Eight-hour nonstop sterilization of spices high in oil content without adhesion


K-company has sterilized powdery or granular food by pneumatic type sterilization system for many years and had some problems as follows:

  1. When powdery or granular forms of certain spices (such as red pepper and paprika) high in oil content are sterilized, adhesion or accumulation of materials has occurred inside the system.
  2. Due to such adhesion or accumulation, the inside of the system required washing every two or three hours.
  3. This led to suspension of the system operation each time washing was performed, which negatively impacted production efficiency.


[Target for improvement] To realize continuous stable operation for eight hours or more, adhesion prevention measures have to be thoroughly conducted.
Trial and error testing was repeated to determine which part and shape of the equipment may cause adhesion and to change them into the ones preventive of such adhesion.
Material preheating effectiveness has also been confirmed.

Factors and solution points

  1. Identification of adhesion and clogging locations and countermeasures
    The pocket of the high-pressure rotary valve was reshaped into a U-shape from the V-shape and the chute just under the pocket was also reshaped into a shape in which adhesion is unlikely to occur. In addition, a remarkable increase in the flow rate inside the pipe and the pocket brought about further adhesion prevention effectiveness.
  2. Installation of the material preheating equipment
    When material at normal temperature is fed, steam condenses on the material surface to easily cause adhesion onto the system. Heating materials by use of the preheating equipment can reduce and prevent adhesion.


Sterilization of powdery or granular food (such as red pepper and paprika) high in oil content

Conventional continuous operation for two or three hours → continuous stable operation for eight hours realized

Stable continuous operation

A remarkable increase in production efficiency realizes an increased production output.