chemical process simulation · in the browser

The process simulator that feels like a modern app.

Drag a parameter and the whole flowsheet re-solves and repaints in milliseconds. Define any chemistry in minutes from a 6,275-substance library. Every number carries its source. No desktop install, no dongles, no dialog-box archaeology.

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runs in your browser · on-prem or cloud · built with working chemical engineers

chem-sim.com · FeCl3 chlorination (live plant model)
CRUCIBLE Simulate canvas: a live P&ID flowsheet with glowing streams, equipment bank and a live alarm re-solve 70.2 ms C2 sump 87.6 °C → approaching limit
0substances with full constants
0 mstypical whole-flowsheet re-solve
0automated engineering tests
0azeotrope-validated NRTL pairs shipped

Three rooms. One instrument.

Simulate is the plant. Studio is the chemistry. The Library is the truth. They share one solver, one token sheet, one philosophy: the screen is an instrument, not a form.

01 · SIMULATELive P&ID, not a diagram of one

Engineering-drawing symbols, orthogonal routed streams, and values that roll as they change. Move a feed rate and watch temperatures, duties and conversions cascade through recycles in real time. Steady-state multiplicity alarms and approach-to-limit warnings fire on the canvas, where operators actually look.

Live P&ID canvas

02 · REACTION STUDIOAny chemistry, minutes not weeks

Search the library, pick components (constants auto-fill), write stoichiometry and kinetics, and get a running flowsheet. Fit rate constants straight from batch lab data. Your kinetics are labelled “user” until they are validated, and the label follows every result they touch.

Reaction Studio: define components, reactions and kinetics

03 · DATA LIBRARYEvery value knows where it came from

Critical constants, Antoine vapor pressure, Cp(T) polynomials, formation enthalpies, flammability limits: 6,275 substances, each field tagged with its source. Active chemistry packs show their validation status in plain sight, including what is NOT design-basis yet.

Data Library with sourced physical constants

Depth where it counts

Not a toy. The solver stack underneath the pretty canvas.

VLE that respects azeotropesRaoult, Peng-Robinson with user-fitted kij, UNIFAC, and a fitted NRTL engine with seven azeotrope-validated binary pairs.
Columns, short and rigorousFUG shortcut design with live McCabe-Thiele construction; adiabatic and PH flash; LLE decanters.
True dynamicsHoldup-aware transients, PID / cascade / ratio control, dynamic flash, and PRBS step-testing with SIMC auto-tuning.
Recycles that convergeQuasi-Newton tear solving with warm starts; equation-oriented symbolic mode cross-validates the sequential solution.
Equipment engineeringUA exchangers and HX rating, pump curves and NPSH, pipe hydraulics, valves and the full pressure field.
From lab bench to flowsheetKinetic regression from batch data, balances and degrees-of-freedom analysis, utilities costing and an optimizer.
Chemistry packsSpeciality chemistry (electrolyte speciation, polymerization with MWD) ships as first-class packs; the pack contract is the extension SDK.
ScriptableA Python client drives everything the UI can do, for studies, sweeps and CI-grade regression of your own plant models.

Honest by construction

Simulators are trusted with capital decisions, so CRUCIBLE refuses to bluff. Every number carries provenance. Unvalidated models wear a banner on the canvas itself. Mock data cannot masquerade as plant truth. Your auditors will notice the difference.

provenance: library provenance: user · unvalidated provenance: validated vs plant

pilot program · 2026

Sketch the route before you commit the lab.

We are onboarding a small number of pilot plants, R&D teams and consultancies. You get the full instrument and direct access to the engineers building it.

Request pilot access