{
  "authors": [],
  "basis": {
    "capacity": "per tonne of polypropylene resin (the dataset's basis); no plant size"
  },
  "benchmarks": [
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "expression": "feed:electricity / product:polypropylene",
      "family": "polyolefins",
      "kpi": "pp-specific-electricity",
      "problem": "kWh/kg to kWh/t needs core's foundation.units (pip install 'cheme-as-code[units]')",
      "reference": {
        "basis": "unallocated",
        "conditions": {
          "region": "Western Europe",
          "technology": "PP production, process not named",
          "year": 2009
        },
        "id": "iea-2009-pp-electricity",
        "note": "From the best-practice value (0.9 GJ/t, Table 1) to the estimated current Western European average (1.0 GJ/t, Table 13), both after Schyns (2006), in final energy terms, converted at 3.6 MJ/kWh. The same rows give 0.1 GJ/t (best practice) and 1.0 GJ/t (average) of steam. Independent of the dataset, which takes US plant data.",
        "range": [
          250,
          277.8
        ],
        "source": {
          "accessed": "2026-11-05",
          "citation": "Saygin, D., Patel, M.K., Tam, C., Gielen, D.J. (2009) Chemical and Petrochemical Sector: Potential of best practice technology and other measures for improving energy efficiency. IEA Information Paper, OECD/IEA, Paris",
          "kind": "iea",
          "locator": "Table 1, p. 16, and Table 13, p. 52",
          "url": "https://iea.blob.core.windows.net/assets/c2d071e4-4142-44f1-8a41-88ece29be439/ChemicalandPetrochemicalSector.pdf"
        }
      },
      "status": "unchecked",
      "title": "Electricity per t of polypropylene",
      "unit": "kWh/t",
      "value": null
    },
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "expression": "feed:propylene / product:polypropylene",
      "family": "polyolefins",
      "kpi": "pp-specific-propylene",
      "problem": "1 to kg/t needs core's foundation.units (pip install 'cheme-as-code[units]')",
      "reference": {
        "basis": "unallocated",
        "conditions": {
          "region": "EU",
          "technology": "HDPE plants (24 reporting, average age 15 years, average capacity 161 kt/a)",
          "year": 1999
        },
        "id": "bref-pol-hdpe-monomer-for-pp",
        "note": "HDPE plants, applied to PP by the BREF's own comparison (section 3.3.5, which adds that PP monomer use differs slightly from these HDPE figures with the purity of the propylene). The ends are the average of the top 50 % of plants and the average of the 4th quartile, not single-plant extremes; the European average is 1027 kg/t. Section 3.3.5 pairs gas-phase PP with LLDPE and bulk PP with modern PE gas-phase plants process by process; the LLDPE range (Table 3.13: 1015 to 1043 kg/t) would put the dataset's 1014 kg/t 1 kg/t below its top-50 % average.",
        "range": [
          1008,
          1066
        ],
        "source": {
          "accessed": "2026-11-05",
          "citation": "European Commission JRC (2007) Reference Document on Best Available Techniques in the Production of Polymers, August 2007",
          "kind": "bref",
          "locator": "Section 3.3.3, Table 3.11, p. 64; section 3.3.5, p. 66",
          "url": "https://eippcb.jrc.ec.europa.eu/sites/default/files/2019-11/pol_bref_0807.pdf"
        }
      },
      "status": "unchecked",
      "title": "Propylene consumption per t of polypropylene",
      "unit": "kg/t",
      "value": null
    }
  ],
  "chemistry": {
    "inputs": [
      {
        "chemical": "propylene",
        "grade": null,
        "inventory_key": "feed:propylene",
        "role": "feedstock"
      },
      {
        "chemical": "methane",
        "grade": null,
        "inventory_key": "feed:natural-gas",
        "note": "natural gas burnt for process energy, taken as pure methane (ASSUMED)",
        "role": "feedstock"
      },
      {
        "chemical": "air",
        "grade": null,
        "note": "combustion air, free; its O2 is feed:O2",
        "role": "feedstock"
      }
    ],
    "outputs": [
      {
        "chemical": "polypropylene",
        "grade": null,
        "inventory_key": "product:polypropylene",
        "role": "main-product"
      },
      {
        "chemical": "carbon-dioxide",
        "grade": null,
        "inventory_key": "emission:CO2",
        "role": "emission"
      },
      {
        "chemical": "water",
        "grade": null,
        "inventory_key": "emission:H2O",
        "note": "combustion water vapour",
        "role": "emission"
      }
    ],
    "utilities": [
      {
        "chemical": "electricity",
        "grade": null,
        "inventory_key": "feed:electricity",
        "note": "grid and cogeneration electricity of the source, both supplied as grid (ASSUMED)",
        "role": "utility"
      },
      {
        "chemical": "nitrogen",
        "grade": "gan-8barg-10ppm",
        "inventory_key": "feed:nitrogen",
        "note": "purge and inerting nitrogen, 64 kg/t; the source states no grade, so the gaseous site grade (the Atlas GAN market, not liquid nitrogen) is ASSUMED",
        "role": "utility"
      }
    ]
  },
  "description": "",
  "design_basis": null,
  "engineering": null,
  "facets": {
    "feedstock_basis": [
      "fossil"
    ],
    "product_classes": [
      "polymers"
    ],
    "region": "US",
    "unit_operations": [
      "reaction",
      "compression",
      "extrusion"
    ]
  },
  "families": [
    "polyolefins"
  ],
  "gap_count": 4,
  "gates": null,
  "id": "polypropylene-1",
  "issues": {
    "closed_count": 0,
    "list_url": "https://github.com/ChemE-as-Code/process-library/issues?q=is%3Aissue%20label%3A%22process%3Apolypropylene-1%22",
    "new": {
      "action": "https://github.com/ChemE-as-Code/process-library/issues/new?template=1-action-item.yml&labels=process%3Apolypropylene-1&process=polypropylene-1",
      "change": "https://github.com/ChemE-as-Code/process-library/issues/new?template=4-design-change.yml&labels=process%3Apolypropylene-1&process=polypropylene-1",
      "hold": "https://github.com/ChemE-as-Code/process-library/issues/new?template=2-engineering-hold.yml&labels=process%3Apolypropylene-1&process=polypropylene-1",
      "process": "https://github.com/ChemE-as-Code/process-library/issues/new?template=6-process-development.yml&labels=process%3Apolypropylene-1&process=polypropylene-1",
      "tq": "https://github.com/ChemE-as-Code/process-library/issues/new?template=3-technical-query.yml&labels=process%3Apolypropylene-1&process=polypropylene-1",
      "tracker": "https://github.com/ChemE-as-Code/process-library/issues/new?template=7-process-tracker.yml&labels=process%3Apolypropylene-1&process=polypropylene-1"
    },
    "open": [],
    "open_by_gate": {},
    "open_count": 0,
    "private": false,
    "repository": "ChemE-as-Code/process-library"
  },
  "keywords": [
    "polypropylene",
    "PP",
    "polyolefin",
    "Ziegler-Natta",
    "Spheripol",
    "bulk polymerisation",
    "loop reactor",
    "gas phase",
    "Unipol",
    "propylene"
  ],
  "lca": null,
  "lci_gaps": [
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "key": "feed:propylene",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "key": "output:offgas",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "key": "output:solid-waste-landfill",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "polypropylene-bulk-gas-phase",
      "key": "output:hazardous-waste",
      "link": "technosphere",
      "type": "output"
    }
  ],
  "maintainers": [],
  "maturity": "concept",
  "preliminary": true,
  "provenance": {
    "library_commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174",
    "previews": null,
    "previews_stale": false,
    "source_commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174"
  },
  "publication": {
    "license": "CC-BY-4.0",
    "status": "public"
  },
  "references": [
    {
      "title": "Franklin Associates, a Division of Eastern Research Group (2021) Cradle-to-gate life cycle analysis of polypropylene (PP) resin, final report for the American Chemistry Council Plastics Division, Table 12",
      "url": "https://www.americanchemistry.com/content/download/8063/file/Cradle-to-Gate-Life-Cycle-Analysis-of-Polypropylene-PP-Resin.pdf"
    },
    {
      "title": "European Commission JRC (2007) Reference Document on Best Available Techniques in the Production of Polymers (POL BREF), sections 3.2.5, 3.3.3 and 3.3.5",
      "url": "https://eippcb.jrc.ec.europa.eu/sites/default/files/2019-11/pol_bref_0807.pdf"
    },
    {
      "title": "Prohaska, T. et al. (2022) Standard atomic weights of the elements 2021 (IUPAC Technical Report), Pure Appl. Chem. 94:573"
    },
    {
      "title": "Saygin, D., Patel, M.K., Tam, C., Gielen, D.J. (2009) Chemical and Petrochemical Sector: Potential of best practice technology and other measures for improving energy efficiency. IEA Information Paper, OECD/IEA, Tables 1 and 13 (benchmark reference only)",
      "url": "https://iea.blob.core.windows.net/assets/c2d071e4-4142-44f1-8a41-88ece29be439/ChemicalandPetrochemicalSector.pdf"
    },
    {
      "title": "Plastics Europe (2026) Eco-profile of Polyolefins: High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE), Polypropylene (PP). January 2026, LCA practitioner ifeu Heidelberg, Table 5 (benchmark reference only)",
      "url": "https://plasticseurope.org/wp-content/uploads/2026/03/PE-and-PP.zip"
    }
  ],
  "repository": {
    "access": "public",
    "path": "processes/polypropylene-1",
    "url": "https://github.com/ChemE-as-Code/process-library"
  },
  "representations": [],
  "summary": "Sourced conceptual inventory per tonne of polypropylene resin: the published gate-to-gate data of three US plants (2015-2016, two-thirds bulk loop, one-third gas phase), natural gas combustion by stoichiometry. No flowsheet; not reviewed.",
  "title": "Polypropylene by Ziegler-Natta polymerisation of propylene, bulk loop and gas phase",
  "validation": {
    "status": "unreviewed"
  },
  "viewer": null
}