摘要 |
Pulverised coal feed tanks 13,14,15 are emptied in sequence via a transport line 25 into the hot blast of a blast furnace. Each tank is carried by three load cells 40 whose outputs are summed and differentiated to obtain the actual feed rate. Gas pressure in the tank is controlled in dependence on the actual feed rate so as to achieve a desired feed rate. To reduce the possibility of inaccurate feeding of coal, the outputs of the respective load cells 40 are compared, and if deviation from a predetermined weight distribution over the load cells is detected, feed from the tank is stopped. The load cells may be duplicated in series, and the summed outputs of the two sets of load cells 40a,40b compared to detect malfunctioning of a load cell, again resulting in cessation of feeding from that tank. |