Fixing Blast Furnace Steel Production Process

[toniseibold]

Coal demand for steel production via basic oxygen blast furnace was 1.43 MWh_coal/t_steel. This assumption based on mpp steel tracker documentation is too low.

Specific Emissions Accounting

Using an emissivity of coal of 0.3361 t_CO2/MWh_coal (following technology-data) would lead to 0.48 t_CO2/t_steel.
Which contradicts e.g this source (p.2)

Comparing the primary steel production (35.4 Mt_steel) with the emissions of 51 Mt_CO2 (https://www.wvstahl.de/wp-content/uploads/WV-Stahl_Daten-und-Fakten-2024_RZ-Web.pdf) for Germany would also indicate a higher demand for coal.

Changes proposed in this Pull Request

Using the data from the mpp steel tracker for BAT BF-BOF I come up with a coal demand of 5.34 MWh_coal/t_steel.

Checklist

• Code changes are sufficiently documented; i.e. new functions contain docstrings and further explanations may be given in doc.
• Data source for new technologies is clearly stated.
• Newly introduced dependencies are added to environment.yaml (if applicable).
  not applicable
• A note for the release notes doc/release_notes.rst of the upcoming release is included.
  not applicable
• I consent to the release of this PR's code under the GPLv3 license.

[toniseibold]

Neither the documentation nor the table provide any information about how much coal is minimum necessary.
If I read across the columns of all BF-BOF technologies, a minimum of Coke: 4.75371 and Met coal: 0.234942975 are necessary (technology BAT BF-BOF_bio PCI) assuming that gaseous input streams can be provided from other sources or by processing coal.
In sum minimum 4.99 coal per ton steel if hydrogen or biomass can be co-utilized.
Conclusion: 5.34 is a fair assumption (cross checking with https://www.steelonthenet.com/resources/cost-models/bof.html) taking into account the heterogeneity of coal heating value and technologies.

[euronion]

Ok, thanks. :)

My only quarrel is that coal != coke != met coal. They serve different purposes and have different properties, thus cannot be directly substituted.
I'd be fine with adopting your value, but can you add the disaggregation to coke / met coal values into the comment for the entry?

Then it is RTM at your convinience.