{
  "authors": [],
  "basis": {
    "capacity": "1000 t/d H2SO4 as 98.5 wt% acid (ASSUMED)",
    "location": "generic (not chosen)",
    "operating_hours_per_year": 8000
  },
  "benchmarks": [],
  "chemistry": {
    "inputs": [
      {
        "chemical": "sulfur",
        "grade": null,
        "note": "feed:SULFUR: molten sulfur, 0.323 kg/kg acid",
        "role": "feedstock"
      },
      {
        "chemical": "air",
        "grade": null,
        "inventory_key": "feed:AIR",
        "note": "Combustion and oxidation oxygen",
        "role": "feedstock"
      },
      {
        "chemical": "water",
        "grade": null,
        "inventory_key": "feed:PW",
        "note": "Dilution water to the acid pump tank (0.166 kg/kg acid)",
        "role": "feedstock"
      }
    ],
    "outputs": [
      {
        "chemical": "sulfuric-acid",
        "grade": null,
        "inventory_key": "product:ACID",
        "note": "Sulfuric acid 98.5 wt% to storage, counted by mass of the acid",
        "role": "main-product"
      },
      {
        "chemical": "nitrogen",
        "grade": null,
        "inventory_key": "product:STACK",
        "note": "Tail gas, mostly N2 with 4.5 mol% O2, 0.04 mol% SO2 (1.94 g SO2/kg acid) and SO3/acid mist",
        "role": "emission"
      }
    ],
    "utilities": [
      {
        "chemical": "electricity",
        "grade": null,
        "inventory_key": "feed:POWER",
        "note": "Main air blower and acid pump (ASSUMED electric drives), 0.055 kWh/kg acid",
        "role": "utility"
      },
      {
        "chemical": "steam",
        "grade": null,
        "inventory_key": "product:HPS",
        "note": "HP steam 4100 kPa(a), 673 K, 1.34 kg/kg acid (1.03 kWh/kg above boiler feed water)",
        "role": "co-product"
      },
      {
        "chemical": "cooling-water",
        "grade": null,
        "inventory_key": "product:CW",
        "note": "Acid and product coolers, 0.49 kWh/kg acid, 298/308 K (ASSUMED)",
        "role": "utility"
      }
    ]
  },
  "description": "Air is dried in a tower irrigated with 98.5 wt% acid and blown into the sulfur furnace, which\nburns molten sulfur to an 11.5 mol% SO2 gas. A waste heat boiler cools the gas to the first\nbed. Four adiabatic V2O5 beds convert the SO2 (63 / 87 / 95 % after beds 1-3, 99.7 % overall,\nconversion model within the ranges of Speight 2002); the gas is cooled between the beds by a\ngas/gas exchanger, a superheater and economisers, absorbed in an intermediate tower after\nbed 3, reheated, converted in bed 4 and absorbed in a final tower before the stack. One acid\nheader serves the three towers; dilution water is added in the pump tank and the product is\ndrawn after the acid cooler.\n\nAll values are concept estimates from an independent balance script; core can check the mass,\nelement and reaction balances and the equilibrium distance of the beds, but has no property\npackage for SO2/SO3 gas or aqueous acid to close the energy balance itself (DESIGN.md D-006).\n",
  "design_basis": {
    "assumptions": [
      "ASSUMED burner gas 11.5 mol% SO2 in dry air (D-004): sets the air flow.",
      "Converter 3+1 with intermediate absorption after bed 3; cumulative SO2 conversion 63 / 87 / 95 % after beds 1-3 and 99.7 % overall, within the ranges of the tech-heavy-chem-sulfuric-acid skill (Speight 2002); a conversion model, not kinetics (D-005).",
      "ASSUMED bed inlet temperatures 693 / 713 / 708 / 683 K; beds adiabatic, no heat losses (D-005).",
      "ASSUMED SO3 absorption 99.9 % in each absorption tower (D-007).",
      "ASSUMED one common acid header at 343 K for the drying, intermediate and final towers; acid outlet temperatures 338 / 383 / 363 K (D-007).",
      "ASSUMED main blower isentropic efficiency 0.80, motor efficiency 0.96; acid pump head 35 m, efficiency 0.70 (D-010).",
      "All flows, temperatures and duties are concept estimates (scripts/balance.py, D-006); accuracy +/-20 % not demonstrated."
    ],
    "source": "process/design-basis.yaml"
  },
  "engineering": {
    "description": "",
    "name": "Sulfuric acid (sulfur burning, double contact)",
    "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": [
      "mineral"
    ],
    "product_classes": [
      "chemicals"
    ],
    "region": "generic",
    "unit_operations": [
      "combustion",
      "reaction",
      "absorption",
      "heat-exchange",
      "compression"
    ]
  },
  "families": [
    "sulfuric-acid"
  ],
  "gap_count": 0,
  "gates": null,
  "id": "sulfuric-acid-1",
  "issues": {
    "closed_count": 0,
    "list_url": "https://github.com/ChemE-as-Code/process-library/issues?q=is%3Aissue%20label%3A%22process%3Asulfuric-acid-1%22",
    "new": {
      "action": "https://github.com/ChemE-as-Code/process-library/issues/new?template=1-action-item.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1",
      "change": "https://github.com/ChemE-as-Code/process-library/issues/new?template=4-design-change.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1",
      "hold": "https://github.com/ChemE-as-Code/process-library/issues/new?template=2-engineering-hold.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1",
      "process": "https://github.com/ChemE-as-Code/process-library/issues/new?template=6-process-development.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1",
      "tq": "https://github.com/ChemE-as-Code/process-library/issues/new?template=3-technical-query.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1",
      "tracker": "https://github.com/ChemE-as-Code/process-library/issues/new?template=7-process-tracker.yml&labels=process%3Asulfuric-acid-1&process=sulfuric-acid-1"
    },
    "open": [],
    "open_by_gate": {},
    "open_count": 0,
    "private": false,
    "repository": "ChemE-as-Code/process-library"
  },
  "keywords": [
    "sulfuric acid",
    "contact process",
    "double absorption",
    "DCDA",
    "sulfur burning",
    "SO2 oxidation",
    "vanadium pentoxide",
    "waste heat boiler",
    "steam export",
    "SO2 emissions"
  ],
  "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": "none",
    "functional_unit": {
      "amount": 1,
      "chemical": "sulfuric-acid",
      "grade": null,
      "label": "1 kg sulfuric acid",
      "product": "ACID",
      "product_name": "Sulfuric acid",
      "product_title": "Sulfuric acid 98.5 wt% to storage",
      "unit": "kg"
    },
    "goal": "Preliminary gate-to-gate life cycle inventory of 98.5 wt% sulfuric acid from a sulfur-burning double-contact plant at the concept stage: which raw materials, utilities, co-products and emissions the plant exchanges per kg of acid, as the foreground for a later cradle-to-gate study. No impact results: the backgrounds are not mapped yet (D-013).",
    "inventory": [
      {
        "direction": "input",
        "key": "feed:SULFUR",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.323015,
        "title": "Molten sulfur",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:AIR",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 2.56694,
        "title": "Atmospheric air",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:PW",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.165737,
        "title": "Process (dilution) water",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:POWER",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0545376,
        "title": "Electric power",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:ACID",
        "kind": "material",
        "phase": "operation",
        "provenance": "calculated",
        "quantity": 1.0,
        "title": "Sulfuric acid 98.5 wt% to storage",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:STACK",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 2.05568,
        "title": "Tail gas to stack",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:HPS",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.03097,
        "title": "HP steam export 4100 kPa(a), 673 K (heat above boiler feed water)",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:CW",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.491403,
        "title": "Cooling water return",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "emission:AR",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.032544,
        "title": "AR to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:H2O",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0,
        "title": "H2O to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:N2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.91697,
        "title": "N2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:O2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.104196,
        "title": "O2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:S",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0,
        "title": "S to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00193609,
        "title": "SO2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SO3",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 3.86733e-05,
        "title": "SO3 to the environment",
        "unit": "kg"
      }
    ],
    "not_computed": [],
    "publishable": false,
    "result": {
      "classification": "partial",
      "gaps": 4,
      "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"
    ],
    "values_withheld": "stale-run-manifest",
    "withheld_reason": "stale-run-manifest"
  },
  "lci_gaps": [],
  "maintainers": [
    {
      "name": "Artur Schweidtmann"
    }
  ],
  "maturity": "concept",
  "preliminary": false,
  "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": "10.1002/14356007.a25_635",
      "title": "Müller, H. Sulfuric Acid and Sulfur Trioxide. Ullmann's Encyclopedia of Industrial Chemistry"
    },
    {
      "title": "Speight, J. G. (2002) Chemical Process and Design Handbook, McGraw-Hill, Part 2: sulfuric acid"
    },
    {
      "title": "European Commission JRC (2007) Reference Document on BAT for the Manufacture of Large Volume Inorganic Chemicals - Ammonia, Acids and Fertilisers",
      "url": "https://eippcb.jrc.ec.europa.eu/reference/large-volume-inorganic-chemicals-ammonia-acids-and-fertilisers"
    },
    {
      "title": "Wagman, D. D. et al. (1982) The NBS tables of chemical thermodynamic properties. J. Phys. Chem. Ref. Data 11, Suppl. 2"
    }
  ],
  "repository": {
    "access": "public",
    "path": "processes/sulfuric-acid-1",
    "url": "https://github.com/ChemE-as-Code/process-library"
  },
  "representations": [
    {
      "bytes": 29500,
      "id": "BFD",
      "kind": "bfd",
      "preview": "artifacts/sulfuric-acid-1/BFD.svg",
      "source": "process/BFD.xml",
      "status": "preview",
      "title": "Block flow diagram"
    },
    {
      "bytes": 181293,
      "id": "PFD",
      "kind": "pfd",
      "preview": "artifacts/sulfuric-acid-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": "simulation",
      "kind": "simulation",
      "source": "process/simulation.yaml",
      "status": "viewer",
      "title": "Process simulation"
    },
    {
      "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": "Molten sulfur burned in dried air, SO2 oxidised over four V2O5 beds (3+1) with intermediate and final absorption to 98.5 wt% acid; waste heat recovered as exported HP steam. Concept stage, assumed basis, with a preliminary gate-to-gate LCI.",
  "title": "Sulfuric acid from sulfur burning, double contact / double absorption (1000 t/d, 98.5 wt%)",
  "validation": {
    "notes": "Concept PFD with closed mass, component, element and reaction-extent balances (cheme validate, cheme process streams); every bed is short of its ideal-gas equilibrium (cheme process reactors). cheme maturity reaches no level: capacity and feeds are assumed, the bed conversions are values within published ranges rather than a sourced design point, and the tower outlets, temperatures and duties come from an independent script (scripts/balance.py) whose energy balance core cannot check (no property package for SO2/SO3 or aqueous acid: core's property-package qualification and electrolyte support). Not reviewed. Main products and feeds are listed under chemistry with their chemicals registry entries (issue #251).",
    "status": "unreviewed"
  },
  "viewer": {
    "commit": "c3ab3488c602bc797fdc98feffd4578375150dd0",
    "dirty": false,
    "sheets": [
      "process/BFD.xml",
      "process/PFD.xml"
    ],
    "skipped": [],
    "snapshot": "snapshots/sulfuric-acid-1/",
    "stale": false,
    "tool": "cheme-as-code 1.6.0",
    "views": [
      "checks",
      "streams"
    ]
  }
}