Evolution of Global Secondary Lead Production
5
alloys, in the past the key alloy used for battery grids, is reflected in the ILZSG’s
calculations of apparent consumption and, presumably, estimates of refined output
where no actual data is provided or available. However, the international movement
of other alloys is typically excluded except in those cases where the reporting country
does not make any clear distinction between alloys in its trade data. The historical
reason for the approach taken by the ILZSG is that the manufacture of alloys, other
than lead-antimony alloys, was accounted for as lead consumption in the country
making the alloys. In an era where alloys, other than lead-antimony, accounted for
a very small share of overall demand and only used in specialist applications, this
was a perfectly reasonable way to collate and analyse the data. However, today leadantinomy alloys account for a relatively small share of total alloy production and the
continued use of this old definition introduces distortions in the calculation of both
lead consumption and production.
While not an entirely satisfactory solution, CHR Metals has taken the view that,
unless lead which is traded internationally can be specifically identified as lead bullion
requiring further refining, for example, bullion shipped from the Mt Isa smelter in
Australia to the UK’s Northfleet lead refinery, this material should be accounted for
as lead destined for consumption and, therefore, as lead production in the country
of origin. In making this assumption care is taken to ensure that if lead has been
counted as being produced in country A, it is not then double-counted as production
in country B, even if some further refining and/or alloying takes place in country B
before the lead is used.
Collating all available reported production data and detailed analysis of trade flows
are two of the methods used by CHR Metals to estimate secondary lead production. A
third method involves modelling the demand for lead–acid batteries and, in particular,
demand for replacement batteries. This involves making assumptions about battery
life in various applications and geographical locations. This provides a figure for the
likely generation of battery scrap. From assumptions about local battery recycling
rates, it is then possible to estimate the volume of secondary lead recovered from
scrap batteries. A small allowance for other lead scrap may also be added in some
countries.
However, it is important to note that not all secondary lead production is from
operations recycling used lead–acid batteries. Over time, an increasing share of lead
output from so-called primary smelters
1 has been derived from lead-bearing wastes,
scrap, and residues, in addition to conventional lead and bulk concentrates. The feed
mix of primary smelters is not typically disclosed in public but CHR Metals makes
an estimate for the recovery of secondary lead by primary smelters based on its
own research. This is another area where CHR Metals’ data may differ from official
sources.
Some of the lead recovered by primary smelters is derived from the lead contained
in zinc and other concentrates, so-called second-pass material (Whether or not this
1 CHR Metals defines all smelters than were originally designed to process lead concentrate as
primary smelters. This is the case even where, over time, the principal feed sources have become
secondary lead-bearing materials.
5
alloys, in the past the key alloy used for battery grids, is reflected in the ILZSG’s
calculations of apparent consumption and, presumably, estimates of refined output
where no actual data is provided or available. However, the international movement
of other alloys is typically excluded except in those cases where the reporting country
does not make any clear distinction between alloys in its trade data. The historical
reason for the approach taken by the ILZSG is that the manufacture of alloys, other
than lead-antimony alloys, was accounted for as lead consumption in the country
making the alloys. In an era where alloys, other than lead-antimony, accounted for
a very small share of overall demand and only used in specialist applications, this
was a perfectly reasonable way to collate and analyse the data. However, today leadantinomy alloys account for a relatively small share of total alloy production and the
continued use of this old definition introduces distortions in the calculation of both
lead consumption and production.
While not an entirely satisfactory solution, CHR Metals has taken the view that,
unless lead which is traded internationally can be specifically identified as lead bullion
requiring further refining, for example, bullion shipped from the Mt Isa smelter in
Australia to the UK’s Northfleet lead refinery, this material should be accounted for
as lead destined for consumption and, therefore, as lead production in the country
of origin. In making this assumption care is taken to ensure that if lead has been
counted as being produced in country A, it is not then double-counted as production
in country B, even if some further refining and/or alloying takes place in country B
before the lead is used.
Collating all available reported production data and detailed analysis of trade flows
are two of the methods used by CHR Metals to estimate secondary lead production. A
third method involves modelling the demand for lead–acid batteries and, in particular,
demand for replacement batteries. This involves making assumptions about battery
life in various applications and geographical locations. This provides a figure for the
likely generation of battery scrap. From assumptions about local battery recycling
rates, it is then possible to estimate the volume of secondary lead recovered from
scrap batteries. A small allowance for other lead scrap may also be added in some
countries.
However, it is important to note that not all secondary lead production is from
operations recycling used lead–acid batteries. Over time, an increasing share of lead
output from so-called primary smelters
1 has been derived from lead-bearing wastes,
scrap, and residues, in addition to conventional lead and bulk concentrates. The feed
mix of primary smelters is not typically disclosed in public but CHR Metals makes
an estimate for the recovery of secondary lead by primary smelters based on its
own research. This is another area where CHR Metals’ data may differ from official
sources.
Some of the lead recovered by primary smelters is derived from the lead contained
in zinc and other concentrates, so-called second-pass material (Whether or not this
1 CHR Metals defines all smelters than were originally designed to process lead concentrate as
primary smelters. This is the case even where, over time, the principal feed sources have become
secondary lead-bearing materials.