section there will be mentioned the aims and the objectives of the project and
the research that has been done in order to complete the study.
is aiming to show the advantages and
disadvantages of current Carbon Capture and Storage technologies and their
effectiveness at reducing the disaffects
of anthropogenic climate change.
objectives are to examine the Carbon Capture and Storage technologies, according
their positives and negatives. Also to identify the best way to record the anthropogenic climate change.
Most of the environmental problems start during the industrial
revolution, since then they have been increased dramatically. In addition to that
during the last 200 years the human population have been growth rapidly
from 1 to 6.5 billion.
Before the Industrial
Revolution in the 19th century, global average CO2 was about 280 ppm. CO2 is one of the most
notorious greenhouses gases produced from human activity. The consetation of CO2 in the globe is increasing, that phenomenon has
been noted over the years from the environmentalists worldwide. From 1995 to
2001, average global CO2 emissions increased at a rate of 1.4% per year. While
this increase is slower than the increase in use of primary energy, it is
higher than the increase in CO2 emissions over the past 5 years.
There is sufficient evidence to
show that human activities have contributed significantly to the gradual
warming of the Earth over the past 50 years. According to the Australian
Greenhouse Gas Inventory, in 2006, 576.0 million tones CO2-equivalent (CO2e) were
released from human activities. Carbon dioxide was the most significant of
greenhouse gases in Australia’s inventory, making up 74.3% (427.8 million
tonnes) of total CO2 emissions.
Electric power generation is the greatest contributor to CO2 gas emissions , as
it produce approximately 50% of the total CO2 that are produced. Another
huge factor of CO2 emitions is the transport sector.
on December 2017, the average CO2 level at Mauna Loa, Hawaii, was at 406.75ppm, which
was 1.61ppm higher than the average for November 2016 5, although the biggest
ever increase over the period of a year was from 2015 to 2016. In addition, it
was very different from the CO2 levels at the period before the Industrial
Revolution. While some of the increase in CO2 levels can be attributed to the El
Niño phenomenon, a significant portion of it was due to activities of humans.
Business-as-usual emission scenarios for
fossil fuel emissions suggest that atmospheric CO2 could peak
in 2,250 AD at ?2,000?p.p.m. CO2 values
as high as this were last seen in the Triassic around 220–200?Myrs. Some
studies claim that greenhouse gas emissions have decreased recently. Although those
studies have consider only the emissions for the generation of energy according
to the estimations that each country made. Changes in land use, including the
effects of deforestation and the loss of land have not considered.
sensitivity of the correlation between increasing atmospheric CO2 levels and climate change has spot
an increase in the research and development for techniques that produce energy
with clean methods and that is renewable also. However, the fast tempo which temperature at the globe is increasing, will demand drastic actions for
reduction in CO2 emissions, that means restriction of the old ways for energy production
and establishment of new clean energy
production ways that are also renewable. In order to combat the rising levels
of CO2, Carbon Capture and Storage (CCS) technologies have gained the
attention of researchers and environmentalists worldwide. This study will investigate
three of the most promising CCS technologies that will help at the reduction of
the anthropogenic climate change: (1) biomass carbon sequestration, (2) geographical sequestration, (3)
mineral carbon sequestration.
interesting way to isolate carbon would be using biomass. Biomass a material
that produced form living organisms. Specifically, the biomass is working as a storage for
energy as it uses H2O +CO2 +Solar Energy = Biomass + O2. As it can be understood there is no need for
large amount of human recourses as the primary need is Sun light. Crops are considered
good option for the production of biomass. Although there would be need for
large areas of planting fields in order to produce sufficient amount of
biomass. On the other hand the sources of machines and generally the
agriculture reassures would produce significant amount of CO2 in that scale. So the benefits of the biomass
would canceled with the CO2 emission that the agricultural sources would
The use of
algae for producing biomass would be more preferable in compare to the crops as
they do not demand cultivable land. The algae consume large amounts (80% to 99%
under optimum conditions) of CO2 as they grow and produce O2. There has been calculated
that an algal pond of 3600 acres would effectively capture 80% of a typical
200MWh natural gas-fired power plant’s CO2 emissions during daylight hours,
assuming an algal areal biomass productivity rate of 20g dry weight per square
meter per day. From all the above it can be understood that the Algae is the
most suitable method for CO2 capture than the crops.
way to store CO2 in a stable form of carbon is the biochar wich holds 90% of
carbon. Its produced by pyrolysis which
is the direct thermal decomposition
of biomass in the absence of oxygen, which produces a mixture of solids, liquid,
and gas products. Also pyrolysis creates gases such as hydrogen and methane,
which are combustible fuel.
Geologic sequestration demands 3 processes:
capturing CO2, transporting CO2 , and placing theCO2
in a geologic formation for
permanent or semi-permanent storage. The carbon dioxide is placed into the
geologic formation using the system of injection wells. An injection well is like an oil well or water
well, despite that instead of pumping oil or water out of the ground, CO2 is injected into the well.
Injection wells are also used for the disposal of various types of wastes and
to enhance oil recovery in some areas. There
are studies that are suggesting to use deep saline aquifers that are deeper
than 1km from Earth’s surface, deeper than the freshwater sources, as a storage
place for the CO2 that
would be liquefied. The mechanisms for storing or isolating CO2 at aquifers are the followings, (a) Dissolution of
CO2 into the aquifer water, (b) Hydrodynamic trapping of a CO2 plume, (c) Occurrence of geochemical
reactions between CO2 and the aquifer fluids or rocks to form stable solids
carbonates. The geochemical reactions of CO2, aquifer fluids and rocks are
proceeding at a relatively slow pace. Although it has been discovered that high
concentrations of silicates in aquifers are accelerating the geochemical
There are 2 types of aquifers the freshwater aquifers and the saline
aquifers. As it can be understood the
freshwater aquifers are vital as they are drinking water and they are extremely
protected. Also the freshwater aquifers are shallower than the saline ones,
another factor is that the freshwater cannot hold high pressure as the saline
ones so they are not practical for efficient storage CO2 . In conclusion freshwater aquifers are not good location for geological
sequestration. On the other hand the saline ones are deeper and there is more
knowledge on that technology due to the injection technology. Also due to their
depth are making a better sealing with the outer surface so they are more
secure. However, their high level of availability makes them useful as they can
source big volume of CO2.
the aquifers there are also depleted oil and gas field that with the technique
of Enhanced Oil Recovery (EOR) they can extract most of the amount of oil and
gas that is trapped in the fields, which in other case it would be unrecoverable.
By that way CO2 would be stored as the injected CO2 will reach with the oil.
Also those fields have proved their reliability due to the fact that they were
storage or oil and gas for thousands to millions of years. Another important
factor is that they are well known as they have been studied on the past and
they are capable of storing huge amounts of CO2
Mineral carbon sequestration
Mineral carbon sequestration is the reaction of CO2 with
a compound that gives a thermally stable and poorly
soluble carbonates at ambient conditions. Those carbonates contain
the following elements iron, magnesium and calcium. From those elements mainly
the magnesium silicates and the calcium silicates are the most common for
carbon sequestration, those materials are also well known around the word. On
the other hand, iron has a great value for making steel so I does not applies
for carbon sequestration use. Although, Australia seems to differ on that
mater as it is known to have big amounts of low-grade magnetite which can be
used for sequestration.
In our days precipitated calcium carbonate is produced form carbonating
calcined limestone which is a calcium oxide but this procedure produce amount
of CO2 that is similar to the amount needed for the calcium carbonate
formation. As it can be understood this procedure would create a vicious
circle. Also it would be impossible a batch of calcined limestone to carbonate
entirely. So insead of beneficial this procedure would be problematic as I
would release CO2 to the environment.
Apparently there is great
value at the steel slugs, the iron slugs and the materials that based to cement
as they have very high comprehensiveness at oxides of magnesium and calcium. Additionally,
the slugs of steel have been proved to be able to carbonate very easy without
the need of high pressure and temperature this has been also proved from W. Huijgen, G.-J.
Witkamp and R. Comans that calcium conversions of over 70% are possible at relatively mild process
conditions (d<106•m, T=200°C, O2=10bar, t=15min) without any further pretreatment or addition of chemicals. Furthermore there is high availability of slugs and it is also predicted to be a rising of the production of steel and iron slugs in a global scale. This method is very promising as it allows benefiting the slugs for capturing CO2 by carbonation. Last but not list it would be also beneficial as it counteract the steel industrial wastes The key to climate change Using the chart above we can list the biomass as the method with less Carbon storage capacity but at short period of time, the injection of CO2 underground has less storage capacity in compare to mineral carbonate although it demands less time to achieved which is still significant. The mineral carbonates are able to store more CO2 but the demand plenty more time. Although the mineral carbon sequestration is a safer approach as the product is solid at ambient condition in compare to the underground injection which run the risk of licking. CO2 licking will cause big damage to the area around the leak. As it has been noted previously all the methods for CO2 sequestration have their own limitations. Although there are more obstacles to the application of those methods. Firstly the techniques that are used for the production of electricity are interfering with the cost for the CO2 capture. For example courtiers that are using natural gas, black coal and brown coal to generate electricity are producing plenty of CO2, in order to capture most of it there is need for large and costful chemical facilities. Also the places that injection well would take place might be in a large distance. As a result of the factors the cost building the facilities and sequestration CO2 will be significant, resulting the method of geologic sequestration to be restricted to certain areas. Also most of the modern power plants have been builded without the scope of including carbon capture equipment and I would be costful to do the appropriate modification so they can be able to capture it. Apparently as the amount of captured CO2 would raise, the cost to storage it would also rise as the cheapest locations would have been filled and then there would be need for more locations. With the current data it is not easy the cost for carbon capture and storage to be estimated The target for reducing the CO2 emittions can be achieved easier by using the carbon capture methods instead of trying to replace all the existing power generation method with renewable as the renewable are still on an early stage and they are not capable to cover the needs of the entire planet. During the first steps of the transaction to renewable energy sources the geological sequestration would be more efficient in compare to other carbon capture methods as of its cost and the fast delivery of results. Many oil companies can also get involved as they can use CO2 in liquid and high pressure form as a mechanism to extract any trapped oil or gas. Furthermore as the cost for geological sequestration would raise due to the decease of sedimentary basins availability, the mineral carbon sequestration will be the best available solution as the mineral carbon sequestration forms inert carbonates that are easy and safe for disposal. There is need for the mineral carbon sequestration to be developed and use slugs from iron and steel instead of natural oxides and silicates due to their low availability Despite the fact that biomass carbon sequestration needs more time to give sufficient results it can be an efficient approach in long term without interfering to other environmental actions. Wisely it would be important biomass carbon sequestration methods to develop parallel to mineral carbon sequestration and geological carbon sequestration.