Sodium Hypochlorite Tanks | Sodium Hypochlorite Storage Tank

Sodium Hypochlorite Storage Guidelines

An aggressive oxidizer which requires special storage consideration.

Sodium hypochlorite is most often encountered as a pale greenish-yellow dilute solution commonly known as chlorine liquid bleach or simply bleach, used in a variety of applications. When it comes to storing this chemical, the following three factors must be considered:

Product stability.
Temperature.
U.V. protection.

The life of a tank is affected by quality and stability of the Sodium Hypochlorite stored. The sodium hypochlorite must be made using DI or Soft water and contain NO iron or heavy metal contamination. The sodium hypochlorite must always remain STABLE with regards to pH level (11 to 12). Higher temperatures and the lack of U.V. protection contribute to the decomposition of the sodium hypochlorite, resulting in corrosion barrier attack.

Product Storage

Technical Specifications for Sodium Hypochlorite Storage Tanks

Recommended Resin Materials for Sodium Hypochlorite (NaOCl) Storage:

Concentration %	Temperature¹	^{Recommended Resin Materials for Sodium Hypochlorite Storage2}
0.5 – 5.25	≤ 150° F.	Derakane 411
0.5 – 5.25	> 150° F. to ≤ 180° F.	Derakane 510A, B or C
> 5.25 – 18	≤ 120° F	Derakane 411
> 5.25 – 18	> 120° F. to ≤ 150° F.	Derakane 510A, B or C
> 18 – 21	≤ 110° F.	Derakane 510A, B or C
> 21 – 25	≤ 100° F.	Derakane 510A Only

1. Elevated temperatures contribute to chemical decomposition.
2. Belding Tank’s bulk stored house resin is Derakane 411.

CAUTION! The life of a Sodium Hypochlorite Storage tank is greatly affected by the quality of the chemical itself. Tank owners are cautioned to use high quality sodium hypochlorite, to avoid decomposition of the chemical and degradation of the tank.

Veil Materials for Enhanced Tank Durability:

Two-ply C-Glass or Nexus® (Synthetic)

Catalysts Used in Sodium Hypochlorite Tank Construction:

BPO/DMA (Benzoyl Peroxide / Dimethylaniline) in the corrosion barrier

Co/MEKP (Cobalt Octoate / Methyl Ethyl Ketone Peroxide) in the structural layers

Curing Process for Sodium Hypochlorite Storage Tanks:

Hot air post cure after assembly for four hours @ 180˚ F.

Exterior Features of Sodium Hypochlorite Tanks:

If the Sodium hypochlorite tank is to be located outdoors:

Each tank has U.V. inhibitor in the exterior resin layer.
White gel coat should be considered as an option.

Optimal Fittings for Sodium Hypochlorite Storage Tanks:

Belding Tank uses only Integral (neck and flange face molded together) flanged nozzles.

Bolting Material: T-316 S.S. Standard (Titanium Optional)

Gasket Material: EPDM Standard (Viton™ Optional)

Venting Requirements for Sodium Hypochlorite Tanks:

Unless otherwise noted, all tanks are designed for atmospheric pressure only. Belding Tank recommends the vent be equal to or larger than the largest inlet or outlet fitting.

Plumbing Considerations for Sodium Hypochlorite Storage Systems:

Use of flexible connections resistant to sodium hypochlorite –

Allows for lateral and vertical expansion and contraction of the sodium hypochlorite storage tank
Reduces pump and piping vibration stress on the sodium hypochlorite tank

NOTE: Flexible Connections should be connected to the tank flange. Piping, valves and pumps must have structural support independent of the tank.