Process Analytics by Inline Refractometry – PIOX R721


New process refractometer brings laboratory accuracy into the process

In many processes real-time inline concentration measurement is the key to continuous quality control and efficient production. With its new PIOX R721, the newest generation of its process refractometer series, FLEXIM offers for this purpose the most powerful measuring instrument of its kind.

Refractometry – i.e. the measurement of light refraction – is a well-established method of choice for determining the concentration, density and purity of many liquids. In contrast to the refractometers employed commonly in laboratories, PIOX R721 works according to FLEXIM’s patented transmitted light principle. The measurement of light refraction directly in the medium offers highest process safety and accuracy independently of possible deposits on the prism. Moreover, the double prism of the PIOX R721 creates two measuring beams. The difference measurement eliminates external influences and ensures reliable measuring values without drift.

The image sensor in CMOS technology not only converts light signals in digital data, it provides in addition useful diagnostic values: The hight, shape and symmetry of the two light signals recorded by the sensor allow for conclusions about noise, fouling and turbidity and gives useful information about the process itself and about the health of the measurement.

The transmitter calculates application-specific measurement values such as concentration (w% or vol. %), density or °Brix with standard fluid data sets from FLEXIM’s extensive media library. FLEXIM also has an own chemical laboratory which can establish and provide customized fluid data sets. The new transmitter of the PIOX R721 offers bidirectional digital communication: It can be parameterised remotely and supports all commonly used industrial field bus protocols. Via its inputs other fluid parameters such as sound velocity can be read in, allowing for analysis of multi-component media.

The sensor – i.e. the refractometer itself – is available in two different design variants: The chemical design variant offers highest robustness even under the most challenging conditions, the hygienic design variant provides optimum protection against contamination and deposits. Furthermore, for the measurement of extremely corrosive media, a PTFE product variant is available. A multitude of process connections ensure best integration into almost every process environment.

With the new process refractometer PIOX R721, refractometry is ready for Industry 4.0.