MaximaLabs
Back to gallery
Cold-storage terminal, Rotterdam, Netherlands

Ammonia refrigeration (−30 °C) — a PENG-ROBINSON process flowsheet

A closed single-stage ammonia vapor-compression cycle serving a −30 °C load: compressor → ambient condenser → JT valve → evaporator. The charge is set via tear_specs; metrics give duty and work (COP ≈ 2). From the ChemSep casebook (Refrigeration_Ammonia-30C).

167 views 1 forks

K0
JT0
Cond0
Evap0
What this showcases
  • Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
  • 3 unit operations modeled: K0, JT0, 2× Evap0.
  • Focus areas: Refrigeration, Closed loop, Ammonia.
Specification
Thermodynamics
PENG-ROBINSON
Components
ammonia
Unit operations
K0JT02× Evap0
Open in workspace

Opens in a new tab, loaded straight into the app — no setup.

Read the step-by-step guide
Python SDK

Reproduce this exact result from Python — the real client.get_example() → run_and_wait() path, not a mockup.

from flowsim.sdk import FlowSimClient

client = FlowSimClient()
example = client.get_example("refrigeration-ammonia-30c")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])

print(result["status"])              # "converged"
streams = client.streams(sim["id"])

Related models

Reference model (ChemSep)

Ammonia refrigeration cycle

A single-stage vapor-compression refrigeration loop using ammonia — the classic industrial (rather than HFC) refrigerant — condensed to subcooled liquid, throttled through a valve, and superheated back to vapor in the evaporator before recycling (inspired by ChemSep's Refrigeration_Ammonia-30C reference case).

Olefins complex, Baytown, Texas, USA

Propylene refrigeration (−30 °C)

Closed propylene cycle for −30 °C process cooling — the workhorse olefin-plant refrigerant. From the ChemSep casebook (Refrigeration_Propylene-30C).

Olefins complex, Baytown, Texas, USA

Propylene refrigeration (−50 °C)

The same propylene loop pulled to −50 °C by sub-atmospheric evaporation (0.8 bar) — COP drops as the lift grows. From the ChemSep casebook (Refrigeration_Propylene-50C).

NGL recovery plant, Permian Basin, Texas, USA

Deep ethane recovery with propane-refrigerated feed chilling

Associated gas is chilled by an external propane refrigeration package before a demethanizer recovers ethane and heavier as NGL bottoms from a methane-rich residue gas overhead — the cryogenic-chilling role Ortloff's CCS/GSP processes play ahead of the turboexpander in a real deep-ethane-recovery plant. The mechanical refrigeration loop itself (compressor/condenser/valve) isn't separately modeled here; the chiller's duty is represented directly as the feed's cooled outlet temperature (the same honest-simplification pattern used for LNG cold-box examples elsewhere in this library).

Reference model (ChemSep)

Propane refrigeration cycle

A single-stage vapor-compression refrigeration loop: propane vapor is compressed, condensed to subcooled liquid, throttled through a valve, and superheated back to vapor in the evaporator before recycling — a small makeup feed and purge close the mass balance (inspired by ChemSep's Refrigeration_* reference cases).

Illustrative refinery sour-water unit

Refinery sour water stripper (NH₃ + H₂S)

The standard refinery sour water stripper: sour water carrying ammonia and hydrogen sulfide is steam-stripped in a 10-stage column, sending both overhead as sour gas and returning stripped water fit for reuse. Runs on the new sour-water weak-electrolyte package, which is what makes the result meaningful — ammonia and H₂S suppress each other's volatility (ammonia raises pH and holds sulfide down as HS⁻; H₂S lowers pH and holds ammonia down as NH₄⁺), and heat reverses both, which is precisely why a stripper works. The two removals come out asymmetric for the real reason: H₂S strips essentially completely while ammonia, five orders of magnitude more soluble, is the duty that sets the steam rate.

Stop fighting legacy software. Build your first flowsheet in 60 seconds.