The principles of electrode paste baking and consumption in ferroalloy furnaces are fundamentally similar to what we previously discussed regarding “electrode paste baking and consumption in calcium carbide furnaces.” The only difference lies in the baking intervals, which vary according to different smelting varieties and furnace types. We won’t repeat similar content here but will focus on electrode paste consumption issues in ferroalloy smelting processes.
Factors affecting electrode consumption rate include:
(1) Raw materials used in ferroalloy furnaces
①Higher fixed carbon content leads to slower consumption. Materials with higher fixed carbon content require lower furnace charge ratios. With the same ferroalloy product quality, less electrode carbon participates in reactions, resulting in slower electrode consumption.
②Less carbon material means slower electrode consumption. Less carbon material results in less burning loss at the charge surface, less red-hot material, smaller branch currents, higher resistance, slower electrode oxidation when inserted into the charge, and less electrode carbon participation in reactions.
③Lower comprehensive grade of smelting ore leads to faster electrode consumption. Lower grade means more ore consumption per ton of product, more processes, higher specific consumption of electrode paste, and faster consumption.
④Smaller ore particle size and more powder lead to faster electrode consumption. More small-sized materials and powder result in poor charge surface permeability, more red-hot material, shallow electrode insertion depth, and faster electrode oxidation consumption.
⑤Lower metal recovery rate leads to faster electrode consumption.
(2) Product grade Higher product grade leads to faster electrode consumption. Higher grade products require more ore and power consumption per ton, resulting in higher specific consumption of electrode paste.
(3) Operational factors
①More flux adjustment leads to faster electrode consumption. When adjusting flux without carbon compensation, electrodes directly participate in alloy reactions in the crucible reaction zone, resulting in rapid consumption.
②More dry heating and open arc operations lead to faster electrode consumption. These operations expose the electrode arc directly to air, causing rapid oxidation consumption of the hot electrode carbon.
③Higher active power and electricity consumption lead to faster electrode consumption. With fixed furnace dimensions, higher active power means more power consumption and faster electrode consumption, requiring more electrode feeding.
④Shorter electrode working end leads to faster consumption. Shorter working end means shallower insertion depth, easier arc formation, and faster oxidation consumption.
⑤High voltage, low current operation leads to faster consumption. This creates longer arcs, shallow electrode insertion, and easier open arc formation, accelerating oxidation consumption.
⑥Serious furnace bottom rise leads to faster consumption. Without major repairs, accumulated impurities cause furnace bottom rise, reducing furnace depth and electrode insertion depth, leading to easier arc formation and faster oxidation consumption. This requires consideration of major repairs and restart.
