Pulverised coal supply to blast furnace

Pulverised coal is supplied to a blast furnace by a ventilator feed. A delivery pipe leads from a fluidising chamber, into which air is passed through a screen. A loading opening in the side-wall of the tube can be regulated or shut off by a rotating sleeve. It is connected to a hollow operating rod and incorporates calibrated openings which can be lined up with the loading openings. A supplementary loading opening may be set opposite the main opening, and the calibrated openings duplicated, and they may also be fitted with wear resistant bushes. The arrangement reduces loss of precision in the regulating mechanism through wear. Having two opposed loading openings balances the currents of particles further reducing wear.