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Separation Systems

Selecting the appropriate separation systems and equipment is based on the two-phases you are trying to separate (solid, liquid, gas).  Properties Seperation Method - Distillation Systemof the process mix, and the separation purities/rates that you want to achieve help refine the selection. EPIC’s experienced process team will help you find the best separation strategy by following these steps:

  1. Define your exact system goals (separation rate, purity, volume output, etc.)
  2. Fully specify the process conditions under which separation will occur
  3. Make a preliminary separation equipment selection in consultation with equipment manufacturers
  4. Integrate the system and complete FAT (factory acceptance testing)
  5. Modify process conditions if required.

The basic categories of separation techniques, equipment and important factors are listed in the drop downs below. Talk to an EPIC Engineer today to start designing your modular separation system. View our gallery of select separation jobs completed by EPIC.

Absorption/Stripping (Separation)

Equipment:

  • Packed Columns
    • Flooding curve
    • Pressure drop
    • Column diameter
    • Packed
    • Transfer Units
    • Minimum liquid rate
  • Tray Column
    • Number of theoretical trays
    • Kremser-Brown-Souders Equation for dilute system.

Important Factors: 

  • Diffusion of bulk moving fluid
  • Eqi-molar counter-diffusion
  • Mass transfer
  • Equilibrium solubility curve

Absorption (Purification)

Types:

  • Gas purification
  • Liquid purification
  • Sublimation

Equipment:

  • Stirred tanks
  • Fixed beds (percolation)
  • Moving beds
  • Ion exchange
  • Chromatography
  • Sublimation vessels/cold fingers

Important Factors:

  • Required residence time
  • Stages
  • Molecule size
  • Mass transfer zone size
  • Thermodynamic equilibrium
  • Net loading
  • Desorption
  • Regeneration
  • Pressure and temperature
  • Displacement

Centrifugation (Cyclonic Separation)

Equipment:

  • Centrifuges
  • Microcentrifuges
  • High-speed centrifuges
  • Ultracentrifuges
  • Fractionation
  • Decantation

Important Factors:

  • Sedimentation rate
  • Immiscibility
  • Gravitational force
  • Angular velocity
  • Revolutions per minute

Membranes and Filtration (Separation)

Equipment:

  • Tubular membranes
  • Reverse Osmosis
  • Ultrafiltration
  • Gas separation
  • Electrodialysis
  • Electrophoresis
  • Microfiltration
  • Nanofiltration
  • Pervaporation
  • Membrane contactors
  • Membrane distillation
  • Membrane reactors

Important Factors:

  • Transport mechanism
  • Permeate flux
  • Fouling
  • Concentration
  • Polarization
  • Diffusivity

Read more about EPIC’s experience with Membranes and Filtration Systems…

Precipitation and Crystallization (Purification)

Types:

  • Crystallization
  • Recrystallization
  • Precipitation
  • Fractional freezing
  • Zone melting

Equipment:

  • Tank crystallizers
  • Tubes
  • NMR tubes
  • Induction coils
  • Resistance heaters

Important Factors:

  • Temperature
  • Solubility
  • Precipitation rate/crystallization rate
  • Time
  • Settling rate
  • Nucleation

Demister (Vapor Separation)

Equipment:

  • Mesh Coalescer
  • Vane pack

Important Factors:

  • Residence time
  • Droplet size
  • Vapor quality

Distillation (Separation)

Types of Distillation:

  • Simple distillation
  • Flash distillation
  • Steady-state (continuous) distillation
  • Batch distillation
  • Vacuum distillation
  • Extractive distillation
  • Steam distillation
  • Reactive distillation
  • Fractional distillation
  • Azeotropic distillation

Important Factors:

  • Boiling point elevation
  • Surface tension
  • Vapor pressure
  • Vapor-liquid equilibrium
  • Solubility
  • Maximum achievable concentration

Learn more about EPIC’s experience with distillation columns & systems…

Drying (Separation)

Methods of Drying:

  • Direct/conduction
  • Indirect/convection
  • Radiation
  • Dielectric
  • Freeze drying
  • Steam drying
  • Air drying

Equipment: see our drying unit ops page for a complete equipment chart

Important Factors:

  • Heat source
  • Drying rate
  • Moisture content
  • Heat transfer rate
  • Shrinkage and deformation[/twocol_one_last]

Evaporation (Separation)

Methods of Evaporation:

  • Combustive evaporation
  • Pre-combustion vaporization
  • Film deposition
  • Flash evaporation
  • Pan evaporation
  • Vacuum evaporation
  • Centrifugal evaporation

Equipment:

  • Centrifuges
  • Flash drum
  • Vacuum evaporators
  • Rotary evaporator
  • Vapor-compression evaporator
  • Evaporative cooler
  • Forced circulation evaporator
  • Falling film evaporator
  • Rising film (long tube vertical)
  • Climbing and falling film plate
  • Multiple effect evaporators
Important Factors:

  • Concentration of substances
  • Air flow rate
  • Inter-molecular forces
  • Pressure
  • Surface area
  • Temperature
  • Density
  • Equilibrium
  • Temperature and pressure
  • Spin rate
  • Boiling points
  • Mixture concentration
  • Fugacity
  • Vapor pressures

Gravitational and Mechanical Separation

Method:

  • Elutriation
  • Sedimentation
  • Coaggulation
  • Flocculation
  • Dissolved air flotation
  • Froth flotation
  • Thickening
  • Clarification
  • Deinking
  • Oil-water separation
  • Winnowing

Equipment:

  • Skimming devices
  • Sieves
  • DAF (dissolved air flotation) tanks
  • Baffled tanks
  • Gravity tables
  • Clarifiers
  • Winnowing machines

Important Factors:

  • Density differences
  • Immiscibility/solubility
  • Settling rate
  • Rise rate
  • Flocculation/agglomeration rate
  • Mixing intensity
  • Cluster size

Extraction (Separation)

Methods:

  • Leaching
  • Liquid-liquid extraction
  • Solid phase extraction

Equipment:

  • Unagitated columns
    • Spay columns
    • Packed columns
    • Plate columns
  • Pulsed columns
    • Pulse-packed column
    • Pulse-plate column
    • Controlled-cycling column pulsed mixer settler
  • Mechanically agitated columns
    • Rotary Contactors
      • Mixer settler
      • Scheibel columns
      • Oldshue-rushton
      • Rotating disk
      • Kuhani column
      • Graesser raining-bucket contractor

Equipment Cont.

  • Reciprocating contractors
    • Perforated-plate column
    • Karr column
  • Miscellaneous
    • Static mixer
    • Vibrating-plate
    • Ultrasonic extractor
    • Electrically aided extractor

Important Factors:

  • Feed flow rate
  • Material composition
  • Operating temperature and pressure
  • Recovery requirements
  • Purity of separated substances
  • Solvents
  • Flow rate
  • Number of stages
  • Emulsification and scum formation propensities
  • Interfacial tension
  • Phase density difference

Magnetic Separation

Equipment:

  • Wetherill’s magnetic separator
  • Electromagnets
  • High intensity magnetic separators

Important Factors:

  • Draw rate
  • Magnetic attraction strength

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