Process refractometers for sugar concentration

A refractometer uses light to measure liquid concentration. An LED sends the light into a sapphire or balf prism. The prism is in contact with the liquid and the light from the LED is reflected back from the liquid surface like a mirror. The angle of the reflected light will change depending upon the liquid concentration. This reflected angle is called the angle of refraction. A refractometer uses a CCD to capture the returned light from the liquid. A shadow will be cast on the CCD and this shadow will move based on the angle of refraction. A refractometer uses the output from the CCD to precisely calculate the liquid concentration based upon the CCD image.

In line refractometers use this same principle as a refractometer mentioned above in How does a refractometer work. The difference is an inline refractometer making this analysis of the CCD image constantly and updating many times per second to give a real time reading of the process liquid conditions. Typically inline refractometers are used for process monitoring and process control so they need to be extremely fast to react to process variations.

All refractometers operate on the same principle, but there are many different versions of refractometers from basic to very sophisticated. A user would select the type needed based on the application, accuracy and budget they have for a refractometer. There are very simple hand held refractometers that are purley held up to the light and using the eye the reading is taken, these are typically low cost and low accuracy and affected by human error. The next level would be a small hand held digital refractometer where the determination of the refractive index is calculated electronically, these come in low, medium and high accuracy and will vary in cost accordingly. There are laboratory and at line refractometers for bench top use and these also come in various accuracies and will be selected based on the application and accuracy needed. Inline refractometers would be the last refractometer type and these will monitor a process continuously, these also have various types and brands and should be selected based on the accuracy required and application.

The term inline process is used when a measurement of a product is required to be done during the manufacturing process. This product could be a liquid or also me a solid material as there are alo technologies to measure solid materials inline. In the case of a refractometer, inline process analysis means analysing the concentration of a liquid during the manufacturing process. This becomes especially important if the manufacturer wants to improve quality or increase yield from the liquid.

Refractometers can be used for sugar concentration analysis both off line in a laboratory or using a hand held device. These are typically used by taking a sample of the sugar in liquid form and placing it on the refractometer. The refractometer will then provide the refractive index or Brix of the concentration. Inline refractometers can also be used for this purpose and are mounted in the tank or pipe and measure the sugar concentration in real time.

Refractometers are used in the sugar industry as they are a fast and reliable way to measure the concentration of the sugar liquor. Sugar refractometers can be used throughout the process and allow the sugar processing plant to control the brix or % sugar concentration after crushing, evaporating and crystallising at various other stages of the process. Refractometers are a cost effective and reliable way to make this measurement.

Refractometers are most commonly used to measure bi-component liquids for concentration strength. These liquids can vary from chemical concentrations to foods and beverages. A refractometer is a primary method of analysis and is therefore a very reliable method of concentration analysis for a very wide range of liquid applications.