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LABORATORY EXPERIMENT № 6

DETERMINATION OF LIQUID DENSITY

(THE DENSITIES OF OIL, OIL PRODUCTS AND

FORMATION WATER) UNDER STANDARD CONDITIONS

6.1. The objective of the experiment is: to determine the

densities of liquids (oil, oil product and formation water) under

atmospheric pressure by means of areometer and pycnometer,
calculate the absolute and relative error and study the principle of the

liquid density determination by means of areometer and pycnometer.

6.2 Definitions

Density is one of the most important properties of oil. Density
is the magnitude which numerically equals to the mass of substance

volume unit that is it is the ratio of substance mass to its volume.
3
Density is measured in kg/m .
Density of oil under the temperature 20 °С and atmospheric
3
pressure varies from 700 (for gas condensate) to 980 kg/m and even

3
to 1000 kg/m . The quality of crude oil can be approximately
estimated by its density. The most valuable is low-density oil with the
3
density less than 880 kg/m . As a rule this oil contains more petrol and
oily fractions.
The density of formation water grows up with increasing the
concentration of salts in it and therefore density of formation water

may vary widely. The density of formation water (brine) under
3
3
the concentration of salts 642.8 kg/m can reach 1450 kg/m .
Approximate dependence of formation water density ρ on its salinity
fw

Q is given in table 6.1.
s
In laboratories the density of liquids is determined by means
of areometer or float densimeter and pycnometer.

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