Piperazine Process Flowsheets & Simulations
Explore 2 validated, solved Piperazine simulation flowsheets in MaximaLabs — real components: methane, co2, h2s, water, mdea, pz. Open any one directly in your browser.
Solved via: ENRTL-MDEA-PZ.
Refinery acid-gas treating: MDEA/PZ absorber-stripper
Simultaneous CO2 AND H2S removal from a sour natural-gas / refinery off-gas stream by a piperazine-promoted MDEA solvent — the mixed-amine chemistry legacy tools reach for heavy rate-based/OLI add-ons to model. A high-pressure absorber contacts the sour gas with lean MDEA/PZ solvent (both acid gases absorb into the amine); the rich amine is heated and let down to a low-pressure steam stripper that drives the acid gases back off as a concentrated acid-gas stream and regenerates the lean solvent. Runs on the new 'enrtl-mdea-pz' electrolyte package: a generalized speciation (MDEA protonation + piperazine carbamate/dicarbamate + CO2/HCO3-/CO3-- + H2S/HS- + water) with Davies activity — it correctly reproduces piperazine's promotion (the blend holds more CO2 at a given partial pressure than MDEA alone). Honesty notes: this is an EQUILIBRIUM capacity/selectivity model — NOT rate-based, so PZ's kinetic CO2 promotion and MDEA's kinetic H2S-over-CO2 selectivity are not captured; the absorber/stripper are Kremser shortcut columns; the PZ carbamate constants and the H2S path are screening-grade (see flowsim/solver/thermo/enrtl_blend.py); and the lean-amine loop is left OPEN (the regenerated solvent is a product, not closed back onto the absorber — the same honest simplification the 'co2-from-natural-gas' example makes), with makeup steam as the reboiler surrogate. What it genuinely computes: deep sweetening of the gas, the rich CO2/H2S amine loadings, the concentrated acid-gas overhead, and a fully regenerated lean solvent.
10 unit ops • ENRTL-MDEA-PZ
20 0
View & openRate-based reactive amine absorber (packed, MDEA/PZ)
A packed acid-gas absorber sized the way ChemSep / Aspen RateSep size one -- by real mass-transfer rate over a PACKED HEIGHT, not an assumed stage count. Sour gas (CO2 + H2S in methane) contacts a piperazine-promoted MDEA solvent in a structured-packed column, and the recovery of each acid gas is set by three coupled pieces of physics: the Onda-Takeuchi-Okumoto (1968) gas/liquid film coefficients and wetted area over the packed height (the rate), a reaction-enhancement factor on the liquid film from the Hatta number (the reaction speeding up liquid-side transfer), and the reactive vapor-liquid equilibrium from the electrolyte 'enrtl-mdea-pz' package (the capacity). The result is a genuine design curve: CO2 recovery climbs from ~85% at 0.3 m of packing to pipeline spec by ~1.5 m (5 ppm CO2, 3 ppm H2S) -- run the built-in packed-height sweep to see it. A revealing rate-based insight the equilibrium-stage shortcut can't give: the fast amine reaction makes the liquid resistance negligible, so this absorber is gas-film-controlled -- recovery barely moves with solvent rate but scales directly with packed height. Honesty notes (see flowsim/solver/unitops/rate_based_absorber.py): dilute-absorption HTU-NTU with a lean-solvent Colburn form, mean-property diffusivity, a pseudo-first-order (Ha/tanh Ha) enhancement with no instantaneous-reaction cap, and screening-grade reaction rate constants -- it captures the real rate-based behaviour (recovery vs. height, gas-film control) without claiming RateSep-grade rigor. The companion 'mixed-amine-acid-gas-treating' showcase runs the full absorber-stripper loop with the equilibrium-stage (Kremser) absorber for contrast.
5 unit ops • ENRTL-MDEA-PZ
20 1
View & open