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Abstract: The Kansai Electric Power Co., Inc. (KEPCO) has developed energy efficient chemical absorbents and economical processes which aim to reduce the cost of CO2 capture, in collaboration with Mitsubishi Heavy Industries, Ltd. (MHI). Together the companies have been developing and critically testing high efficiency, economical absorbents according to the latest absorbent development procedures and process simulation for CO2 capture processes. This work has been ongoing since 1991, using several Japan based R&D facilities and a pilot plant, used to verify improvements, located at Nanko Power Station in Osaka, Japan. Following significant testing of a range of absorbents in the mid 1990s, KS-1TM, KS-2 and KS-3 were developed. Based on subsequent rigorous evaluation of the three solvents, KS-1TM was selected for commercialization because of its overall technical and economical merits. During long-term pilot plant testing, the improved absorbents demonstrated superior performance in relation to the regeneration energy requirements leading to the following results: 2.94 MJlkg- CO2 in combination with KS-1TM” and the Kansai Mitsubishi Carbon Dioxide Recovery (KM-CDR ProcessTM) commercial process. In addition, practical, commercially applicable improved absorbent properties such as low corrosiveness and low solvent consumption were also confirmed. KEPCO and MHI continue development work in this area and the current status is summarized as follows: The highly successful R&D phase has led to the commercial deployment of CO2 capture technology and seven (7) commercial CO2 capture plants are currently under operation, with a maximum CO2 capture capacity of 450 metric tons per day (tpd). These commercial plants are deployed in the chemical and fertilizer industry, where the operational performance is assisting in the improved development of R&D concepts. Two (2) further commercial plants are under construction, with commissioning expected in Q3 2010. For further cost reductions in relation to CO2 capture, recent work has focused on developing new energy efficient chemical absorbents and processes. Following modifications to the Nanko CO2 capture pilot plant a new “Energy Saving Process”, was developed, which leads to a greater than 10% steam consumption reduction over the MHI conventional process using KS-1TM absorbent. Additionally the same reduced steam consumption was recorded for tests using the KS-1TM absorbent. A thermal energy requirement of less than 2.5 MJ/kg- CO2 in combination with KS-1TM and the “New Energy Efficient Process” has been confirmed under the optimum operation condition of the CO2 capture process. In addition to select new absorbents which feature the best profile and fit to the actual operating condition, KEPCO and MHI have intensively evaluated vapor-liquid equilibrium (VLE) and reaction kinetics for a range of newly developed absorbents and their performance is presented in this paper. The above data was obtained using the Nanko CO2 capture pilot plant which operates under a natural gas fired boiler condition and we expect that the thermal energy requirement of coal fired boiler flue gas (with greater CO2 concentration condition) will be further reduced. KEPCO and MHI are continuing pilot tests for the “Energy Saving Process”, leading to the application of this new process in commercial CO2 capture plant design. This paper introduces and presents the current status of the KEPCO & MHI CO2 capture technology and concepts for future energy reduction improvements. The paper will also include test results in relation to newly developed absorbents, and the “New Energy Efficient Process”, which have enhanced the performance and reduced the associated energy penalty of the CO2 capture process. KEPCO and MHI are continuing the development of efficient absorbents and optimized processes, thus helping to facilitate the future wide scale deployment of CO2 capture technology as an effective counter measure against global warming. [Copyright &y& Elsevier]

Abstract: This paper presents the results of ASPEN simulations of a carbon-dioxide (CO2) removal and recovery plant that captures CO2 from a 500 MWe (net) conventional coal-fired power plant flue gas stream. At a constant CO2 recovery rate of 86.5% by weight, the performance of aqueous ammonia solution as an alternative to various aqueous amino solvents (MEA, AMP and MDEA) is compared in terms of the process scenarios, solvent loadings and overall energy consumption. The overall mass transfer co-efficient and CO2 loading data generated for aqueous ammonia solutions using a laboratory scale wetted wall gas-liquid contactor are also presented. The ASPEN simulation results in conjunction with the laboratory data show, that capturing CO2 from coal-fired power plant flue gas, using aqueous ammonia solvent, will require ammonia concentration no more than 5% by weight and absorber temperature 10 ∘C or lower, if the vapor phase ammonia losses are to be contained and the precipitation of ammonium bi-carbonate in the absorber is to be avoided. Under such an operating scenario, the aqueous ammonia based CO2 capture process has overall energy requirement comparable to the conventional 30% by weight aqueous MEA based process. The ASPEN results further show that 30% by weight AMP based process has the lowest overall energy requirement among the solvents considered in this paper. [Copyright &y& Elsevier]

Abstract: The application of Carbon Capture and Storage (CCS) in the power industry is important for reducing man-made CO2 emissions. This paper proposes new ways to categorize the options for mitigation of man-made CO2 emissions and CO2 capture. A detailed description on the ways to capture, transport and store CO2 has been presented. The power penalties and cost can be big challenges to apply CCS to the power industry, while a lot of opportunities exist, such as value added CO2 storage, industrial utilization of CO2 and the development of the carbon trade market. [Copyright &y& Elsevier]

Abstract: CO2 emission from combustion flue gases has become the primary factor in global warming. Chemical methods of absorbing CO2 from combustion flue gases have been widely used in engineering, because of its simple and convenient operation, high absorption efficiency and economic value. This paper analyses the domestic and foreign researches on chemical methods of absorbing CO2 from combustion flue gases, and summaries the effect of the reactors structure, absorbent type and operating conditions on absorption efficiency. This article also forecasts present developmental directions, and expects to have a certain reference to later research and development. [Copyright &y& Elsevier]

Abstract: This paper describes an investigation for multi-stage systems used in coal-fired power plant. The whole work was divided into two steps: energetic and economic analyses. In the first step: on the basis of a serial concept, through varying the position of compressors and vacuum pumps, recycling the retentate of the 2nd membrane to the feed side of the 1st membrane, a cascade variant was developed and analysed. In the second step: an economic model was developed to calculate the capture cost of the cascade system. The total cost is composed of investment cost, operation and maintenance (O&M) cost and electricity cost. A correlation between the membrane parameters: selectivity & permeability and capture performance: energy consumption & capture cost was built up. Using Polyactive® membrane developed by GKSS with CO2 permeance of 3 Nm3/m2hbar and CO2/N2 selectivity of 50, under the separation target of 70% degree of CO2 separation and 95 mol% CO2 purity, adopting the cascade membrane system in the 600 MW NRW-reference power plant, the specific energy consumption including CO2 compression (110 bar, 30 °C) is 256 kWh/tseparatedCO2 with 6.4%-pts efficiency loss. The capture cost is 31 euro/tseparatedCO2 , which could be a promising solution as a retrofit for the existing power plants. [Copyright &y& Elsevier]

Abstract: An energy network with polygeneration system and CCS suitable for China was proposed in our previous work in consideration of low-cost CCS and energy providing safety. In this paper, based on life-cycle analysis, the role of the Energy Network has been investigated at the national level. Results show that with the import dependency of oil controlled in the range of 40%–60% during 2020 to 2030, up to 22% of the total capacity of coal fired supercritical power plants may be replaced by hundreds of new polygeneration plants for electricity and alternative fuels. When the oil import dependency will be kept from 40% to 60%, the Energy Network can save 20%–30% of energy and cut down 30%–40% of total costs every year compared to the present method with coal fired supercritical power plants and traditional alternative fuel plants with CO2 capture. And the Energy Network can capture more than 0.1 billion tons of CO2 with high concentration over 98% each year. Moreover, from the aspect of CCS, this Energy Network can realize as low as 15$/t of total CCS cost due to the quite low energy penalties of CO2 capture in the polygeneration systems and the combination of CO2 sources and storage sites. The new Energy Network has realized the proper combination of energy utilization and CO2 capture and storage according to the unique state of China. It is suitable for China and may play an important role in CCS in the future. [Copyright &y& Elsevier]

Abstract: Energy sources such as oil, natural gas, and coal currently account for around 80% of the world’s primary energy consumption. Despite significant investments in renewable energy and energy efficiency, that Canada and others are making, the International Energy Agency (IEA) has forecast that as the global economy continues to grow, fossil fuels will continue to dominate the world’s energy supply for decades. Reconciling the world’s ongoing reliance on fossil fuels with the need to reduce greenhouse gas (GHG) emissions is then one of our greatest challenges. Canada is taking this challenge seriously with climate change policies that include enhancing our global leadership in advancing one of the most promising technologies for reducing GHG emissions from fossil fuel use: Carbon capture and storage (CCS). CCS is only one of several technologies that must be deployed and is not a ‘silver-bullet’ for meeting Canada’s target of reducing its GHG emissions by 17% from 2005 levels by 2020. Yet, CCS is one of the only technologies currently available for making emissions reductions from large-scale fossil fuel usage–and, thus, will be a critical component of the technology puzzle for Canada to meet its emissions reduction objectives. Canada has a number of key sectors where the deployment of CCS is needed and there are opportunities to advance the technology. These include coal-fired electricity plants, the oil sands, and natural gas processing (e.g. from the new development of shale gas) -though the opportunity and demand for advancing CCS technology also exists in other sectors such as chemicals, fertilizer, steel making, and cement. Federal and provincial governments in Canada are making substantial investments in CCS, committing upwards of $3 billion in public funding towards seven large-scale fully-integrated CCS demonstration projects. The federal ecoENERGY Technology Initiative announced $151 million for the initial engineering and/or pilot stages of seven potential demonstration projects in 2008. The 2009 federal budget created Clean Energy Fund, which included $610 million for CCS demonstrations. The Provinces of Alberta, Saskatchewan, and British Columbia have also committed funding for demonstrations, in particular $2 billion by Alberta. This public funding will leverage additional investment from industry, for projects that will each capture and store on the order of 1 million tonnes of CO2 per year, coming on-line starting in 2015 or sooner. This paper will provide an overview of Canada’s actions on advancing CCS deployment, with a focus on the CCS demonstration program and current R&D activities in Canada. [Copyright &y& Elsevier]

Abstract: The oxy-fuel combustion CO2 capture route and post-combustion CO2 capture route involve different energy consumption rates and subsequent environmental impacts. The holistic perspective offered by Life Cycle Assessment (LCA) can help decision makers to compare alternative CO2 capture and storage technologies in a life cycle perspective. This paper, at first, introduces the principles of the dynamic LCA model developed for oxy-fuel combustion and post-combustion power generation with CO2 capture, transport and injection processes. Next, a comparative life cycle assessment of alternative CO2 capture technologies is presented. Results show that, at life-cycle level, the post-combustion and oxy-fuel combustion CCS cases can reduce the life-cycle Global Warming Potential (GWP) by 78.8% and 80.0% respectively compared to conventional power plant without CCS. Other environmental impacts, such as Ecotoxicity, Human toxicity and Acidification, vary significantly with the different CO2 capture routes employed. Finally, by comparing the results obtained with the most recent LCA studies of post-combustion power generation with CO2 capture and storage, it is shown that the plant level, gate-to-gate studies provide significantly variable results and generally overestimate life cycle environmental impacts. [Copyright &y& Elsevier]

Abstract: This paper presents the results of careful considerations on the surface facilities at one of the most promising CCS (Carbon dioxide Capture and Storage) candidate sites in Japan in regards to process, economy and energy consumption. This site has been selected to demonstrate the feasibility of CCS total system in which CO2 is captured from natural gas processing plants, transported to the injection site (100 km away from the plants), and then stored in the saline aquifers underneath the seabed of the Japan Sea. Four technical issues have been reviewed for the surface facilities, namely CO2 transportation, removal of impurities in the CO2 gas, the liquefied CO2 heater models and the shaft seal system for CO2 pumps. As for the CO2 transportation method, tanker trucks transportation is selected compared to pipelines because of the merits in a construction period, economy, and local citizen’s understanding and acceptance which are crucial for the realization of the project. Concerning process building, removal of impurities contained in the CO2 gas has been considered first. CO2 gas separated from natural gas contains hydrogen sulfide, mercury, and BTX in addition to water. These impurities must be eliminated prior to liquefaction of CO2 because they could interfere with the process as well as for environmental considerations. The adsorption method is found to be effective for removing all these impurities. However, it is also found that adsorbent consumption rate depends largely on the process sequence with which the impurities are eliminated. After reviewing the results, it is found that the most economical sequence to eliminate these impurities is in the order of mercury, hydrogen sulfide, BTX, then water. Liquefied CO2 heater models have been considered to reduce CO2 emission. After transportation to the injection site, the liquefied CO2 is pressurized and heated from −10 °C to a super critical state of 40 °C in order to avoid phase transition inside the injection tube. Using a heat pump to utilize the heat in the air to improve the energy efficiency, CO2 emission is substantially reduced by approximately 70% compared to the conventional method using hot water from a boiler that uses heavy fuel oil. A centrifugal pump will be selected for CO2 pumps because it can handle large volumes. An effective shaft seal system is the tandem formation using vapor-liquid seal and dry gas seal for the first and the second stages respectively. However, since we have limited experience of this formation at CO2 pumps in Japan, it is identified as a critical item in the demonstration project. [Copyright &y& Elsevier]

Abstract: To fulfill the energy demand now and in the next decades, coal-fired power plants will be an essential part of the portfolio of power plants that supply electricity cheaply and in a reliable way. The specific CO2 emissions of these plants can be reduced by increasing the efficiency. For that reason KEMA did optimize the steam water cycle of ultra super critical (USC) coal-fired power plants within the EOS program. The improvements are based on the application of the so-called Master Cycle, and on the application of higher steam temperatures. In the Master Cycle cold reheat steam is used in an extra turbine and with steam extraction of this turbine feed water preheating is realized with reduced exergy losses. The turbine is called a tuning turbine reflecting the improved possibilities to tune and optimize the steam cycle with the new coupling where the regenerative heater train and the re-heaters have been decoupled. The Master Cycle is proposed by Dong Energy . The first approach deals with the USC technology with a steam temperature of 600 °C and reheat temperatures of 620 °C. This technology is available at the moment and is applied in new built coal-fired power plants. The second approach deals with the USC technology with a steam temperature of 700 °C and reheat temperature of 720 °C. The expectation is that this technology can be applied around 2025 with the same availability as the USC units with 600 °C. The thermodynamic analyzes are carried out with KEMA’s flow sheeting package SPENCE®. In all considered cases the thermal input was 2400 MWth. In case of the application of the Master Cycle a second reheat is introduced. Results will be discussed and presented in tables, t-s diagrams and h-p diagrams. Improvement of efficiency of coal fired power station technology can reduce the amount of CO2 emitted significantly. This paper shows that with current available technology and improvements an additional emission reduction of almost 10% can be realised by applying the USC 700 + MC. Compared to the world wide average an emission reduction of 66% can be achieved without CCS. In the continuation of the analysis post combustion technology will be integrated in the concept to analyze possible additional benefits of the master cycle with respect to steam supply for the regeneration of the solvents. [Copyright &y& Elsevier]

Abstract: This paper explores the resource intensity and major cost elements of direct air capture of carbon dioxide. The levelized cost of carbon removal is calculated as the sum of costs resulting from interdependent capture devices, energy supplies, water supplies and sequestration resources. The analysis considers “generic” air capture technology characterized only by its energy use, capture footprint, and water use. Capital costs dominate the analysis, followed by energy efficiency. Four dedicated energy resources are considered: Wind, enhanced geothermal, natural gas combined cycle (NGCC), and NGCC with 90% carbon capture. Nearly carbon-free energy is critical to keeping overall cost of carbon mitigation low. The analysis shows that high second law capture efficiencies (on the order of 10%) and relatively inexpensive capture devices (on the order $0.5 M for an individual device capturing one tonne CO2/day) must be achieved if the cost of air capture is to approach $300/tonne- CO2. Reaching those goals is likely to require substantial research into the kinetics and thermodynamics of capture chemistry which, respectively, keep the capital and energy costs as low as possible. [Copyright &y& Elsevier]

Abstract: To make the deployment of carbon capture possible, it is highly needed to develop original solutions that induce low energy penalty and that are easy to operate. This paper aims at presenting the DMX™ process developed at IFP Energies nouvelles based on special solvents which are characterized by the formation of two immiscible phases for given temperature and CO2 loading conditions. The concept of demixtion is briefly described in terms of physico-chemical properties, its interest and all required steps for appropriate process development are discussed. The corresponding process is presented and a technico-economic analysis is given. It is shown than one can reach a reboiler duty as low as 2.1 GJ/t CO2 which is significantly lower than the 3.7 GJ/t CO2 of the 30wt.% MEA reference process. It is also discussed that the energy consumption at reboiler cannot be the only parameter to consider for comparison with other processes and some further information about the DMX™ process are given. Operational issues are particularly discussed. In that sense, the performances of the DMX-1TM solvent in terms of degradation and corrosion are shown. Similarly a particular focus is made on the liquid/liquid separation which is a key aspect of the DMX™ process. [Copyright &y& Elsevier]

Abstract: TOTAL Exploration and Production is involved in a number of production and/or processing projects such as Heavy oil, Oil sands and LNG which require substantial amounts of energy (heat and power). Alongside this, sustainable development of energy resources is a prime target for the Total group, which strives constantly to reduce the GHG intensity of its production activities. On new projects and for major plant modifications, this is achieved by optimizing energy efficiency and preventing continuous flaring of produced gas, which is marketed or re-injected instead. On current producing installations, a continuous improvement process to address flaring reduction and energy efficiency is on-going. However in view of the coming development challenges, Total is further considering the development of facilities with a limited GHG footprint, by the means of emissions reduction through carbon capture and sequestration. Designing capture-ready installations is the first step on this path. It is a challenging task owing to the evolving nature of available technology, the high energy demand and correlative emissions of carbon and the unusual specific constraints in dedicated Oil and Gas energy plants. This paper presents our experience in this learning process applied to the oil & gas industrial environment. With the collaboration of Technip, Total initiated a study on the integration of carbon-capture solutions within cogeneration plants. On the strength of its in-house experience of oxy-combustion and acid gas removal, of transport and re-injection of acid gases, Total considered both oxy-combustion and post-combustion as promising technologies. The objective of the study was to assess the potential of each technology to tackle carbon capture on the two main types of thermo-mechanic converters present in a cogeneration plant: turbines and boilers, as well as evaluate the constraints. Alternative cogeneration plant concepts, with or without combined cycle were considered, to challenge further the impact of capture on cogeneration design. The actual operating conditions of a typical cogeneration plant burning clean natural gas, particularly its flue gas emissions, compatible with the target project’s constraints, were proposed as the design basis for capture systems of various scales. The requirement to keep to simple capture concepts was critical in view of the challenging economic environment of carbon capture, the evolving technology and the probable tightening of emission-reduction targets. Due to the uncertainties as to the final fate of the carbon dioxide, EOR or/and geo-storage, nearby or distant, in depleted fields or saline aquifers, being considered, several CO2 conditioning process options were defined. The integration of capture-ready building blocks within the plants was a significant step in the design process for alternative cogeneration plants, and enabled the synergies and constraints of operating the capture systems to be identified. The key risk items were highlighted, offering insight into the expected roadmap of the capture technology development. The results of this work compare the main features of the oxy-combustion and post-combustion CO2 capture technologies for steam-boiler and/or gas-turbine effluents and flag up some essential local constraints affecting the performance of the various capture-ready cogeneration schemes. [Copyright &y& Elsevier]

Abstract: This paper presents the methodology and the preliminary results of a techno-economic assessment of CCS implementation on the iron and steel sector. The results show that for the short-mid term, a CO2 avoidance cost of less than 50 € /tonne at a CO2 avoidance rate of around 50% are possible by converting the conventional blast furnace (BF) to Top Gas Recycling Blast Furnace (TGRBF). However, large additional power consumption for CO2 removal and oxygen generation, and reduction in BF gas export, makes the economic performance of the technology very sensitive to energy prices. Add-on CO2 capture for conventional BF may achieve similar costs (40–50 € /t CO2 avoided), but the CO2 avoidance rate will be only about 15% of the specific CO2 emissions. For the long term future, although there are large uncertainties, advanced CO2 capture technologies do not seem to have significant economic advantages over conventional technologies. The results also indicate that in a carbon-constrained society, when considering new plants, smelting reduction technologies such as the COREX process, may become a strong competitor to conventional blast furnace based steel making process when equipped with CO2 capture. Although conventional iron and steel making using BF is expected to dominate the market in the long term, strong need for drastic CO2 emissions reduction may drive the sector towards large scale implementation of advanced smelting reduction technologies. [Copyright &y& Elsevier]

Abstract: China’s economy has been on a solid fast growth track since 1978. The economy expanded by an average annual rate of about 10% during the last thirty years. That is more than triple the average growth rate of the world economy during the same period. The rapid economic development has been associated with growing energy consumption and carbon dioxide (CO2) emission. Although the first phase of the Kyoto Protocol exempts China from reducing its own CO2 output, China, as the first or second largest CO2 emission country, is facing growing international political pressure. As a responsible big country, China will almost certainly have to respond to climate change in the future. China is entering unexpected fast development period of the industrialization, urbanization and motorization, in which large-scale new infrastructures will be built. This provides great opportunity to plan for longer-term CO2 mitigation—the infrastructures built today have a long life time and are not easy to upgrade the technologies involved, and decisions made now will have a major impact on energy utilization mode and CO2 mitigation technology option in coming years. Carbon Capture and Storage (CCS), as an option in the portfolio of mitigation actions to combat climate change, is expected to have far-reaching implications for China. This paper (1) explores the strategic significance of CCS for China by making an extreme scenario analysis of Chinese power sector in 2030; (2) provides an overview of the recent CCS activities in China; and (3) identifies the major challenges with respect to CCS development in China and put forwards immediate strategies. [Copyright &y& Elsevier]

Abstract: This paper describes a detailed process optimization of the mass and energy balances for multi-stage membrane systems used in coal-fired power plants. Based on the recovery rate of 50% or 90% CO2 with 95 mol% CO2 purity, different concepts using recirculation of flue gas and variation of feed gas compressor and vacuum pump on the permeate side were developed and optimized to obtain minimum energy consumption. Simultaneously, a cost model was developed to make a further analysis of the optimized concept in view of the tradeoff balance between material and energy consumption. [Copyright &y& Elsevier]