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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]

• 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]

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]

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 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]

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]

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]

• 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]

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]

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: This work reviews the advantages and disadvantages of using mineral wastes for CCS and their potential in CO2 abatement, highlighting the potential applications and scenarios. This study indicates that a variety of inorganic waste materials such as pulverised fuel ash, municipal solid waste ash, cement kiln dust, biomass and paper sludge ash and sewage sludge ash are available feedstocks for Carbon Capture and Storage by Mineralisation (CCSM) in the UK. The high variability of both the waste amounts and chemical composition represent a major obstacle to the deployment of these materials in CCSM. Currently, mineral waste resources for mineral carbonation have the theoretical potential to capture about 1Mt/year CO2 in the UK, considering only the materials not recycled that are currently sent to landfill. Moreover, inorganic waste as a CCSM resource is in many ways more complex than the use of natural minerals due to uncertainty on future availability and high chemical variability and might be viable only in niche applications. For example, the use of inorganic wastes (concrete waste and steel slag) and buffer solutions in spray trickle bed systems (able to sequester 50% of the CO2 entering the system) was estimated to have costs competitive with geological storage. [Copyright &y& Elsevier]

• Developed life cycle assessment model for biomass co-firing power plants with CCS. • Given detailed process-level input-output table based on mass and energy balances. • Co-firing of 25% biomass with coal can achieve near-zero emissions in CCS plants. • Environmental burden shifts significantly as the co-firing ratio. • Uncertainty analysis was carried out for the environmental burden shift. As a carbon-neutral renewable energy source, biomass co-firing with coal contributes to reducing the carbon intensity of pulverized coal power plants with CO 2 capture and storage; thus, this process significantly reduces the greenhouse gas emissions of the power industry. However, various types of environmental impacts caused by co-firing have hindered the large-scale deployment of this technology. In this study, ten life cycle assessment models were developed based on the Integrated Environmental Control Model and GaBi software to quantify the performance parameters of different power plants and the influence of the co-firing ratio on various environmental impact categories. The system boundaries included raw material acquisition, raw material transport, energy conversion of power plants, CCS and brine treatment. The results indicated that a pulverized biomass/coal co-firing power plant with CCS can achieve near-zero emissions at a co-firing ratio of 25% and negative emissions of 877 kg CO 2 -e/MWh from a life-cycle perspective when coal is totally replaced. Co-firing biomass and coal in power plants has a passive impact on seven environmental categories, such as the eutrophication potential and toxicity potential, rather than on the global warming potential, abiotic resource depletion potential and acidification potential. The major causes of environmental burden shifting are energy penalties and indirect emissions from high-energy-consumption processes, especially emissions of N 2 O, NH 3 and ethylene oxide released during biomass extraction and solvent preparation. The conclusions and recommendations presented in this paper may have implications for deep decarbonization in other industrial sectors. [ABSTRACT FROM AUTHOR]