Refractometry, a mixture of physics, material science, and chemistry, is a method that calculates the composition of known substances by measuring their respective refractive index (RI). The refractometer determines dissolved solids' concentration by making an optical measurement of a solution's refractive index (nD). The refractometer measures the refractive index nD and the temperature of the process medium. The calculation is based on the refraction of light in the process medium, called the critical angle of refraction, using a yellow LED light source with the same wavelength (580 nm) as the sodium D line (thus nD). In most solutions, the concentration of solute in a solvent can be determined by measuring the refractive index nD. The relation between the refractive index and the concentration depends on the solvent and solute, temperature, and wavelength.
Typical examples of industrial refractometry uses are:
- The calculation of the salinity of water to assess its drinkability.
- The analysis of dissolved solids in liquor production in pulp and paper production.
- The assessment of sugar content ratios for food products and beverages.
- The understanding of the hydrocarbon content of motor fuels.
These are just a few examples. There are many more common industrial uses for industrial inline refractometers and thousands of unidentified potential applications.
To discuss your application for refractometers in New England, contact Piping Specialties, Inc. / PSI.
