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In this paper an approach for analysing the potential for implementation of different technology pathways for the European pulp and paper industry (PPI) is presented. The approach is based on detailed technical research and aggregates the knowledge from previous studies to incorporate the whole European PPI. Thus, the potential for different technology pathways can be estimated on a European level whilst still considering important characteristics of individual mills. The usefulness of the approach was exemplified by applying it to a case study of the potential for introduction of carbon capture and storage (CCS) within the European PPI. The results from the case study show that for the European PPI, CCS has an up-hill road in order to be a viable, large scale alternative for reduction of CO2 emissions. If CCS is to be introduced in large scale within the European PPI, large biomass-based point sources of CO2 emissions need to be included when planning for CCS infrastructure and also the infrastructure needs to be built out for clusters emitting <20 MtCO2/yr. [ABSTRACT FROM AUTHOR]

Abstract Carbon capture and storage (CCS) is now known to be an effective way to reduce greenhouse gas emissions especially CO 2 to the atmosphere. Amino acid salt (AAS) solutions are regarded as promising CO 2 absorbents compared to traditional amine solutions, as they are environmentally being with lower evaporation as well as fewer degradation issues. This paper is intended to review recent developments in CO 2 capture using AASs. The thermodynamics and kinetics of CO 2 and different AASs are illustrated in detail. We will also discuss the blended solutions containing AASs in terms of applications and absorption or regeneration performance. Additionally, we will present specific directions for future research on CO 2 -AAS systems. This paper could provide a guideline for effective carbon capture by new absorbents. Highlights • A comprehensive review of amino acid salts fundamentals is introduced. • Detailed thermodynamics and kinetics between CO 2 and various amino acid salts are discussed. • The developments of CO 2 capture by amino acid salts in the fields of biogas upgrading, natural gas and flue gas purification are illustrated. [ABSTRACT FROM AUTHOR]

This study summarizes the OASIS (Overburden Analysis and Seal Integrity Study for CO 2 Sequestration in the North Sea) project that focuses on assessing the containment risks associated with the geological carbon sequestration (CCS) of the Northern Lights project. CCS is viewed as one of the most effective solutions for reducing carbon emissions, as it captures carbon dioxide from point sources and permanently stores it in suitable geological formations. However, injecting CO 2 into the subsurface may have mechanical consequences, including fault reactivation, top seal fracturing, surface heave, etc. This study proposes an interdisciplinary workflow to characterize the caprock, faults, and overburden associated with CCS projects in the Horda Platform area, to improve injection-induced containment risk assessment. Our findings show that the proposed workflows and tools effectively characterize stress-related mechanical hazards. However, due to the complex nature of rocks, it is challenging to evaluate the top seal integrity using a single method. Therefore, the proposed interdisciplinary approach is more effective for any fluid injection site's characterization, given the complex nature of the subsurface and its behavior under injection-induced stress changes. This research paper adds knowledge about the top seal integrity assessment and the reliability of injected CO 2 , making CCS projects more reliable and safer. Although this study focuses on the northern North Sea, the proposed methods are equally applicable globally to characterize subsurface CO 2 storage sites. Apart from CCS projects, these research results can benefit other subsurface injection projects, such as water injection for reservoir management, wastewater injection for disposal, hydrogen storage, and hydraulic fracturing for unconventional hydrocarbon resources. • Brittleness indices property can reflect the rock integrity. • Seismic inverted properties resolve the data limitation issues within the overburden intervals. • An analytical structural reliability model can help evaluate the top sealing risks quickly. • Overburden interval rock properties must be realistic in any 3D field-scale geological models. • An interdisciplinary workflow is required for subsurface CCS site characterization. [ABSTRACT FROM AUTHOR]

This paper presents the results of chemical looping combustion (CLC) research. Nowadays, CLC is one of the best prospective combustion technologies, because it enables the production of a concentrated carbon dioxide (CO 2 ) stream, following water condensation, without any energy penalty for its separation. The objective of this work was to study chemical looping reaction performance with the application of novel perovskite-type oxygen carriers (OCs). Sr(Fe 1-x Cu x )O 3-δ family members were tested for hydrogen combustion for power generation purposes. Sr(Fe 1-x Cu x )O 3-δ , which is a perovskite-type oxide, was prepared using the calcination method, where x = 0, 0.1 and 0.33. Reactivity tests were performed using a thermogravimetric analyser (TGA, Netzsch STA 409 PG Luxx) under isothermal conditions in multiple reduction–oxidation cycles. Both the temperature (600–800 °C) and number of redox cycles (five cycles) effects on the reaction performance of recently developed OC samples were evaluated in the study. TGA data were used for the assessment of the oxygen transport capacity value, redox reaction rates and stability. Sr(Fe 1-x Cu x )O 3-δ showed an excellent stable chemical looping performance. The changing of oxygen content (3.8–4.86 wt%) occurred within approximately 2 min, with the chemical properties of the material maintained during the cycling combustion tests. In addition, new SrFeO 3-δ OCs, doped with copper (Cu) perovskite-type materials, were analysed using multiple methods: X-ray powder diffraction (XRD); scanning electron microscopy (SEM); surface area by Brunauer–Emmett–Teller (BET) method; and melting behaviour study. In terms of physical properties, the new OCs can resist both high CLC process temperatures and mechanical forces, which are essentially useful. The analysis showed that Sr(Fe 1-x Cu x )O 3-δ carriers performed at extremely high melting temperatures (>1280 °C). Results of crushing strength testing showed that developed materials had a pronounced mechanical resistivity with a crushing strength higher than 1 N and will perform well in fluidized beds (4.31–6.23 N). In this paper, it was demonstrated that known mixed oxygen-ionic and electronic conducting membrane materials such as Sr(Fe 1-x Cu x )O 3-δ might also be applied as oxygen carriers. Overall results demonstrated Fe-Cu-based perovskites might be successfully used as OCs in the chemical looping combustion process. [ABSTRACT FROM AUTHOR]

• The risk of injectivity loss during CCS operations observed in lab scale is also applicable to field scale. • Several mechanisms can impact the injectivity, due to the potential of reducing permeability, especially in cases with lower permeability reservoirs. • Non-Darcy effect showed no impact on well injectivity for a wide range of injection rates. • Negligible effect of the trapped gas trapped on the CO 2 injectivity. This paper aims to review the main mechanisms identified in the lab scale that impact CO 2 injectivity during CCS projects in saline aquifers and evaluate their relevance in field scale through numerical models. They may include water vaporization, salt precipitation in the dry-out zone, mineral dissolution, which can result in fines migration in porous media, CO 2 hydrate formation, and effects of non-Darcy flow. All those mechanisms are observed from lab experiments and significantly impact reservoir petrophysical properties such as porosity and permeability and consequently on injectivity in field operations. This study includes these mechanisms in numerical models to quantify their impacts on the CO 2 injectivity well index in synthetic and real field cases. In addition, a sensitivity analysis was performed for a range of brine compositions of seawater and higher salinities. This analysis shows an additional injectivity reduction as the salinity increases due to the halite scale, in agreement with the lab data from the literature. Another dependence evaluated in this study is when the ratio between capillary and viscous forces is decreased, reducing the injectivity. Additionally, when mineral reaction dissolution is considered in our modeling, it is possible to observe two occurring competitive phenomena, where the mineral dissolution can compensate for part of the injectivity loss due to salt deposition in the dry-out zone. That is especially relevant when the reservoir rock matrix is rich in reactive minerals, such as calcite and dolomite. However, mineral dissolution may lead to fines, and the risk of fines migration can lower the injectivity by at least 10% within five years of CO 2 injection, according to our results. The mineral dissolution is also considered in these calculations, and the loss in injectivity is the net result of dissolution and fines migration. The gain in porosity–permeability as the results of mineral dissolution was modeled using the Kozeny-Carman equation. The results show the importance of considering the uncertainty of injectivity loss in CCS projects, where the amount of CO 2 captured for storage must be injected often with no other alternatives, highlighting the need to provide flexibility in project planning to deal with such risks. [ABSTRACT FROM AUTHOR]

Traditional technologies of carbon capture and storage (CCS) are being focused on capturing CO 2 in large-scale demonstrations, which has been proved to result in the high cost and energy penalty. Meanwhile, typical innovative measures, commonly defined as the second generation CCS technologies, elude conventional ones by integrating with solar energy and thus contributing to a more energy-efficient conversion of CO 2 . However, few reviews pay attention to thermodynamic processes and parameters of these novel technologies, and there is a lack of systematic evaluation and comparison among them. This paper firstly presents a guided tour on the state-of-art of typical and innovative CCS technologies integrated with solar energy. An overview on thermodynamic processes, including chemical reactions, operating conditions and efficiency indexes of five typical technologies is presented so that the current development level can be clarified. Since the high energy requirement and related operating cost are the main barriers to the application of existing CCS technologies, the minimum work and second-law efficiency are applied as the main indicators in the second part of this paper which relates to performance evaluation. In addition, the performance windows for innovative technologies are illustrated for the comparison of technological maturity. The results show that energy requirement of innovative CCS technologies from the flue gas is avg. 100–200 kJ/mol CO 2 and the second-law efficiency of them is only 5–12%. Therefore, the maturity and popularity of these novel technologies are still relatively low. But the well-integrated systems and diversified output of these technologies can benefit existing energy infrastructures in a long period. [ABSTRACT FROM AUTHOR]

CO 2 carriers are considered as a solution for CO 2 transport as a part of Carbon Capture and Storage. CO 2 carriers' design is similar to that of commercial liquefied gas carriers and core technology of liquefied gas carriers is to handle boil-off gas during voyages. This paper introduced newly developed CO 2 boil-off gas re-liquefaction processes making use of cold LNG fuel and investigated economic feasibility of newly developed processes by comparison with a conventional boil-off gas re-liquefaction process. New processes enabled considerable main equipment costs saving and additional fuel cost saving for re-liquefying boil-off gas. Simulation study results showed total amount of boil-off gas in a LNG fueled CO 2 carrier could be re-liquefied by LNG fuel consumed during the voyage and comparative cost assessment results demonstrated those newly developed processes could be applied into a LNG fueled CO 2 carrier with insignificant additional cost. The finding of this paper confirms those newly introduced processes are technically and commercially feasible at present and will contribute to growing the potential market of LNG as a marine fuel as well as commercializing CCS technology by providing more cost-effective solution for CO 2 shipping. [ABSTRACT FROM AUTHOR]

This paper investigates various alternatives for the application of CCS at a cement plant which is one of the focus site for CCS deployment in Norway. A matrix consisting of nine CCS alternative chains is analysed in order to quantify cost reduction potentials across the CCS value chain based on an in-house techno-economic assessment methodology and tool called iCCS. In particular, the paper quantifies the strong cost reduction potential of second generation capture technologies and transport technology selection. CO 2 EOR is also identified to have a strong potential to reduce the overall CCS cost, however the cost benefits are strongly dependent on the oil value and the considered EOR injection period. The impact of the inclusion of CO 2 capture and conditioning in the cost of cement shows that public financial support will be required to ensure that the plant remain competitive under current cement market price. Finally, comparison of the full-scale capture versus part-scale capture shows, in this case, that the economies of scale are nearly compensated by the additional steam cost, therefore limiting the interest for full-scale implementation. However, joint deployment with the two other CCS potential sites in Norway (Yara and Klemenstrud) may bring more synergies. [ABSTRACT FROM AUTHOR]

Engineering efforts to handle contemporary energy supply challenges and mitigate pollutant emission lead towards more complicated systems. Power plants are supplementing with additional processing units, alternative production modes and higher level of automation. Wind and solar sources, biomass combustion, gasification, carbon capture and storage (CCS), and cogeneration have appeared as important players in the energy systems. The increasing complexity comprises a risk that the systems become less manageable and less stable than currently. Traditional steady-state engineering methods cannot fully address these challenges that are inherently dynamic in their nature. Dynamic process simulation appears as important tool to the systems design and optimisation tasks. A large variety of dynamic process modelling and simulation approaches has been presented recent years. This paper presents a brief review of methods and simulation packages that are generally applied for studying energy systems' transient behaviour. A CCS capable power plant is presented as an example of utilizing dynamic process simulation for virtual evaluation of a novel electricity production concept. The modelling was performed using two simulators Apros and Aspen Plus Dynamics, which were linked together for dynamic simulating the full chain of cryogenic oxygen distillation, oxy combustion, turbine islands and carbon dioxide purification and liquefaction operations. • Dynamic simulations for design and optimisation of contemporary energy systems have been reviewed. • A case study for evaluating oxy combustion CFB boiler cycle with carbon capturing is presented. • Co-simulation with two dynamic process simulation software: Apros and Aspen Plus Dynamics were shown. • Flexibility aspects of oxy combustion power plant are discussed. [ABSTRACT FROM AUTHOR]

Abstract Integrating solar-thermal energy into the power plant with post-combustion carbon capture and storage can reduce the energy penalty derived from solvent regeneration. However, few metrics exist to evaluate the trade-off associated with technic, economic and ecological perspectives for different integration schemes of the three subsystems, namely the solar field, power plant and carbon capture system. This paper analysis five configurations of coal-fired power plant with and without solar field as well as CCS technology based on the resilience concept. Still at the budding stage, the status of resilience definitions and evaluation methods related to energy system is reviewed. The resilience level for five configurations of coal-fired power plant both with and without solar-field, together with the CCS system is measured, which takes into consideration five critical characteristics towards resilience: fossil fuel depletion potential (CADP), global warming potential (GWP), levelized cost of energy (LCOE), solar to electricity fraction and spare capacity. Results indicate that among all the configurations, the solar-assisted power generation CCS power plant with 90% capture rate shows the highest resilience level. However, the scheme which utilizes solar energy to assisted solvent regeneration, shows limited advantage in terms of resilience level due to high CADP and LCOE. Highlights • Resilience concept and evaluation studies concerning energy systems are reviewed. • A resilience index measure is proposed for solar-assisted CCS energy systems. • Five resilience indicators are covered. • The solar hybrid CCS power plant shows the highest resilience level [ABSTRACT FROM AUTHOR]

Abstract Gas chimneys are geological features that are associated with seal bypass systems. Knowledge of the capacity of the seal is important for the evaluation of the petroleum systems and Carbon Capture and Storage (CCS) studies. The seal is breached when the capillary pressure threshold is exceeded by the underlying buoyancy pressure. The chaotic seismic character that is generally associated with the gas chimneys has been studied previously to evaluate the origin and geometry of the chimneys. Seismic attributes have also been used to determine the character of the gas chimneys and the potential association of hydrocarbon fields. However, it is important to evaluate the sealing potential of the cap rock in the vicinity of the gas chimney. This paper demonstrates that the chimney can be used as a calibration point and, with the use of seismic attributes, variations of sealing capacity can be evaluated. Out of many existing seismic attributes, understanding the shale structure is crucial to narrow the search criteria for the right class of attributes. Using the most useful stream of seismic attributes, the average sealing potential of the Lakes Entrance Formation is estimated. The sealing capacity map across the field is then shown to help evaluate the prospectivity of the area of study and may upgrade subsequent play fairway maps. Highlights • Sealing potential of the Lakes Entrance Formation was investigated. • Applications of seismic attributes to predict sealing potential were tested. • Seismic Anisotropy and attributes show consistent results in predicting the sealing capacity. • The gas chimney was used as a calibration point for the seal failure. • All relevant attributes were used to set a prediction process for sealing potential. [ABSTRACT FROM AUTHOR]

Abstract: Black liquor gasification (BLG) is being developed as an alternative technology for energy and chemical recovery in kraft pulp mills. This study compares BLG – with downstream production of DME (dimethyl ether) or electricity – with recovery boiler-based pulping biorefinery concepts for different types of mills. The comparison is based on profitability as well as CO2 emissions, using different future energy market scenarios. The possibility for carbon capture and storage (CCS) is considered. The results show that, if commercialised, BLG with DME production could be profitable for both market pulp mills and integrated pulp and paper mills in all energy market scenarios considered. Recovery boiler-based biorefinery concepts including extraction of lignin or solid biomass gasification with DME production could also be profitable for market and integrated mills, respectively. If the mill is located close to an infrastructure for CO2 collection and transportation, CCS significantly improves profitability in scenarios with a high CO2 emissions charge, for both combustion- and gasification-based systems. Concepts that include CCS generally show a large potential for reduction of global CO2 emissions. Few of the concepts without CCS achieve a significant reduction of CO2 emissions, especially for integrated mills. [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]

This paper explores the adsorption behaviour of geomaterials in the framework of CO 2 sequestration in shallow level coal seams. Manometric adsorption experiments were carried out on two anthracite coal samples, two rock samples from East Irish Sea, MX80-bentonite, Speswhite kaolinite, dry, wet and biofilm-laden (Bascillus mojavensis -laden) sand at subcritical pressure range (up to 6.4 MPa) of isothermal condition at 298.15 K. The experiments were aimed to investigate the influence of the biogeological conditions of coal and caprock constitutions on CO 2 adsorption. At lower pressures, the moisture had an influence on the CO 2 adsorption on coal resulted in reduced adsorption capacity. At elevated pressures, the volume expulsion behaviour and coal-water interaction had an influence on the adsorption capacities of moist coal sample and resulted in comparable adsorption capacities to dry sample. The disparity in the adsorption capacities between the wet powdered and wet intact core samples showed that the results obtained with powder samples may not reflect the field conditions. Wet conditions and Bascillus mojavensis bacteria influenced the adsorption capacity of sand and showed CO 2 chemisorption capacity. The desorption isotherm pattern of wet and biofilm sand showed that the CO 2 was continuously adsorbed independent of the gas phase pressure. Among the clay minerals, bentonite had greater affinity towards CO 2. Despite the fact that the adsorption capacity of the cap rock is smaller than that of the coal samples, the experimental investigation with constituents of the cap rock provides insights into the effect of biogeological conditions of coal and rock sample constituents on CO 2 storage in coal seams. [ABSTRACT FROM AUTHOR]

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]

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 discusses the economic impacts of climate change, including those on ecosystems, and whether a new backstop technology should be used under conditions of strict temperature targets. Using the dynamic integrated climate-economy (DICE) model, we developed a new model to calculate the optimal path by considering new backstop technologies, such as CO 2 capture and storage (CCS). We identify the effects of parameter changes based on the resulting differences in CO 2 leakage and sites, and we analyse the feasibility of CCS. In addition, we focus on ocean acidification and consider the impact on economic activity. As a result, when CCS is assumed to carry a risk of CO 2 leakage and acidification is considered to result in a decrease in utility, we find that CCS can only delay the effects of climate change, but its use is necessary to achieve strict targets, such as a 1.5 °C limit. This observation suggests that if the target temperature is too tight, we might end up employing a technology that sacrifices the ecosystem too greatly. [ABSTRACT FROM AUTHOR]

In this paper, a novel carbon capture and utilization process is proposed. It is based on using a fraction of the captured carbon dioxide to produce sodium bicarbonate, a widely used product in the chemical and food industries. The process couples the Dry Carbonate process for carbon dioxide capture with sodium bicarbonate production. Raw material is trona or sodium sesquicarbonate dehydrate, which is a relatively abundant mineral composed by approximately 46% sodium carbonate and 35% sodium bicarbonate by weight. In the process, trona is firstly converted into sodium carbonate in a fluidized bed reactor operated at 180–200 °C and 1 bar. Heat required in the fluidized bed reactor for decomposing trona can be supplied by renewable sources such as low/medium temperature solar energy or biomass. A fraction of the sodium carbonate generated is recirculated for carbon dioxide capture by means of the dry carbonate process. The rest is converted to sodium bicarbonate in a carbonating tower through the reaction with carbon dioxide and water. After separation of sodium bicarbonate and other salts from water, the sodium bicarbonate produced is suitable for direct sale. The use of renewable sources for supplying the energy required at the sorbent regenerator and for trona decomposition yields a near-zero carbon dioxide emissions global system. As case of study, carbon dioxide capture coupled to sodium bicarbonate production has been analysed for a 15 MW el coal fired power plant. Heat required in the carbon capture process penalizes the global system efficiency by a 10.2%, which is reduced just to the electricity parasitic consumption for solids transport and carbon dioxide compression (∼3%) if renewable energy sources are integrated. From an economic perspective, the penalty in electricity consumption is fully compensated by the new by-product sales. Taking into account the reduction of electricity sales and current prices of trona and sodium bicarbonate a return of investment is obtained in the range between 3 and 8.7 years with an internal rate of return over 12%. These values improve the current forecast of any other carbon capture and storage process up to date, which suggests a high interest of the proposed conceptual integration specially for regions where trona is widely available. [ABSTRACT FROM AUTHOR]

• A novel decarbonization concept applied to offshore natural gas wells benefiting CCUS technology. • A comprehensive CFD model considers real gas EOS and the behaviours of gas, droplets, liquid film. • Compatible with pure CO 2 and CH 4 -CO 2 models to study condensation and separation characteristics. • The maximum CO 2 condensation amount under high pressure and low temperature is 10.33 ton/h. • The maximum CO 2 capture capacity is 4.43 ton/h with high heterogeneous droplet mass concentration. Carbon capture, utilisation and storage (CCUS) is of unique significance for building a green and resilient energy system, and it is also a key solution to tackle the climate challenge. The concept of supersonic decarburization, a joint product of non-equilibrium condensation and swirling separation, can contribute to CCUS technology in a clean way. In this paper, a numerical model is established and validated to investigate the complex physical phenomena of supersonic decarbonization in a high-pressure environment based on the real gas equation of state. The model is compatible with the pure CO 2 model and CH 4 -CO 2 model. Through the simulation of the supersonic nozzle and supersonic separator, the condensation and separation performance of supersonic decarbonization technology was evaluated. For the condensation performance of carbon dioxide, the results show that higher pressure makes it much easier to achieve the condensation process. When the pressure is supercritical, the decrease of inlet temperature or the increase of inlet mole fraction of CO 2 leads to a higher liquid fraction. For separation performance, when the mass concentration of inlet heterogeneous droplets increases from 0.1 kg/m3 to 7.5 kg/m3, the carbon separation amount increases from 3.33 ton/h to 4.43 ton/h, while the exergy loss of condensed CO 2 drops from 436.57 kJ/kg to 329.56 kJ/kg. It demonstrates that the decarburization process is easier, and exergy required for condensation decreases when the concentration of the foreign core is larger. This new concept is beneficial to CCUS technology and can be applied to carbon capture in offshore natural gas processing. [ABSTRACT FROM AUTHOR]

Partition (or distribution) coefficients determine the relative equilibrium concentrations of chemical constituents (or chemical tracers) in each of the phases of a multi-phase system under dilute conditions. The various fluid phases in a reservoir have differing transport properties (e.g. varying relative permeability) and to correctly interpret the behaviour of injected chemical tracers it is essential that accurate partition coefficients are known. In the context of carbon geosequestration or long-term storage of CO 2 , chemical tracers will be predominantly exposed to an environment consisting of supercritical CO 2 and formation water as the main fluid phases. To estimate/simulate the reservoir properties relevant to injected CO 2 tagged with chemical tracers, it is therefore necessary to incorporate high pressure/temperature CO 2 /water partition coefficients into any model/simulation. In this paper, we present a method to determine these partition coefficients for gaseous chemical tracers using a variation of the widely used EPICS (or equilibrium partitioning in a closed system) method. With this method, only the concentration in one phase (in this case, CO 2 ) needs to be measured. We then report these values for a series of representative chemical tracers (i.e. krypton, xenon, sulfur hexafluoride, perdeuterated methane and R134a) at pressure/temperature conditions that have been previously used at the CO2CRC's Otway CCS demonstration project in Victoria, Australia. These values were generally lower than the corresponding Henry's Law coefficients at comparable temperatures. Experiments also examined the impact of adding CH 4 to the system to mimic feedstock gas at the CO2CRC Otway project and provide data pertinent to scenarios where CO 2 is injected into depleted CH 4 gas fields. These values are compared with Henry's Law coefficients and another recently published set of high pressure/temperature partition coefficients. With computational simulations, we have shown that these differences are potentially significant and demonstrate their impact in three typical CO 2 geo-sequestration scenarios (i.e. injection into two types of aquifers and injection into a depleted reservoir with a gas cap). [ABSTRACT FROM AUTHOR]

This paper discusses the limitations and prospects of using equilibrium-based column models for the dynamic simulation of post-combustion CO 2 capture processes. Based on their features, one of three available commercial process simulators was chosen for this study. A pilot plant configuration adopted from literature was modeled and simulated using this simulator. Simulation results were compared with plant data and with results using standard rate-based models as available in literature. Temperature profiles in columns and overall mass and energy balances were found to be similar to plant data; however, CO 2 capture-rate, reboiler-duty, and rich-loading using the model were overestimated. A method of reduced stage efficiencies in the absorber was used, which improved performance prediction further with a maximum deviation of 5%. Further, this dynamic model was used to analyze the process subjected to variation in flue gas flow-rate with a similar trend of futuristic power plants by controlling either liquid to gas ratio or CO 2 capture-rate. Controlling liquid to gas ratio provided more control over the reboiler-duty while controlling the capture-rate focused on maintaining a certain capture ratio. The advantages and disadvantages of both methods are discussed and based on that, the controlling capture ratio was found suitable for using while power plant works flexibly with stringent emission regulations. [ABSTRACT FROM AUTHOR]

In the present paper, a CO 2 cryogenic capture for flue gas of an LNG-fired power generation system is proposed, in which LNG cold energy can be fully utilized during the gasification process. First of all, the flue gas is compressed to facilitate the CO 2 solid formation and separation. Sequentially, the CO 2 -removed flue gas expands to supply most of the cold energy needed for the cryogenic process. In comparison with traditional CO 2 -capture systems in LNG-fired power generation cycle, the new system does not require gasifying excessive amount of LNG. Based on the HYSYS simulation, the CO 2 capture pressure and temperature are investigated as the key parameters to find the appropriate working conditions of the CO 2 -capture system. The results show that the system can achieve a 90% CO 2 recovery rate or higher if the flue gas temperature can be lowered to less than −140 °C. [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]

Carbon capture and storage (CCS) will be a critical component of a portfolio of low-carbon energy technologies required to combat climate change ( IEA-GHG, 2013 ). As such, an extensive transportation infrastructure will be required to transport captured CO 2 from different sources to the available sinks. Several studies in the literature suggest that shared oversized pipeline networks may be the most efficient long term option compared to single source to sink pipelines, based on increased CCS deployment over the years and therefore increased CO 2 flowrate to the transport network. However, what is neglected in this vision is that the deployment of intermittent renewable energy tends to displace thermal power generation. This directly reduces the amount of fossil fuel burned, CO 2 produced, captured and transported through the network. This paper presents an optimisation methodology to “right-size” CO 2 transport infrastructure, explicitly accounting for the transient flow of CO 2 arising from the co-deployment of intermittent renewable energy generators. By application of this methodology, we demonstrate that capital cost reductions of up to 28% are possible relative to a business-as-usual design case. [ABSTRACT FROM AUTHOR]

CO 2 carriers are considered as a solution for CO 2 transport as a part of carbon capture and storage (CCS) and ship fuel cost is an important parameter impacting total cost of CO 2 shipping. Heavy fuel oil (HFO) is a traditional marine fuel but alternative marine fuels such as MGO and LNG shall be considered for future researches on CO 2 shipping because low sulphur content fuel is required in sulphur Emission Control Areas (SECAs) from January 2015. However, LNG has not been seriously considered as a marine fuel for CO 2 carriers and its economic feasibility has not been studied so far. This paper assesses economics of LNG fueled CO 2 carriers based on a CO 2 shipping scenario in North Sea and fuel price in June 2016. Parameter studies are conducted to understand the influence of important parameters such as a marine fuel price, LNG fuel system cost, and small LNG distribution cost. The results show that LNG fueled CO 2 carriers are more cost-effective than CO 2 carriers utilizing MGO based on fuel price in June 2016 and when crude oil price is higher than approximately 30–50 USD/bbl. Furthermore, technology development on LNG fuel system and bunkering infrastructure could strengthen the competitiveness of LNG as a marine fuel for CO 2 carriers. [ABSTRACT FROM AUTHOR]

The Steady State Superconducting Tokamak (SST-1) consists of many distributed and heterogeneous plant/experiment systems viz. Water-Cooling, Power Supplies, Cryogenics, Vacuum, Magnets, Auxiliary-Heating sources, Diagnostics, Front End Electronics (FEE) & Data Acquisition systems, having their own data acquisition & control systems and control & monitor by Central Control System (CCS) during the machine operation. With distributed computing and interdependent systems, it is essential that all the data/event acquired must be with disciplined & precise time-base, so as to make the co-relation of the data/event from various plant and experiment systems easy. Hence it is important to have accurate and precise Time Synchronization in place. The two systems fulfill the requirement of the time synchronization in SST-1. The VME based Timing System (TS) provides synchronization amongst various experiment systems during the plasma discharges and works as discharge control system (DCS) while the GPS based Time Synchronization System (TSS) caters the requirement of synchronization during the continuous operation of various plant systems by feeding a central clock to all the plant systems. This paper presents the Time Synchronization System of SST-1, the results of the integrated testing and engineering validation with various SST-1 subsystems. [ABSTRACT FROM AUTHOR]

In this paper, the methods of the integration of a supercritical coal-fired power plant with membrane CCS installation are shown. In addition to membrane modules, the CCS installation also consists of two vacuum pumps and two CO2 compressors. In this paper, the relationship between the auxiliary power required to drive these machines and the recoverable amount of heat is shown. This relationship is the reason for the integration of the supercritical coal unit with the CCS installation, which is used for cooling compressed CO2 in the CCS installation by use of condensate (or feed water) from the supercritical coal unit cycle. This cooling process causes both a reduction of the auxiliary power required to drive the compressors and vacuum pumps and increase of power ratio of a steam turbine. In this paper, the optimisation method for minimising the decrease of overall efficiency of the power plant connected with its integration with CCS installation is shown. This results in choosing the optimal pressure ratios in the applied compressors and vacuum pumps under the condition of sufficient heat transmission to the steam turbine cycle. For investigated units, the cost of CO2 emission avoidance and the break-even price of electricity were also calculated. [Copyright &y& Elsevier]

Abstract: Automata theory provides two ways of defining an automaton: either by its transition system, defining its states and events, or by its language, the set of sequences (traces) of events in which it can engage. For many classes of automaton, these forms of definition have been proved equivalent. For example, there is a well-known isomorphism between regular languages and finite deterministic automata. This paper suggests that for (demonically) the non-deterministic automata (as treated in process algebra), the appropriate link between transition systems and languages may be a retraction rather than an isomorphism. A pair of automata, defined in the tradition of CCS by their transition systems, may be compared by a pre-ordering based on some kind of simulation or bisimulation, for example, weak, strong, or barbed. Automata defined in the tradition of CSP are naturally ordered by set inclusion of their languages (often called refinement); variations in ordering arise from different choices of basic event, including for example, refusals and divergences. In both cases, we characterise a theory by its underlying transition system and its choice of ordering. Our treatment is therefore wholly semantic, independent of the syntax and definition of operators of the calculus. We put forward a series of retractions relating the above-mentioned versions of CSP to their corresponding CCS transition models. A retraction is an injection that is (with respect to the chosen ordering) monotonic, increasing and idempotent (up to equivalence). It maps the nodes of a transition system of its source theory to those of a system that has been saturated by additional transitions. Each retraction will be defined by a transition rule, in the style of operational semantics; the proofs use the familiar technique of co-induction, often abbreviated by encoding in the relational calculus. The aim of this paper is to contribute to unification of theories of reactive system programming. More practical benefits may follow. For example, we justify a method to improve the efficiency of model checking based on simulation. Furthermore, we show how model checking of a transition network fits consistently with theorem-proving tools, which reason directly about specifications and designs that are expressed in terms of sets of sequences of observable events. [Copyright &y& Elsevier]

Meeting the Paris Agreement will most likely require the combination of CO 2 capture and biomass in the industrial sector, resulting in net negative emissions. CO 2 capture within the industry has been extensively investigated. However, biomass options have been poorly explored, with literature alluding to technical and economic barriers. In addition, a lack of consistency among studies makes comparing the performance of CO 2 capture and/or biomass use between studies and sectors difficult. These inconsistencies include differences in methodology, system boundaries, level of integration, costs, greenhouse gas intensity of feedstock and energy carriers, and capital cost estimations. Therefore, an integrated evaluation of the techno-economic performance regarding CO 2 capture and biomass use was performed for five energy-intensive industrial sub-sectors. Harmonization results indicate that CO 2 mitigation potentials vary for each sub-sector, resulting in reductions of 1.4–2.7 t CO 2 /t steel (77%–149%), 0.7 t CO 2 /t cement (92%), 0.2 t CO 2 /t crude oil (68%), 1.9 t CO 2 /t pulp (1663%–2548%), and 34.9 t CO 2 /t H 2 (313%). Negative emissions can be reached in the steel, paper and H 2 sectors. Novel bio-based production routes might enable net negative emissions in the cement and (petro)chemical sectors as well. All the above-mentioned potentials can be reached for 100 €/t CO 2 or less. Implementing mitigation options could reduce industrial CO 2 emissions by 10 Gt CO 2 /y by 2050, easily meeting the targets of the 2 °C scenario by the International Energy Agency (1.8 Gt CO 2 /y reduction) for the industrial sector and even the Beyond 2 °C scenario (4.2 Gt CO 2 /y reduction). • Literature review on CO 2 mitigation in steel, cement, chemical, H 2 and paper sectors. • Introduction harmonized methodology to allow comparison between industrial sectors. • All investigated sectors have large reduction potentials for <100 €/t CO 2 avoided. • Negative emissions possible in iron/steel, H 2 and paper sectors. • Potential CO 2 emission reduction of 10 Gt/yr in 2050, easily meeting climate target. [ABSTRACT FROM AUTHOR]

Many of the world's electricity systems are decarbonising, driven in most cases by the deployment of variable renewable energy technologies. This paper studies such systems using generation expansion planning in the form of a linear program to determine and understand least-cost pathways to deep decarbonisation of existing wholesale electricity markets over a 30-year horizon. This work extends previous generation expansion modelling with several, additional options that now enable the substitution of woody biomass for coal and biomethane for natural gas, the retrofit of carbon capture and storage to existing and new build fossil plant, and different constraints on variable renewable energy that differentiate between renewable resource adequacy, system security and economic performance. The most recent, independent, and authoritative technical and financial input data are also used. In all decarbonisation pathways studied, emission reductions are primarily driven by the replacement of the existing coal fleet with utility-scale solar photovoltaic and wind generation. Nonetheless, systematic application of these additional options gives rise to a wide range of different technologies for 'firming' renewable-rich, decarbonised systems, with batteries, pumped hydroelectric energy storage, fossil plant with co-fired biomass and biomethane, carbon capture and storage and nuclear small modular reactors all playing significant roles in different cases. This range of observed pathways is thought to have several implications for system planning, with variable renewable energy tending to be economically competitive up to an imposed technical limit, but with that limit being uncertain and therefore requiring continuous re-evaluation as our understanding evolves. The results of an extensive range of sensitivity studies also suggest that deep decarbonisation is achievable without large increases in costs for consumers, that we should embrace the optionality and competition between different technologies, and that stakeholders have significant choice about non-cost related impacts and preferences, which are manifold. • Generation expansion demonstrates diverse pathways of power system decarbonisation. • ∼90% abatement projected to be achieved via renewables competing solely on cost. • Constraints on VRG integration impact prospects of firm-low carbon technologies. • Additional costs of decarbonisation are relatively insensitive to technology mix. • We should embrace optionality and competition between different technologies. [ABSTRACT FROM AUTHOR]

The use of natural gas for power generation is becoming increasingly important in many regions in the world. Given that the combined cycle gas turbine (CCGT) power stations are lower in capital cost and carbon intensity than their coal-fired counterparts, natural gas fired power stations are considered a vital part of the transition to a low carbon economy. However, CCGTs are not themselves “low carbon” and in order to reach a carbon intensity of less than 50 kg CO 2 /MWh, it will be necessary to decarbonise them via CCS, with post-combustion CCS currently regarded as being a promising technology for this application. In this study, we present a detailed model of a 420 MW triple-pressure reheat CCGT and evaluate its technical and economic performance under full and part load conditions. We evaluate the technical performance of our CCGT model by comparison to an equivalent model implemented in Thermoflow THERMOFLEX and observe agreement of power output and efficiency to within 4.1% and the temperature profile within the HRSG within 2.9%. We further integrate the CCGT with a dynamic model of an amine based CCS process, and observe a reduction in the base plant efficiency from 51.84% at full-load and 50.23% at 60% load by 8.64% points at full-load and 7.93% points at 60% load. A core conclusion of this paper is that CCGT power plants equipped with post-combustion CCS technologies are well suited to dynamic operation, as might be required in an energy system characterised by high penetrations of intermittent renewable power generation. [ABSTRACT FROM AUTHOR]

In this paper, a quadrinomial model based on the theory of real options is developed to evaluate the investment in carbon capture and storage (CCS) retrofitting for existing coal-fired power plants in China. Uncertainties in carbon price, fossil fuel price, investment cost and government subsidy are considered. An existing typical 600 MW supercritical pulverized coal-fired (SCPC) plant is taken as a case study to illustrate the proposed model, and the effects of government subsidy under different scenarios on the critical carbon price to invest in CCS are analyzed. The results indicate that the real options approach has an advantage over the application of traditional net present value (NPV) method when handling uncertainty. And government subsidy has significant effects on reducing critical carbon price for investment in CCS. The critical carbon prices are 103.56 RMB/ton with 100% subsidy and 217.95 RMB/ton without subsidy, while the current average carbon price is 85.2 RMB/ton. This means that the current trading environment is not positive enough to attract investment in CCS retrofitting. These conclusions provide theoretical foundation for decision-making of CCS investment and related policy-making. [ABSTRACT FROM AUTHOR]

In future decarbonization scenarios, CCS with particular reference to post-combustion technologies will be an important option also for energy intensive industries. Nevertheless, today CCS systems are rarely installed due to high energy and cost penalties of current technology based on chemical scrubbing with amine solvent. Therefore, innovative solutions based on new/optimized solvents, sorbents, membranes and new process designs, are R&D priorities. Regarding the CO 2 capture through solid sorbents, a new reactor solution based on rotating fixed beds is presented in this paper. In order to design the innovative system, a suitable CFD model was developed considering also the kinetic capture process. The model was validated with experimental results obtained by the authors in previous research activities, showing a potential reduction of energy penalties respect to current technologies. In the future, the model will be used to identify the control logic of the innovative reactor in order to verify improvements in terms of sorbent exploitation and reduction of system energy consumption. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present article is to conduct an integrated assessment in order to explore whether CCS could be a viable technological option for significantly reducing future CO 2 emissions in China. Methods: In this paper, an integrated approach covering five assessment dimensions is chosen. Each dimension is investigated using specific methods (graphical abstract). Results: The most crucial precondition that must be met is a reliable storage capacity assessment based on site-specific geological data. Our projection of different trends of coal-based power plant capacities up to 2050 ranges between 34 and 221 Gt of CO 2 that may be captured from coal-fired power plants to be built by 2050. If very optimistic assumptions about the country’s CO 2 storage potential are applied, 192 Gt of CO 2 could theoretically be stored as a result of matching these sources with suitable sinks. If a cautious approach is taken, this figure falls to 29 Gt of CO 2 . In practice, this potential will decrease further with the impact of technical, legal, economic and social acceptance factors. Further constraints may be the delayed commercial availability of CCS in China; a significant barrier to achieving the economic viability of CCS due to a currently non-existing nation-wide CO 2 pricing scheme that generates a sufficiently strong price signal; an expected life-cycle reduction rate of the power plant’s greenhouse gas emissions of 59–60%; and an increase in most other negative environmental and social impacts. Conclusion and practice implications: Most experts expect a striking dominance of coal-fired power generation in the country’s electricity sector, even if the recent trend towards a flattened deployment of coal capacity and reduced annual growth rates of coal-fired generation proves to be true in the future. In order to reduce fossil fuel-related CO 2 emissions to a level that would be consistent with the long-term climate protection target of the international community to which China is increasingly committing itself, this option may require the introduction of CCS. However, a precondition for opting for CCS would be finding robust solutions to the constraints highlighted in this article. Furthermore, a comparison with other low-carbon technology options may be useful in drawing completely valid conclusions on the economic, ecological and social viability of CCS in a low-carbon policy environment. The assessment dimensions should be integrated into macro-economic optimisation models by combining qualitative with quantitative modelling, and the flexible operation of CCS power plants should be analysed in view of a possible role of CCS for balancing fluctuating renewable energies. [ABSTRACT FROM AUTHOR]

• Alberta's CO 2 emission from the power and industry sectors is 136 Mtpa. • The total mid CO 2 storage capacity in oil and gas fields in Alberta is 5.2 Gt. • A CCS corridor within 200 km from Edmonton is proposed which will mitigate up to 52 Mtpa CO 2 or 38% of Alberta's CO 2 emission. To enable Alberta, Canada to reduce CO 2 emissions by 30% from 2005 levels by 2030, we investigate carbon capture and storage (CCS) opportunities in Alberta, Canada by conducting a plant-by-plant evaluation of CO 2 emissions from 157 power and industrial plants and a field-by-field analysis of CO 2 storage capacity in 15,143 oil fields and 68,327 gas fields. Results show that CO 2 emissions from power and industrial plants is 136 Mtpa. Additionally, the mid CO 2 storage capacity is 41.5 Gt in gas fields and 5.2 Gt in oil fields. Oil fields also have a mid CO 2 -enhanced oil recovery (CO 2 -EOR) potential of 6,895 MMbbl. Based on these findings, this paper proposes a first-of-a-kind CCS corridor within 200 km from Edmonton, which can mitigate up to 52.4 Mtpa CO 2 or 38% of Alberta's emissions from power and industry sectors. There is a mid CO 2 storage capacity of 1.8 Gt and mid CO 2 -EOR potential of 3,550 MMbbl within this CCS corridor. [ABSTRACT FROM AUTHOR]

It is a big concern in the oil/gas industry that the carbonation-induced corrosion of the concrete-covered steel casing or tubing in underground Carbon Capture and Storage (CCS) may lead to gas leaking and even an environment pollution disaster. To reduce such a safety risk, the carbonation degree of concrete in the CCS project must be detected or monitored, and the corrosion of steel casing/tubing should be inhibited in time. In this paper, Mg was investigated in comparison with Al and Zn in simulated concrete pore solutions (SCPSs) as an intelligent anode that may be used to detect the carbonation degree of concrete and protect the steel in the carbonated concrete. The results showed that Mg could be more sensitively activated and its anodic current efficiency could be improved by carbonation, acting as such a smart anode in carbonated SCPSs. In a practical CCS project, the intelligent detection of the carbonated concrete corrosivity and the protection of the steel casing in the concrete may both be realized by using such a smart Mg anode. While the Zn and Al could not act as a smart sacrificial anode since they were not sensitive to the carbonation and they could not provide sufficient cathodic protection for the steel in the carbonated SCPSs, either. [ABSTRACT FROM AUTHOR]

[Display omitted] • Various robust AI methods were implemented for predicting IFT of CO 2 -brine system. • A comprehensive database including more than 2184 experiment samples was employed for implementing the AI study. • The newly proposed random forest model for predicting IF outperforms the other AI models. Given the current global climate change, renewable energy sources, carbon capture, utilization, and storage (CCUS) are being considered as a potential solutions to this critical global issue. Structural and capillary processes can be used to store carbon dioxide (CO 2) in deep saline aquifers in a way that is safe and does not harm the environment. Due to this fact, the interfacial tension (IFT) of the CO 2 -brine system is an important factor influencing the capacity of storage formations to sequester CO 2. As a result, IFT is essential for conducting a thorough and accurate evaluation in order to determine the optimal strategy for CO 2 storage projects. This paper used intelligent models such as Gaussian Process Regression (GPR), Radial Basis Function (RBF), and Random Forest (RF) to forecast IFT in the CO 2 -brine system with high precision and substantial time saving. The results reveal that the constructed RF model could deliver excellent performance in predicting IFT with the lowest average absolute percent relative error (AAPRE = 1.9156 percent), highest coefficient of determination (R2 = 0.9907), and lowest root mean squared error (RMSE = 0.7279). Furthermore, a sensitivity analysis was performed to ascertain the most critical parameters in the RF model to be considered. The parametric analysis found that both pure and non-pure CO 2 systems had a significant impact on IFT prediction. Also, the RF model was used to assess the structural trapping capacity of a storage location in the Cuu Long Basin. The estimation results obtained in this study agreed perfectly with the previous ones. The findings of this study can aid in a better understanding of how machine learning models can be applied to predict IFT values for the evaluation of the structural CO 2 storage capacity. [ABSTRACT FROM AUTHOR]

Carbon capture and storage technology has the potential to reduce anthropogenic CO 2 emissions. However, the geomechanical response of the reservoir and sealing caprocks must be modelled and monitored to ensure that injected CO 2 is safely stored. To ensure confidence in model results, there is a clear need to develop ways of comparing model predictions with observations from the field. In this paper we develop an approach to simulate microseismic activity induced by injection, which allows us to compare geomechanical model predictions with observed microseismic activity. We apply this method to the In Salah CCS project, Algeria. A geomechanical reconstruction is used to simulate the locations, orientations and sizes of pre-existing fractures in the In Salah reservoir. The initial stress conditions, in combination with a history matched reservoir flow model, are used to determine when and where these fractures exceed Mohr–Coulomb limits, triggering failure. The sizes and orientations of fractures, and the stress conditions thereon, are used to determine the resulting micro-earthquake focal mechanisms and magnitudes. We compare our simulated event population with observations made at In Salah, finding good agreement between model and observations in terms of event locations, rates of seismicity, and event magnitudes. [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]

The long-term energy strategy issued by the German government in 2010 and 2011 embraces a substantial reduction of CO 2 emissions and high shares of renewable energy in electricity production, along with energy efficiency improvements and an accelerated nuclear phase-out. While several studies illustrate scenarios reaching these targets, there are substantial uncertainties pertaining to key assumptions, particularly long-term electricity demand and the large-scale availability of offshore wind and carbon capture and storage (CCS). This paper explores conditions under which model-based scenarios for the German electricity sector comply with the official targets for CO 2 emission reductions and renewable shares. We apply the energy system model LIMES-D, which allows for a joint optimization of generation and transmission capacities. The results indicate that reducing electricity demand plays a crucial role for attaining the government׳s targets. Scenarios for which either offshore wind or CCS is not available show an even stronger need for a decreasing electricity demand to reach the targets and a different pattern of transmission capacity expansion than is the case with full technology availability. Hence, a broad technology portfolio could in turn hedge against future power demand increases that may challenge the joint attainment of the German decarbonization and renewable energy targets. [ABSTRACT FROM AUTHOR]

Amine absorption is a common method for CO 2 removal from flue gas of a power plant. The heat of regeneration, which is usually provided by steam extracted from the power cycle, reduces the power plant efficiency. In this paper, seven configurations of heat pumps integrated with CO 2 capture plant of a natural gas combined cycle (NGCC) power plant were evaluated using HYSYS software. The heat pump provides the regeneration heat as well as processes heating and cooling. Forty-one working fluids were investigated, and the most promising ones were R-141b and NH 3 , with as much as 3.1% savings in the efficiency. When the heat pump cooling and heating capacities were to be considered in the efficiency calculations, the enhancement in efficiency becomes as high as 13.6%. [ABSTRACT FROM AUTHOR]

This paper presents the design and implementation of CD-Form (Clone Detector based on FORmal Methods), a tool targeted at the detection of Type-2 clones in Java code. CD-Form is based on a novel approach for detecting code clones. The methodology adopted performs the analysis on Java bytecode and not on the original Java source. The bytecode is transformed into CCS (Calculus of Communicating Systems) processes, which are successively checked for equivalence. After a thorough description of the methodology used for detecting clones, the design of the tool is presented. The results obtained by evaluating sample Java codes are validated by comparing them to those obtained by a state-of-the-art tool for clone detection. [ABSTRACT FROM AUTHOR]

For large volumes of carbon dioxide (CO 2 ) onshore and offshore transportation, pipeline is considered the preferred method. This paper presents a study of the pipeline network planned in the Humber region of the UK. Steady state process simulation models of the CO 2 transport pipeline network were developed using Aspen HYSYS®. The simulation models were integrated with Aspen Process Economic Analyser® (APEA). In this study, techno-economic evaluations for different options were conducted for the CO 2 compression train and the trunk pipelines respectively. The evaluation results were compared with other published cost models. Optimal options of compression train and trunk pipelines were applied to form an optimal case. The overall cost of CO 2 transport pipeline network was analyzed and compared between the base case and the optimal case. The results show the optimal case has an annual saving of 22.7 M€. For the optimal case, levelized energy and utilities cost is 7.62 €/t-CO 2 , levelized capital cost of trunk pipeline is about 8.11 €/t-CO 2 and levelized capital cost of collecting system is 2.62 €/t- CO 2 . The overall levelized cost of the optimal case was also compared to the result of another project to gain more insights for CO 2 pipeline network design. [ABSTRACT FROM AUTHOR]

The increase in human induced atmospheric CO 2 level leads to an increase in ocean acidification (OA). Mitigation of this increase by storage of CO 2 in abandoned marine oil and gas reservoirs is seen as an interesting cost effective solution. However, this involves a risk of CO 2 loss causing localised reductions in seawater pH. In this paper we report on the effects of CO 2 enhancement on the growth of the bivalve Cerastoderma edule in mesocosms. The experiments show significant reductions in shell length, shell weight and cockle flesh dry weight at increased CO 2 level suggesting both direct (shell erosion) and indirect (metabolic) effects. Indirect effects were analysed and interpreted using a Dynamic Energy Budget model by describing changes in 3 metabolic processes: assimilation, maintenance, and growth. Based on cockle size data only we could not differentiate between these processes, however, by using variability of DEB parameter values in 11 bivalve species, we showed growth to be the least relevant process. [ABSTRACT FROM AUTHOR]

• A bottom-up estimation of CO 2 mitigation potential of combined options for a case-study refinery. • A dynamic CO 2 mitigation potential over time is based on measure interactions for each pathway. • Co-processing account for 60% of the portfolio followed by CCS with 23%, GE with 7%, and H 2 with 6% • The oil and gas industry could reach carbon neutral operation at factory gate. • The methodological approach brings insights to define optimal transition routes of the industry. The oil and gas industry is responsible for 6% of total global CO 2 emissions, from exploration to downstream petrochemical production and account for another 50% when including the use of its products. Thus, this industry has a significant role in realising the target of net "zero" CO 2 emissions by 2070, essential to limit global warming to 1.8 °C [2], as introduced under the Paris agreement. Currently, the interactions of an extensive set of individual and combined CO 2 mitigation measures along the value chain and over time are poorly assessed. This paper aims to assess a bottom-up CO 2 mitigation potential for a complex refinery, including portfolios of combined mitigation options, considering synergies, overlap, and interactions over time for more realistic insight into the costs and constraints of the mitigation portfolio. A total of 40 measures were identified, covering a wide range of technologies such as energy efficiency measures (EEM), carbon capture and storage (CCS), bio-oil co-processing, blue and green hydrogen (BH 2 , GH 2), green electricity import, and electrification of refining processes linked to the transition of the Colombian energy systems. Five deployment pathways were assessed to achieve different specific targets: 1-base case scenario, 2-less effort, 3-maximum CO 2 avoidance, 4-INDC, and 5-measures below 200 €/t CO 2. Two scenarios (3 and 5) gave the highest GHG emission reduction potentials of 106% and 98% of refining process emissions, respectively. Although significant, it represent only around 13% of the life-cycle emissions when including upstream and final-use emissions of the produced fuels. Bio-oil co-processing options account for around 60% of the mitigation options portfolio, followed by CCS (23%), green electricity (7%) and green H 2 (6%). The devised methodological approach in this study can also be applied to assess other energy-intensive industrial complexes and shed light on the bias for estimating CO 2 mitigation potentials, especially when combining different mitigation options. This is turn is vital to define optimal transition pathways of industrial complexes. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper reports on a comparative performance assessment of USC and IGCC plants. [•] Both plants are also integrated with low temperature CO2 capture/compression sections. [•] The USC plant is integrated with a SNOX system for gas purification. [•] USC plant provides, in its basic configuration, better performance than the IGCC plant. [•] IGCC plant shows lower energy penalties when integrated with the CO2 removal section. [Copyright &y& Elsevier]

The process chain for Carbon Capture and Sequestration (CCS) includes tubing for injection of CO2 into saline aquifers. The compressed CO2 is likely to contain specific impurities; small concentrations of SO2and NO2 in combination with oxygen and humidity are most harmful. In addition, CO2 saturated brine is supposed to rise in the well when the injection process is interrupted. The material selection has to ensure that neither CO2 nor brine or a combination of both will leak out of the inner tubing. In this comprehensive paper the investigated materials range from low-alloy steels and 13% Cr steels up to high-alloy materials. Electrochemical tests as well as long term exposure tests were performed in CO2, in brine and combination of both; pressure was up to 100 bar, temperature up to 60 °C. Whereas the CO2 stream itself can be handled using low alloy steels, combinations of CO2 and brine require more resistant materials to control the strong tendency to pitting corrosion. The corrosion behavior of heat-treated steels depends on factors such as microstructure and carbon content. For different sections of the injection tube, appropriate materials should be used to guarantee safety and consider cost effectiveness. [ABSTRACT FROM AUTHOR]

This paper presents a risk assessment methodology for high-pressure CO2 pipelines developed at the Health and Safety Laboratory as part of the EU FP7 project CO2Pipehaz. Traditionally, consequence modelling of dense gas releases from pipelines at major hazard impact levels is performed using integral models with limited or no consideration being given to weather bias or topographical features of the surrounding terrain. Whilst dispersion modelling of CO2 releases from pipelines using three-dimensional CFD models may provide higher levels of confidence in the predicted behaviour of the cloud, the use of such models is resource-intensive and usually impracticable. An alternative is to use more computationally efficient shallow layer or Lagrangian dispersion models that are able to account for the effects of topography whilst generating results within a reasonably short time frame. In the present work, the proposed risk assessment methodology for CO2 pipelines is demonstrated using a shallowlayer dispersion model to generate contours from a sequence of release points along the pipeline. The simulations use realistic terrain taken from UK topographical data. Individual and societal risk levels in the vicinity of the pipeline are calculated using the Health and Safety Laboratory's risk assessment toot QuickRisk. Currently, the source term for a CO2 release is not well understood because of its complex thermodynamic properties and its tendency to form solid particles under specific pressure and temperature conditions. This is a key knowledge gap and any subsequent dispersion modelling, particularly when including topography, may be affected by the accuracy of the source term. [ABSTRACT FROM AUTHOR]

This paper presents a risk assessment methodology for high pressure CO2 pipelines developed at the Health and Safety Laboratory (HSL) as part of the EU FP7 CO2Pipehaz project. Until recently, risk assessment of dense phase and supercritical CO2 pipelines has been problematic because of the lack of suitable source term and integral consequence models that handle the complex behaviour of CO2 appropriately. The risk assessment presented uses Phast, a commercially available source term and dispersion model that has been recently updated to handle the effects of solid CO2. A test case pipeline was input to Phast and dispersion footprints to different levels of harm (dangerous toxic load and probit values) were obtained for a set of pipeline specific scenarios. HSL's risk assessment tool QuickRisk was then used to calculate the individual and societal risk surrounding the pipeline. Knowledge gaps that were encountered such as: harm criteria, failure rates and release scenarios were identified and are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Carbon capture and storage (CCS) technology, which has been considering one of the effective carbon reduction options, is induced in the self-constructed aggregated economic technological model in this paper, and the development potential of CCS under the given climate policies is depicted. We explore the most cost-effective way of targeted CO2 abatement to reach specific climate stabilization targets by comparing the climate policies including subsidies for alternative energy, tax for fossil fuel and a combination of both. We also investigate the impacts of these policy instruments on the energy demand, consumptions, R&D activities and the performances of various carbon-free energy technologies. The main findings are as follows: first, the subsidy policy alone never offers the cheapest option to meet the reduction targets, and the policy of carbon tax is proved to be the most cost-effective way of CO2 abatement. Second, subsidy plays a limit role in promoting R&D activities of non-carbon technologies, which are driven more by the mix policy. Third, we find that the implementation of carbon tax will largely promote the development of CCS, and the share of fossil technology equipped with CCS in total will have reached around 15% by the end of 21 century. Finally, the CO2 reduction ratio for CCS keeps increasing in the present of carbon tax, and pathway of carbon abatement contribution for CCS is hump-shaped when turning to the mix policy case. [Copyright &y& Elsevier]