{
  "authors": [],
  "basis": {
    "capacity": "1000 ADt/d bleached softwood kraft market pulp (ASSUMED normalisation basis)",
    "location": "generic (not chosen)",
    "operating_hours_per_year": 8400
  },
  "benchmarks": [],
  "chemistry": {
    "inputs": [
      {
        "chemical": "wood-chips",
        "grade": null,
        "note": "feed:CHIPS: softwood chips, screened, 50 % moisture, 4.09 kg/kg pulp",
        "role": "feedstock"
      },
      {
        "chemical": "sodium-hydroxide",
        "grade": null,
        "note": "feed:NAOH: sodium hydroxide 50 wt% make-up, counted by mass of the solution",
        "role": "feedstock"
      },
      {
        "chemical": "chlorine-dioxide",
        "grade": null,
        "note": "feed:CLO2: chlorine dioxide water, 10 g ClO2 per kg, generated outside the boundary, counted by mass of the solution",
        "role": "feedstock"
      },
      {
        "chemical": "hydrogen-peroxide",
        "grade": null,
        "note": "feed:H2O2: hydrogen peroxide 50 wt%, counted by mass of the solution",
        "role": "feedstock"
      },
      {
        "chemical": "sulfuric-acid",
        "grade": null,
        "note": "feed:H2SO4: sulfuric acid 93 wt%",
        "role": "feedstock"
      },
      {
        "chemical": "sodium-sulfate",
        "grade": null,
        "note": "feed:SALT: sodium sulfate (saltcake make-up)",
        "role": "feedstock"
      },
      {
        "chemical": "calcium-oxide",
        "grade": null,
        "note": "feed:CAO: purchased burnt lime (Ca make-up)",
        "role": "feedstock"
      },
      {
        "chemical": "oxygen",
        "grade": null,
        "inventory_key": "feed:O2",
        "note": "O2 delignification and EOP stage; asu-1 makes it",
        "role": "feedstock"
      },
      {
        "chemical": "water",
        "grade": null,
        "inventory_key": "feed:FW",
        "note": "Process water to the bleach plant and post-O2 washing",
        "role": "feedstock"
      },
      {
        "chemical": "air",
        "grade": null,
        "inventory_key": "feed:AIR",
        "note": "Recovery boiler and kiln combustion air",
        "role": "feedstock"
      },
      {
        "chemical": "methane",
        "grade": null,
        "inventory_key": "feed:NG",
        "note": "Natural gas (as methane) to the lime kiln",
        "role": "feedstock"
      }
    ],
    "outputs": [
      {
        "chemical": "bleached-kraft-pulp",
        "grade": null,
        "inventory_key": "product:PULP",
        "note": "Bleached softwood kraft market pulp, 90 % dry (bales)",
        "role": "main-product"
      },
      {
        "chemical": "electricity",
        "grade": null,
        "inventory_key": "product:EEXP",
        "note": "Net export, 263 kWh/ADt (D-014)",
        "role": "co-product"
      },
      {
        "chemical": "wastewater",
        "grade": null,
        "inventory_key": "product:WW",
        "note": "Bleach plant effluent, 18 m3/ADt to biological treatment",
        "role": "waste"
      },
      {
        "chemical": "carbon-dioxide",
        "grade": null,
        "inventory_key": "product:STACK",
        "note": "Mostly biogenic (black liquor, lime mud); fossil from kiln natural gas",
        "role": "emission"
      }
    ],
    "utilities": [
      {
        "chemical": "cooling-water",
        "grade": null,
        "inventory_key": "product:CW",
        "note": "25/35 C (ASSUMED)",
        "role": "utility"
      }
    ]
  },
  "description": "Chips are cooked with white liquor (NaOH and Na2S) in a continuous digester; the brown stock\nis washed counter-currently with the O2-stage filtrate, delignified with oxygen, bleached in\na D0-EOP-D1 sequence (outline) and dried to 90 % dry market pulp. The weak black liquor is\nevaporated to 80 % solids and burnt in the recovery boiler: the organics raise HP steam for\nan extraction back-pressure turbine with a condensing tail, and the smelt (Na2CO3, Na2S) is\ndissolved to green liquor, causticized with lime to white liquor and returned to the\ndigester. The lime mud is reburned in a natural gas fired kiln. Sodium and sulfur losses\nare made up with NaOH and saltcake, calcium losses with purchased lime.\n\nAll flows are concept estimates of an independent balance (scripts/kraft_balance.py) on\nlumped model components for wood and black liquor, with sourced ranges (JRC pulp and paper\nBREF 2015, Tran and Vakkilainen) and assumed design parameters. No wood, black liquor or\nelectrolyte thermodynamics is calculated. See DESIGN.md for every assumption and gated step.\n",
  "design_basis": {
    "assumptions": [
      "ASSUMED wood: 41/28/27/3.5/0.5 % cellulose/hemicellulose/lignin/extractives/ash, 50 % moisture (D-003).",
      "ASSUMED yields on dry wood: 47.0 % after cooking (kappa ~28), 45.6 % after O2 (kappa ~15), 44.0 % bleached (D-004).",
      "ASSUMED washing: 3 % of dissolved solids carried out of brown stock washing, 6 % out of post-O2 washing; wash presses discharge at 25 % consistency (D-006).",
      "ASSUMED black liquor 15 % solids weak, 80 % strong; evaporator economy 6.0 (D-007).",
      "ASSUMED recovery boiler: air ratio 1.15; 3.5 kg steam per kg BLDS (Tran and Vakkilainen); SO2 0.1 kg S, NOx 1.2 kg, dust 0.3 kg per ADt inside BREF Table 3.13 (D-010).",
      "ASSUMED recausticizing and kiln: grits 5, mud purge 10 kg/ADt; calcination 0.95; mud 80 % solids; kiln 1.5 GJ/ADt natural gas (D-009).",
      "ASSUMED heat and power by consumer (D-011): 11.6 GJ/ADt process heat and 650 kWh/ADt, inside BREF 2015 sec. 3.2.2.3 ranges.",
      "No wood or electrolyte thermodynamics: wood, liquors and smelt are lumped model components (materials.yaml, D-007)."
    ],
    "source": "process/design-basis.yaml"
  },
  "engineering": {
    "description": "Bleached softwood kraft market pulp mill (1000 ADt/d) with chemical recovery; concept BFD/PFD and preliminary gate-to-gate LCI (process-library#180)",
    "name": "Kraft pulp and chemical recovery",
    "requires": "cheme-as-code>=0.8",
    "stage": "concept",
    "stages": [
      {
        "id": "concept",
        "title": "Concept and feasibility"
      },
      {
        "id": "basic",
        "title": "Basic engineering"
      },
      {
        "id": "detail",
        "title": "Detail engineering"
      }
    ],
    "tool": "plantcode"
  },
  "facets": {
    "feedstock_basis": [
      "biogenic"
    ],
    "product_classes": [
      "materials"
    ],
    "region": "generic",
    "unit_operations": [
      "reaction",
      "washing",
      "evaporation",
      "combustion",
      "calcination",
      "filtration",
      "drying",
      "power-generation"
    ]
  },
  "families": [
    "bio-based-chemicals"
  ],
  "gap_count": 4,
  "gates": null,
  "id": "kraft-pulp-1",
  "issues": {
    "closed_count": 0,
    "list_url": "https://github.com/ChemE-as-Code/process-library/issues?q=is%3Aissue%20label%3A%22process%3Akraft-pulp-1%22",
    "new": {
      "action": "https://github.com/ChemE-as-Code/process-library/issues/new?template=1-action-item.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1",
      "change": "https://github.com/ChemE-as-Code/process-library/issues/new?template=4-design-change.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1",
      "hold": "https://github.com/ChemE-as-Code/process-library/issues/new?template=2-engineering-hold.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1",
      "process": "https://github.com/ChemE-as-Code/process-library/issues/new?template=6-process-development.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1",
      "tq": "https://github.com/ChemE-as-Code/process-library/issues/new?template=3-technical-query.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1",
      "tracker": "https://github.com/ChemE-as-Code/process-library/issues/new?template=7-process-tracker.yml&labels=process%3Akraft-pulp-1&process=kraft-pulp-1"
    },
    "open": [],
    "open_by_gate": {},
    "open_count": 0,
    "private": false,
    "repository": "ChemE-as-Code/process-library"
  },
  "keywords": [
    "kraft pulp",
    "bleached softwood kraft",
    "market pulp",
    "chemical pulping",
    "continuous digester",
    "oxygen delignification",
    "ECF bleaching",
    "black liquor",
    "recovery boiler",
    "causticizing",
    "lime kiln",
    "biogenic CO2"
  ],
  "lca": {
    "allocation": "shares",
    "backend": "factors",
    "boundary": "cradle-to-gate",
    "categories": [
      {
        "id": "climate-change",
        "method": "GWP100",
        "title": "Climate change",
        "unit": "kg CO2-eq"
      }
    ],
    "data_sources": [],
    "factors_status": "published",
    "functional_unit": {
      "amount": 1,
      "chemical": "bleached-kraft-pulp",
      "grade": null,
      "label": "1 kg bleached kraft pulp",
      "product": "PULP",
      "product_name": "Bleached kraft pulp",
      "product_title": "Bleached softwood kraft market pulp, 90 % dry (bales)",
      "unit": "kg"
    },
    "goal": "Preliminary foreground (gate-to-gate) life cycle inventory of bleached softwood kraft market pulp at the concept stage: which wood, chemicals, utilities, emissions (biogenic and fossil CO2 apart) and wastes the balanced flowsheet implies per kg of air-dry pulp, ready to be linked to background datasets later. Flows are concept estimates on sourced ranges and assumed design parameters (DESIGN.md D-003 to D-011).",
    "inventory": [
      {
        "direction": "input",
        "key": "feed:CHIPS",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 4.0909,
        "title": "Softwood chips, screened (50 % moisture)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:NAOH",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0418848,
        "title": "Sodium hydroxide 50 wt% (make-up to the O2 stage, bleaching alkali)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:O2",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0260016,
        "title": "Oxygen (O2 delignification and EOP stage)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:CLO2",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.0,
        "title": "Chlorine dioxide water, 10 g/kg (generated outside the boundary)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:H2O2",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.006,
        "title": "Hydrogen peroxide 50 wt%",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:H2SO4",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0043008,
        "title": "Sulfuric acid 93 wt%",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:SALT",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.003276,
        "title": "Sodium sulfate (saltcake make-up)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:CAO",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00839279,
        "title": "Purchased burnt lime (Ca make-up)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:NG",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.03,
        "title": "Natural gas (lime kiln fuel)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:AIR",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 9.85925,
        "title": "Combustion air",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:FW",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 16.4167,
        "title": "Process water (fresh, treated)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:PULP",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.0,
        "title": "Bleached softwood kraft market pulp, 90 % dry (bales)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:EEXP",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.262675,
        "title": "Electricity export to the grid (turbine generation less mill use)",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:WW",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 18.0,
        "title": "Bleach plant effluent to the biological treatment plant",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:STACK",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 11.5361,
        "title": "Flue gases (recovery boiler after ESP, lime kiln) to stack",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:VENT",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.912743,
        "title": "Vents to atmosphere (O2 stage, bleach plant, pulp dryer exhaust)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:SW",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0378888,
        "title": "Solid wastes to landfill (dregs, grits, lime mud purge)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:CW",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.26623,
        "title": "Cooling water return",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "emission:CO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0822958,
        "title": "CO2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:CO2B",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 2.30458,
        "title": "CO2B to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:H2O",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 2.16604,
        "title": "H2O to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:N2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 7.57733,
        "title": "N2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:NO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00160492,
        "title": "NO2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:Na2SO4",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.000298553,
        "title": "Na2SO4 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:O2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.316524,
        "title": "O2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00020259,
        "title": "SO2 to the environment",
        "unit": "kg"
      }
    ],
    "not_computed": [],
    "publishable": false,
    "result": {
      "classification": "partial",
      "gaps": 13,
      "label": "partial screening carbon footprint",
      "publication": "public"
    },
    "sources": [
      "lca/README.md",
      "lca/dataset.yaml",
      "lca/factors.yaml",
      "lca/gaps.csv",
      "lca/inventory.csv",
      "lca/lca.yaml",
      "lca/mappings.yaml",
      "lca/results.csv",
      "lca/results.md",
      "lca/uncertainty.csv"
    ],
    "values_withheld": "stale-run-manifest",
    "withheld_reason": "stale-run-manifest"
  },
  "lci_gaps": [
    {
      "dataset": "bleached-softwood-kraft-pulp-with-chemical-recovery-1000-adt-d-market-pulp",
      "key": "feed:CHIPS",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "bleached-softwood-kraft-pulp-with-chemical-recovery-1000-adt-d-market-pulp",
      "key": "feed:CLO2",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "bleached-softwood-kraft-pulp-with-chemical-recovery-1000-adt-d-market-pulp",
      "key": "feed:SALT",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "bleached-softwood-kraft-pulp-with-chemical-recovery-1000-adt-d-market-pulp",
      "key": "feed:CAO",
      "link": "technosphere",
      "type": "input"
    }
  ],
  "maintainers": [
    {
      "name": "Artur Schweidtmann"
    }
  ],
  "maturity": "concept",
  "preliminary": true,
  "provenance": {
    "library_commit": "c3ab3488c602bc797fdc98feffd4578375150dd0",
    "previews": {
      "sheets": [
        "BFD",
        "PFD"
      ],
      "source_commit": "c3ab3488c602bc797fdc98feffd4578375150dd0",
      "tool": "cheme 1.6.0 (pyDEXPI 2.1.0)"
    },
    "previews_stale": false,
    "source_commit": "c3ab3488c602bc797fdc98feffd4578375150dd0"
  },
  "publication": {
    "license": "CC-BY-4.0",
    "status": "public"
  },
  "references": [
    {
      "doi": "10.2791/370629",
      "title": "Suhr, M. et al. (2015) Best Available Techniques (BAT) Reference Document for the Production of Pulp, Paper and Board. JRC Science and Policy Report EUR 27235 EN, chapter 3 (kraft): sec. 3.2.2.2-3.2.2.3, Tables 3.3, 3.5, 3.12, 3.13, 3.17, sec. 3.2.2.6.2, sec. 3.3.8"
    },
    {
      "title": "Tran, H. and Vakkilainen, E. K. (2007) Advances in the kraft chemical recovery process. 3rd ICEP International Colloquium on Eucalyptus Pulp, Belo Horizonte (recovery ~97 %, reduction > 90 %, causticizing 80-83 %, black liquor 13-15 MJ/kg, steam ~3.5 kg/kg solids, 84 bar 480 C unit)",
      "url": "https://www.eucalyptus.com.br/icep03/200Tran.text.pdf.pdf"
    },
    {
      "title": "US EPA (1990, reformatted 1995) AP-42 Fifth Edition, Volume I, Section 10.2 Chemical Wood Pulping (process description; NOx order of magnitude from kilns and recovery furnaces)",
      "url": "https://www.epa.gov/sites/default/files/2020-10/documents/c10s02.pdf"
    },
    {
      "doi": "10.1002/14356007.a18_545.pub4",
      "title": "Ullmann's Encyclopedia of Industrial Chemistry: Pulp (route reference lead from issue #180; not audited in this run)"
    },
    {
      "title": "Wagman, D. D. et al. (1982) The NBS tables of chemical thermodynamic properties. J. Phys. Chem. Ref. Data 11, Suppl. 2 (formation enthalpies of the inorganic reactions; values to be checked)"
    }
  ],
  "repository": {
    "access": "public",
    "path": "processes/kraft-pulp-1",
    "url": "https://github.com/ChemE-as-Code/process-library"
  },
  "representations": [
    {
      "bytes": 76188,
      "id": "BFD",
      "kind": "bfd",
      "preview": "artifacts/kraft-pulp-1/BFD.svg",
      "source": "process/BFD.xml",
      "status": "preview",
      "title": "Block flow diagram"
    },
    {
      "bytes": 313470,
      "id": "PFD",
      "kind": "pfd",
      "preview": "artifacts/kraft-pulp-1/PFD.svg",
      "source": "process/PFD.xml",
      "status": "preview",
      "title": "Process flow diagram"
    },
    {
      "id": "process-model",
      "kind": "process-model",
      "source": "process/flowsheet.yaml",
      "status": "viewer",
      "title": "Flowsheet and stream table"
    },
    {
      "id": "equipment-list",
      "kind": "equipment-list",
      "source": "equipment/equipment-list.yaml",
      "status": "viewer",
      "title": "Equipment list"
    },
    {
      "id": "lca",
      "kind": "lca",
      "source": "lca/lca.yaml",
      "status": "viewer",
      "title": "Life cycle assessment"
    }
  ],
  "summary": "Softwood chips to bleached kraft market pulp: continuous digester, brown stock washing, O2 delignification, ECF bleaching outline, drying machine, black liquor evaporation, recovery boiler, recausticizing and lime kiln, with the turbine generator; biogenic and fossil CO2 kept apart. Concept stage, assumed basis.",
  "title": "Bleached softwood kraft pulp with chemical recovery (1000 ADt/d market pulp, concept)",
  "validation": {
    "notes": "Concept BFD/PFD with closed mass, component and element balances (cheme validate, cheme process streams: 10 blocks, 17 steps, reactive steps balanced by extents of lumped bookkeeping reactions). Flows and compositions are specified values of an independent balance (scripts/kraft_balance.py) whose element residuals are below 1e-6 kmol/h. Wood and black liquor are lumped model components (not molecular identities), no electrolyte speciation and no property package covers the streams, so the energy balance is not evaluable in core: duties are sourced specific consumptions split by consumer (ASSUMED). Calculation maturity: none (`cheme maturity`), because no feed flow or composition is `given` with a source: every value is an ASSUMED design parameter or a sourced range, and `concept` is the lowest level the manifest allows. The gate-to-gate LCI is preliminary, every background unmapped. Per kg pulp: fossil CO2 0.0823 kg (kiln natural gas), biogenic CO2 2.30 kg. The climate result keeps each CO2 flow's declared origin (trace_emissions false). The PCF line \"fossil carbon content of the product\" (0.0084 kg C) is a core limitation; the pulp's carbon is all biogenic (lca/README.md, DESIGN.md D-012). Independent agent review 2026-10-28 (reviews/), findings answered in PROGRESS.md.",
    "status": "unreviewed"
  },
  "viewer": {
    "commit": "c3ab3488c602bc797fdc98feffd4578375150dd0",
    "dirty": false,
    "sheets": [
      "process/BFD.xml",
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