Free Chlorine
Free chlorine refers to chlorine present as hypochlorous acid (HOCl) or hypochlorite (OCl-) ion. When the chlorine demand of the water is met, the remaining free chlorine is available for oxidation of contaminants, which is measured by a free chlorine sensor.
Like all halogens, chlorine is a very reactive element. In solution, chlorine occurs in many different molecular forms. When chlorine is added to water, it reacts with organic materials and metals to form combined chlorine. Since combined chlorine is not available for disinfection, this effect is called the chlorine demand of water.
The measurement of free chlorine is one of the most important measurements in the water industry today. These measurements ensure that a sufficient amount of chlorine is available for disinfection purposes and in some cases that the chlorine has been removed.
How is free chlorine measured?
Many are familiar with DPD test kits for measuring chlorine. DPD is a reagent that reacts with chlorine to produce a red color. While DPD test kits may be sufficient for simple applications, this method does not distinguish between free chlorine and combined chlorine in solution. For applications where the concentration of free chlorine is critical for disinfection, the most robust measurement technique is to use an amperometric free chlorine sensor.
An amperometric sensor design consists of two electrodes (anode and cathode), a membrane and a filling solution. These sensors measure a change in current caused by the chemical reduction of hypochlorous acid (HOCl) at the cathode. The current flow of this reduction is proportional to the available chlorine. A membrane and electrolyte help control the reaction. Constant flow rate and pressure are controlled to ensure accurate measurement.
Chlorine
Dioxide Chlorine
dioxide is a neutral chlorine compound. It differs greatly from elemental
chlorine both in its chemical structure (ClO2) and in its behavior. One of the
most important properties of chlorine dioxide is its high solubility in water,
especially in cold water. Chlorine dioxide does not hydrolyze when it enters
water; it remains a dissolved gas in solution. Chlorine dioxide is about 10
times more soluble in water than chlorine. It is not affected by pH and has
excellent residual activity that remains active for hours to days. It does not
interact with ammonia or ammonium. It is effective at cold temperatures. Chlorine
dioxide is one of the most effective disinfection methods in the water industry
today. These measurements ensure effective use of chlorine dioxide for
disinfection purposes as well as other applications. Underdosing can be
ineffective and overdosing results in excess chlorite due to product formation.
It is extremely effective in the control of Legionella bacteria. How is Chlorine
dioxide measured? An
amperometric sensor design consists of two electrodes (anode and cathode), a
membrane and a filling solution. These sensors measure a change in current
caused by chemical reduction at the cathode. A membrane and electrolyte help
control the reaction. Constant flow rate and pressure are controlled to ensure
accurate measurement.
The Neomeris Chlorine Dioxide Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of three different ppm chlorine dioxide measurement ranges for your measurement. The basis here ist the amperometric measurement.Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5 or 0-10ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Chlorine Dioxide 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
Our Neomeris Free Chlorine Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of four different ppm free chlorine measurement ranges. (Determination of free chlorine by amperometric method)Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5, 0-10 or 0-20ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Free Chlorine 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
The Neomeris Chlorine Dioxide Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of three different ppm chlorine dioxide measurement ranges for your measurement. The basis here ist the amperometric measurement.Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5 or 0-10ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Chlorine Dioxide 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
Our Neomeris Free Chlorine Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of four different ppm free chlorine measurement ranges. (Determination of free chlorine by amperometric method)Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5, 0-10 or 0-20ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Free Chlorine 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
Our Neomeris Free Chlorine Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of four different ppm free chlorine measurement ranges. (Determination of free chlorine by amperometric method)Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5, 0-10 or 0-20ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Free Chlorine 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
The Neomeris Chlorine Dioxide Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of three different ppm chlorine dioxide measurement ranges for your measurement. The basis here ist the amperometric measurement.Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5 or 0-10ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Chlorine Dioxide 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
Our Neomeris Free Chlorine Sensors are specifically designed for disinfection applications in water treatment and swimming pools. There is a choice of four different ppm free chlorine measurement ranges. (Determination of free chlorine by amperometric method)Typical further applications are: Industrial waste waterCooling waterBottle rinsingIrrigation water in agricultureand many others.Signal outputThe measured value is easily and reliably transferred to your control or display system by means of a 4-20mA signal with a scaling of 0-2, 0-5, 0-10 or 0-20ppm.MaintenanceThe membrane cap mounted on the sensor, as well as the included electrolyte solution, are easily replaceable by the user. This regular maintenance on the sensor helps to extend the service life in the application and to always obtain an optimal measurement result. MountingThe sensor is mounted in the separately available flow cell and, in addition to this, we offer you the flow meter required for this to ensure stable measurement.Scope of delivery: 1 pcs. Free Chlorine 4-20mA Sensor 2 pcs. replacement cap & brand 2 pcs. 30mL refill solution 3 pcs. cathode polishing squares
Maintenance kit for Neomeris Select chlorine dioxide sensorEnsure proper operation and high measurement accuracy with our chlorine dioxide sensor service kit and also extend the life of the sensor.Content:1x Replacement membrane cap1x Replacement pressure relief strap2x 30-mL bottles of electrolyte refill solution2x 10-mL syringes3x Polishing squares
Maintenance kit for Neomeris Select free chlorine sensorEnsure proper operation and high measurement accuracy with our free chlorine sensor service kit and also extend the life of the sensor.Content:1x Replacement membrane cap1x Replacement pressure relief strap2x 30-mL bottles of electrolyte refill solution2x 10-mL syringes3x Polishing squares
Our Neomeris Select flow cell for free chlorine and chlorine dioxide enables highly accurate measurements by preventing the formation of air bubbles at the sensor membrane while maintaining laminar flow across the membrane.Our flow cell is fully compatible with free chlorine and chlorine dioxide sensors. Allows for highly accurate measurements: Maintains laminar flow through the system and prevents air bubbles from forming, increasing measurement accuracy.Easy sensor installation: Mount your free chlorine or chlorine dioxide sensor in the flow cell in less than 5 minutes.