SWOC Analysis on CCS: A Case for Oxy-fuel Combustion CO2Capture System

M.Y. Han, Q. Yang, X.D. Wu, T.H. Wu G.Q. Chen,

1Laboratory of Systems Ecology, College of Engineering, Peking University, Beijing 100871, China

2Hubei Key Laboratory of Industrial Fume & Dust Pollution Control, Jianghan University, Wuhan, 430056, China

3State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China

4Department of New Energy Science and Engineering, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

SWOC Analysis on CCS: A Case for Oxy-fuel Combustion CO2Capture System

M.Y. Han1, Q. Yang2,3,4†, X.D. Wu1, T.H. Wu2,3, G.Q. Chen1,2,4†

1Laboratory of Systems Ecology, College of Engineering, Peking University, Beijing 100871, China

2Hubei Key Laboratory of Industrial Fume & Dust Pollution Control, Jianghan University, Wuhan, 430056, China

3State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China

4Department of New Energy Science and Engineering, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Submission Info

Communicated by Zhifeng Yang

SWOC analysis

Oxy-fuel combustion

CO2capture

CCS

Carbon capture and storage (CCS) has drawn worldwide attentions as a low-carbon technology alternative. Though China is deemed as a key player in the global context to slash CO2, the future of CCS in China is still highly uncertain. This study presents an overview for CCS development in China and gives detailed analyses on strengths, weaknesses, opportunities and constraints (SWOC) on CCS. Taking oxy-fuel combustion CO2capture system as a case in this study, much of the uncertainties rest in the lack of clarity about the technical mechanisms and high costs in air separation unit (ASU), given the fact that small-scale post-combustion and pre-combustion capture systems have been applied in industrial processes. Under such circumstances, high costs, immature technologies, lack of regulatory framework, and insufficiency of international collaboration are identified as the major factors affecting the development of CCS in China. Extensive attentions should be focused on these aspects, in particular the high costs and immature technologies coupled with CO2capture.

© 2013 L&H Scientific Publishing, LLC. All rights reserved.

1 Introduction

Carbon capture and storage (CCS) is currently being accounted as a key abatement technology option that can reduce global carbon dioxide (CO2) emissions. According to Intergovernmental Panel on Climate Change (IPCC), to achieve the target CO2reduction and climate change mitigation, all existing carbonabatement technologies including CCS should be taken into account [1]. In the Blue Map Scenario, International Energy Agency (IEA) [2] estimated that in the global context to cope with CO2reduction, CCS would help reduce the global CO2emissions by 9.1 Gt (19% of the total) in 2050, taking the largest share among all the CO2abatement technologies. Without CCS, the total cost for CO2reduction would increase by 70%. In recognition of that, organizations such as IEA considered that CCS should be deployed globally in a large scale [3].

In the global context, however, there are also some objections on CCS development. One argument is that CCS is an immature technology with some looming uncertainties in terms of the high cost and the long-term liability regime. In addition, some opponents hold that CCS does not actually mitigate CO2emissions by storing CO2underground, and it may take away the money invested in renewable energy and other abatement alternatives [4].

Currently, the cost of CCS today is relatively high, mainly originated from the high cost coupled with CO2capture technology. As the most costly part, CO2capture should be given adequate priority, which may be performed in different ways in terms of post-combustion, pre-combustion and oxy-fuel combustion [5]. Much attention has been focused on the researches for pre-combustion and post-combustion CO2capture domestically and abroad rather than for oxy-fuel combustion CO2capture. Pre-combustion capture is mainly used in integrated gasification combined cycle (IGCC) system. Since the renovation of existing pulverized coal (PC) boiler seems not to be a viable option, IGCC system can only be applied to newly established power plants. As for the pro-combustion capture, the massive energy consumption and high costs emerge as the main problems. Up to now, small-scale commercial post-combustion and precombustion capture systems have already been employed in industrial applications to separate CO2from mixed gases [6]. With regard to oxy-fuel combustion capture, despite its enormous potential to slash CO2emissions due to a high concentration of carbon dioxide in the flue gas, it is currently in the demonstration phrase and has not yet come into commercial application.

Several companies in China including Petro china, Shenhua, Sinopec, Huaneng, and Huadian, have been leading domestic CCS researches & demonstrations and are engaged in a number of international projects to accumulate initial knowledge of CCS demonstration. The two full scheme carbon capture, utilization and storage (CCUS) demonstration projects currently being in operation are Shenhua demonstration project (trapping capacity of 100,000 tons/year) and Sinopec Shengli Oil Field trapping and displacement of CO2(enhanced oil recovery, EOR) demonstration project (trapping capacity of 40,000 tons/year); the two million-ton level CO2trapping demonstration projects that have been put into operation are Huaneng Shanghai Shidongkou project (trapping capacity of 120,000 tons/year ) and Chongqing demonstration project voted by CLP (trapping capacity of 10,000 tons/year). Besides, the 35MWth national program supported oxy-fuel combustion demonstration project has been in construction, marking a landmark for China's self-developed carbon mitigation technology.

Extensive literatures have been carried out to support CCS deployment in China of technical, economic, environmental, and policy fronts. From a technical perspective, the status and outlook for the three major approaches to capture CO2were assessed [7]. Besides, related economic influences on coal plants related to CCS technology are presented by Lohwasser and Madlener [8]. Based on a life-cycle analysis, environmental evaluation of carbon capture and utilization were assessed [9]. Studies on policy suggestions on CCS were conducted as well, with the focus on establishment of a sound political framework for CCS [10-13].

Given the competitive relationship of renewable energy with CCS, the researches on various renewable systems should been given adequate considerations as well. The studies on solar power tower plants [14, 15], wind plants [16], biomass systems [17] and methane systems [18-19] have been carried out. Besides, nonrenewable energy costs and greenhouse gas emissions of wetlands [20-22] and eco-buildings [23-25] were analyzed. To support these analyses, ecological assessment on global scale [26, 27], national scale [28, 29] and urban scale [30-35] has been extensively developed. With full consideration of the domestic carbon emission situation, though capturing CO2emissions at their sources is the most practical approach, renewable systems with low costs and high acceptance appear as strong competitors for CCS.

Though the relevant available literatures provide a good overview of CCS deployment, a systems analysis is still in its vacancy. Since the appearance in the early 1950s, SWOC analysis has been applied as a prevailing analysis tool in the strategic management field [36]. Taking both internal and external factors into account, the SWOC analysis aims at maximizing the potential of strengths and opportunities while minimizing the effects of weaknesses and constraints [37]. It allows better-structured qualitative analysesof predefined issues and can be used to study the relevance and coherence of a policy or strategy in an intermediate or ex-post assessment context. Hence SWOC analysis is chosen as the tool to analyze the strengths, weaknesses, opportunities and constraints of CCS in this paper.

As the biggest CO2emitter in the world, China is deemed as a key player in the global CO2reduction effort [19]. In the IEA scenario, China will possess the most CCS projects in the world by a wide margin, with a projected 10-12 projects under way in 2020 before accelerating to 600 projects by 2050 [38]. Nevertheless, the future of CCS in China is still highly uncertain. High costs, immature technologies, lack of regulatory framework, and inadequacy of international collaboration are identified as the major factors affecting CCS development in China [12, 39, 40]. For the development of oxy-fuel combustion CO2capture, many of these uncertainties reside with the lack of clarity about the technical mechanisms and high costs in air separation unit (ASU). Under these circumstances, this study gives detailed analyses on strengths, weaknesses, opportunities and constraints (SWOC) rooted in a demonstration system equipped with oxy-fuel combustion CO2capture technology.

2 SWOC analysis on oxy-fuel combustion CO2capture system

2.1 Strengths

2.1.1 Immense potential to reduce CO2emissions

On the pathway to global CO2reduction, CCS could contribute at least 19% of the total CO2emission reduction by 2050. Without CCS, the total cost for CO2reduction would increase by 70%. This represents a higher proportion of CO2emission reductions compared with the contribution from renewable energy, and more than triple of the contribution from nuclear energy [2]. Besides, it is estimated that 77% of global energy needs are currently being satisfied with fossil fuels, while 40-60% of all the global CO2emissions are coming from stationary sources, such as power plants, refineries, and industrial facilities. Capturing these emissions at their sources is regarded as a feasible and promising approach for the moment.

With regard to oxy-fuel combustion capture, pure oxygen rather than air is used as the oxidant for combustion, which significantly eliminates the large amount of nitrogen that would otherwise stay in the flue gas stream. After the particulate matter (fly ash) is removed, the flue gas contains only water vapor and CO2plus small amounts of pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOx). The water vapor is easily removed by cooling and compressing the flue gas. Theoretically, oxy-fuel combustion system can capture all of the CO2produced.

2.1.2 Low cost

At present, the cost for CO2capture part in China’s demonstration projects is 0.19-0.25 Yuan/kWh [12]. Given the fact that almost all the power plants in China are PC plants, the oxy-fuel combustion capture owns a superior price advantage to pre-combustion technologies. In addition, the costs of construction and maintenance in an IGCC power plant are respectively 1.5 and 1.35 times higher than those in PC plants equipped with CO2capture technology [7]. Compared with renewable energy systems, the generation costs of oxy-fuel combustion capture system save much more than solar-generated energy cost at 1Yuan/kWh [12].

2.1.3 Demonstration projects

In the United States, the Department of Energy announced a grant of $1 billion in federal cost-sharing for the Future Gen 2.0 project in August 2010, under which an existing 200 MW oil-fired boiler at the Ameren power plant in Illinois would be replaced and repowered with a new supercritical coal-fired unit equipped with oxy-fuel combustion CO2capture facilities. Outside the United States, large-scale oxy-fuel combustion demonstrations are proposed in Canada, Germany, Spain, the U.K. and China. A 10 MW oxy-fuel combustion system equipped with CO2capture approach has been studied [1]. China’s National Science and Technology Support Program “35MWth oxy-fuel combustion capture key technologies, equipment researches and demonstration projects” has been officially initiated and is supposed to becompleted in early 2015. These projects provide precious experiences for the development of oxy-fuel combustion capture, including introduction of new equipment, design of principles and energy system process configurations.

2.1.4 Potential forCO2storage capacity

CO2storage is recognized as a major obstacle hindering CCS deployment. Capturing CO2from industrial sources is currently underway in China, and pre-combustion or post-combustion capture approaches are frequently employed. Once captured, CO2is compressed into a liquid state and transported via pipeline, truck or ship to a suitable storage location [41-42].

As for China, it possesses a vast land area with over 40% classified as sedimentary basins, which is the ideal geological setting for CO2storage. Preliminarily, theoretical estimates indicate that China is endowed with immense capacity for CO2storage at over 100 Gt [43-46]. A quantitative assessment of the potential storage sites (the Dagang and Shengli oil provinces, the deep saline aquifers nearby, and the Kailuan coal mining area) is performed along with a mapping of the possible transport infrastructure (by pipeline/truck or ship) that could be developed to connect CO2sources to sequestration sites. With regard to storage capacity, the largest capacity was found to reside in the deep saline aquifers (several Gt) but would require further geological investigation for delivering definite values. The storage potential in oil fields was found to be much smaller (less than 1 Gt) but could provide great opportunities for EOR. The coals of Kailuan mining area exhibit a favorable ability to adsorb CO2and provide enhanced coal bed methane (ECBM) recovery, but their infectivity remains to be verified.

2.1.5 Compatible with the current energy system

China domestically possesses a number of industries that could be equipped with CCS facilities, including power generation industry, chemical industry, and oil and gas industry. In principle, oxy-fuel combustion can be applied to both simple cycle and combined cycle power plants fueled by natural gas or distillate oil.

2.2 Weaknesses

2.2.1 High cost

High costs may lead to great uncertainties for developing CCS technology. On account of the experience from the demonstration projects, the cost of electricity generation at power plants equipped with CO2capture is expected to increase to 0.63-1.08 Yuan/kWh, slightly higher than the wind-generated energy cost at 0.5-0.6 Yuan/kWh, traditional electricity generation at 0.2-0.25 Yuan/kWh, and lower than solargenerated energy cost at 1Yuan/kWh [12]. CCS is estimated to increase the cost of electricity generation by approximately 60-80% at new coal combustion plants and by about 30-50% at new coal gasification plants. IPCC projects that CO2capture increases the generation cost of supercritical power plants, natural gas combined cycle (NGCC) power plants and IGCC power plants by 40-80%, 40-85% and 20-55%, respectively [1]. The specific capital cost and cost of electricity would increase by 50-80% and 40-80%, respectively, for a power plant that captures 90% of its CO2emissions, taking merely the CO2capture unit into consideration [47]. The cost would be even higher if the transport and storage units are further considered.

As for oxy-combustion system, the favorable benefit is that it avoids the need for a costly postcombustion CO2capture system. Instead, it requires an ASU to generate the relatively pure (95-99%) oxygen needed for combustion. Oxygen needed for an oxy-fuel combustion system roughly increases threefold than that for an IGCC power plant of comparable size, resulting in an expensive cost. As the temperature of combustion process with pure oxygen is much higher than that with air, oxy-fuel combustion also requires a large portion (roughly 70%) of the inert flue gas stream to be recycled back to the boiler in order to maintain a normal operating temperature [7]. Even though designs have been proposed to reduce or eliminate external recycle (e.g., slagging combustors, controlled staging of non-stoichiometric burners) for new oxy-fuel boilers, it still remains as a problem waiting to be solved. To avoid unacceptable content of oxygen and nitrogen in the flue gas, the system has to be carefully sealed as well.

2.2.2 High energy consumption

High energy consumption acts as a vital factor impeding CCS development. Power plants with CO2capture process will consume 30-40% more fuels than those without capture units [48]. For a coal-fired power plant, if ASU and CO2capture neutralize the efficiency of coal-fired power plants by 20-30%, compared with the CCS-free conditions, power plants with CO2capture facilities will consume more than 25% of fuel to produce the same amount of power. The cost would be even higher if the transport and storage units are further considered.

As for the oxy-fuel combustion system, it requires a more energy-consuming ASU to generate relatively pure oxygen. Besides, additional flue gas process is required to lower the operating temperature. With the aims to reduce the concentration of conventional air pollutants, meet pipeline CO2purity specifications and prevent the undesirable buildup of a substance in the flue gas recycle loop, more energy is consumed during the oxy-fuel combustion capture process [41-42].

2.2.3 Immaterial technology

For now, commercial post- and pre-combustion CO2capture have already been used in industrial applications to separate CO2from mixed gases, while oxy-fuel combustion capture is still under development and not yet deployed commercially. For oxy-fuel combustion, the fossil fuel is burned in a mixture of oxygen and recycled flue gas (RFG), and the flue gas consists of a large amount of water and CO2. Aside from the high costs for ASU, challenges still remain in the current design configurations and suitable heat-resistant materials in oxy-fuel combustion system.

2.2.4 Complexity of CCS

As a kind of complicated systems, CCS is comprised of several components (i.e. CO2capture, transport, storage and post-closure management). Thus it can only be successfully implemented through close cooperation between different industries and companies, in particular coal power and oil companies. However, a dim prospect for such operations may be anticipated due to a shortage of effective mechanisms. CCS researches in China mainly focus on pre-combustion and post-combustion, while studies on oxy-fuel combustion capture are largely neglected. As for the practical experience, only a few EOR and ECBM projects were carried out in China. In the course of transportation, the corrosive properties of CO2, interactions with water, heavy metals, particulates and other acid gases, infrastructure optimization, and choices of transportation tools are recognized as major issues to compromise the benefits. As for CO2storage, assessing storage capacity, modeling storage reservoirs, and designing new monitoring tools should also be undertaken in the next period.

2.2.5 Lack of regulations

To assure a commercial CCS project to be successful, both commercially viable CCS technology and a legal and regulatory framework shall be in place to provide warranty on matters relating to transport, storage, monitoring, and in particular the long-term liability. To address these issues, CCS regulations are being established in a number of countries. In the United States, CCS-specific legislation is being enforced on a state-by-state basis. In the European Union, the EU’s 2008 CCS Directive established a regulatory framework for the geological storage of CO2. Australia has also enacted comprehensive state and national CCS regulatory frameworks for CO2storage. Additionally, regulations are currently being prepared in Canada, Norway, and Japan [2]. For China, related research is still rather scarce.

2.3 Opportunities

2.3.1 Continued Consumption of Fossil Fuels

The Opening Reform since 1980 has directly contributed to a tremendous economic growth, which has led to an unprecedented demand for energy to sustain China’s transition to urbanization and industrialization. This growth is projected to continue driving surging energy consumption in China for several dec-ades, supplied by domestic resources as well as increasing imports from abroad. According to IEA, fossil fuel will maintain its dominance in energy supply for over 50% of global energy supply in the next few decades even though China achieved all of its proposed renewable energy and energy conservation targets [3, 39]. As a verified technology that can directly decouple CO2emissions from stationary fossil fuel sources, CCS could be of great significance for China in reducing emissions from carbon intensive sources. The soaring increase of coal consumption deriving from economic growth is an important factor that necessitates CCS deployment in China.

2.3.2 Pressure of climate change

Climate change is commonly taken as a global challenge in recognition of the threat to long-term human and ecosystem development. With 5.6 billion tons of CO2emissions in 2006 (20% of global emissions), China’s total emissions surpassed the BRIC countries (India, Russia, South Africa, and Brazil), and overtook the United States to be the world’s largest CO2emitter in 2007 [49]. Under such circumstance, China has established a national target aiming at slashing carbon intensity (CO2emissions per unit of GDP) by 40-45% in 2020 from 2005 levels. The central government of China considers energy-saving and the reduction of waste gas emissions as the most substantial objective of the next National Five-Year Plan. Even though China has no obligation to cut down CO2emissions under the Kyoto Protocol, as the largest CO2emitter, reducing CO2emissions is a global ambition for China [50]. In this situation, each method for CO2control should be paid due attention.

2.3.3 The CCS policy in China

The Chinese government has released a series of policies related to CCS, constituting the policy framework of CCS technology policy in China. On February 9, 2006, the National Medium- and Long-term Science and Technology Plan (2006-2020) published by State Council proposed “developing clean and CO2near-zero emission fossil fuel development and utilization technologies” in the field of advanced energy technologies. On June 4, 2007, China National Plan for Coping with Climate Change published by the National Development and Reform Commission (NDRC) put forward that developing CO2capture and utilization and carbon storage technologies shall be underlined; On June 14, 2007, a sectoral joint publishment “China Science and Technology Initiatives to Address Climate Change” put “CO2trapping and utilization, storage technologies" as the key task; On October 29, 2008, in China’s Policies and Actions for Addressing Climate Change, State News Office pointed out that “China is set to focus on technology for mitigating greenhouse gas emissions, including CO2capture, utilization and storage technologies”. On July 4, 2011, the National “Twelve-Five” Science and Technology Development Plan offered to develop the CCUS technology in “energy saving and environmental protection industries” as well as“tackling climate change”.

2.3.4 Vast low cost opportunities

Vast cost-effective opportunities for CCS deployment currently exist in China. With a steady economic growth rate, China's economic growth rate retains around 8% in recent years, much higher than that of developed countries’ 3-5%. Besides, China possesses the biggest coal chemical industry in the world, consuming 127 Mt coal and emitting more than 200 Mt CO2in 2008 [51]. Due to technical requirements, most coal chemical factories produce streams of highly concentrated CO2(480 vol %) that is much easier to capture. This provides China with potential opportunities to capture CO2at an extremely low cost. Moreover, China has a large number of low-permeability oil fields, which are theoretically fit for EOR, and the total potential for incremental oil recovery lies between 2-3 Gt, providing China with a similarly large number of low cost, or even negative cost (i.e. profitable) opportunities for CO2storage [52].

2.3.5 International collaboration

Currently, strong collaborative agreements on CCS R&D are quite active between China and the other countries that would like to see the emergence of CCS. Many collaborative research programs are already in operation or have been completed, including the China-EUCCS collaborative research projectsCOACH, STRA CO2, MOVECBM, China-UK project NZEC, China-Australia project CAGS, China-America projects APP Tsinghua-WRICCS Guidelines for China, CERC, etc., which is beneficial for helping China accumulate knowledge on CCS technology [48].

International cooperation will not only reduce the risk of CCS development, but also help lower CCS costs. Aside from the CO2reduction benefits, China is also offered an opportunity to occupy the giant global CCS market. As previously noted, CCS is still in the demonstration stage. If China can seize the opportunity and have a firm grasp of CCS technologies before other countries, it will attain a competitive advantage and might be able to occupy a large portion of the global market for CCS technologies and services.

2.4 Constraints

2.4.1 OtherCO2reduction technologies

If other CO2abatement technologies such as renewable energy and clean coal technology can lean forward significantly in terms of capability and cost in the future, it would be unnecessary to deploy CCS in a large scale. The balances between CCS and the other technologies should be given due consideration [47].

Even though CCS costs (about $ 75-115 for 1 ton CO2captured) exhibits a prioritized competence over solar energy, the other renewable energy systems still possess strong competitiveness. Aiming at constructing large-scale power base in wind-rich areas, China’s wind power has experienced a rapid growth during the last six years. In 2012, China’s total wind power capacity reached up to 50.26 GW, making China the largest wind power country [53]. A rapid development for biomass power industry is also witnessed in China. By the end of 2020, the installed biomass power generating capacity will increase to 30,000 MW, accounting for 4% of primary energy consumption [54]. As the most promising energy, nuclear energy makes up 4% of all the energy produced. This figure will reach 5% in 2010 and nearly 10% in 2020, equivalent of 40 million KW. In terms of energy security and environmental protection, renewable energy will be the optimum candidate for energy strategy in China. Their development will greatly impact on the deployment of CCS [12].

Clean coal technology is taken as another promising technology in the future. From 2002 to 2007, there were 46 projects related to clean coal technology; in contrast, only nine projects were related to CCS in the same period in China [55]. In terms of experience, some demonstration projects for power plants with clean coal technology are currently in sound operation, whereas experience for CCS is very limited, and some important data covering the cost of capture and injection, qualified geological sites, have not been extensively studied.

2.4.2 Technical bottleneck

With regard to the technological aspect, although some knowledge and experiences have been gained through ongoing researches and demonstrations, CCS implementation is still far from being deployed on an industrial scale. As for oxy-fuel combustion, a great challenge is that current design configurations and materials are unable to operate at a high temperature range. Besides, reducing the total costs and energy consumption for generating the relatively pure (95-99%) oxygen is demanded as well.

2.4.3 Uncertain geography data

Though it is projected that China is endowed with immense capacity for CO2storage, some detailed geological investigations, though, have indicated that achievable capacity may be lower due to complex geological structures at the local scale. More geological investigations and characterization works are needed to be done before a final conclusion on China’s storage potential can be drawn. Besides, a recent study suggests that the storage capacity for CO2in China is 21 billion t, equal to 4 times the 5.7 billion t annual emissions in China, thus the CO2storage capacity is insufficient [56].

2.4.4High risk and public acceptance

CCS projects can greatly threaten the safety and health of local residents, especially for a denselypopulated country like China [57]. CO2storage on a large scale may probably cause geological transformations such as earthquakes. If CO2concentration rises by 5-10%, it will be harmful to human life. Besides, CO2injection into the sea will have a certain chance to damage the marine ecosystems. Furthermore, CO2storage on shore or offshore is likely to be pretty harmful for the geological system (i.e., polluting the underground water).

CCS in developing countries is poorly understood by the general public. As a result, there appears to be a lack of public support for CCS compared with several other greenhouse gas mitigation options. With limited awareness and understanding, the deployment of CCS projects is likely to be violently opposed by domestic citizens, or even abolished, by local governments just as the situation in Germany, the United States, and the Nether- lands [58-60].

2.4.5Unclear national plan

Though acknowledging the potential significance of CCS for CO2deduction, the Chinese government has not released a clear blueprint, prepared a detailed development schedule, or established a financing mechanism for CCS deployment. As a result, related companies cannot get granted permits or economic support in deploying CCS. Without support from the Chinese government, it will be extremely difficult to deploy CCS in a large scale. Due to the lack of resolution on CCS addressed in the points above, it leaves great uncertainties for the future development of CCS in China.

2.4.6Scarcity of talents

Additionally, experts specializing in CCS are limited in China, although the situation seems to be same for other countries.

3 Concluding remarks

CCS is a strategic technology option for China to reduce its CO2emission and help mitigate global climate change. However, the prospect for future CCS development in China is unclear, with a number of looming uncertainties. To promote the CCS deployment in China, especially based on the 35MWth national program supported oxy-fuel combustion demonstration project in construction, the analyses on strengths, weaknesses, opportunities and constraints on CCS deployment in China are conducted in detail.

In consideration of technology immaturity and lack of economic incentives for oxy-fuel combustion capture system, a technology roadmap for oxy-fuel combustion capture system in China can be presented. Current roadmaps for carbon capture technology commercialization and deployment envision will be generally available by 2020. At the same time, research organizations acknowledge that a sustained R&D effort will be required over the next decade to achieve that goal, especially for the processes that are still in the early stages of development. The current technical bottleneck in terms of O2 supply, CO2purity, and air leakage should be settled. The magnitude of future cost reductions is likely to depend on the pace of CCS technology deployment as well as on sustained R&D support. More geological investigations and characterization work are needed to be done before a final conclusion on China’s storage potential can be drawn. To connect the site between the capture and storage sites, an entire transportation network should be in place to serve as a supplement.

To gradually implement the roadmap designed above, several measures should be put into action. Costeffectiveness will require a substantial level of commercial deployment. Early-stage commercial demonstrations are demanded for oxy-fuel combustion system, through which researchers could better gain initial knowledge of design principles and system configurations. As for international cooperation, it is significant to treat the joint projects as a platform to strengthen exchanges and cooperation with foreign authorities. Various types of incentive programs can accelerate the deployment of CCS, thus significantly limiting CO2emissions emitted to the atmosphere. Meanwhile, a vigorous and sustained level of R&D,especially focus on the CO2separated and materials operated at a high temperature should be given adequate priority in oxy-fuel combustion system.

Acknowledgements

This work is supported by the open foundation of Hubei Key Laboratory of Industrial Fume & Dust Pollution Control (HBIK2013-03), the State Key Program for Basic Research (973 Program, grant no.

2013CB228102), the Natural Science Foundation of China (grant no. 51306067) and Scientific Research Program of Agriculture Public Welfare Profession of China (grant no. 201303095).

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†Corresponding author.

Email address: qyang@mail.hust.edu.cn; gqchen@pku.edu.cn (G.Q. Chen).

ISSN 2325-6192, eISSN 2325-6206/$- see front materials © 2013 L&H Scientific Publishing, LLC. All rights reserved.

10.5890/JEAM.2013.11.003

Accepted 4 November 2013

Available online 1 January 2014