Integrated Blast Furnace Basic Oxygen Furnace (with and without CCS)

Overview

In Macro, the Blast Furnace–Basic Oxygen Furnace (BF-BOF) pathway represents coal-based integrated steelmaking facilities that produce crude steel. In this configuration, iron ore is first reduced in the blast furnace using coke derived on-site from metallurgical coal to produce pig iron, which is then converted into crude steel in the basic oxygen furnace. These assets are defined using either JSON or CSV input files placed in the assets directory, typically named with descriptive identifiers like integrated_blast_furnace_basic_oxygen_furnace.json or integrated_blast_furnace_basic_oxygen_furnace_ccs.csv.

Asset Structure

A BF-BOF plant (with and without CCS) is made of the following components:

1 Transformation component, representing the BF-BOF (with and without CCS).
9 Edge components:
- 1 incoming IronOre Edge, representing iron ore supply in the form of the IronOreBF subcommodity. (Macro distinguishes between two iron ore sub-commodities: IronOreBF, a blast-furnace-grade ore with approximately 65% iron content, and IronOreDR, a higher-purity ore (above ~67% iron) suitable for use in direct-reduction furnaces.)
- 1 incoming MetCoal Edge, representing metallurgical coal supply.
- 1 incoming ThermalCoal Edge, representing thermal coal supply.
- 1 incoming SteelScrap Edge, representing merchant steel scrap supply. (Steel scrap that is externally sourced, in contrast to home scrap, which is generated within the facility. Steel scrap is mainly used to limit overheating from the highly exothermic oxidation reactions in the BOF.)
- 1 incoming NaturalGas Edge, representing natural gas supply. (Natural gas can serve as a supplemental reductant to lower coke consumption, or be blended with process off-gases to generate heat and electricity.)
- 1 outgoing CrudeSteel Edge, representing crude steel production.
- 1 outgoing Electricity Edge, representing excess electricity production. (if CCS is present, the BF-BOF-CCS facility is a net importer and the electricity edge is an incoming edge.).
- 1 outgoing CO2 Edge, representing the CO2 that is emitted.
- 1 outgoing CO2Captured Edge, representing the CO2 that is captured (only if CCS is present).

Here is a graphical representation of the Blast Furnace Basic Oxygen Furnace asset without CCS:

%%{init: {'theme': 'base', 'themeVariables': { 'background': '#D1EBDE' }}}%% flowchart BT subgraph BF-BOF direction BT A1(("**IronOre**")) e1@-->B{{"**BF-BOF**"}} A2(("**MetCoal**")) e2@-->B{{"**BF-BOF**"}} A3(("**ThermalCoal**")) e3@-->B{{"**BF-BOF**"}} A4(("**SteelScrap**")) e4@-->B{{"**BF-BOF**"}} A5(("**NaturalGas**")) e5@-->B{{"**BF-BOF**"}} B{{"**BF-BOF**"}} e6@-->C1(("**Electricity**")) B{{"**BF-BOF**"}} e7@-->C2(("**CrudeSteel**")) B{{"**BF-BOF**"}} e8@-->C3(("**CO2**")) e1@{ animate: true } e2@{ animate: true } e3@{ animate: true } e4@{ animate: true } e5@{ animate: true } e6@{ animate: true } e7@{ animate: true } e8@{ animate: true } end style A1 font-size:15px,r:46px,fill:#A52A2A,stroke:black,color:black,stroke-dasharray: 3,5; style A2 font-size:15px,r:46px,fill:#8B4513,stroke:black,color:black,stroke-dasharray: 3,5; style A3 font-size:15px,r:46px,fill:#A0522D,stroke:black,color:black,stroke-dasharray: 3,5; style A4 font-size:15px,r:46px,fill:#2874A6,stroke:black,color:black,stroke-dasharray: 3,5; style A5 font-size:15px,r:46px,fill:#005F6A,stroke:black,color:black,stroke-dasharray: 3,5; style B fill:white,stroke:black,color:black; style C1 font-size:15px,r:46px,fill:#FFD700,stroke:black,color:black,stroke-dasharray: 3,5; style C2 font-size:15px,r:46px,fill:#566573,stroke:black,color:black,stroke-dasharray: 3,5; style C3 font-size:15px,r:46px,fill:lightgray,stroke:black,color:black,stroke-dasharray: 3,5; linkStyle 0 stroke:#A52A2A, stroke-width: 2px; linkStyle 1 stroke:#8B4513, stroke-width: 2px; linkStyle 2 stroke:#A0522D, stroke-width: 2px; linkStyle 3 stroke:#2874A6, stroke-width: 2px; linkStyle 4 stroke:#005F6A, stroke-width: 2px; linkStyle 5 stroke:#FFD700, stroke-width: 2px; linkStyle 6 stroke:#566573, stroke-width: 2px; linkStyle 7 stroke:lightgray, stroke-width: 2px;

Flow Equations

The BlastFurnaceBasicOxygenFurnace asset follows these stoichiometric relationships:

\[\begin{aligned} \phi_{ironore} &= \phi_{crudesteel} \cdot \epsilon_{ironore\_consumption} \\ \phi_{metcoal} &= \phi_{crudesteel} \cdot \epsilon_{metcoal\_consumption} \\ \phi_{thermalcoal} &= \phi_{crudesteel} \cdot \epsilon_{thermalcoal\_consumption} \\ \phi_{steelscrap} &= \phi_{crudesteel} \cdot \epsilon_{steelscrap\_consumption} \\ \phi_{elec} &= \phi_{crudesteel} \cdot \epsilon_{elec\_consumption} \\ \phi_{natgas} &= \phi_{crudesteel} \cdot \epsilon_{natgas\_consumption} \\ \phi_{co2} &= \phi_{crudesteel} \cdot \epsilon_{emission\_rate} \\ \phi_{co2\_captured} &= \phi_{crudesteel} \cdot \epsilon_{co2\_capture\_rate} \quad \text{(if CCS)} \\ \end{aligned}\]

Where:

$\phi$ represents the flow of each commodity
$\epsilon$ represents the stoichiometric coefficients defined in the Conversion Process Parameters section.

Input File (Standard Format)

The easiest way to include an integrated BlastFurnaceBasicOxygenFurnace asset in a model is to create a new file (either JSON or CSV) and place it in the assets directory together with the other assets.

your_case/
├── assets/
│   ├── integrated_blast_furnace_basic_oxygen_furnace.json    # or integrated_blast_furnace_basic_oxygen_furnace.csv
│   ├── other_assets.json
│   └── ...
├── system/
├── settings/
└── ...

This file can either be created manually, or using the template_asset function, as shown in the Adding an Asset to a System section of the User Guide. The file will be automatically loaded when you run your Macro model. An example of an input JSON file is shown in the Examples section.

The following tables outline the attributes that can be set for a BfBof.

Transform Attributes

Essential Attributes

Field	Type	Description
`Type`	String	Asset type identifier: "BlastFurnaceBasicOxygenFurnace"
`id`	String	Unique identifier for the asset instance
`location`	String	Geographic location/node identifier
`timedata`	String	Time resolution for the time series data linked to the transformation

Conversion Process Parameters

Field	Type	Description	Units
`ironore_consumption`	Float64	iron ore consumption per ton of crude steel output	$t_{ironore}/t_{crudesteel}$
`metcoal_consumption`	Float64	metallurgical coal consumption per ton of crude steel output	$t_{metcoal}/t_{crudesteel}$
`thermal_consumption`	Float64	thermal coal consumption per ton of crude steel output	$MWh_{thermalcoal}/t_{crudesteel}$
`steelscrap_consumption`	Float64	steel scrap consumption per ton of crude steel output	$t_{steelscrap}/t_{crudesteel}$
`electricity_production`	Float64	electricity production per ton of crude steel output	$MWh_{elec}/t_{crudesteel}$
`natgas_consumption`	Float64	natural gas consumption per ton of crude steel output	$MWh_{natgas}/t_{crudesteel}$
`emission_rate`	Float64	CO2 emissions per ton of crude steel output	$t_{CO2}/t_{crudesteel}$
`capture_rate`	Float64	captured CO2 emissions per ton of crude steel output, only relevant for CCS variant.	$t_{CO2}/t_{crudesteel}$

General Attributes

Field	Type	Values	Default	Description
`type`	`String`	Any Macro commodity type matching the commodity of the edge	Required	Commodity of the edge. E.g. "Electricity".
`start_vertex`	`String`	Any node id present in the system matching the commodity of the edge	Required	ID of the starting vertex of the edge. The node must be present in the `nodes.json` file. E.g. "elec_node_1".
`end_vertex`	`String`	Any node id present in the system matching the commodity of the edge	Required	ID of the ending vertex of the edge. The node must be present in the `nodes.json` file. E.g. "crudesteel_node_1".
`availability`	`Dict`	Availability file path and header	Empty	Path to the availability file and column name for the availability time series to link to the edge. E.g. `{"timeseries": {"path": "assets/availability.csv", "header": "BlastFurnaceBasicOxygenFurnace"}}`.
`has_capacity`	`Bool`	`Bool`	`false`	Whether capacity variables are created for the edge.
`integer_decisions`	`Bool`	`Bool`	`false`	Whether capacity variables are integers.
`unidirectional`	`Bool`	`Bool`	`false`	Whether the edge is unidirectional.

Asset expansion

As a modeling decision, only the CrudeSteel is allowed to expand. Therefore, both the has_capacity and constraints attributes can only be set for that edge. For all other edges, these attributes are pre-set to false and an empty list, respectively, to ensure the correct modeling of the asset.

Directionality

The unidirectional attribute is set to true for all the edges.

Investment Parameters

Field	Type	Description	Units	Default
`can_retire`	Boolean	Whether capacity can be retired	-	true
`can_expand`	Boolean	Whether capacity can be expanded	-	true
`existing_capacity`	Float64	Initial installed capacity	tCrudeSteel	0.0

Economic Parameters

Field	Type	Description	Units
`investment_cost`	Float64	CAPEX per unit capacity	$/tCrudeSteel/hr
`fixed_om_cost`	Float64	Fixed O&M costs	$/tCrudeSteel/hr
`variable_om_cost`	Float64	Variable O&M costs	$/tCrudeSteel

Constraints Configuration

BlastFurnaceBasicOxygenFurnace assets can have different constraints applied to them, and the user can configure them using the following fields:

Field	Type	Description
`transform_constraints`	Dict{String,Bool}	List of constraints applied to the transformation component.
`output_constraints`	Dict{String,Bool}	List of constraints applied to the output edge component.

For example, if the user wants to apply the BalanceConstraint to the transformation component and the MaxCapacityConstraint to the output edge, the constraints fields should be set as follows:

{
    "transform_constraints": {
        "BalanceConstraint": true
    },
    "edges":{
        "crudesteel_edge": {
            "constraints": {
                "MaxCapacityConstraint": true
            }
        }
}

Users can refer to the Adding Asset Constraints to a System section of the User Guide for a list of all the constraints that can be applied to the different components of a BfBof asset.

Default constraints

To simplify the input file and the asset configuration, the following constraints are applied to the BlastFurnaceBasicOxygenFurnace asset by default:

Balance constraint (applied to the transformation component)
Capacity constraint (applied to the output crude steel edge)
MustRun constraint (applied to the output crude steel edge)

Types - Asset Structure

The BlastFurnaceBasicOxygenFurnace asset is defined as follows:

struct BlastFurnaceBasicOxygenFurnace <: AbstractAsset
    id::AssetId
    bfbof_transform::Transformation
    ironore_edge::Edge{<:IronOre}
    metcoal_edge::Edge{<:Coal}
    thermalcoal_edge::Edge{<:Coal}
    steelscrap_edge::Edge{SteelScrap}
    natgas_edge::Edge{NaturalGas}
    crudesteel_edge::Edge{CrudeSteel}
    elec_edge::Edge{Electricity}
    co2_edge::Edge{CO2}
end

Constructors

Factory constructor

make(asset_type::Type{BlastFurnaceBasicOxygenFurnace}, data::AbstractDict{Symbol,Any}, system::System)

Field	Type	Description
`asset_type`	`Type{BlastFurnaceBasicOxygenFurnace}`	Macro type of the asset
`data`	`AbstractDict{Symbol,Any}`	Dictionary containing the input data for the asset
`system`	`System`	System to which the asset belongs

Stochiometry balance data

bfbof_transform.balance_data = Dict(
    :ironore_consumption=> Dict(
        crudesteel_edge.id => get(transform_data, :ironore_consumption, 0.0),
        ironore_edge.id => 1.0
    ),
    :steelscrap_consumption=> Dict(
        crudesteel_edge.id => get(transform_data, :steelscrap_consumption, 0.0),
        steelscrap_edge.id => 1.0
    ),
    :electricity_production => Dict(
        crudesteel_edge.id => get(transform_data, :electricity_production, 0.0),
        elec_edge.id => -1.0
    ),
    :metcoal_consumption => Dict(
        crudesteel_edge.id => get(transform_data, :metcoal_consumption, 0.0),
        metcoal_edge.id => 1.0
    ),
    :thermalcoal_consumption => Dict(
        crudesteel_edge.id => get(transform_data, :thermalcoal_consumption, 0.0),
        thermalcoal_edge.id => 1.0
    ),
    :natgas_consumption => Dict(
        crudesteel_edge.id => get(transform_data, :natgas_consumption, 0.0),
        natgas_edge.id => 1.0
    ),
    :emissions => Dict(
        crudesteel_edge.id => get(transform_data, :emission_rate, 0.0),
        co2_edge.id => -1.0,
    )
)

Dictionary keys must match

In the code above, each get function call looks up a parameter in the transform_data dictionary using a symbolic key such as :metcoal_consumption or :emission_rate. These keys must exactly match the corresponding field names in your input asset .json or .csv files. Mismatched key names between the constructor file and the asset input will result in missing or incorrect parameter values (defaulting to 0.0).

Examples

This example illustrates a basic BlastFurnaceBasicOxygenFurnace configuration in JSON format, featuring standard parameters in a three-zone case.

{
    "BlastFurnaceBasicOxygenFurnace": [
        {
            "type": "BlastFurnaceBasicOxygenFurnace",
            "global_data":{
                "nodes": {},
                "transforms": {
                    "timedata": "CrudeSteel"
                },
                "edges":{
                    "crudesteel_edge": {
                        "commodity": "CrudeSteel",
                        "unidirectional": true,
                        "has_capacity": true,
                        "can_retire": true,
                        "can_expand": true,
                        "integer_decisions": false
                    },
                    "ironore_edge":{
                        "commodity": "IronOreBF", 
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "metcoal_edge": {
                        "commodity": "MetCoal",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "thermalcoal_edge": {
                        "commodity": "ThermalCoal",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "steelscrap_edge":{
                        "commodity": "SteelScrap",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "elec_edge":{
                        "commodity": "Electricity",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "natgas_edge": {
                        "commodity": "NaturalGas",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "co2_edge": {
                        "commodity": "CO2",
                        "unidirectional": true,
                        "has_capacity": false,
                        "end_vertex": "co2_sink_steel"
                    }
                }
            },
            "instance_data":[
                {
                    "id": "SE_bfbof",
                    "transforms":{
                        "ironore_consumption": 1.12,
                        "metcoal_consumption": 0.44,
                        "thermalcoal_consumption": 0.38,
                        "steelscrap_consumption": 0.26,
                        "electricity_production": 0.23,
                        "natgas_consumption": 0.06,
                        "emission_rate": 1.79
                    },
                    "edges":{
                            "crudesteel_edge": {
                                "end_vertex": "crudesteel_SE",
                                "existing_capacity": 0.0,
                                "investment_cost": 2846124,
                                "fixed_om_cost": 56922,
                                "variable_om_cost": 148
                            },
                            "metcoal_edge": {
                                "start_vertex": "metcoal_source"
                            },
                            "thermalcoal_edge": {
                                "start_vertex": "thermalcoal_source"
                            },
                            "elec_edge":{
                                "end_vertex": "elec_SE"
                            },
                            "natgas_edge":{
                                "start_vertex": "natgas_SE"
                            },
                            "ironore_edge":{
                                "start_vertex": "ironorebf_source"
                            },
                            "steelscrap_edge":{
                                "start_vertex": "steelscrap_source"
                            }

                        }
                },
                {
                    "id": "MIDAT_bfbof",
                    "transforms":{
                        "ironore_consumption": 1.12,
                        "metcoal_consumption": 0.44,
                        "thermalcoal_consumption": 0.38,
                        "steelscrap_consumption": 0.26,
                        "electricity_production": 0.23,
                        "natgas_consumption": 0.06,
                        "emission_rate": 1.79
                    },
                    "edges":{
                            "crudesteel_edge": {
                                "end_vertex": "crudesteel_MIDAT",
                                "existing_capacity": 0.0,
                                "investment_cost": 2846124,
                                "fixed_om_cost": 56922,
                                "variable_om_cost": 148
                            },
                            "metcoal_edge": {
                                "start_vertex": "metcoal_source"
                            },
                            "thermalcoal_edge": {
                                "start_vertex": "thermalcoal_source"
                            },
                            "elec_edge":{
                                "end_vertex": "elec_MIDAT"
                            },
                            "natgas_edge":{
                                "start_vertex": "natgas_MIDAT"
                            },
                            "ironore_edge":{
                                "start_vertex": "ironorebf_source"
                            },
                            "steelscrap_edge":{
                                "start_vertex": "steelscrap_source"
                            }
                        }
                },
                {
                    "id": "NE_bfbof",
                    "transforms":{
                        "ironore_consumption": 1.12,
                        "metcoal_consumption": 0.44,
                        "thermalcoal_consumption": 0.38,
                        "steelscrap_consumption": 0.26,
                        "electricity_production": 0.23,
                        "natgas_consumption": 0.06,
                        "emission_rate": 1.79
                    },
                    "edges":{
                            "crudesteel_edge": {
                                "end_vertex": "crudesteel_NE",
                                "existing_capacity": 0.0,
                                "investment_cost": 2846124,
                                "fixed_om_cost": 56922,
                                "variable_om_cost": 148
                            },
                            "metcoal_edge": {
                                "start_vertex": "metcoal_source"
                            },
                            "thermalcoal_edge": {
                                "start_vertex": "thermalcoal_source"
                            },
                            "elec_edge":{
                                "end_vertex": "elec_NE"
                            },
                            "natgas_edge":{
                                "start_vertex": "natgas_NE"
                            },
                            "ironore_edge":{
                                "start_vertex": "ironorebf_source"
                            },
                            "steelscrap_edge":{
                                "start_vertex": "steelscrap_source"
                            }
                        }
                }

            ]
        }
    ]
}