Phosphates

PO43-

Applications

  • Power Utility
  • Cooling water
  • Drinking water
  • Boiler feedwater
  • Industrial and municipal wastewater
  • Surface water
Phosphates

Description

The 3S colorimeter is a compact analytical instrumentation for online analysis and process monitoring. The colorimeter is based on a color-developing chemical reaction carried out inside the analyzer's glass cell. The sample, coming from an external reservoir or process stream is autonomously grabbed by the instrument and mixed with the appropriate reagents to make the reaction happen. The analyzer uses an LED light source and a photodiode to photometrically measure the developed color intensity (absorbance). The absorbance is proportional to the concentration of the target chemical species (analite).

Features:

  • Low reagents consumption and analytical reliability thanks to our custom designed miniature peristaltic pumps
  • Dual compartment design to guarantee a complete separation between the electronics and the hydraulic section
  • Color touchscreen to show the last measured value clearly, and to set all the options and settings via an user friendly interface
  • Datalogger function with data history in graphical form and USB download
  • Automatic calibration, validation and cleaning to reduce down time and operator intervention, their frequency can be freely set by the user
  • Fully integrable in industrial automation via the analog outputs (2 x 4-20 mA channels), digital output (2 relays + ModbusRTU) and digital input (voltage free contact)

The determination ranges of the phosphate analyzer vary from trace μg/L to 2000 mg/L PO43- using the (optional) internal dilution module. Ranges also depend on the method used.

Method

Molybdate reacts in acid medium with orthophosphate to form phosphomolybdic acid, which is then reduced to intensely colored molybdenum blue. The absorbance intensity is proportional to the phosphate concentration in the sample and is determined at 850 nm.

Features

Measured parameter PO43-

Range

(Ø 26 mm) 0.01 - 4 ppm P-PO4 (12.5 ppm PO4)
(Ø 16 mm) 0.05 - 10 ppm P-PO4 (30 ppm PO4)
(with dilution) 2 - 400 ppm P-PO4 (1200 ppm PO4)

Reproducibility*

* if two values take whichever is greater.
(Ø 26 mm) ± 5 ppb / ± 5%
(Ø 16 mm) ± 10 ppb / ± 5%
Limit of detection 0.01 ppm P-PO4
Wavelength 850 nm
Demineralized water Not required
Interferences Cu(II) (> 10 mg/L) Fe(III) (> 50 mg/L), arseniates, silica (> 20 mg/L)
Reference ISO 6878:2004
Number of reagents 2
Min. analysis time 9 minutes
Default analysis time 15 minutes

Reagent consumption**

** per month, at the default analysis frequency.
(Ø 26 mm) 1.5 L
(Ø 16 mm) 1 L

Reagents and standards

Safety Datasheet

The reagent, containing sodium molybdate and ammonium meta-vanadate in an acid medium, reacts with the orthophosphate to form a yellow coloured phospho-vanado-molybdate compound. The absorbance intensity is proportional to the phosphate concentration in the sample and is determined at 430 nm.

Features

Measured parameter PO43-

Range

(Ø 26 mm) 0.05 - 10 ppm P-PO4 (30 ppm PO4)
(Ø 16 mm) 0.1 - 16 ppm P-PO4 (50 ppm PO4)
(with dilution) 4 - 640 ppm P-PO4 (2000 ppm PO4)

Reproducibility*

* if two values take whichever is greater.
(Ø 26 mm) ± 200 ppb / ± 5%
(Ø 16 mm) ± 500 ppb / ± 5%
Limit of detection 0.05 ppm P-PO4
Wavelength 430 nm
Demineralized water Not required
Number of reagents 1
Min. analysis time 9 minutes
Default analysis time 15 minutes

Reagent consumption**

** per month, at the default analysis frequency.
(Ø 26 mm) 2.5 L
(Ø 16 mm) 1.5 L

Reagents and standards

Safety Datasheet

Technical Specifications

Model 3S-CL
Sampling Mode Batch, with freely settable frequency.
Sample Pressure: Atmospheric
Temperature: 5 ‐ 45°C (41 ‐ 113°F)
Flow Rate: 80 to 500 mL/min
Connection: 6 mm (¼-in.)
Drain Pressure-free drain
Connection: 12 mm (½-in.)
Input Streams 2
Material Epoxy-coated stainless steel AISI 304
Dimensions (H x W x D) 604 x 380 x 210 mm (23.6 x 14.8 x 8.2 in)
Weight 20 kg (44 lbs)
Power Supply Input Voltage: 115 VAC,230 VAC
Power consumption: max. 80 W
Output signals 2 x 4-20 mA analog outputs
Modbus via RS485,Ethernet
Alarms 2 SPDT programmable voltage-free relays
Digital Input None, Online, Start Extra, Skip Idle, Emergency Stop
Ambient Temperature 5 - 45 °C (41 - 113 °F)
Ambient Humidity 10 - 90 % RH (non-condensing)
Protection Grade IP54 (indoor only, outdoor use possible with external cabinet, not included)

Documentation

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