Why Bentonite Is Costing Your Pellet Plant More Than You Think

The Bentonite Trap

Bentonite is cheap. That is the whole pitch. Except that is the wrong way to think about it. Bentonite's true cost is hidden in the chemistry it disrupts, the process problems it creates downstream, and the quality penalties it imposes on the final steel product.

The Sulphur Problem

All bentonites contain pyrite impurity. When bentonite is added to the pellet mix, this sulphur goes into the furnace with the ore. A typical bentonite addition rate of 0.8-1.2% introduces 0.5-1.5 kg of sulphur per tonne of pellets.

The Chemistry Disruption Problem

Bentonite is silica-based. When it melts in the induration furnace, it forms silicates that coat the surface of iron oxide particles. This coating interferes with reduction reactions in downstream processes - whether a DRI kiln or a blast furnace.

The ACL Alternative

ACL's organic agglomeration binder systems are sulphur-free, low-dose, and chemically designed to complement rather than interfere with iron reduction chemistry. While the per-tonne binder cost is higher than bentonite, the downstream savings in coal consumption and process efficiency mean the net impact on the plant's P&L is strongly positive.