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Paper presents parametric evaluation of a modified design of a conceptual micro-combined heat and power unit (micro-CHP) with solid oxide fuel cells. The system incorporates oxygen transport membranes to supply high purity oxygen for post-combustion of lean fuel leaving the SOFC stack. The concentrations of CO 2 in the flue gases leaving the system, approaches 99% (on dry gas basis). High temperature oxygen transport membranes, made of perovskite materials, enable oxygen permeation rate exceeding 6 Nml/(cm 2 min). The oxygen permeation is strongly related to the ratio of oxygen partial pressures at the retentate and permeate sides. Results of a parametric evaluation of the system, including the analysis of effects of membrane characteristics on the electrical efficiency, are presented and discussed. Oxygen transport membranes require high pressure at the feed site, therefore an increase of auxiliary power consumption should be expected to achieve high oxygen flow through the membrane. Electrical penalty in range 6–12%-point was observed, in comparison with a conventional micro-CHP system without oxy-combustion. These numbers are often quoted for large power systems operating in a CCS-ready mode with state-of-the-art oxygen separation methods such as pressure swing adsorption (PSA). Electrical efficiency of the system discussed in this paper was evaluated and effects of oxygen permeation rate on the electrical efficiency were analyzed. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the role of CCS technologies as part of a portfolio for reducing CO2 emissions from the European electricity supply system until the year 2050. The analysis is carried out with the aid of a techno-economic model (with the objective to minimize the total system cost) including a detailed description of the present stationary European electricity supply system (power plants) and potential CO2 storage sites as obtained from the Chalmers Energy Infrastructure databases. The ability of different EU Member States and regions to facilitate and to benefit from CCS will most likely depend on local conditions in terms of current energy mix, fuel supply chains and distance to suitable storage locations. Special emphasis is therefore put on analyzing turn-over in capital stock of the existing power plant infrastructure, timing of investments and the infrastructural implications of large scale introduction of CCS on a regional perspective. The paper discusses the role of and the requirements on CCS for meeting strict CO2 emission reduction targets of 85% reduction from power generation by 2050 relative 1990 emissions in three different scenarios. All analysed scenarios apply the same cap on CO2 emissions. The first scenario includes a continued growth in electricity demand (as presented in EU base-line projections). The second scenario includes stated EU targets for 2020 and indicative targets for 2050 with respect to increased energy efficiency, and thus, considers a lower growth in electricity demand compared to the base-line. The third scenario includes EU targets (to 2020 and indicative targets to 2050) on energy efficiency, equal to the second scenario, and EU targets of electricity from renewables. The results show that it is possible for the European electricity generation system to meet an 85% CO2 reduction target by 2050 with a potentially large contribution from CCS. Up to 50% of the electricity generation will come from plants with CCS with a peak capture estimated to 1.8GtCO2 per year and cumulative CO2 capture of about 39GtCO2 between 2020 and 2050 (it is assumed that CCS will be commercially available from 2020). As expected, countries which currently have high carbon intensity and which are located nearby suitable storage sites will benefit the most from CCS implementation. Hence, the results suggest that Italy has the largest demand for CCS with annual peak capture at around 0.5GtCO2 in the base-line scenario. The model results indicate a steep ramp-up of CCS post-2020, which imposes challenges for timely investments in corresponding CCS infrastructure including transportation and storage. A continued growth in electricity demand can lead to demand for CCS to such extent (in the base-line capacity build up is about 300GW of CCS between 2020 and 2050) that the actual penetration level could be limited by fuel markets and power industries’ ability to supply fuel and CCS power plants. [Copyright &y& Elsevier]

The LNG market connects numerous export and import markets, and the global LNG trade has been growing steadily. Despite the availability of multiple alternatives, only a small fraction of this global cryogenic potential is currently utilized, and a negligible number of regasification terminals are equipped with cold energy recovery systems. This paper explores various options for recovering cold energy from LNG regasification processes including electricity production, refrigeration, cryogenic separation processes, CO 2 capture and liquefaction. The present study examines the industrial recovery options, proposing both conventional and innovative process schemes and analysing them in terms of their thermodynamic modelling and feasibility. Nine case studies were selected and simulated using Aspen Hysys software, considering material and energy balances. Specific energy consumptions are calculated, and an exergetic comparison methodology is adopted to provide a unified approach capable to embrace heterogeneous systems utilizing mechanical/electrical energy, thermal energy, and "chemical energy". The temperature profiles are examined, and sensitivity analyses are performed on key parameters. The integration of direct cooling and condensation brings high exergy efficiency of above 40% and economic advantages due to the absence of an external refrigeration cycle. Coupling regasification with CO 2 liquefaction reduces specific energy consumption by 53% compared to the conventional process. Similarly, in the case of an ethylene production plant, energy consumption is reduced by 95%. Simulations for electricity generation using an ORC cycle with LNG as the cold source achieve around 25% exergy efficiency, but the LCOE (Levelized Cost of Electricity) is attractive, ranging from 0.07 to 0.09 €/kWh. Integration with an Air Separation Unit (ASU) for cryogenic distillation leads to a 41% decrease in specific energy consumption. Further integration with Allam and cascade ORC cycles has been simulated. Globally, air separation shows exergy efficiencies of 37–38%, which is higher than the average 25% obtained from conventional thermodynamic cycles with low-temperature hot sources. Regarding cryogenic CO 2 capture, it exhibits lower specific energy consumption compared to traditional processes. The exergy efficiency is high at 22%, and the LCOP (Levelized Cost of CO2 Production) of 55 €/ton is attractive for carbon capture processes that can be coupled with regasification units and NG utilization (a.e. for hydrogen and electricity production). [ABSTRACT FROM AUTHOR]

The carbon capture by adsorption (CCA) is regarded as an available engineering technology because of its low energy-consumption, easy to control, and possible integration with renewable energy. The recent advances in CCA research comprises mainly about the performance improvement of adsorbents, design and optimization of engineering process. However, considering the time-consuming and intensive funding required for experimental investigation, the numerical simulation has been widely applied in CCA. In numerical simulation field of CCA, the adsorption process is commonly simplified into mathematical models group comprised of adsorption kinetics model, the adsorption equilibrium model, pressure drop model and heat transfer model. However, few studies’ focus is to provide a detailed review of the research methodology of mathematical modeling in CCA simulation. This paper presents a pathway map on CCA mathematical modeling through literature review and case study. An overview of model screening and modeling method of CCA is provided in the review part. This part also provides a short guided tour on how to combine the fundamental models about heat and mass transfer together to form a model group for various application scenarios in CCA. Then the pathway map on CCA modeling, which is summarized based on the review, is applied to a case study. In this part, the adsorption of CO 2 /N 2 mixtures on activated carbon under the conditions of high temperature and low pressure is numerically investigated based on the established models. The performance indicators comprise gas temperature, mole fraction, and adsorbate amount of the fixed bed, are applied in the evaluation performance of CCA. Based on the proposed methodology, the CCA modeling demonstrates a more fluent design process relative to the real physical scenario, with a possible access to further optimization. Particularly, the simulation results showed that the optimized dimensionless velocity for the highest utilization efficiency of the fixed bed can be obtained and thus is proposed as 1.2–1.4 for the most suitable feed velocity to fit different size of fixed bed and different types of adsorbents for the engineering design. [ABSTRACT FROM AUTHOR]

This paper proposes a novel CO 2 capture technology from the integration of partial oxy-combustion and the Calcium-Looping capture process based on the multicycle carbonation/calcination of limestone derived CaO. The concentration of CO 2 in the carbonator reactor is increased by means of partial oxy-combustion, which enhances the multicycle CaO conversion according to thermogravimetric analysis results carried out in our work, thus improving the CO 2 capture efficiency. On the other hand, energy consumption for partial oxy-combustion is substantially reduced as compared to total oxy-combustion. All in all, process simulations indicate that the integration of both processes has potential advantages mainly regarding power plant flexibility whereas the overall energy penalty is not increased. Thus, the resulting energy consumption per kilogram of CO 2 avoided is kept smaller than 4 MJ/kg CO 2 , which remains below the typical values reported for total oxy-combustion and amine based CO 2 capture systems whereas CO 2 capture efficiency is enhanced in comparison with the Calcium-Looping process. [ABSTRACT FROM AUTHOR]

Extracted water—water brought to the surface of the ground during carbon capture and sequestration (CCS) projects to create additional room for carbon dioxide injection—exists in a murky legal environment. As part of a broader attempt to identify the complex interactions between water resource policies and CCS, an analysis was undertaken at both the state and the federal level to scope the policy environments surrounding extracted water policies and laws. Six states (California, Illinois, Mississippi, Montana, North Dakota, and Texas) were chosen for this analysis because either active CCS work is currently underway, or the potential exists for future work. Although regulation of extracted waters could potentially occur at many points along the CCS life cycle, this paper focuses on regulation that may apply when the water is withdrawn—that is, accessed and removed from the saline aquifer—and when it is re-injected in a close but unconnected aquifer. It was found that no regulations exist for this source specifically. In addition, greater input is needed from regulators and policy makers in terms of defining this resource. In particular, regulation of extracted waters (and CCS activities broadly) often overlaps with the management of fluids produced during oil and gas development. Many regulations would apply to extracted waters if they were classified as such. Therefore, correct categorization is key as the industry in this space continues to grow. [ABSTRACT FROM AUTHOR]

Carbon Capture and Storage (CCS) has been viewed as an emission abatement option with great potential in China as coal has dominated China's energy consumption. China has already started to pay attention to CCS, as well as to the proposed the concept of ‘CCUS’ (which adds CO 2 Utilization into the chain of capture, transportation and storage). However, CCS is still in the early stages of its technological development, and the high cost, with several internal and external uncertainties make the role that CCS can play in China's future emission reduction unclear. From the perspective of general equilibrium analysis, this paper introduces CCS into a regional energy–economy–environment integrated assessment model, and makes a comprehensive evaluation of CCS's potential for future development and contribution to emission abatement in China. At climate policy level, the potential contribution of CCS in emission abatement has been evaluated against different future emission constraint scenarios in China. At technological level, the effects of endogenous learning and policy incentives on CCS have been investigated, and the substitution capacities of CCS and Non-hydro renewables to fossil energy have been discussed, as well as their technology penetration rates. Furthermore, the impact of CO 2 utilization on the development of CCS has also been discussed. [ABSTRACT FROM AUTHOR]

This paper evaluates three acid gas removal concepts studied in the project "A Green Sea". Two solvent concepts (aMDEA/MDEA and Selexol) and a low-temperature concept are modelled and assessed, taking different raw natural gases and natural gas product requirements into consideration. The analyses and comparisons of the concepts and cases consider nine criteria in order to include both energy efficiencies and compactness. The assessment shows that acid gas removal using aMDEA/MDEA technology seems to perform well in terms of energy efficiency, volume and weight for low CO2 removal. However, for high CO2 content or strong polishing requirements, the chemical solvent technology loses its efficiency in terms of weight and volume. The assessment shows that the Selexol concept is an inefficient option in terms of energy efficiency, volume and weight, especially when large quantities of CO2 have to be removed from the gas stream. The assessment also shows that the low-temperature technology can be a compact and energy-efficient option, both in the case of strong polishing requirements and high bulk removal of CO2. However, the higher the amount of CO2 to be removed, the less energy efficient is the low-temperature technology. The case evaluation underlines the fact that the aMDEA/MDEA solvent concept exhibits the best or close to the best key performance indicators (KPIs) for all parameters for the RNG1Pipe case (raw natural gas specification 1 to pipeline quality specification) and therefore appears to be the best technology option. For this case, the two other technologies are slightly less energy efficient than the aMDEA/MDEA, but both are significantly less compact. For the RNG1 LNG (raw natural gas specification 1 to LNG quality specification) case, the aMDEA/MDEA and low-temperature concepts have similar KPIs. The chemical solvent technology, however, is slightly more energy efficient and compact and would therefore be preferred for the RNG1 LNG case. Finally, the RNG2 Pipe (raw natural gas specification 2 to pipeline quality specification) case shows that the low-temperature technology can be a compact option for acid gas removal, which is a critical factor in the case of offshore applications for both the equipment costs and the weight constraints on the platform. Despite its lower energy efficiency, it is therefore likely that the low-temperature technology will be selected in the RNG2 Pipe case. This choice is strengthened by some regulations which recommend that solvents such as MDEA and aMDEA should be phased out for offshore applications, as is seen, e.g. in Norway. In addition, if stricter regulations are also enforced for onshore applications, this might also argue in favour of the low-temperature technology or other chemical solvents that are otherwise less efficient than aMDEA/MDEA.Finally, the potential of hybrid concepts is discussed and suggested for future works, in order to combine the advantages of the different technologies, such as the energy-efficient performances of the aMDEA/MDEA concept and the compactness of the low-temperature concept. Three acid gas removal concepts are studied and compared using multi-criteria analyses. Three cases taking different raw natural gases and natural gas product requirements are considered. The assessment illustrates each technology trends, as well as comparison over cases. The aMDEA/MDEA technology seems to perform well for low CO2 removal. The low-temperature technology can be an efficient option for high bulk removal and polishing. [ABSTRACT FROM AUTHOR]

Abstract: Full chain energy performance is applied to a hybrid combined cooling, heating and power (CCHP) system running with methanol and solar energy. Results show that the overall energy efficiencies of six different cases range from 40% to 50% in summer condition, and 38% to 47% in winter condition. Combined with the traditional methanol production process, the CCHP systems are not energy efficient compared to the traditional energy supply systems from a full chain viewpoint no matter whether the solar energy is utilized. While combined with a polygeneration (PG) or polygeneration with CO2 capture (PG+CC) process, the CCHP system could achieve obvious improvements in overall energy efficiency due to the benefits from cogeneration and solar energy utilization, and thus could yield a high fossil energy saving ratio in comparison with the traditional energy supply system. The findings presented in this paper indicate that the complementation utilization of solar energy and fossil fuels through thermochemistry reactions is energy efficient and could be one of the potential options to utilize solar energy. [Copyright &y& Elsevier]

Abstract: So far CO2 shipping has only been introduced as a secondary option for long distances and small amounts because of the prevailing idea that CO2 shipping is more expensive than CO2 pipeline for transporting large amount CO2. This paper shows that CO2 terminal and large CO2 carrier can play a role of collecting CO2 from several sources and transporting CO2 in large volume so transport cost per tonnage of CO2 can be reduce in commercialized CCS market. Multi-stage CO2 liquefaction processes are developed to reduce total cost of CO2 compression and transport. For high pressure CO2 inlet stream, newly developed multi-stage liquefaction process with serial flash tanks enables power consumption reduced to 44% compared to single stage liquefaction process. By adopting new design concept of very large CO2 Carrier more than 40,000m3, optimal size of CO2 carrier can be provided for each voyage route and total cost of CO2 compression and transport is reduced. The results of economic assessment of CO2 transport show that CO2 shipping is economically competitive to CO2 pipeline even in the distance of 200–300km for large amount of CO2 transport such as 10Mt CO2/year or 20Mt CO2/year. CO2 transport by ship should be seriously re-considered as an effective transport method for commercialized CCS projects as well as early demonstration projects. [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: 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: For most CCS projects, captured CO2 is transported by pipeline, in contrast to shipping it, which has only been introduced as a secondary option for long distances and small amounts. This paper provides some possible alternatives to reduce the total cost of CCS through CO2 shipping. The benefits of HP pump in power consumption is considered and a new total CCS chain is suggested, which can be divided into capture, liquefaction (or compression to supercritical fluid), transport by ship, compression by HP pump, and storage. With a highly efficient liquefaction process, CO2 shipping costs can be reduced under a new total CCS chain. The results of our study show that an optimal size needs to be adopted for each CCS project, enabling CO2 shipping to be more cost efficient. DSME has developed a concept design for a large CO2 carrier that has the potential to be more cost-effective than conventional transport. Therefore, CO2 transport by ship should now be seriously re-considered as an effective transport method on a project-by-project basis. [Copyright &y& Elsevier]

Abstract: This paper presents an environmental assessment of three scenarios postulating a national deployment of the Carbon Capture and Storage (CCS) chain by 2020–2050 on the French biggest industrial CO2 emitters (41 emitters among 9 industrial sectors) that had been carried out as part of the SOCECO2 project. 1 [1] SOCECO2 project, funded by the French National Research Agency, 2006–2009, involving the following partners: ALSTOM Power, APESA, BRGM, CNRS-CIRED, GDF Suez, IFP Energies nouvelles, INERIS, TOTAL. This analysis is based on the comparison of these CCS scenarios with reference scenarios without CCS at the same timeframe. Results detailed below focus on greenhouse gas (GHG) emissions and energy consumption, although NOx and SOx emissions balances have also been evaluated in the same project. Conclusions of this study provide information about the extent and main contributing factors of potential environmental outcomes (negative or positive) associated to CCS deployment. [Copyright &y& Elsevier]

Abstract: Using CO2/N2 gas separation membranes for post-combustion capture, the most important problem is how to create the driving force efficiently because the feed flue gas has only ambient pressure and a relatively low CO2 content. In order to fulfill the separation target – 95mol% CO2 purity and appropriate degree of CO2 separation – multi-stage systems are necessary using feasible membranes. This paper describes a detailed parametric study for multi-stage membrane systems used in a coal-fired power plant. According to the above-mentioned boundary conditions, the investigation process was divided into two steps: (a) energy consumption and (b) capture cost analyses. In the first step, by varying the position of the compressors and vacuum pumps and recycling the flue gas to the feed side, cascade variants were developed and analyzed in detail. The cascade system was integrated in the 600MW North Rhine-Westphalia reference power plant and compared with the chemical absorption process. In the second step, an economic model was developed to make a further analysis of the cascade system. A correlation was established between the membrane parameters (selectivity, permeability) and system performance (energy consumption, capture cost). [Copyright &y& Elsevier]

Abstract: The European DYNAMIS project is part of the HYPOGEN quick-start programme and aims at investigating viable routes for large-scale cost-effective combined hydrogen and electricity production with integrated CO2 Capture and geological Storage. This paper presents the environmental evaluation carried out for each technology option studied, producing Hydrogen and Electricity with CCS. The methodology used is based on Life Cycle Analysis (LCA) principles and concentrates on the assessment of two criteria: GHG emissions and non renewable primary energy consumption. As with other evaluations performed in DYNAMIS (mainly focused on technical and economic aspects), these results lead to the selection of best concepts in terms of environmental efficiency by comparing and weighing up positive and negative effects (i.e GHG emissions reduction and increase of non-renewable primary energy consumption). [Copyright &y& Elsevier]

• Small-scale carbon capture applications can be very efficient. • Oxyfuel combustion in lime kilns require less fuel but more electricity. • Electric arc plasma calcination switches entirely from use of fuel to electricity. • The additional energy demand to capture CO 2 is small. • 4-bar steam could be produced in conjunction with carbon capture. Carbon capture from the calcination process in Kraft pulp mills, also known as sulphate pulp mills, has potential as a part of carbon capture and storage (CCS) infrastructure deployment. Growing concern of climate change is increasing the interest for so-called negative emission technologies (NETs), and large emission points have great potential. However, among other factors, lack of financial incentives, trade-off with investments in existing products, and the necessity of large infrastructure that stretch across country borders, constrain deployment. This study investigates two concepts for carbon capture in combination with lime kilns in Kraft pulp mills: oxyfuel combustion and electric arc plasma calcination. The results from the modelling of six configurations show that carbon capture from the calcination process with these technologies can be made with comparatively low additional energy demand. Sulphate pulp production from Kraft pulp mills, which use lime kilns, is increasing in Europe and in the world. Therefore, there is large potential for capture of CO 2 from these alternative calcination technologies, both as a first step towards and as a part of a large-scale deployment of CCS and bioenergy with CCS (BECCS). [ABSTRACT FROM AUTHOR]