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This paper reports the key findings and conclusions of a study that analyzes the financing of large-scale CO 2 Capture and Storage (CCS) demonstration projects worldwide. By looking across dozens of CCS demonstration projects that have been under development, both completed and cancelled, one can identify the ingredients necessary for success, as well as pitfalls to avoid. This paper summarizes how “successful” CCS demonstration projects were financed, reviews the largest government programs designed to help finance these projects, and reports on the lessons learned. [ABSTRACT FROM AUTHOR]

Oxyfuel combustion is one of the leading technologies considered for capturing CO 2 from power plants with CCS. This involves the process of burning the fuel with nearly pure oxygen instead of air. In order to control the flame temperature, some part of the flue gas are recycled back into the furnace/boiler. Since the publication of the Special Report on CO 2 Capture and Storage by the International Panel for Climate Change ( IPCC, 2005 ), the development of oxyfuel combustion technology has progressed significantly and could be considered at par in terms of technology maturity as compared to other leading CO 2 capture technologies. This paper presents an overview to the current state-of-the-art technology on the development of oxyfuel combustion applied to (a) PC and CFB coal fired power plants and (b) gas turbine based power plant. It should be noted that it is not the intention of this paper to provide a comprehensive review but to present what have been achieved in the past 10 years of RD&D efforts. For coal fired power plant using oxyfuel combustion, this paper primarily presents the different development aspects of the burners and boilers (combustion and heat transfer), emissions, operation of the plant (i.e. start-up and turndown) and its integration to the ASU and CPU. For gas turbine based power plant using oxyfuel combustion, the different GT cycles are described, looking at the different aspects in combustion, emissions, cycle efficiency and development of the turbomachineries. Also presented in this paper is a snapshot to what we have learned from the operation of the different large-scale pilot plants and development of large scale demonstration projects worldwide. The paper concludes by presenting the potential of this technology and highlighting the importance of realizing large scale demonstration plant as a necessary step to achieve its ultimate goal of technology commercialization. [ABSTRACT FROM AUTHOR]

An alternative CO 2 curing method for precast concrete products has been proposed in order to achieve rapid strength development at early age, as well as to capture and store greenhouse gas (CO 2 ). In this paper, an experimental study for the development of a maturity approach is presented to estimate the strength development of carbonated concrete blocks. In order to promote the use of industrial flue gas containing CO 2 , a flow-through CO 2 curing regime at ambient pressure and temperature was employed using different atmospheric conditions, such as various CO 2 concentrations, RH values and gas flow rates. The experimental results showed that the compressive strength or maturity of the carbonated concrete blocks was affected by two factors: accelerated cement hydration and carbonation extent. A high CO 2 concentration, a fast gas flow rate and a moderate relative humidity were essential for enhancing the maturity and the strength development. The developed model based on the maturity approach may accurately predict the strength development of the carbonated concrete blocks. [ABSTRACT FROM AUTHOR]

In this paper, techno-economic analysis of direct coal biomass to liquids (CBTL) plants is performed in Aspen Process Economic Analyzer (APEA) using high fidelity process models developed in Aspen Plus for four different configurations of direct CBTL plants. Results from the economic model are validated with the data in the open literature, if available. Sensitivity studies are conducted to evaluate the impacts of key investment parameters, design parameters, and potential government-subsidized credits on the main economic measures including net present value (NPV), internal rate of return (IRR), break-even oil price (BEOP) and equivalent oil price (EOP). Using the North America 2015 pricing basis in APEA, this study shows that the BEOP of direct CBTL processes ranges from $56.9/bbl to $80.5/bbl for large scale (50,000 bbl/day) plants and from $77.3/bbl to $97.5/bbl for small scale (10,000 bbl/day) plants. It is observed that integrating a carbon capture and storage (CCS) unit to the direct CBTL process can increase the BEOP by about 10%, while utilization of the cheap and abundant shale gas (especially in the continental US) can make the direct liquefaction processes considerably more attractive than the indirect CBTL processes. [ABSTRACT FROM AUTHOR]

India's developmental needs in the near and long-term future will be strongly interlinked with the need to provide steady electricity to its cities and villages. The current fleet of Electricity Generating Units (EGUs) in India is mostly coal-based. These coal-fired power plants lead to a substantial amount of CO 2 emissions. Due to international climate obligations, there might be a need to limit the amount of unmitigated CO 2 emissions being emitted into the atmosphere. Mitigation of such emissions at coal-fired power plants offers an easily controllable way of reducing such emissions. The mechanisms to reduce emissions in coal-fired power plants may be through installation of super-critical units, repowering the plant with Integrated Gasification Combined Cycle (IGCC) or with use of coal blended with biomass. More radical emission cuts may be obtained by retrofitting the existing plants with CO 2 Capture and Storage (CCS), a technology with the ability to reduce the emissions by 80-85% of the current emissions levels. This paper begins with a brief insight into some of the mechanisms to cause emission reductions in coal-fired power plants. It focuses mainly of how retrofitting the power plants with CCS technology will affect the techno-economic of the plant. Three types of plants will be analyzed, viz, Low performance, medium performance and high performance; the categorization being based on the current Indian fleet of EGUs. We analyze five pathways for mitigation, with two focusing on efficiency improvements and three on CCS technology. The results show that overall cost of avoidance for CCS ranges from US$ 59.54 to US$ 85.41 per tonne of CO 2 . There is a strong incentive for repowering of old plants to supercritical units and their subsequent retrofitting with CO 2 capture systems than direct retrofitting of low performance plants. [ABSTRACT FROM AUTHOR]

This paper presents a thorough thermodynamic analysis and optimization of the NET Power cycle (also called Allam cycle), a natural-gas-fired oxy-combustion cycle featuring nearly 100% CO 2 capture level, very high net electric efficiency, and potentially near-zero emissions level. The main goals of this study are the systematic optimization of the cycle for the maximum efficiency, and the quantification of the effects of the modelling assumptions and equipment performance on the optimal cycle variables and efficiency. An Aspen Plus flow-sheet featuring accurate first-principle models of the main equipment units (including cooled turbine) and fluid properties (equation of state) has been developed. The influence of the cycle variables on the thermodynamic performance of the cycle is first assessed by means of sensitivity analyses. Then, the cycle variables, which maximize the net electric efficiency, are determined with PGS-COM, a black-box numerical optimization algorithm, linked to the simulation software. The corresponding maximum cycle efficiency is equal to 54.80% (with 100% CO 2 capture), confirming the outstanding performance of the NET Power cycle. Moreover, the optimization indicates the existence of promising combinations of the cycle variables which lead to reduced component costs (due to the lower operating pressures and temperatures) of the most critical components, without considerably affecting the net electric efficiency. The analysis also indicates that the cooling medium temperature, the power consumption of the air separation unit, the effectiveness of the regenerator and the effectiveness of the turbine cooling system are the main factors influencing the cycle efficiency. [ABSTRACT FROM AUTHOR]

The consumption of non-renewable primary energy resources results in their depletion, which is becoming absolutely crucial for the sustainable development of humankind. The production of electricity based on burning fossil fuels involves harmful emissions. Thus, the additional consumption of primary energy is required in order to make up for the environmental impact. The of that consumption of primary exergy per unit of useful products is called the index of TEC (thermoecological cost). When the whole life cycle is considered, we have to do with the LC TEC (life-cycle thermoecological cost). The paper presents the concept of a life cycle assessment based on the thermoecological cost implemented in an integrated OFC (oxy-fuel combustion) power plant with CO 2 capture, transport and storage. A mathematical model evaluating the LC TEC was applied and the example utilised Polish conditions. The obtained value of the LC TEC of the analyzed CCS (Carbon capture and storage) system (with 90% CO 2 emission reduction) is about 22% higher than the average value for polish coal-fired power plants (without CCS). The results of sensitivity analysis concerning LC TEC allow to conclude that the operation phase dominates (over 99.5%), thus the construction, repairs and decommissioning phases for CCS systems could be neglected in further studies concerning the depletion of non-renewable natural resources. [ABSTRACT FROM AUTHOR]

Chemical-looping combustion is an interesting technique that makes it possible to integrate power generation from fuels combustion and sequestration of carbon dioxide without energy penalty. In addition, the combustion chemical reaction occurs with a lower irreversibility compared to a conventional combustion, leading to attain a somewhat higher overall thermal efficiency in gas turbine systems. This paper provides results about the energetic performance of an integrated gasification combined cycle power plant based on chemical-looping combustion of synthesis gas. A real understanding of the behavior of this concept of power plant implies a complete thermodynamic analysis, involving several interrelated aspects as the integration of energy flows between the gasifier and the combined cycle, the restrictions in relation with heat balances and chemical equilibrium in reactors and the performance of the gas turbines and the downstream steam cycle. An accurate thermodynamic modeling is required for the optimization of several design parameters. Simulations to evaluate the energetic efficiency of this chemical-looping-combustion based power plant under diverse working conditions have been carried out, and a comparison with a conventional integrated gasification power plant with precombustion capture of carbon dioxide has been made. Two different synthesis gas compositions have been tried to check its influence on the results. The energy saved in carbon capture and storage is found to be significant and even notable, inducing an improvement of the overall power plant thermal efficiency of around 7% in some cases. [ABSTRACT FROM AUTHOR]

This paper summarizes expert opinions regarding crucial factors that may influence Vietnam’s future use of carbon capture and storage (CCS) based on face-to-face interviews in December 2013 with 16 CCS-related experts from the Vietnamese government, research institutes, universities and the energy industrial sector. This study finds that financial incentives and climate policy are the most important factors for the development of CCS technologies in Vietnam in the next two decades. Financial incentives involve direct subsidies from the government, such as tax exemptions for land use and the importation of CCS-related equipment. In addition, all the experts agree that international financial support is important to initiate a large deployment of CCS technologies in Vietnam by implementing demonstrative/pilot projects to prove CCS’s working efficiency. [ABSTRACT FROM AUTHOR]

The net greenhouse gases (GHG) emissions of conversional Fischer Tropsch (FT) synthetic fuels derived from coal are about double of those from petroleum fuels. Adding moderate amounts of biomass to coal can substantially reduce the carbon footprint of the indirect fuel production plant. The indirect coal–biomass to liquids (CBTL) technology with CO 2 capture and storage (CCS) is more environmental friendly than the conventional coal to liquids (CTL) processes. This paper focuses on the selection of CCS technologies and obtaining their optimal operating conditions for a CBTL plant. A detailed process model is developed in Aspen Plus V7.3.2 for this purpose. In this plant, syngas is produced in the biomass/coal-fed co-gasifier. Then, a sour water gas shift (WGS) reactor converts a portion of the CO in the syngas to CO 2 to obtain the desired H 2 /CO ratio in the syngas feed to the FT unit. Substantial amount of CO 2 is captured before the FT reactor by using a dual-stage, selective physical solvent-based process. In the FT unit, the Fe-based catalyst is used in the low temperature FT (LTFT) slurry reactor to convert syngas to hydrocarbons. For selection of the post-FT CO 2 capture technology, three candidate technologies – Selexol, MEA and MDEA/PZ, are evaluated. The results show that the MDEA/PZ technology with intercooling has the lowest overall penalty. Impacts of two key design variables, H 2 /CO ratio at the inlet of the FT unit and biomass/coal ratio of the feedstock, on the product yield and utility consumptions are investigated. [ABSTRACT FROM AUTHOR]

Chemical-looping combustion for power generation has significant advantages over conventional combustion. Mainly, it allows an integration of CO 2 capture in the power plant without energy penalty; secondly, a less exergy destruction in the combustion chemical transformation is achieved, leading to a greater overall thermal efficiency. Most efforts have been devoted to systems based on methane as a fuel, although other systems for alternative fuels have can be proposed. This paper focus on the study of the energetic performance of this concept of combustion in a gas turbine combined cycle when synthesis gas is used as fuel. After optimization of some thermodynamic parameters of the cycle, the power plant performance is evaluated under diverse working conditions and compared to a conventional gas turbine system. Energy savings related with CO 2 capture and storage have been quantified. The overall efficiency increase is found to be significant, reaching values of around 5% (even more in some cases). In order to analyze the influence of syngas composition on the results, different H 2 -content fuels are considered. In a context of real urgency to reduce green house gas emissions, this work is intended to contribute to the conceptual development of highly efficient alternative power generation systems. [ABSTRACT FROM AUTHOR]