Self cleaning cell for selective analysis of reducing substances, low and high concentrations, Mod.606
Sensors for reducing substances (metabisulfites, sulphites, sulpur dioxide...) in aqueous solutions including special electrodes and peculiar operating features; their selectivity, sensitivity, accuracy and reliability cannot be easily found in other analysers presently available in the market.
The mechanical electrodes de-passivation system allows the use of these cells in all those applications where traditional cells could not work because of the presence of fouling substances that would deposit on the electrodes rapidly making the measure unreliable.
Mod.606 cells have been designed for applications where selective and accurate reducing sudstances analysis is a basic issue because the concentration to be detected is very low, or very high, or because high reliability for long operating periods with no maintenance needs is required. Another typical application of this cell is for reducing substances measurements in sea water.
These sensors are made of a polycarbonate through flow chamber that houses the measuring electrode, the counter electrode, the reference electrode, the optional temperature sensor for measurement thermo compensation and the brush for mechanical electrodes depassivation. The electrodes are directly immersed into the sample that flows in the chamber with a constant flow rate, controlled by the cell itself; the electrodes are kept clean and active by the action of the brush.
The polarization voltage impressed across measuring electrode and counter electrode and the proper amplification factor make the cell selective to different reducing substances. The cell is absolutely free of unwanted effects like corrosion of the electrodes: noises due to these phenomena are so forth completely avoided even in critical applications like sea water measurements, wastewater applications and measures at high concentrations.
The reference electrode can be selected among two versions so that the cell can be used in very harsh applications.
Typical applications of these cells are in food and beverage industry (i.e. for the measure of metabisulphites, sulphur anhydride and sulphites), drinking water plants (i.e. when removing chlorine with a reducing substance) in oenology, in textile industry, in tanneries wastewater treatment plants, in chromium plating wastewater treatment plants.
Materials at contact: PC, PTFE, PVC, Stainless Steel or Hastelloy (instead of Stainless Steel)
Counterelectrode and Working electrode, C and W: inert material
Reference Electrode, R (with salt bridge): calomel (for the use in harsh conditions) or silver/silver chloride
Operating temperature Limits: 5 to 50°C
Measuring ranges: 0-2000 ppb, 0-10 ppm, 0-2000 ppm
Power supply: 24 Vac or 110 Vac or 220 Vac; optionally 24 Vdc
Consumption: 3 W
Optionally the brush can be pneumatically actuated. Pneumatic actuator requirements: filtered air, P > 2 bar
Sample flowrate does not affect the measure. It has to be adjusted so to obtain a correct response time and properly representative measure (number of sample renewals per hour) (e.g.20-800 L/h)
Max. salt concentration: no limitation for Cl- concentration
Max.concentration for iron salts Fe(II) and Fe(III): 1 ppm as Fe
Max.allowed sample hardness: 10°f; above this value a frequent electrodes cleaning may be required
These selective cells are used for the measure and control of many reducing substances, such as metabisulphites (or metabisulfites, S2O5=), sulphur dioxide and sulphites (or sulfites, SO3=) in various applications, as in fruit juice processing, in wine (oenology),in IV range products processing, in fruit and vegetables disinfection and processing, in textile industry, in tanneries, in drinking water plants