A Comprehensive Theoretical Model for Dust Explosion Hazard Assessment and Prevention in Nigerian Flour Milling and Grain Processing Facilities

Dust explosions in enclosed flour milling, grain processing, and agricultural commodity handling facilities represent a severe and underappreciated industrial hazard in Nigeria, where rapid growth in processing facility capacity has not been matched by advances in explosion hazard assessment methodology, prevention engineering, or regulatory framework, creating conditions for potentially catastrophic industrial accidents in facilities serving millions of urban consumers. This research develops a comprehensive theoretical model integrating dust explosion phenomenology, turbulence-modulated flame propagation theory, and probabilistic risk assessment into a unified framework for dust explosion hazard assessment in Nigerian grain processing facilities. The theoretical model derives from first principles the coupled effects of dust concentration, particle size distribution, turbulence intensity, and enclosure geometry on deflagration pressure development and rate of pressure rise, producing dimensionless scaling relationships applicable across the range of enclosure configurations and grain dust types encountered in Nigerian facilities, including maize, wheat, sorghum, and rice dust. Experimental validation of the theoretical scaling relationships is conducted in a 1-cubic-metre laboratory explosion vessel using dust samples collected from five Nigerian flour mills in Kaduna, Lagos, and Kano States. Minimum explosible concentration, maximum explosion pressure, and maximum rate of pressure rise are measured and compared against model predictions. The theoretical framework is applied to six case study facilities to generate quantitative explosion risk profiles and ranked prevention recommendations. The model provides a theoretical foundation for development of Nigeria-specific dust explosion prevention standards. Keywords: dust explosion, flour milling, explosion risk, flame propagation, grain processing Nigeria.