KROHNE CORIMASS MFC 85 EN - Manual (Page 17)

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Coriolis mass flowmeters measure density and temperature. From these measurements, and
the known characteristics of sucrose solutions, a Brix value can be calculated. As with the
refractrometer, if there are any other components present in the product, then the displayed
Brix value will be only an approximation. This approximation can not be expected to match
exactly the refractrometer’s approximation. This is because the impurities will not necessary
have the same effect on refractive index as they do on density. Solid particles in the product
will not effect how light is refracted passing thorough the rest of the liquid, but they will effect
its density.
If this situation is not acceptable then the GENERAL CONCENTRATION option could be used
instead. Its parameters should be set so that the ‘PERCENT M’ display mimics the
refractrometer. This requires that the product be fully characterised as described in Section
4.3 Case 4.
5.3 Sodium Hydroxide, (NaOH), Concentration
The NaOH algorithm fits the true characteristics of the product to one decimal place (
±
0.1).
However the range of the fit is limited to 10 to 40°C and 0 to 50% solutions. This is not a great
problem for the Titanium MFM 4085 G series flow meters, as higher concentrations and
temperature would corrode the flow tube. (Zirconium meters and the stainless steel are fully
resistant to attack by Sodium Hydroxide).