{
  "authors": [],
  "basis": {
    "capacity": "5000 kg/h crushed crude crystalline SiC, 40 kt/a (ASSUMED normalisation basis)",
    "location": "generic (not chosen)",
    "operating_hours_per_year": 8000
  },
  "benchmarks": [],
  "chemistry": {
    "inputs": [
      {
        "chemical": "silicon-dioxide",
        "grade": null,
        "note": "feed:SAND: silica sand, 1.95 kg/kg crude SiC (unallocated)",
        "role": "feedstock"
      },
      {
        "chemical": "petroleum-coke",
        "grade": null,
        "note": "feed:COKE: green petroleum coke, 1.36 kg/kg crude SiC (unallocated)",
        "role": "feedstock"
      },
      {
        "chemical": "air",
        "grade": null,
        "inventory_key": "feed:AIR",
        "note": "Air drawn over the furnace for the gas burn-off",
        "role": "feedstock"
      }
    ],
    "outputs": [
      {
        "chemical": "silicon-carbide",
        "grade": null,
        "inventory_key": "product:SIC",
        "note": "Crushed crude crystalline SiC, 98 wt%",
        "role": "main-product"
      },
      {
        "chemical": "silicon-carbide",
        "grade": null,
        "inventory_key": "product:MET",
        "note": "Metallurgical-grade SiC, 88 wt%",
        "role": "co-product"
      },
      {
        "chemical": "carbon-dioxide",
        "grade": null,
        "inventory_key": "product:VENT",
        "note": "Burnt furnace gas (fossil carbon of the coke), about 2.1 kg/kg crude SiC unallocated; with CO, CH4, SO2 and silica fume",
        "role": "emission"
      }
    ],
    "utilities": [
      {
        "chemical": "electricity",
        "grade": null,
        "inventory_key": "feed:POWER",
        "note": "Furnace transformers 7.5 kWh/kg crude SiC plus auxiliaries and crushing",
        "role": "utility"
      },
      {
        "chemical": "cooling-water",
        "grade": null,
        "inventory_key": "product:CW",
        "note": "Transformer and bus-bar cooling, 25/35 C (ASSUMED)",
        "role": "utility"
      }
    ]
  },
  "description": "Silica sand and green petroleum coke are mixed with the unreacted mix of earlier runs and\npiled around a graphite core in batch Acheson furnaces. Electric resistance heating drives\nSiO2 + 3 C -> SiC + 2 CO; the CO, the coke volatiles, the sulfur and escaping SiO burn partly\nwith air over the charge and leave through the hood stack. After cooling, the ingot is broken\nand sorted into crude crystalline SiC, a metallurgical-grade fraction and unreacted mix, which\nis recycled with a small purge; the crude SiC is crushed and screened.\n\nAll values are concept estimates from an independent sequential balance with assumed yields,\ngrades and splits, cross-checked against the IPCC/EPA emission factors for silicon carbide.\nThe furnace electricity is a labelled specific-energy basis (7.5 kWh/kg crude SiC, inside\nthe published range for European plants), because cheme process furnace does not cover\ncarbothermal SiC. See DESIGN.md for every assumption and gated step.\n",
  "design_basis": {
    "assumptions": [
      "ASSUMED furnace electricity 7.5 kWh per kg crude SiC (crystalline + metallurgical), inside the 6.3-9.02 kWh/kg reported for European plants (Mehrwald 1992, cited by Lima and Tenorio 2011) and near 7.15 kWh/kg (Fraunhofer IKTS 2023): a labelled specific-energy basis, since cheme process furnace refuses carbothermal SiC (D-004).",
      "ASSUMED product slate: 0.25 kg metallurgical-grade SiC per kg crude crystalline SiC; recycled unreacted mix 3.0 kg/kg; 5 % of the sorted mix purged (D-006).",
      "ASSUMED SiO loss 0.005 kmol per kmol SiC formed; CO burnt at the surface 70 %; CH4 slip at the IPCC Tier 1 default 11.6 kg/t SiC; all coke sulfur to SO2 (D-006).",
      "ASSUMED auxiliary power 0.15 kWh/kg and crushing 0.10 kWh/kg; transformer and bus-bar losses 2 % of the furnace power to cooling water (D-008).",
      "No furnace heat transfer or kinetics model: yields are imposed (D-007). No property package covers the solids or the hot furnace gas (D-007)."
    ],
    "source": "process/design-basis.yaml"
  },
  "engineering": {
    "description": "",
    "name": "Silicon carbide (Acheson process)",
    "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",
      "fossil",
      "electricity"
    ],
    "product_classes": [
      "materials",
      "chemicals"
    ],
    "region": "generic",
    "unit_operations": [
      "reaction",
      "comminution",
      "separation"
    ]
  },
  "families": [
    "inorganic-chemicals"
  ],
  "gap_count": 4,
  "gates": null,
  "id": "silicon-carbide-1",
  "issues": {
    "closed_count": 0,
    "list_url": "https://github.com/ChemE-as-Code/process-library/issues?q=is%3Aissue%20label%3A%22process%3Asilicon-carbide-1%22",
    "new": {
      "action": "https://github.com/ChemE-as-Code/process-library/issues/new?template=1-action-item.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1",
      "change": "https://github.com/ChemE-as-Code/process-library/issues/new?template=4-design-change.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1",
      "hold": "https://github.com/ChemE-as-Code/process-library/issues/new?template=2-engineering-hold.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1",
      "process": "https://github.com/ChemE-as-Code/process-library/issues/new?template=6-process-development.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1",
      "tq": "https://github.com/ChemE-as-Code/process-library/issues/new?template=3-technical-query.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1",
      "tracker": "https://github.com/ChemE-as-Code/process-library/issues/new?template=7-process-tracker.yml&labels=process%3Asilicon-carbide-1&process=silicon-carbide-1"
    },
    "open": [],
    "open_by_gate": {},
    "open_count": 0,
    "private": false,
    "repository": "ChemE-as-Code/process-library"
  },
  "keywords": [
    "silicon carbide",
    "SiC",
    "Acheson process",
    "carborundum",
    "carbothermal reduction",
    "electric resistance furnace",
    "petroleum coke",
    "silica sand",
    "abrasives",
    "refractories",
    "metallurgical SiC"
  ],
  "lca": {
    "allocation": "shares",
    "backend": "factors",
    "boundary": "cradle-to-gate",
    "categories": [
      {
        "id": "climate-change",
        "method": "GWP100",
        "title": "Climate change",
        "unit": "kg CO2-eq"
      }
    ],
    "contributions": [
      {
        "basis": "ipcc2021-gwp100 (124-38-9, air, fossil)",
        "category": "climate-change",
        "impact": 1.6951,
        "key": "emission:CO2",
        "phase": "operation",
        "share": 0.8356,
        "status": "PUBLISHED"
      },
      {
        "basis": "ipcc2021-gwp100 (74-82-8, air, fossil)",
        "category": "climate-change",
        "impact": 0.333572,
        "key": "emission:CH4",
        "phase": "operation",
        "share": 0.1644,
        "status": "PUBLISHED"
      }
    ],
    "data_sources": [],
    "factors_status": "published",
    "functional_unit": {
      "amount": 1,
      "chemical": "silicon-carbide",
      "grade": null,
      "label": "1 kg silicon carbide",
      "product": "SIC",
      "product_name": "Silicon carbide",
      "product_title": "Crushed crude crystalline SiC (98 wt%)",
      "unit": "kg"
    },
    "goal": "Preliminary foreground (gate-to-gate) life cycle inventory of crude crystalline silicon carbide by the Acheson process at the concept stage: which raw materials, electricity, emissions and wastes the balanced flowsheet implies per kg of product, ready to be linked to background datasets later. Flows are concept estimates on assumed yields and a specific-energy furnace basis (DESIGN.md D-004, D-006). The climate value this study reports is the DIRECT (scope 1) furnace CO2 and CH4 only, NOT a carbon footprint: electricity (about 7.7 kWh per kg after allocation, the largest exchange), coke, sand, cooling water and landfill are gaps, and the uncertainty interval covers only the direct amounts. Fossil CO is not characterised by the method; counted by its atmospheric oxidation to CO2 (44/28 kg CO2 per kg CO) it would add about 0.64 kg CO2-eq per kg (D-010).",
    "inventory": [
      {
        "direction": "input",
        "key": "feed:SAND",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.56298,
        "title": "Silica sand",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:COKE",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.08878,
        "title": "Petroleum coke (green)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:AIR",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 7.41538,
        "title": "Air drawn over the furnace surface",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:POWER",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 7.7,
        "title": "Electric power",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:SIC",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.0,
        "title": "Crushed crude crystalline SiC (98 wt%)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:MET",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.25,
        "title": "Metallurgical-grade SiC (88 wt%)",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:WASTE",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.12632,
        "title": "Purged furnace mix to landfill",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:VENT",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 8.94066,
        "title": "Furnace flue gas to atmosphere",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:DUST",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00016,
        "title": "Crusher bag-filter exhaust to atmosphere",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:CW",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.15,
        "title": "Cooling water return",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:AMB",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 5.24462,
        "title": "Heat to ambient air (natural cooling of the ingot, burn-off heat; no fans)",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "emission:CH4",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0111937,
        "title": "CH4 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:CO",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.405575,
        "title": "CO to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:CO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.6951,
        "title": "CO2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:H2O",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.235095,
        "title": "H2O to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:N2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 5.69227,
        "title": "N2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:O2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.861557,
        "title": "O2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0326334,
        "title": "SO2 to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SiC",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00016,
        "title": "SiC to the environment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "emission:SiO2",
        "kind": "emission",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.00723299,
        "title": "SiO2 to the environment",
        "unit": "kg"
      }
    ],
    "no_total": {},
    "not_computed": [],
    "pcf": [],
    "publishable": true,
    "result": {
      "classification": "partial",
      "gaps": 5,
      "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"
    ],
    "totals": {
      "baseline": {
        "climate-change": 2.02868
      }
    },
    "withheld_reason": null
  },
  "lci_gaps": [
    {
      "dataset": "silicon-carbide-by-the-acheson-process-5000-kg-h-crude-sic-concept",
      "key": "feed:SAND",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "silicon-carbide-by-the-acheson-process-5000-kg-h-crude-sic-concept",
      "key": "feed:COKE",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "silicon-carbide-by-the-acheson-process-5000-kg-h-crude-sic-concept",
      "key": "emission:SiC",
      "link": "biosphere",
      "type": "emission"
    },
    {
      "dataset": "silicon-carbide-by-the-acheson-process-5000-kg-h-crude-sic-concept",
      "key": "emission:SiO2",
      "link": "biosphere",
      "type": "emission"
    }
  ],
  "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": [
    {
      "title": "Lima, T. C. F.; Tenorio, J. A. S. (2011) Utilizacao de materia-prima aglomerada na producao de carbureto de silicio em escala-piloto. Rem: Revista Escola de Minas 64(3), 341-345 (pilot Acheson furnace; European specific energy range quoted from Mehrwald 1992)",
      "url": "http://www.redalyc.org/articulo.oa?id=56419948013"
    },
    {
      "title": "U.S. EPA (2009) Technical Support Document for the Silicon Carbide Production Sector: Proposed Rule for Mandatory Reporting of Greenhouse Gases (carbon retained in SiC; IPCC 2006 Tier 1 factors, Table 4)",
      "url": "https://19january2021snapshot.epa.gov/sites/static/files/2015-03/documents/subpartbb-tsd-siliconcarbide.pdf"
    },
    {
      "title": "IPCC (2006) 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Vol. 3 Industrial Processes and Product Use, ch. 3.6 Carbide production (default factors; read through EPA 2009, chapter not audited)"
    },
    {
      "title": "Fraunhofer IKTS (2023) Energy-efficient and low in emissions: silicon carbide recycling with RECOSiC (press release; conventional Acheson electricity per t SiC)",
      "url": "https://www.fraunhofer.de/en/press/research-news/2023/june-2023/energy-efficient-and-low-in-emissions-silicon-carbide-recycling-with-recosic.html"
    },
    {
      "doi": "10.1002/14356007.a23_749.pub2",
      "title": "Ullmann's Encyclopedia of Industrial Chemistry: Silicon Carbide (route reference lead from issue #179; production sections not audited in this run)"
    },
    {
      "title": "Chase, M. W. (1998) NIST-JANAF Thermochemical Tables, 4th ed., J. Phys. Chem. Ref. Data Monograph 9 (formation enthalpies; values to be checked)"
    }
  ],
  "repository": {
    "access": "public",
    "path": "processes/silicon-carbide-1",
    "url": "https://github.com/ChemE-as-Code/process-library"
  },
  "representations": [
    {
      "bytes": 31878,
      "id": "BFD",
      "kind": "bfd",
      "preview": "artifacts/silicon-carbide-1/BFD.svg",
      "source": "process/BFD.xml",
      "status": "preview",
      "title": "Block flow diagram"
    },
    {
      "bytes": 102842,
      "id": "PFD",
      "kind": "pfd",
      "preview": "artifacts/silicon-carbide-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": "Crude crystalline silicon carbide from silica sand and petroleum coke in batch Acheson resistance furnaces: gas burn-off over the charge, ingot cooling, breaking and sorting with recycle of the unreacted mix, crushing. Electricity per kg, CO and SO2 explicit. Concept stage, assumed basis.",
  "title": "Silicon carbide by the Acheson process (5000 kg/h crude SiC, concept)",
  "validation": {
    "notes": "Concept BFD/PFD with closed mass, component and element balances (cheme validate, cheme process streams: 4 blocks, 7 steps, reactive balances by extents). All flows and compositions are specified values of an independent balance (scripts/sic_balance.py) on assumed yields, grades and splits; no furnace heat transfer, kinetics or SiO/CO gas-solid model is calculated. cheme process furnace supports limestone calcination only and refuses carbothermal SiC, so the furnace electricity is a labelled specific-energy basis; no property package covers the solids or the hot furnace gas, so energy closure is a lumped script estimate. cheme maturity supports no calculation maturity level until the feeds, conversions and sorting split are given with sources; concept is the lowest level the manifest allows. The gate-to-gate LCI is preliminary, with every background unmapped: its climate value (about 2.0 kg CO2-eq per kg, with its interval) is the DIRECT furnace CO2 and CH4 only, NOT a carbon footprint; electricity (about 7.7 kWh/kg, the largest exchange), coke, sand and landfill are gaps, and fossil CO (0.41 kg/kg) is not characterised (about 0.64 kg CO2-eq/kg more if counted as oxidised to CO2). Not reviewed.",
    "status": "unreviewed"
  },
  "viewer": {
    "commit": "c3ab3488c602bc797fdc98feffd4578375150dd0",
    "dirty": false,
    "sheets": [
      "process/BFD.xml",
      "process/PFD.xml"
    ],
    "skipped": [],
    "snapshot": "snapshots/silicon-carbide-1/",
    "stale": false,
    "tool": "cheme-as-code 1.6.0",
    "views": [
      "checks",
      "streams"
    ]
  }
}