Yamato PULVIS MINI BED GB210B, Instruction Manual

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13. Principle of Operation
Principle of Operation
Refer to " System Chart" on P.37.
The sample is fed from the appropriate container to ⑤ spray nozzle with ⑦ feeding pump.
Moreover, the compressed air pressure from the compressor is regulated by ⑫ needle valve, and
sent to
②
spray nozzle. At the tip of the nozzle, the compressed air mixed with the sample, and
the mixed sample is sprayed inside ‘A’ drying chamber. This sample becomes drop shape that
the particle diameter is approx. 20
μ and the surface area is 3,000 cm
2
per 1 litter of sample.
On the other side, air is suctioned into the unit by
⑧
blower, and heated up till the temperature
set on
①
heater. Since the contact area of the heated air and the sample is very large, the
approx. 90% or more of the moisture will be evaporated in the dry chamber momentarily.
The sample that became fine powder by drying is fed to ‘D’ cyclone under further drying, and
separated from the evaporated part here, and then, fed to ‘E’ container for product. Time after
the sample is sprayed with the nozzle till it is fed into this container does not take 0.5 seconds.
Moreover, since the sample powder is always surrounded with the solvent vapor (moisture vapor),
the temperature does not rise extremely around the particle due to the vaporization heat.
Therefore, in case of the heat-sensitive material such as an enzyme, disintegration can be
executed without dropping degree of activity even under the condition as a temperature around
outlet= 80 Celsius degree.
The evaporated moisture is evacuated to outside via the blower.
The temperature conditions under examination are displayed on the display panel by the inlet
temperature sensor and the outlet temperature sensor. Moreover, the airflow that dries the
sample is measured by the wind velocity sensor in the wind-flow tube, and is displayed on the
display panel.
In case that the sample adhesion to the nozzle tip is outstanding, open ⑩ solenoid valve to let the
pressurizing air blow to the nozzle tip from ‘C’ distributor in order to remove the adhesives. If
necessary, remove ‘B’ cap to take the outside air into the inside of the chamber.