Process Safety in Solids Mixing, Handling, and Processing

10 Process Safety in Solids Mixing, Handling, and Processing 

The dust arising from the mixing or processing of combustible solid materials can form explosive mixtures with air. In the design of plants to handle such 

2 General Design Safety. In addition to taking specific explosion prevention and protection steps, the conditions that can result in a secondary explosion and the frequency of ignition must be minimized. The following are important  

Control of Mechanical Sparks and Friction. Foreign materials (such as tramp metal) that are capable of igniting combustible material being processed should be removed from the process stream by magnetic separators, pneumatic separators, or grates or other separation devices. 

5 Electrical Classification. In those areas of the plant where a hazardous quantity of dust accumulates or is suspended in the air, the area should be classified and all electrical equipment and installations in those areas should comply with Article 502 or Article 503 of NFPA 70, the National Electrical Code, 

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