Plumb-and-play chlorine dioxide analyser

Paul Boughton

The CDA-22 Chlorine Dioxide Analyzer from Electro-Chemical Devices Inc (ECD) simplifies the monitoring and control of Chlorine Dioxide (CIO2) in applications for the food and beverage industry, including clean-in-place (CIP) sanitising and rinsing operations.

With a panel mounted plumb-and-play design and automatic flow control, the CDA-22 is a low maintenance, complete Chlorine Dioxide measurement system.

Chorine Dioxide (CIO2) is used for microbiological control in many sectors of the food and beverage processing industry including meat, fish and dairy processes, brewing and bottling, and fruits and vegetables. It is a proven and efficient disinfectant, virucide, fungicide and odour neutraliser.

Chlorine Dioxide is highly effective as a final sanitising rinse in CIP systems, due to the fact that it breaks down quickly into inert compounds and leaves no toxic residues. The CDA-22 is designed to measure Chlorine Dioxide in concentrations ranging from 0.05-20 ppm CIO2; as a sanitizing rinse for CIP systems, it is typically used in concentrations between 2 and 5 ppm.  

The CDA-22 Chlorine Dioxide Analyzer is easy to install and maintain and can run for up to one year between electrolyte/membrane changes. It incorporates a CIO2 sensor, automated flow control device and analyser/controller mounted on a PVC panel. Installation is complete after connecting the sample and drain lines, power and outputs, and calibration is accomplished with DPD comparison.

The CDA-22 features a polarographic gold/silver PTFE membrane amperometric CIO2 sensor. While these types of sensors are flow sensitive, the CDA-22’s output is virtually flow independent at values greater than 0.5ft/sec.  The CDA-22’s 'constant head' flow control device maintains the sensor’s optimum flow over a wide range of incoming sample flow rates, from 10-80gal/hr.

The CDA-22’s sensor operates at a wide temperature range of 0 to 100ºC (32 to 212ºF). Because temperature affects the CIO2 permeability of the PTFE membrane, increasing the temperature increases the output of the sensor about 4% per Cº. The chlorine flow cell includes a temperature sensor that allows the C22 analyser to perform automatic temperature compensation of the measurement.

The CDA-22 features a 2.5-x1.75-inch backlit LCD display, with four lines for text and graphics. It requires no expensive reagents and eliminates pressure regulators and rotometers. The CDA-22 offers dual measurements, an XY graphical plot and an optional PID Control Output. The analyser provides a 4-20 mA output proportional to the Chlorine Dioxide measured and two alarm relays SPDT 230VAC/5A or 30VDC/5A resistive max. It features the options to include additional 4-20mA outputs for pH or temperature and up to six additional relays.

For more information, visit www.ecdi.com

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