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Flue Gases

NAMES OF CHEMICAL FORMULA

3.3 CO 2 Storage Phase

The uncertainty associated with CCS at this stage is mostly that of legal consequence in terms of it regulatory implications, contractual relations and liability issues in a

302 According to a Greenfacts document published online as the Scientific Facts on CO2 Capture and Storage - Sourced from IPCC 2005 and Summary and Details: Greenfacts 2007.

It is concluded that this means of CO2 transportations only suitable and advisable for very small scale application. http://www.greenfacts.org/en/co2-capture-storage/co2-capture-storage-greenfacts-level2.pdf

303Id. Pg 6

Figure 16 The Trans Forcados Oil and gas pipeline leading to the Calabar Sea port in the Niger Delta area of Nigeria.

120 post closure stage, and the viability of risk assessment of the storage site vis-à-vis the site characterisation and selection.

There are a lot of variables that have not been adequately clarified and understood about the storage of CO2 under different geological formations and conditions both on the medium and long term. Although there are different geological storage projects presently undertaken especially in Annex 1 countries and the USA (Figure 17 shows the distribution map for the locations where CCS projects are planned for future and or are currently operating304), none so far is implemented on such a scale in any Non Annex 1 country apart from the In Salah CO2 project in Algeria, neither is there any successfully implemented for the CDM as provided by the current Modalities and Procedures regulatory framework. The possibility of CCS project taking place in a Non Annex 1 country could be enhanced consequent to the approval of appropriate methodology by the EB CDM.

For CO2 to be considered safely stored away for a long time, the following factors must be identified and duly considered, first a comprehensive risk analysis of the project in terms of the environmental impact on humans and ecosystem of the storage location,305 leakage (or seepage) issues need to be adequately resolved vis-à-vis the liability and remediation;306 regulatory and legal issues vis-à-vis the national and international regimes,307 cost implications on the project execution and the characterisation of the storage site.308 The impact assessment should result in a broad based and robust risk management strategy for such a project.

304 Note this distribution has no bearing to CDM since there is no indication of CCS been implemented under CDM when these locations were selected.

305 (Herzog, 2001 & Herzog and Golomb, 2004)

306Id.

307Id.

308Id.

121 Figure 17 A pictorial depiction of the GHG Life cycle from capture to

storage. Courtesy CO2CRC

Figure 18 Future and Current Locations of Geological Storage Sites

Source: IPCC Special report 2005 EU OPEC Roundtable on CCS Presentation 2006

122 3.4 Geological Formation for CO2 Sequestration

Geological CO2 sequestration can be defined as a systemic [and systematic] storage of carbon dioxide captured from industrial processes, fuel combustion or from fuel and minerals, in stable geological formations such as hydrocarbon fields and aquifers thus prevent its release into the atmosphere.309 The storage of CO2 can be carried out in geological formations which were depleted or previously used as oil and gas reservoirs (i.e. hydrocarbon fields), deep saline formations310 or in coal seams to displace methane absorbed in the coal. The IEA 2008 report on CCS identified regions that have large enough oil and gas geological basin as suitable for the storage of CO2. These regions include Nigeria for oil and gas while other countries like China and India have large deposit of coal in their territories.311 The storing away of gases in the earth’s natural occurring geological reservoir, biosphere and deep Ocean is a process that has been occurring over millions of years and forms the bases for the formation of carbonates minerals, natural gas, oil and coal312within the geology of the earth. It is estimated that the earth’s geological reservoir capacity is 100trillion cubic feet (5600 million tonnes) of CO2

313 and current utilised capacity is less than 0.1GtC/yr.314 See Table 5 for estimated Global capacity from different sources. Natural occurring CO2 field315 can be found in places like Pisgah Anticline, in Mississippi USA with a storage capacity of over 200Million tonnes of pure CO2 stored away for some 65 million year.316 But no evidence of such naturally occurring sources within the Nigerian geographical jurisdiction. The nearest of such occurrence to Nigeria can only be linked to Lake Nyos in Cameroun. See Box 2 for detailed discussion.

309Supra note (Torvanger 2005) pg. 694.

310 The Sleipner Project in the North Sea by the Norwegian company Statoil is an example of this. With over 1km into the seabed

311 IEA 2008

312 IPCC Special Report 2005

313Supra note (Interagency Task Force on CCS 2010)

314 (Herzog, 2001 & Herzog and Golomb, 2004)

315 Such fields give the confidence that CO2 can be stored away within the earth crust for millions of years with minimal risk impact on the environment.

316 Sam Holloway Monitoring and verification of CO2 retention at storage sites BGS

123 However, as mentioned above, geological sequestration of CO2 is achieved by the systematic injection and storing away of captured CO2 gas from industrial processes, fossil fuel and mineral exploration processes or fuel combustion, into stable

geological formation such as the depleted oil and gas reservoirs, coal seams, aquifers etc. in order to prevent its release into the atmosphere317 this would have a decisive impact on the level of CO2 in the atmosphere while more sustainable and climate friendly technologies are developed not only to mitigate global warming but also to bring about a lasting solution or solutions to the global warming challenges.