Description

NALFLEET RO Bisulphite – Dechlorination & RO Membrane Preservation

RO.BISULPHITE LIQUID 38-40% is a concentrated liquid designed for dechlorination and preservation of RO and nano-filtration membranes. The product helps protect membrane performance by removing free chlorine and preventing membrane damage during short-term and long-term shutdowns. Because it is easy to handle and highly effective, it is widely used in marine and industrial RO systems.

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Features

• Liquid, easy-to-dose product

• Suitable for RO membrane preservation

• Effective for dechlorination

• Approved by the Norwegian Food Safety Authority

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Benefits

• Helps maintain RO membrane performance

• Highly concentrated formula

• Simple to apply and manage

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Specifications

General

• IMO/EU Hazard Classification: C-9

Physical Properties

• Density: 1.30–1.34 g/ml

• Form: Light yellow liquid

• Odour: Strong sulphur

• pH: 3.7–4.5

Documents:

• (PDF) RO Product Flyer

• (PDF) SDoC and MD for IHM

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Directions for Use

NALFLEET™ RO Bisulphite is used in two main applications: dechlorination and membrane preservation. Both procedures help protect RO systems and prolong membrane life.

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A. Dechlorination

Feed water that contains free chlorine will damage RO membranes if not treated. RO Bisulphite is a 40% sodium bisulphite solution that reacts quickly with free chlorine.

Dosage:
Use 3.66 ml/m³ of RO Bisulphite per 1 ppm of free chlorine.
A chlorine test kit should be used to verify the reduction.

For continuous use:

• Store the solution in a suitable tank

• Dose the chemical with a controlled dosing pump

• Dose as close to the RO unit as possible

If chlorine levels are high, dose the bisulphite before the antiscalant injection point. The two dosing points must be separated to avoid mixing concentrated chemicals.

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B. Lay-Up & Preservation of RO and NF Membranes

Membranes must be preserved whenever an RO or NF system is shut down for more than 24 hours. Without proper preservation, biofilm may form and reduce performance.

Procedure:

1. Clean the RO system according to operational guidelines

2. Flush thoroughly with RO permeate

3. Prepare a 2.5% RO Bisulphite solution

4. Fill the entire RO system with the solution

5. Perform weekly checks

A fresh solution is required if the pH drops below 3 or if the liquid becomes cloudy or changes colour.

Before use, confirm that all plastic materials in the system are resistant to sodium bisulphite. If not, surface cracks may occur.

RO Bisulphite meets the requirements of NSF/ANSI Standard 60.

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Levering i hele Norge

Ålesund Supply leverer NALFLEET™ RO Bisulphite til hele Norge – inkludert Oslo, Bergen, Trondheim, Stavanger, Kristiansand, Tromsø, Bodø og Ålesund.