The AMEE category business/processes/production/ferroalloy/ch4 is aimed towards industry professionals to enable them to prepare inventories of greenhouse gas emissions from ferroalloy production. This category is designed for use alongside the ferroallloy tier 1 or tier 2 categories. The methodology provided by AMEE in this category represents the Tier 1 (default) and Tier 2 (user-supplied) approach for CH4 emissions calculation described by the IPCC Guidelines for National Greenhouse Gas Inventories (NGGIP).

The heating of carbon materials in the furnace releases volatiles including methane. With open or semi-covered furnaces – predominantly used for FeSi and Si ferroalloy production - most of the volatiles will burn to CO2 above the charge, in the hood and off-gas channels, but some will remain un-reacted as CH4 and NMVOC. The amounts depend on the operation of the furnace. Sprinkle-charging will reduce the amounts of CH4 compared to batch-wise charging. Increased temperature in the hood (less false air) will reduce the content of CH4 further. The errors associated with estimates or measurements of N2O emissions from the ferroalloys industry are very large and thus, a methodology is not provided.

How to use this category

Selecting an emissions scenario

To use this category use the typeOfAlloy drill-down to select the alloy type being used from the following options:

  1. si-metal
  2. fesi 90
  3. fesi 75
  4. fesi 65

A second drill-down must then be specified using the operationOfFurnace drill-down to select the operation type of the furnace used, from the following options:

  1. unknown
  2. batch-charging
  3. sprinkle-charging
  4. sprinkle-charging and over 750 degrees C

If unknown is selected, the default values used are those for sprinkle-charging operation.

Specifying activity data

The only required profile item value is productQuantity. The emission factor has a default value provided by the AMEE engine, but this can be over-ridden, using the massCO2PerMassProduct profile item value, by the user if more precise site or country-specific values are known. If using a site-specific emissions factor, the calculation represents the tier 2 IPCC NGGIP methodology.

Results and calculation

The returned amounts represent the CH4 emissions associated with the quantity specified. Two quantities are returned, as follows:

  • CH4: CH4 (methane) emissions
  • CO2e: CO2e emissions (CH4 converted using these global warming potential)

The individual quantity for CH4 represents an absolute quantity rather than a CO2e quantity.

Did you know?