ANTTI Vacboost M13, Инструкция по установке и эксплуатации

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Antti-Teollisuus Oy 57 408111 03-2019
Vacboost M13
ECONOMICAL DRYING
You must select the operating mode as a compromise between the output and the economy. Applying suitable
methods, you will be able to improve them both at the same time.
Thermal economy
The correct drying air temperature is the most important factor impacting on the efficiency and economy.
Remember the first main rule:
If the amount of air remains the same, raising the temperature will result in higher output and better economy.
As the temperature rises, the drying air's ability to absorb steam is multiplied, and the output increases abruptly.
Under normal air pressure, for example, the following amounts of steam correspond to relative humidity of 100 %.
at 0 °C 5 grams of water in m³ of air
at 20 °C 17 “”
at 30 °C 30 “”
at 50 °C 83 “”
at 60 °C 130 “”
at 70 °C 220 “”
at 75 °C 242 “”
Remember that the lower the relative humidity of the drying air, the faster water evaporates from the corns.
One m³ of the dryer heater's suction air at a temperature of +10 °C, and with relative humidity of 90 %, contains 8
g of water. When iy is heated to +70° C, it expands by about 50 %. This amount of air still contains the same 8 g
of water, corresponding to the relative humidity of 2.7 %. The air almost "sucks" moisture from the corn. Because
the relative humidity of the suction air is less significant, hot air drying is efficient and economical even when it
is raining.
Need to reduce the amount of air
You may have dimensioned your dryer and dryer heater following the standards, but you still may encounter situ-
ations, where the maximum temperature allowed for the heater (maximum nozzle size) will not raise the drying
air temperature sufficiently. In this case, you need throttle the suction opening of the blower so much that the
temperature of the drying air will rise. This way you will be able to improve both the dryer's output and economy.