Alumina Plant

Contents

Overview | Asset Structure | Flow Equations | Input File (Standard Format) | Types - Asset Structure | Constructors | Examples

Overview

In Macro, the Alumina Plant asset represents a facility that produces alumina from bauxite using the Bayer process. This process consumes electricity, fuel (typically natural gas), and bauxite as feedstocks, and produces alumina and CO₂ emissions. The process has relatively low electricity consumption (approximately 0.15 MWh per tonne of alumina) compared to aluminum smelting.

These assets are defined using either JSON or CSV input files placed in the assets directory, typically named with descriptive identifiers like alumina_plant.json or alumina_plant.csv.

Asset Structure

An Alumina Plant is made of the following components:

• 1 Transformation component, representing the alumina production process.
• 5 Edge components:
  • 1 incoming Electricity Edge, representing electricity consumption (approximately 0.15 MWh per tonne of alumina).
  • 1 incoming Bauxite Edge, representing bauxite supply (approximately 2.4 tonnes per tonne of alumina).
  • 1 incoming Fuel Edge, representing fuel supply (typically natural gas, approximately 2.917 MWh per tonne of alumina).
  • 1 outgoing Alumina Edge, representing alumina production.
  • 1 outgoing CO₂ Edge, representing CO₂ emissions from fuel consumption.

Here is a graphical representation of the Alumina Plant asset:

Flow Equations

The Alumina Plant asset follows these stoichiometric relationships:

\[\begin{aligned} \phi_{elec} &= \phi_{alumina} \cdot \epsilon_{elec\_alumina\_rate} \\ \phi_{bauxite} &= \phi_{alumina} \cdot \epsilon_{bauxite\_alumina\_rate} \\ \phi_{fuel} &= \phi_{alumina} \cdot \epsilon_{fuel\_alumina\_rate} \\ \phi_{co2} &= \phi_{fuel} \cdot \epsilon_{fuel\_emissions\_rate} \\ \end{aligned}\]

Where:

• $\phi$ represents the flow of each commodity
• $\epsilon$ represents the stoichiometric coefficients defined in the Conversion Process Parameters section.
• Note: Alumina and Bauxite flows are in tonnes, while Electricity and Fuel are in MWh.

Input File (Standard Format)

The easiest way to include an Alumina Plant 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/
│   ├── alumina_plant.json    # or alumina_plant.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 an Alumina Plant asset.

Transform Attributes

Essential Attributes

Conversion Process Parameters

General Attributes

Investment Parameters

Economic Parameters

Constraints Configuration

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

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

{
    "transform_constraints": {
        "BalanceConstraint": true
    },
    "edges":{
        "alumina_edge": {
            "constraints": {
                "CapacityConstraint": 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 an Alumina Plant asset.

Default constraints

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

• Balance constraint (applied to the transformation component)
• Capacity constraint (applied to the output alumina edge)

Types - Asset Structure

The Alumina Plant asset is defined as follows:

struct AluminaPlant{T} <: AbstractAsset
    id::AssetId
    aluminaplant_transform::Transformation
    elec_edge::Union{Edge{<:Electricity},EdgeWithUC{<:Electricity}}
    alumina_edge::Edge{<:Alumina}
    bauxite_edge::Edge{<:Bauxite}
    fuel_edge::Edge{<:T}
    co2_edge::Edge{<:CO2}
end

Where T is a generic type parameter that can be any Commodity type (typically NaturalGas).

Constructors

Factory constructor

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

Stoichiometry balance data

aluminaplant_transform.balance_data = Dict(
    :elec_to_alumina => Dict(
        elec_edge.id => 1.0,
        fuel_edge.id => 0.0,
        bauxite_edge.id => 0.0,
        alumina_edge.id => get(transform_data, :elec_alumina_rate, 0.0)
        ),
        :bauxite_to_alumina => Dict(
            elec_edge.id => 0.0,
            fuel_edge.id => 0.0,
            bauxite_edge.id => 1.0,
            alumina_edge.id => get(transform_data, :bauxite_alumina_rate, 0.0)
        ),
        :fuel_to_alumina => Dict(
            elec_edge.id => 0.0,
            fuel_edge.id => 1.0,
            bauxite_edge.id => 0.0,
            alumina_edge.id => get(transform_data, :fuel_alumina_rate, 0.0)
        ),
        :emissions => Dict(
            fuel_edge.id => get(transform_data, :fuel_emissions_rate, 0.0),
        co2_edge.id => 1.0
    )
)

Examples

This example illustrates a basic Alumina Plant configuration in JSON format:

{
    "AluminaPlant": [
        {
            "type": "AluminaPlant",
            "global_data":{
                "nodes": {},
                "transforms": {
                    "timedata": "Alumina"
                },
                "edges":{
                    "alumina_edge": {
                        "commodity": "Alumina",
                        "unidirectional": true,
                        "has_capacity": true,
                        "can_retire": true,
                        "can_expand": true,
                        "integer_decisions": false
                    },
                    "elec_edge": {
                        "commodity": "Electricity",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "bauxite_edge": {
                        "commodity": "Bauxite",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "fuel_edge": {
                        "commodity": "NaturalGas",
                        "unidirectional": true,
                        "has_capacity": false
                    },
                    "co2_edge": {
                        "commodity": "CO2",
                        "unidirectional": true,
                        "has_capacity": false,
                        "end_vertex": "co2_sink"
                    }
                }
            },
            "instance_data":[
                {
                    "id": "alumina_plant_1",
                    "transforms":{
                        "elec_alumina_rate": 0.15,
                        "bauxite_alumina_rate": 2.4,
                        "fuel_alumina_rate": 2.917,
                        "fuel_emissions_rate": 0.181048235160161
                    },
                    "edges":{
                        "alumina_edge": {
                            "end_vertex": "alumina_node_1",
                            "existing_capacity": 0.0,
                            "investment_cost": 3600000,
                            "fixed_om_cost": 613200,
                            "variable_om_cost": 30
                        },
                        "elec_edge": {
                            "start_vertex": "elec_node_1"
                        },
                        "bauxite_edge": {
                            "start_vertex": "bauxite_node_1"
                        },
                        "fuel_edge": {
                            "start_vertex": "natgas_node_1"
                        },
                        "co2_edge": {
                            "end_vertex": "co2_sink"
                        }
                    }
                }
            ]
        }
    ]
}

See Also

• Edges - Components that connect Vertices and carry flows
• Transformations - Processes that transform flows of several Commodities
• Nodes - Network nodes that allow for import and export of commodities
• Vertices - Network nodes that edges connect
• Assets - Higher-level components made from edges, nodes, storage, and transformations
• Commodities - Types of resources stored by Commodities
• Time Data - Temporal modeling framework
• Constraints - Additional constraints for Storage and other components
• Aluminum Smelting - Primary energy-intensive aluminum production process
• Aluminum Refining - Aluminum refining from scrap