The table below shows the advantages and disadvantages of the different methods that can be used to measure moisture content for drying.
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Weight reduction (primary method)
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Electrical characteristics (secondary method)
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Oven method
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IR balance
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Capacitive MC meter
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Resistance MC meter
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Principle
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Evaporation of water at high temperature. Calculation of moisture from initial weight and dry matter weight
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Detection of weight loss by heating and drying
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Grain is filled in between two plates of a capacitor. Water contents affects dialectical properties
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Electrical resistance of crushed grains
Water affects resistance.
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Advantage
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Most exact method
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More accurate than quick moisture meters (0.1%)
Covers full range (0-100%MC)
Automatic operation
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More accurate than resistance type MC meters (0.2-0.5%)
Portable
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Fast readings.
Very portable
Affordable
Rugged
Small sample size
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Constraint
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Expensive oven with temperature control needed
Long process time
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Relatively long process time (10-30 minutes)
Sensitive mechanics
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More expensive than resistance type MC meters
Larger sample sizes
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Lowest accuracy (typically 0.5%)
Limited MC range
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Application
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Reference in research
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Laboratory
Research
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Laboratory and field
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Field and laboratory, grain industry
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