Abstract: In order to achieve clean production in the whole process of coal transportation during loading operation in ports, especially two single unit coal blending operation, and to avoid coal spillage and material blockage to the greatest extent while effectively monitoring single unit flow, characteristics of coal blending operation and software and hardware equipment for blending in Huanghua port were fully analyzed. Then, with these characteristics as an example, coal blending process protection program was compiled and early warning system of instantaneous excessive flow in the port was constructed by adopting FactoryTalk control system platform. The results show that the system can fully cover coal blending and loading operation process in Huanghua port, and can realize early warning and control of instantaneous excessive flow for each single machine. The total instantaneous flow quantity of coal blending is basically controlled within the safety performance range of rated capacity of belt conveyors, and phenomenon of coal spillage and material blockage is significantly reduced. Cal blending flow of single machine can be monitored in real time to reduce occurrence rate of heavy load shutdown accidents.

Key words: harbour, coal blending operation, instantaneous flow, excess uarning, Beidou satellite navigation system (BDS)