Aspen HYSYS Polyethylene Production Simulation

Project Brief: Aspen HYSYS Simulation – Polyethylene Production

Simulate two polyethylene production processes in Aspen HYSYS:

Dual Catalyst System

Uses both Ziegler-Natta and Metallocene catalysts

Parallel reactions with 85% ethylene conversion

Product split: 60% from Ziegler-Natta, 40% from Metallocene

Metallocene Catalyst System Only

Catalyst: Bis(indenyl)zirconium dichloride with MAO

Single reaction producing branched polyethylene

85% ethylene conversion

Feed Conditions (both systems):

Ethylene (97.5 mol%), 1-Hexene (5 mol%), H₂ (0.5 mol%), Nitrogen

Temp: 90°C, Pressure: 300 psi, Reactor: Fluidized Bed (CSTR/PFR), Residence Time: 1 hr

Outputs & Specs:

Polyethylene (MW ~200k–500k g/mol), melting point ~130°C

GHG emissions: Ziegler-Natta (5–7 kg CO₂/kg), Metallocene (12–20 kg CO₂/kg)

Process Features:

Cooler (95°C → 70–80°C), 2-phase separator

Recycle loop for unreacted gases, purge 2–5% inert gases

Use Aspen Energy Analyzer for energy & emissions analysis

Deliverables:

Aspen HYSYS files, flow diagrams, energy/emission reports