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Residual Sulfite Monitor

A better way to control de-chlorination

ATI Model A15-66

Removal of chlorine or ozone from water is commonly undertaken in the treatment of potable water and process water. Typical applications include the removal of chlorine from town’s/mains water prior to using Reverse Osmosis (RO) membranes. Many water plants follow ozone treatment with a Granular Activated Carbon (GAC) plant. It is important that ozonated water does not go onto the GACS filter. Dechlorination of  wastewater effluent is also  common practice in many treatment facilities, eliminating chlorine residuals that may be toxic to fish in the receiving stream. As the discharge limits of residual chlorine are near to zero the monitoring & complying of such values has become difficult, controlling residuals at values between zero and a few hundred parts-per-billion is often not achievable.

The residual sulphite monitor solves this issue and provides the solution to dechlorination control. It provides a measure of excess sulphite, if there is excess sulphite there can be no chlorine or ozone in the water.

Features and Benefits:

  • Direct Sulfite Measurement: Sulfite ion is measured selectively by conversion to sulfur dioxide. Easier to control to a small sulphite residual than to zero chlorine
  • Low maintenance and automatic cleaning: the monitor provides a system for controlling the automatic cleaning of sample inlet line to control fouling.

Technical Specifications:

Electronic Monitor

  • Accuracy: ±0.03 PPM
  • Repeatability: ±0.01 PPM
  • Linearity: 0.1% of FS

Chemistry Module

  • Sensor: Membraned SO2 gas sensor
  • Sensor Cable: 25 ft standard, 100 ft maximum
  • Response Time: 95% in 3 minutes

Please download the technical documentation for further details.