Mechanical process engineering involves the changes in material properties (e.g. particle size), and composition (concentration), due to mechanical effects.
Classification is a mechanical separation method for solid compounds. It utilises either, the geometric features (size) or the settling velocities of the individual particles for the separation process.
Sorting is a mechanical separation process in which a solid compound containing different material characteristics is divided into fractions with the same material characteristicst.
Mechanical process engineering in many cases utilises gravity to separate different phases. Gravity can be used to separate a solid phase off from a fluid.
As well as gravity, centrifugal force can also be used as the driving force for phase separation processes. The centrifugal force can be generated either by guiding the flow of the fluid, or by rotating vessels (centrifuges).
During filtration, solid particles are separated off by a filter medium from a flowing suspension. Suspensions contain insoluble solids finely distributed in a liquid. Usable filter media are sieves, cloths, papers or bulk solids.
Comminution alters the particle size and shape and the surfaces of solids. Virtually all solids must be comminuted when being mined or processed.
Mixing is the opposite of separating. The materials being mixed may be gaseous, liquid or solid.
Agglomeration is the opposite of comminution. The terms agglomeration, granulation and pelletisation designate the process of particle size enlargement of solids.
The term “bulk solids” generally refers to materials in the form of collections of single or individual particles.
A fluidised bed involves two phases: a solid and a fluid (gas or liquid).
Pneumatic conveyor systems transport powderous and granular bulk solids by means of a gas flow (mostly air) in pipeliness.