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25 ml, four test tubes of capacity 10 ml and eight test tubes of capacity
5 ml. The frequency of rotor rotation from 2000 to 8000 revolutions/
minute is regulated by steps. The separation factor reaches up to 6000.
The time of rotor acceleration to the maximum frequency of rotation

is 8 – 10 minutes. The centrifuge is equipped by electric watch. Its
using makes possible to set the time of centrifugation from 0 to
60 minutes with the following automatic braking. The mass of

the centrifuge is 16 kg).
In the centrifuge, at very proof emulsions, decomposition does
not go to the end and instead of water the enriched emulsion with
less quantity of water is got and besides all mechanical admixtures,

so-called “mud”, are separated.
This method of demulsification is not used in the fields in large
scales because of high cost of centrifuges.

The content of water and mud in oil samples is determined, as a
rule, by means of small centrifuges in field laboratories.
The most commonly used are centrifuges with the drive

from an electric motor with rotation frequency approximately
3000 revolutions/minute and more.
Figure 8.1 shows the centrifuge with test tubes.

During the work with centrifuges with the electric drive it is
forbidden:
- to work without earthing;
- to increase the rotation frequency over the maximum magnitude

(for the centrifuge of LTC-2 (ЦЛН–2) type this magnitude is
8000 revolutions/minute);
- to work with the open covers of rotor and centrifuge;

- to work with glass test tubes at rotation frequency more than 1/2 of
the maximum magnitude (for the centrifuge of LTC-2 (ЦЛН–2) type
this magnitude is 4000 revolutions/minute);
- to place not diametrically opposite the test tubes filled with

centrifugal material (centrifugate).
Besides the centrifuges mentioned above such modern centrifuges
are produced by industry:

1) The portable laboratory centrifuge ОПн-3.02 (the
centrifuge of periodical type with frequency of rotation up to
3000 revolutions/minute (fig. 8.2). It is used for separation of

the heterogeneous liquid systems into fractions (for liquids with

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