compartment mill meaning

• [Mechanical engineering]
  "A multisection pulverizing device divided by perforated partitions, with preliminary grinding at one end in a short ball-mill operation, and finish grinding at the discharge end in a longer tube-mill operation."

• compartment:    Noun: compartment& ...
• mill:    Noun: mill &n ...
• closure by compartment:    Noun: closure by c ...

Examples

1. four compartment mill