White Liquor (Kraft Pulping Cooking Liquor) Storage — NaOH + Na2S Active Alkali Tank Selection at Integrated Kraft Mills

Storing White Liquor? Start Here

White liquor is a key component in the kraft pulping process, used to break down wood chips into pulp. It's a hot, caustic mixture of sodium hydroxide and sodium sulfide, typically stored at temperatures between 80-95°C. Given its aggressive nature, choosing the right storage tank is crucial to ensure safety and efficiency in your operations.

Can you store it in a poly tank?

For storing hot white liquor, polyethylene tanks are not suitable. The high temperature and caustic nature of white liquor exceed the capabilities of standard HDPE and even cross-linked polyethylene (XLPE) tanks. Industry practice favors carbon steel or stainless steel tanks for this application.

Key Issue: Temperature and Material Compatibility

The high temperature and caustic nature of white liquor can degrade many materials. While carbon steel is the industry standard for tank construction, it's essential to consider the potential for corrosion and material degradation when selecting storage solutions.

The safety that actually matters

• Ensure tanks are made from compatible materials like carbon steel or stainless steel.
• Regularly inspect tanks for signs of corrosion or wear.
• Use appropriate gaskets, such as EPDM, to prevent leaks.
• Maintain proper ventilation to manage any sulfide odors.

Common questions

Can I use HDPE tanks for white liquor?

No, HDPE tanks are not suitable for hot white liquor due to temperature and chemical compatibility issues.

What material is recommended for white liquor tanks?

Carbon steel is the industry standard, with stainless steel used for specific high-erosion areas.

What kind of gaskets should be used?

EPDM gaskets are recommended for their compatibility with hot caustic solutions.