Turbidity measurement

Turbidimetry is part of industrial photometry, and represents one of the main parameters for determining drinking water quality. Indeed, the clarity and transparency of water are the image of high water quality for most people.

Turbidimeters are used in a wide variety of applications, including :

• Drinking water treatment to check that sedimentation, flocculation, decantation and filtration equipment is working properly;

• wastewater treatment ;

• microbiological research ;

• the food industry:

  • drinks, soups,

  • dairy,

  • cheese dairy, etc. ;

• sulfate analysis ;

• surface treatments ;

• thermal systems for water quality control:

  • control of colloidal silica for boiler and turbine protection,

  • iron particles entrained in steam production from geothermal sites;

• the pulp and paper industry ;

• the semiconductor industry;

• textile industry;

• the chemical and petrochemical industries ;

• various other industries.

Fluid turbidity can be modified by changes in its physical, microbiological, chemical and radiological properties. These changes can have significant effects on the microbiological quality of drinking water, due to the presence of bacteria and viruses. Microbial growth in water is particularly marked on the surface of particles and within low-coherence flocs. There is a coincidence between the existence of pathogenic germs and suspended solids.

Excessive turbidity alters the appearance of treated water and can interfere with the disinfection process and the maintenance of a sufficient chlorine residual in the distribution network.

Turbidity measurement can be used as a substitute for other parameters, for example:

• detection of bacteria and viruses;

• arsenic in natural water, the turbidity of which gives an indication of its content;

• surface treatment water, whose pH measurement (neutralization) is followed by turbidity measurement.

These analyzers are designed for installation at operating sites for continuous water monitoring:

• processes (petrochemical, chemical, etc.);

• of discharges ;

• surface ;

• pluviales ;

• tablecloths.

These waters can be :

• on free surface or in pipelines;

• current or dormant ;

• fixed or variable level ;

• in gravity flow or under pressure.

The matter contained in water is...