19 ECOLOGICAL , ECONOMIC AND SOCIAL ISSUES OF IMPLEMENTING CARBON DIOXIDE SEQUESTRATION TECHNOLOGIES IN THE OIL AND GAS INDUSTRY IN RUSSIA

The objective of this paper is to define the main approaches to the implementation of carbon dioxide sequestration technologies in the oil and gas industry in Russia, and also to identify ecological, economic and social issues of their usage. Promotion of the technology of carbon dioxide (CO2) sequestration by means of capturing and injecting it into underground reservoirs is a promising mechanism of reducing carbon dioxide concentration. Carbon capture and storage (CCS) technologies might be used to enhance oil recovery (EOR-CO2) and production by means of oil extraction and decreasing oil viscosity. Conceptual view of the potential of EOR-СО2 technologies within the context of oil and gas industry sustainable development are presented. Incentives of the CCS projects implementation are identified. On the basis of the conducted research a number of scientific research and practical areas of the CCS technology development are presented.


INTRODUCTION
The key challenges of global energy sector, such as deterioration of reserves quality, the increasing importance of energy-and resourcesaving technologies, environmental restrictions, the adoption of unconventional raw hydrocarbon sources, economic and technological sanctions, require undertaking interest in a new conception of sustainable development for oil and gas industry (OGI).The model of modern OGI development should reflect the change in priorities and the switch to the conception based on innovations and resources, in which resources exploitation is based upon rational usage of mineral resources, energy costs optimization and more complete extraction of the hydrocarbons.
The paradigm of modern sustainable development of Russian OGI should be grounded upon innovations, which form a high-tech, rational, ecologically-balanced system of operation of oil and gas production, transportation and refinery enterprises [Cherepovitsyn 2009].
The principles of Russian OGI operation in the modern economic conditions may and should provide for a use of sets of organizational and technical, economic solutions targeted on the adoption and implementation of environmental and nature conservation related technologies.That makes it possible to use the options of greenhouse gas reduction that are widespread in the Western countries in order to ensure energy-efficient development and rational usage of natural resources.
Promotion of the technology of carbon dioxide sequestration by means of capturing and injecting it into the underground reservoirs is a promising mechanism of reducing carbon dioxide (CO 2 ) concentration.When injecting CO 2 into the saline formations or oil and gas fields at depths exceeding 800 meters, one should consider mining and geological properties of the rock.The reservoirs should have high porosity in order to accumulate big amounts of carbon dioxide.The rocks inside are usually permeable, so that CO 2 can penetrate into the underground reservoirs.At the same time, the storage reservoirs should be covered with impermeable overlying rocks in order to prevent surface leakages.

MAIN APPROACHES TO THE IMPLEMENTATION OF CARBON CAPTURE AND STORAGE TECHNOLOGIES (CCS)
The coalbed storage might be implemented at shallow depths and is based on the CO 2 adsorption by the coal.The technical practicability of such a technology to the great extent depends on the coalbed permeability.
The CO 2 storage in oil and gas fields that are at the final production stage might be used to enhance oil recovery (EOR-CO 2 ) and production by means of oil extraction and decreasing oil viscosity [Cherepovitsyn et al. 2013].
Enhancing oil recovery by the EOR-CO 2 method may be characterized by the added value by usage of anthropogenic CO 2 , captured at power plants and industrial enterprises.Studies conducted by American experts showed that the worldwide potential of the EOR-CO 2 is 340 billion barrels of technically recoverable oil resources and the capacitive potential of CO 2 storage is 120,000 million tons.Large volumes of potential carbon dioxide storage in the oil reservoirs underline the interest in the EOR-CO 2 technologies [Beecy et al. 2004].
CO 2 utilized in the underground reservoirs might be considered reduced greenhouse gas emissions.If there is a functioning carbon market, it is also possible to get some extra profits from the carbonic acid utilization.
It should be noted that the "Energy Strategy 2030" forms a number of target indicators of oil production technological advancement, such as scaling up the implementation of industrial innovational technologies, enhanced oil recovery and intensified oil production.The gas, gas-water, thermal-gas, rheo-gas-chemical and thermal EOR methods were identified as priorities [Energy strategy of Russian Federation to 2030].
Experts estimate stimulating oil formation by gas, which includes injection of carbon dioxide, associated petroleum gas (APG), petroleum gas and flue gas to be one of the most effective and rational technological processes from the point of view of energy-and resource-saving and EOR.

POSSIBILITIES OF THE EOR-CO 2 TECHNOLOGIES IN THE CONTEXT OF OIL AND GAS INDUSTRY SUSTAINABLE DEVELOPMENT
The concept of OGI sustainable development under the strategic vision of potential vast usage of the CCS technology is presented in Figure 1.In the OGI, the CCS technologies are related to injection of the anthropogenic CO 2 into the oil formation in the first place.
The main problem of the EOR-CO 2 usage is the high price of anthropogenic CO 2 .The CCS technologies, as mentioned above, are a combination of three processes: capturing, transportation and geological storage.These processes (stages) differ from each other considerably in terms of technical and technological practicability and have different experience of practical application.Currently, most of the CCS projects serve the demonstration purpose, therefore, there is no definite way to evaluate the costs of CCS technology usage.The implementation costs of the CCS technology depend on particular project, technological features of capturing industrial enterprises, mining and geological conditions of fields, distance of transportation etc.
According to the estimates from different experts, the cost of the CCS technologies varies from 1440 to 2136 rubles per ton of CO 2 .The cost of capturing is 1087-1392 rubles per ton of CO 2 , the transportation cost is 179-266 rubles per ton, and the storage cost in oil and gas reservoirs is about 174-478 rubles per ton.Thus, the cost of storage on the onshore fields accounts for around 12% of the overall that of the CCS technology, whereas the offshore accounts for around 22% [Naucler et al. 2008, Toth et al. 2011].
Efficiency of the EOR-CO 2 technology usage also depends on the price of CO 2 on the carbon market.
It has to be mentioned that the CO 2 sequestration costs will differ at different stages of the technology development.Thus, at the demo stage (currently) projects are minor and focused on drawing attention of all the stakeholders to this technology in order to prove its efficiency and safety.At this stage, the cost of such projects remains rather high, especially at the CO 2 capturing stage.
In the future, when CCS technologies enter the early commercial stage, on account of the economies of scale and trainings, the costs of adoption will decrease by 35%.Later, by reach-ing of the commercial maturity stage the costs of CCS may decrease by extra 10-12%.
Economic constraints for the domestic oil and gas industry on the EOR-CO 2 technology usage under the possible creation of national carbon market or under the integration with the mechanisms of the European carbon credit market have to be identified.That would allow determining the price range and the critical pricing parameters of the CCS projects.
Injection of CO 2 into the oil reservoirs is a complex process, the precise prognosis of the EOR-CO 2 potential for Russian deposits may be determined by geological and economic modeling and detailed research of the potential reservoir capacity.The economic analysis of the EOR-CO 2 schemes is a research, whose implementation entails additional difficulties related to the necessity of the improvement of technical and technological approaches, including the selection and usage of oil production equipment, taking specific capital and operating costs into account, evaluation of geological and investment risks.
The majority of Russian oil and gas fields (Western Siberia) are located in the areas that are remoted from the main industrial CO 2 emission sources.The old oil and gas production ar- Furthermore, long-term storage of carbon dioxide in the geological reservoirs implies forming the mechanisms of monitoring the underground environment and evaluating the risks of potential release of CO 2 to the surface.It is necessary to understand who will be monitoring and controlling the CO 2 diffusion process in the underground formations over time.
There is also an interesting and important strategic problem of working out the mechanisms of interaction between the state, oil and gas companies, research institutes and environmental organizations to promote the CCS technologies, and EOR-CO 2 in particular.

CONCLUSIONS
Thus, the CCS technology is a promising mechanism of carbon dioxide concentration reduction and one of the methods of enhancing oil recovery (EOR-CO 2 ).On the basis of the conducted research a number of scientific research and practical areas of the CCS technology development are worth mentioning: • Knowledge generation with purpose of formation of scientific problems and priorities of the CCS technology usage in Russian Federation, • Formation of methodological approaches to evaluation and revaluation of geological reservoirs suitable for greenhouse gas conservation,

Figure 1 .
Figure 1.Conceptual view of EOR-СО 2 technologies opportunities within the context of OGI sustainable development

Figure 2 .
Figure 2. Incentives of the CCS projects execution

•
Building a system of geological and environmental maps, showing the places and potential of CO 2 storage in geological structures, emission sources and the required infrastructure, • Formation of conceptual framework of the national carbon market, • Modeling marginal operating and capital costs of the CCS technology adoption, depending on the prognoses of carbon market development and technical advancement, • Developing the mechanisms of interaction between the state and businesses in the CCS projects implementation, • Developing the technique of geological, environmental and investment risks evaluation of the CCS projects.