Unit procedures and operations

A unit procedure is a processing step carried out in one equipment item (or a set of identical items in parallel). It holds a recipe: an ordered list of operations. A batch reactor procedure might charge solvent, charge reactants, heat, react, cool, transfer out and clean in place, all in the same vessel.

FlowState has 98 unit procedures in 15 categories. Each is either Batch or Continuous; the library shows the equipment type and the mode under each name, for example “Stirred Reactor · Batch”. Find them in the Unit Procedures library on the Flowsheet tab (with search), in the Unit Procedures menu, or by right-clicking the canvas.

The catalogue

Vessel Procedures (9)

In a Reactor · In a Blending Tank · In a Receiver · In a Crystallizer · In a Single-Use Mixer · In a Storage Bag (all batch) · Continuous Stirred Reactor (CSTR) · Plug-Flow Reactor (PFR) · Equilibrium Reactor (continuous)

Bioreactions (4, batch)

In a Fermentor · In a Seed Fermentor · In an Airlift Fermentor · In a Single-Use Bioreactor

Centrifugation (6)

Disk-Stack Centrifugation · Decanter Centrifugation · Hydrocyclone · Three-Phase Centrifugation (continuous) · Basket Centrifugation · Basket Centrifugation with Wash (batch)

Filtration (19)

Microfiltration · Ultrafiltration · Diafiltration · Depth Filtration · Nutsche Filtration · Plate & Frame Filtration · Dead-End Filtration (batch) · Rotary Vacuum Filtration · Reverse Osmosis · Nanofiltration · Electrodialysis · Bipolar-Membrane Electrodialysis · Electrolysis Cell · Clarification · Thickening · Screening · Belt Filter Press · Screw Pressing · Granular Media Filtration (continuous)

Chromatography / Adsorption (7)

Packed-Bed Chromatography · Ion Exchange · Mixed-Bed Ion Exchange · Carbon Adsorption (GAC) (batch) · PCC Chromatography · SMB Chromatography · Pressure Swing Adsorption (continuous)

Cell Disruption (1)

Homogenization

Heat Exchange (4, continuous)

Heating · Cooling · Continuous Heat Sterilization · Heat Exchanger (2 streams)

Mixing / Splitting (6, continuous)

Mixing · Bulk Flow Splitting · Component Splitting · Flow Distribution · Flow Adjustment · Spec-Driven Mixing

Drying (9)

Spray Drying · Rotary Drying · Drum Drying · Fluid-Bed Drying · Sludge Drying (continuous) · Tray Drying · Freeze Drying · Agitated Filter-Dryer · Rotary Vacuum Drying (batch)

Distillation / Evaporation (8)

Batch Distillation (batch) · Shortcut Distillation · Rigorous Distillation · Flash · Evaporation · Multi-Effect Evaporation · Liquid–Liquid Extraction · Liquid–Liquid Decanting (continuous)

Formulation & Packaging (2, batch)

Filling · Packaging

Storage & Transport (4)

Transport · Storage (batch) · Pumping · Generic Box (continuous)

Gas Handling (4, continuous)

Gas Compression · Fan / Blower · Vacuum Pumping · Air Filtration

Energy & Environment (8, continuous)

Steam Generator (Boiler) · Steam Turbine · Engine Generator (CHP) · Aeration Basin · Anaerobic Digester · Raceway Pond · Evaporation Pond · pH Adjustment

Crystallization & Solids Handling (7, continuous)

Continuous Crystallization · Grinding / Milling · Shredding · Belt Conveying · Screw Conveying · Silo Storage · Hopper / Bin

Procedure settings

Select a procedure to edit it in the Inspector.

• Procedure: name, description, section, operating mode (batch or continuous), cycles per batch and start offset.
• Scheduling & sharing: cycle With recipe or Independent (with its own period), and run in Own equipment or Share another procedure’s equipment.
• Vent & emissions (vessels): emission model Off, EPA (displacement, heating, sweep) or Raoult headspace venting, vent policy and an optional vent condenser.
• Equipment: tag and type; Design mode (FlowState sizes the equipment) or Rating mode (you set the size and FlowState checks it); units in parallel, staggered sets, maximum working volume and maximum size per unit. The Cost model sets purchase cost from base size, base cost and scaling exponent, or a cost override, plus material and installation factors. Flags include Use across batches, Omit from scheduling, and the CIP skid or SIP panel to use.
• Consumables, labor & hybrid operation: single-use equipment and bag cost, consumables from the library, labour category, QC tests, and surge tanks for hybrid batch/continuous trains.

Operations

The Operations section lists the recipe. Click an operation to edit it; use ⏶/⏷ to reorder and ✕ to delete. + Add operation opens a menu grouped by purpose. The groups depend on the equipment type.

In vessels (reactors, tanks, fermentors, bags):

In other equipment:

New operations are named after their type, for example HEAT-2. Each operation editor has the operation’s own parameters, its Operating conditions, a Scheduling block (see Scheduling) and its Results.

Modelling notes

• Reactions are written on a mass or molar basis with a mass-balance check. Extents can be set by conversion of the limiting reactant, final concentration, residual amount or equilibrium (van ’t Hoff K), and several reactions run in series or in parallel. Heat of reaction is per kg or mol of the reference component, or per kg O₂ for fermentations.
• Kinetics cover power-law, saturation and inhibition terms with Arrhenius temperature dependence, integrated adaptively and stopped on time, concentration or conversion. Profiles are plotted in the operation editor.
• Fermentation supports Monod kinetics, fed-batch, set-point and titrant feeds, chemostat and perfusion, oxygen uptake with a k_La check and air demand, and intracellular products released by cell disruption.
• Distillation: rigorous MESH columns (bubble-point, sum-rates and Newton–Raphson methods, with automatic fallback), multiple feeds and side draws; FUG shortcut design or rating; multi-cut batch distillation.
• Evaporation: multi-effect evaporators with MVR/TVR and IF97 steam tables.
• Membranes and sorption: UF/DF to a target concentration with gel-polarisation flux, RO/NF with osmotic pressure and energy recovery, ion exchange to breakthrough with regeneration, GAC with Freundlich loading, and chromatography with cycles, gradients, collection windows, resin life and PCC multi-column capture.
• Solids and drying: crystallisation from solubility curves, and dryers that dry to a target loss on drying (LOD) with an air balance, heater duty and fan power.
• Energy: two-stream heat exchangers (U·LMTD·F or ε-NTU), pinch analysis, boilers, steam turbines and combined heat and power, configured under Tasks ▸ Energy, heat integration & wastewater….

If no procedure fits, the Generic Box with component splits and reactions can represent almost any step.