SEPARATION

**Definition:** This place covers:

Processes and apparatus for evaporation, distillation, sublimation, crystallisation, solvent extraction, chromatography, sedimentation, filtration, dust precipitation, gas cleaning, absorption, adsorption, separation of isotopes.

Cold traps, cold baffles.

Treating liquids by displacement, adsorption, separation or degasification.

Treating gases or vapours by separation, recovering, chemical or biological purification of waste gases.

Separation using semi-permeable membranes, dialysis, osmosis, ultrafiltration.

Separation of suspended particles from liquids by sedimentation, flocculation, settling, filtration or other processes.

Separation of dispersed particles from gases or vapours, by filtration, gravity, inertia or centrifugal forces, or using liquid as separating agent.

Similar processes which are not concerned with, or limited to, separation.

**Limiting references (this place does not cover):** - Separating solids from solids by wet methods -> B03B , B03D - Separating solids from solids using liquids or using pneumatic jigs or tables -> B03B - Magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields -> B03C - Flotation, differential sedimentation -> B03D - Centrifuges -> B04B - Vortex apparatus, e.g. cyclones -> B04C - Separating solids from solids by dry methods, e.g. sieving, screening, sifting or using gas currents -> B07B - Presses per se for squeezing-out liquid from liquid-containing material -> B30B9/02 - Making single crystals -> C30B - Into single crystals -> C30B23/00 - Manufacture of hollow fibres -> D01D5/24 , D01F1/08 - Separation of difficult-to-condense gases or air by liquefaction -> F25J3/00 - Condensers -> F28B

**Glossary:** - Filtration: The separation of a fluid-solid mixture, involving passage of most of the fluid through a porous barrier which retains most of the solid particulates contained in the mixture; includes straining solids from fluids. - Filter medium: A porous barrier or porous arrangement of material, which lets a fluid pass while retaining most of the solids which were mixed with it. - Filtering element: A section of filter medium in addition to parts to which the medium is demountably or permanently fixed, including other sections of medium, end caps, peripheral frames or edge strips, but excluding housings. - Filter housing: The fluid-constraining impervious vessel, whether open or closed, which contains, or is adapted to contain one or more filtering elements or filter media. - Filter chamber: The space within a housing where filtering elements or filter media are located; partitions may divide a single housing into a plurality of chambers. - Filtering apparatus: Filtering elements combined with housings, cleaning arrangements, motor or like parts, which are characteristic of the particular type of apparatus. Ancillary devices such as pumps or valves are considered part of a filtering apparatus when inside the apparatus. Ancillary devices performing similar or different unit operations such as comminutors, mixers or non-filtering separators, whether or not inside the apparatus, are not considered part of a filtering apparatus. The term does not extend to apparatus, e.g. washing machines, of which the filter forms only a part.