infrastructure. Over years of continuous operation, plant modifications had added individual motor starters, fusible disconnects, and ad-hoc wiring runs scattered across the processing floor.

The plant also operated a separate 120/240V generator solely to power utility circuits, lighting, and office loads. Complete Combustion was engaged to design a turnkey electrical modernization package that would centralize power distribution, unify safety circuits, and eliminate secondary generator fuel costs.

The Engineering Challenge

• Maintenance Complexity & Downtime: Scattered disconnects and starters increased troubleshooting time during unexpected shutdowns.
• Safety Circuit Fragmentation: Emergency stop buttons were wired locally without a centralized, safety-rated control relay, preventing coordinated facility-wide emergency shutdown.
• Utility Generator Dependency: Running an auxiliary generator for utility and lighting loads introduced continuous fuel and maintenance costs.

Engineering Scope Delivered

• Centralized Motor Control Panel (MCP): Engineered a unified MCP combining branch overcurrent protection, motor starters, and pilot controls for the infeed hopper, material conveyors, rotary drum, burner blower, and bagging line into one centralized enclosure.
• Integrated Safety & Pull-Wire Architecture: Designed a CSA-compliant safety circuit featuring field emergency stop buttons, conveyor-span pull-wire switches, and safety-rated relays to isolate rotating hazards instantly while maintaining controlled shutdown sequences.
• Utility Transformation Skid: Replaced the separate 120/240V generator with a dedicated step-down transformer (480V to 120/208V) feeding a new plant distribution panel for lighting, receptacles, and control room equipment.
• Future Capacity Integration: Incorporated a 200A splitter box and spare breaker capacity within the MCP backplate to accommodate future conveyor or processing additions without redesign.
• P.Eng Stamped Drawing Package: Delivered full single-line diagrams (SLD), internal panel wiring schematics, enclosure layout elevations, cable schedules, and complete Bills of Materials (BOM).

Operational Results

• Consolidated all motor control into a clean, maintainable panel, drastically reducing electrical diagnostic time and operational downtime.
• Unified safety interlocks across all equipment, providing predictable, immediate safety trip behaviour compliant with Ontario electrical and safety regulations.
• Eliminated secondary generator operating costs, delivering ongoing fuel and maintenance savings.