Corn Starch (Mining-Grade) Depressant Storage — Caustic-Gelatinized Iron-Mineral Depressant Tank Selection

Storing Starch Depressant for Mining? Start Here

If you're dealing with mining-grade corn starch as a depressant for iron ore flotation, you're working with a key player in the mining industry. This type of starch is a natural polymer used to help separate iron minerals during the flotation process. It's typically gelatinized with caustic soda to enhance its effectiveness. While it's not hazardous, it does require specific storage conditions to maintain its performance.

Can you store it in a poly tank?

Yes, you can store the caustic-gelatinized starch solution in a polyethylene tank. Both HDPE and XLPE are suitable for this purpose, as they handle the mildly basic nature of the solution well. Ensure the tank is designed for chemical storage, with a specific gravity rating of at least 1.0, which is sufficient for the solution's density.

Key Issue: Caustic Gelatinization

The starch solution is typically gelatinized with caustic soda (NaOH) at temperatures between 60-90°C. This process is crucial for activating the starch's depressant capabilities. Therefore, your storage setup should include a stainless steel makedown vessel with a steam-heating coil to maintain these temperatures.

The safety that actually matters

• Ensure tanks and fittings are alkali-resistant to handle the caustic solution.
• Use EPDM gaskets for standard sealing needs.
• Install UV-stabilized coatings for outdoor storage tanks to prevent degradation.

Common questions

Can I use aluminum tanks for storage?

No, aluminum is not suitable due to caustic attack from the solution.

What gasket material should I use?

EPDM is recommended for general use, but always match gaskets to the manufacturer's compatibility chart.

Is it safe to store the dry starch product in poly tanks?

Yes, the dry product is non-hazardous and can be stored in standard poly tanks.