Copper recovery from a leach residue: CCD washing + hydroxide precipitation — a BRINE process flowsheet
A leach residue leaves a heap/tank-leach circuit as a slurry — insoluble gangue solids carrying entrained copper-sulfate pregnant liquor that would be lost to tailings if simply thickened. A counter-current-decantation (CCD) wash train recovers it: the residue is washed with clean water flowing counter-current to the solids across a chain of thickeners, so the dissolved copper is displaced into a pregnant-liquor overflow while the washed solids go to tailings. The new ccd_washer unit op models the whole train in one block via the classic counter-current washing equation f = (R-1)/(R^(N+1)-1) (Perry's §18; Coulson & Richardson Vol. 2): five stages at a wash ratio near 4 recover ~99.9% of the dissolved copper, leaving only ~0.08% with the tailings. The pregnant liquor is then dosed to pH 8, where the copper drops as Cu(OH)2 sludge (the precipitator op on the CRC-cited solubility-product chemistry), leaving a barren raffinate for recycle.
Modeling assumptions & limitations
- 1Ideal equilibrium washing (perfect mixing + constant underflow at every stage; no settling-flux / thickener-area sizing, wash-water short-circuiting or solute adsorption on the solids) and equilibrium Ksp precipitation at a dosed pH (B-dot activity, a dilute-liquor solution-volume estimate) — a screening process-design starting point, the metallurgical-balance level, not a certified settling/reagent deliverable.
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- Rigorous BRINE thermodynamics, solved by the same engine every simulation runs on.
- 2 unit operations modeled: CCD, Precip.
- Focus areas: Hydrometallurgy, Copper, CCD washing, Counter-current decantation, Precipitation.
- Verified fast convergence — a real, measured solve time, not an estimate.
- Thermodynamics
- BRINE
- Components
- water, cu, so4, gangue
- Unit operations
- CCDPrecip
Opens in a new tab, loaded straight into the app — no setup.
Read the step-by-step guideReproduce 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("copper-ccd-wash-recovery")
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
Acid-mine-drainage neutralization: staged lime precipitation
Acidic, metal-laden mine water (dissolved ferric iron, aluminium, nickel and zinc over a sulfate background) is cleaned in a two-stage lime-neutralization circuit — the classic hydrometallurgy / water-treatment precipitation train. Stage 1 doses to pH 4.5, where ferric iron (Fe(OH)3, pKsp 38.6) and aluminium (Al(OH)3, pKsp 33.0) drop out as a sludge while the base metals stay dissolved; stage 2 raises the liquor to pH 9.5, where nickel (Ni(OH)2) and zinc (Zn(OH)2) precipitate, leaving a clarified effluent. Both stages are the new precipitator unit op wrapping the codebase's CRC-cited metal-hydroxide solubility-product chemistry (thermo/electrolytes.hydroxide_precipitation) — dose to a pH setpoint, read off what drops out — the same selective-precipitation workflow a real neutralization plant runs.
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