In
his PhD thesis, Antti Arasto, Business Development Manager at VTT
Technical Research Centre of Finland, conducted a comprehensive
techno-economic assessment of the application of carbon dioxide capture
and storage technology (CCS) in the steel industry. The dissertation
shows that there are significant possibilities for the steel industry to
reduce its carbon dioxide emissions.
In
his thesis, Antti Arasto assessed two major carbon dioxide capture
technologies, one of which is based on recycling waste gas in an oxygen
blast furnace and the other on post-combustion carbon capture from flue
gases. A full chain assessment of applications in the iron and steel
industry was performed in order to screen technology options and build a
development pathway to low carbon steelmaking for future carbon
constrained world.
The
results indicate that there are significant technical opportunities
available for the steel industry to reduce its carbon dioxide emissions.
At best, the emission reduction could be up to 48–73% of the plant's
direct emissions. The net GHG impact of emission reduction is 45–62% of
the plant's direct emissions.
Both
alternative technological solutions are very sensitive to a number of
different cost factors. According to the results, the cost to the
plant's owner for an emission reduction equivalent to one ton of carbon
dioxide is estimated to be in the range of EUR 40–70. An oxygen blast
furnace process with flue gas recirculation was found to be slightly
less costly than capturing carbon dioxide from the flue gas. However,
the solution based on oxygen blast furnace requires greater changes in
the process environment than the post combustion capture option.
"It
is possible to reduce the plant's direct carbon dioxide emissions
significantly by means of the two technological solutions analysed in
this thesis. The volumes are meaningful in terms of their impact on
climate change. However, application of either technological solution
requires that the market price of carbon dioxide emissions increases to a
level reflecting the costs referred to above. In other words, the
cost-competitiveness of both solutions will improve if a binding
agreement is reached at the Paris Climate Conference which puts a higher
price on emissions and, thus, forces operators to reduce their carbon
dioxide emissions – a fact which, on the other hand, increases the risk
of carbon leakage to countries with more relaxed emissions regimes",
says Antti Arasto.
According
to Arasto, the introduction of these technologies would enable
achieving up to 4% of the reduction targets slated by the EU for the
Paris Climate Conference negotiations (INDC – Intended nationally
determined contribution) and approximately 9% of the European Union's
ETS share.
Steel industry as a source of carbon dioxide emissions
Steel
industry is one of the major industrial sources of carbon dioxide
emissions globally. The steel industry accounts for approximately 6% of
anthropogenic carbon dioxide emissions.
There
are several methods to reduce carbon dioxide emissions from the steel
industry, e.g. improved energy-efficiency, bio-based reducing agents,
use of hydrogen as reducing agent and CCS technology. Not all of them,
however, can be applied to conventional blast furnace based steelmaking
route, which is the most widely used production route of virgin steel.
All these options have their benefits and disadvantages, and e.g.
certain advanced reduction processes considered to have great inherent
potential are still in the early stages of development. This means that,
for the time being, CCS technology is one of the few options available
for significantly reducing the steel industry's carbon dioxide emissions
in the short and medium term, given the current production environment.
CCS technology
CCS
(Carbon Capture and Storage) is based on capturing of carbon dioxide in
power plants and industrial facilities. After capture, carbon dioxide
is purified, pressurised and transported to long-term storage locations
through pipelines or by tanker vessels. Current challenges of the
solution include the high volumes of carbon dioxide, uncertainties and
responsibility issues regarding long-term storage of carbon dioxide, and
the cost of CCS.
The
implementation of CCS technology solutions in Finland requires
transporting carbon dioxide outside Finland, because no geological
formations suitable for long-term storage have been discovered in
Finnish bedrock. The most promising storage locations are situated in
the North Sea and in the Barents Sea.
Antti
Arasto, MSc (Tech), will defend his dissertation “Techno-economic
Evaluation of Significant CO2 Emission Reductions in the Iron and Steel
Industry with CCS” at Aalto University on 27 November 2015 at 12:00.
Doctoral thesis online: http://www.vtt.fi/inf/pdf/ science/2015/S111.pdf