DULCOZERO FCL – Reliable Monitoring of the Absence of Free Chlorine

17.02.2025
Reliable monitoring of the absence of free chlorine is essential in numerous water treatment processes. The breakthrough of even the smallest concentrations of free chlorine can irreversibly destroy membranes in reverse osmosis systems and cause major damage. ProMinent GmbH has designed the panel-mounted monitoring system DULCOZERO FCL for these applications.
DULCOZERO FCL – Reliable Monitoring of the Absence of Free Chlorine

Fast response time, precise measurement, high process reliability - with the new DULCOZERO FCL monitoring system, users can keep a close eye on the free chlorine! (Image source: ProMinent GmbH)

Even after a long absence of free chlorine, it reliably alarms at the lowest chlorine concentrations and contributes to a high level of process reliability.

With DULCOZERO FCL, ProMinent has developed a special algorithm that logically links and evaluates the measurements of the amperometric sensor for free chlorine with the auxiliary measured variables pH and redox. This minimizes interferences in the measurement and optimizes the reliability of breakthrough detection. A chlorine breakthrough is detected in less than three minutes at a low threshold starting at 0.02 mg/l and triggers an immediate alarm, even if no chlorine has been present for a long time.

With clear, uncontaminated water, the system only needs to be recalibrated after three months. This reduces process costs.

Wide range of applications
The all-in-one system is suitable for monitoring the absence of free chlorine to protect the membranes in reverse osmosis processes in the treatment of drinking, service and process water as well as waste water or for the production of ultrapure water in industrial processes. It is also suitable for the discontinuous operation of disinfection systems in drinking and cooling water treatment as well as in pool and wellness areas. It reliably monitors the free chlorine during the emergency chlorination of drinking water in the event of contamination.

One system, many benefits
All DULCOZERO FCL components are clearly arranged on a single panel for simple and space-saving wall mounting: the DULCOZERO DACb measuring and control unit for signal evaluation, a DULCOFLEX DF2a peristaltic pump, a main switch and a modular sensor bypass armature BAMa with sensors for measuring free chlorine, redox and pH value, a flow switch and a dosing module. The calibration assistant of the DULCOZERO DACb controls the calibration and its sequence automatically. The calibration solution can be easily prepared on site. It is provided automatically via the integrated dosing system. This enables convenient calibration even in the absence of free chlorine in the process water. As the calibration intervals extend over several months, all components are low-wear and no chemicals are used to activate the sensor, maintenance and service costs are significantly reduced. DULCOZERO FCL can be integrated into the web-based ProMinent IoT platform DULCONNEX and will be available from the beginning of 2025.

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