ground granulated blast furnace slag production, UPR, ecoinvent 3.6, Undefined
Location: GLO - Global
This dataset represents the treatment of molten blast furnace slag, producing an output of ground granulated blast furnace slag (GGBFS, also referred to as slag cement). This GLO dataset is an extrapolation from the US datasets. The activity is identified to as a case of specialty production, i.e. it depends on a material for treatment as input but it has a positive reference product as an output and which determines the production volume cf. ecoinvent Data Quality Guidelines ch 11.6. [The following text and LCI is mainly based on the work of Marceau and VanGeem (2003), available from http://www.slagcement.org/Sustainability/Sustainability.html.] GGBFS is a supplementary cementious material used as a partial replacement for Portland cement in concrete. Blast furnace slag is generated as a by-product of hot metal production in blast furnaces, in which iron-bearing ores and pellets are reduced to iron (the process is sometimes also referred to as pig iron production). The liquid metal and the slag are regularly tapped from the blast furnace and separated. Three main routes exist for the treatment of the hot blast furnace slag: (i) Air-cooling results in aggregates which can be used for asphaltic paving, fill, road bases and as a feed for cement kilns. (ii) Pelletized slag is commonly used for lightweight aggregates. (iii) GGBFS is produced by quenching the hot blast furnace slag with water followed by grinding. GGBFS is predominantly used as a partial substitute for Portland cement in concrete mixes or in blended cements. This inventory for production of GGBFS encompasses the process steps (i) quenching/granulation, (ii) dewatering and/or drying, (iii) crushing, (iv) grinding, and (v) storage in pile and silo. The dataset is mainly based on the LCI of slag cement by Marceau & VanGeem (2003), which was based on a survey of the members of the Slag Cement Association in the US. The functional unit of the original work represented the output of 1 short ton of slag cement, i.e. GGBFS, which for the purpose of this ecoinvent LCI was converted to the treatment of 908.5 kg molten blast furnace slag (which corresponds to the output of 907.2 kg GGBFS plus the generated solid waste and particulate matter emissions). Metal emissions to air was omitted due to lack of data. The LCI data of Marceau & VanGeem (2003) was complemented with emission factors for wastewater from European Commission's Best Available Techniques (BAT) Reference Document for Iron and Steel Production - Draft in Progress (24 June 2011).
[The formula for the release of CO2 to air contained an error in the original submission; dataset corrected and resubmitted on 2017-11-22]
Undefined unit processes (UPRs) are the unlinked, multi-product activity datasets that form the basis for all of the system models available in the ecoinvent database. This is the way the datasets are obtained and entered into the database by the data providers. These activity datasets are useful for investigating the environmental impacts of a specific activity (gate-to-gate), without regard to its upstream or downstream impacts.
LCI based on industry average in 2001-2002
ecoinvent EULA