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Sean Monkman, CarbonCure Technologies, John Kline, Kline
Consulting, Dave Frankman, Sustainable Energy Solutions,
and Kirk Deadrick, Argos USA,
discuss the reduction of CO
2
emissions in cement production using CO
2
capture technology.
Introduction
CarbonCure Technologies led a team of five
companies demonstrating the world’s first integrated
CO
2
capture and utilisation (CCU) from cement for
concrete production in January 2018. To build upon
previous CO
2
capture demonstrations at cement
plants.
1,2,3
This represented the first project to
collect cement kiln CO
2
for subsequent utilisation
downstream at a ready-mixed concrete producer.
The Global CO
2
Initiative (GCI) estimates there
is a US$400 billion market opportunity for CO
2
utilisation products in the concrete sector alone,
4
with the potential to contribute 1.4 billion t
of annual CO
2
reductions by 2030. The Cement
Sustainability Initiative (CSI), a global effort by 23
major cement producers, with operations in more
than 100 countries, who are responsible for 30%
of the world’s cement production, has identified
CCS/CCU technologies as the primary innovation
focus and contributor to meet the sector’s CO
2
reduction targets.
5
However, the development of the
large-scale carbon sequestration sector as a whole
indicates that it will likely become a local solution for
only a few cement producers worldwide. Utilisation
strategies will grow in importance.
The project demonstrated a template for a
turn-key solution within the cement and concrete
industries to realise this opportunity, by capturing
and converting cement production CO
2
emissions
into value-added concrete for construction projects.
CO
2
emissions from the Argos Roberta cement plant
near Calera, Alabama, were captured by Sustainable
Energy Solutions’ cryogenic CO
2
capture technology,
and were transported by Praxair and reused in
Argos’ Glenwood (Atlanta) concrete operations,
equipped with CarbonCure’s CO
2
utilisation
technology.
Argos Roberta cement plant
The Argos Roberta cement plant is located near
Calera, Alabama. Activity started on the site in
1912 with the development of a lime kiln. Cement
production started in 1943, with two long dry kilns
constructed by the mid 1960s. Blue Circle purchased
the property from Martin Marietta in 1983 and a
modernisation project started in 2000. The site was
acquired by Lafarge in 2001 as part of its
Blue Circle acquisition. The plant was acquired
by Argos in 2011 and currently has the capacity
to produce 1.425 million tpy of clinker and
1.54 million tpy of cement.
The new 4500 tpd clinker production line started
1Q02. Limestone comes from an adjacent quarry and
is sorted by cross-belt analysers for either lime or
cement production. The new clinker line consists of
a Pfeiffer vertical raw mill feeding a KHD five-stage
preheater with Pyrotop precalciner and kiln. Clinker
is cooled in an IKN grate cooler. Cement is ground
in one of two finish ball mills. One mill supplied by
KHD and one mill supplied by Polysius. Both mills are
equipped with high-efficiency separators.
The primary fuel is locally produced coal. A single
Pfeiffer coal mill supplies ground fuel to both the
kiln and calciner. About 22 − 24% of the fuel mix is
shredded alternative fuels that are fed directly to the
precalciner. The plant has 48 000 t of cement storage
and includes a packing plant with a palletiser.
Cement is distributed by truck and rail.
Cement produced at Roberta has a specific
carbon impact of 836 kg CO
2
per tonne of cement