Produced Water Storage — Tank Selection for Oil & Gas Production

Storing Produced Water? Start Here

Produced water is a salty byproduct that comes up with oil and gas during extraction. It's a mix of water, salts, and sometimes even small amounts of oil and gas. Depending on where it comes from, it can be quite salty, with some areas seeing salt levels as high as ocean water. Handling this water is a big part of oil and gas operations, whether it's storing it for recycling, disposal, or reuse.

Can you store it in a poly tank?

Yes, you can store produced water in polyethylene tanks, especially HDPE and XLPE, as long as the free hydrocarbon content is low (under 5-10%). These tanks are great for atmospheric storage, but if there's a lot of oil mixed in, you might need to consider other materials.

Watch out for hydrocarbon content

The key issue with storing produced water in poly tanks is the hydrocarbon content. If the water has more than 5-10% free oil, it can cause the plastic to swell. Most surface storage systems are designed to handle water with less than 1% free oil, so they usually stay within safe limits.

The safety that actually matters

• Ensure tanks are rated for the specific chemical environment.
• Check for proper gasket materials using the manufacturer's chart.
• Regularly inspect tanks for signs of swelling or damage.
• Follow all local and federal regulations for storage and handling.

Common questions

What kind of tanks are typically used?

API 12D or 12F welded steel tanks are common, but HDPE and XLPE tanks are used for water-only service.

Is it safe to use poly tanks for sour water?

Yes, but ensure the tanks are rated for H2S vapor resistance.

How do you manage corrosion?

Use coated steel tanks and regularly check for any signs of corrosion, especially in sour environments.