Investigation into the Flow Properties of Coarse Solid Fuels for Use in Industrial Feed Systems

Table 4

Minimum outlet diameter as a multiple of average particle diameter () for a conical hopper containing milled wood pellets and pulverised bituminous coal using TIVAR 88, stainless steel, and mild steel as wall materials.

Material	Minimum hopper outlet diameter/
	TIVAR 88	Stainless steel	Mild steel	Wet mild steel
Milled wood pellets	492	553	557	418
Pulverised coal	582	614	582	495