RADWAG MAX 60 Moisture Analyzer - Manual (Page 72)

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Liquid substances
Semi-fluid substances are dried in their natural form. Large amount of grease
(fat) occurring in some of substances make moisture content determination
difficult. In such case it is recommended to use
additional components, which increase sample’s
active surface and aid moisture content
releasing process from a sample. such
components are high silica sand, blotting paper
or filter. Before drying a tested substance,
initially dry the additional component, so that its
humidity is close to zero.
Solid objects
Depending on solid object’s structure (dense or loose), moisture content
determining process may take short or long
time. The size of solid’s surface determines
the speed of drying process, and
measurement reliability. Thus, the surface of a
solid object should be as large as possible.
Since solid objects release moisture through
their outer surface, sample thickness is
another important factor.
13. SELECTION OF DRYING PARAMETERS
13.1. Selecting optimum sample mass
Sample mass influences the accuracy of measurement result and
measurement time. Higher mass of a sample, causes higher amount of water
(moisture content) which needs to evaporate, and therefore measurement time
is also longer.
Obtaining short measurement time is feasible in case of small sample mass,
but sample mass cannot be too small, as it may negatively influence required
measurement accuracy.
13.2. Influence of sample mass on measurement result repeatability