Endress+Hauser HART Proline Promass 83, Руководство по эксплуатации

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Commissioning Proline Promass 83
72 Hauser
6.4.4 Concentration measurement
The measuring device determines three primary variables simultaneously:
• Mass flow
• Fluid density
• Fluid temperature
As standard, these measured variables allow other process variables to be calculated, such
as volume flow, reference density (density at reference temperature) and corrected volume
flow.
The optional software package "Concentration measurement" (F-Chip, accessories) offers a
multitude of additional density functions. Additional evaluation methods are available in
this way, especially for special density calculations in all types of applications:
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85
• Calculating percentage contents, mass and volume flow in two-phase media (carrier fluid
and target fluid),
• Converting density of the fluid into special density units (°Brix, °Baumé, °API, etc.).
Concentration measurement with fixed calculation function
By means of the DENSITY FUNCTION (7000) function, you can select various density
functions which use a fixed specified calculation mode for calculating concentration:
Density function Remarks
%-MASS
%-VOLUME By using the functions for two-phase-media, it is possible to calculate the percentage mass
or volume contents of the carrier fluid or the target fluid. The basic equations (without
temperature compensation) are:
a0004610-en
a0004619-en
D1 = density of carrier fluid (transporting liquid, e.g. water)
D2 = density of target fluid (material transported, e.g. lime powder or a second liquefied
material to be measured)
r = measured overall density
°BRIX Density unit used for the Food & Beverage industry which deals with the saccharose
content of aqueous solutions, e.g. for measuring solutions containing sugar such as fruit
juice, etc.
The following ICUMSA table for Brix units is the basis for calculations within the device.
°BAUME This density unit or scale is mainly used for acidic solutions, e.g. ferric chloride solutions.
Two Baumé scales are used in practice:
– BAUME > 1 kg/l: for solutions heavier than water
– BAUME < 1 kg/l: for solutions lighter than water
°BALLING
°PLATO Both units are a commonly used basis for calculating the fluid density in the brewery
industry. A liquid with a value of 1° BALLING (Plato) has the same fluid density as a water/
cane sugar solution consisting of 1 kg cane sugar dissolved in 99 kg of water. 1° Balling
(Plato) is thus 1% of the liquid weight.
%-BLACK LIQUOR The units of concentration used in the paper industry for black liquor in % by mass. The
formula used for the calculation is the same as for %-MASS.
°API °API (= American Petroleum Institute)
Density units specifically used in North America for liquefied oil products.
D2 · (
r
– D1)
·(D2 – D1)
r
·100% Mass [%] =
(
r
– D1)
(D2 – D1)
·100% Volume = [%]