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Mitigation of climate change by reducing the anthropogenic CO2 emissions has recently gained huge momentum. A prime pathway to achieve it in the short-medium term lies within capturing CO2 from industries’ flue gases. Post-combustion CO2 capture (PCC) is the most mature methodology for large-scale CO2 capture and closest to market. However, the conventional chemical absorption-based PCC process implies high regeneration energy requirements, constituting the majority of the energy load when adding PCC to the plant from which the CO2 is going to be captured. As such, reducing the overall parasitic load of the conventional process is of interest. Changing the solvent or improving the process flowsheet are two main methodologies to achieve higher energetic efficiency and lower exergy losses. As there are several reviews dealing with novel solvents, this review critically evaluates the progress in improving the conventional PCC process through modifications of process configurations and shadowed by solvent replacements as drop-in solutions. The process configurations were grouped into absorption and stripping enhancement categories. A comparative analysis was conducted between the different available schemes in the literature and interactions between solvents and process configurations were showcased, highlighting the advantages and shortcomings of some of them. The review reveals the need for standardized framework and optimization algorithms using exergo-economic performance indicators for integrated solvent and process synthesis.

In the present work, steady-state simulations of the natural gas combined cycle (NGCC) and the post-combustion CO2 capture (PCC) processes have been modelled in Aspen Plus® environment. The capture plan model was validated with data from the Colombian power plant "Termocentro" at 300MWe. A techno-economical evaluation study has been performed for both a combined cycle (gas and steam) and the PCC process. The PCC process was based on the solvent 30% (w/w) MEA-H2O and on the solvent H2O-30% (w/w)-MEA-5% (w/w))-[Bmim][Bf4]. Sensitivity analysis was carried out, giving as a result an optimum concentration of 5% (w/w) for the 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid ([Bmim] [BF4]) solvent. The study indicates how with efficient operation conditions of solvent regeneration, [Bmim][Bf4] may be used for CO2 capture plans on the future.

In a nickel-producing multiple hearth furnace, there is a problem associated to the automatic operation of the temperature control loops in two of the hearths, since the same flow of air is split into two branches. A neural model of the post-combustion sub-process is built and served to increase the process efficiency of the industrial furnace. Data was taken for a three-months operating time period to identify the main variables characterizing the process and a model of multilayer perceptron type is built. For the validation of this model, process data from a four-months operating time period in 2018 was used and prediction errors based on a measure of closeness in terms of a mean square error criterion measured through its weights for the temperature of two of the hearths (four and six) versus the air flow to these hearths. Based on a rigorous testing and analysis of the process, the model is capable of predicting the temperature of hearth four and six with errors of 0.6 and 0.3 °C, respectively. In addition, the emissions by high concentration of carbon monoxide in the exhaust gases are reduced, thus contributing to the health of the ecosystem.

© Copyright © 2020 Gulec, Meredith and Snape. Heavy industries including cement, iron and steel, oil refining, and petrochemicals are collectively responsible for about 22% of global CO2 emissions. Among these industries, oil refineries account for 4–6%, of which typically 25–35% arise from the regenerators in Fluid Catalytic Cracking (FCC) units. This article reviews the progress in applying CO2 capture technologies to FCC units. Post combustion and oxyfuel combustion have been investigated to mitigate CO2 emissions in FCC and, more recently, Chemical Looping Combustion (CLC) has received attention. Post combustion capture can readily be deployed to the flue gas in FCC units and oxyfuel combustion, which requires air separation has been investigated in a pilot-scale unit by Petrobras (Brazil). However, in comparison, CLC offers considerably lower energy penalties. The applicability of CLC for FCC has also been experimentally investigated at a lab-scale. As a result, the studies demonstrated highly promising CO2 capture capacities for FCC with the application of post combustion (85–90%), oxyfuel combustion (90–100%) and CLC (90–96%). Therefore, the method having lowest energy penalty and CO2 avoided cost is highly important for the next generation of FCC units to optimize CO2 capture. The energy penalty was calculated as 3.1–4.2 GJ/t CO2 with an avoiding cost of 75–110 €/t CO2 for the application of post combustion capture to FCC. However, the application of oxyfuel combustion provided lower energy penalty of 1.8–2.5 GJ/t CO2, and lower CO2 avoided cost of 55–85 €/t CO2. More recently, lab-scale experiments demonstrated that the application of CLC to FCC demonstrate significant progress with an indicative much lower energy penalty of ca. 0.2 GJ/t CO2.

An extensive evaluation on a modern full-scale municipal solid waste incineration system was conducted for characterizing the distribution of highly toxic chlorinated aromatics, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs), and their corresponding mass fluxes in post combustion zone. It was found that the flue gas/fly ash partitioning behaviors of chlorinated aromatics could be essentially described by their octanol-air partition coefficients (KOA) and strongly affected by the flue gas temperature. Above 93% of chlorinated aromatics formed in boiler section was partitioned into the flue gas and transported into the subsequent flue gas cleaning system, in which above 92% of Cl3–8DDs, Cl3–7DFs, Cl5–10Bs and Cl4–8Ns in flue gas was removed by the discharge of fly ash. The results of mass flux calculation indicated that the memory effect in flue gas cleaning system remarkably elevated the emission levels of chlorinated aromatics, especially the less chlorinated ones. The memory effect should mainly result from the direct chlorination mechanism mediated by the deposited particles. In addition, activated carbon injection could cause an obvious increase in PCBs emission. The obtained results provided some important implications for further reducing the emission of highly toxic chlorinated aromatics.

The energy in general and electricity, in particular, plays a key role in the development of any nation. In India, about 60% of electricity demand is fulfilled by coal-based power plants. Increasing CO2 concentration in the environment is a global problem for which coal-based power plants are the main contributors. The present study is focused on the energy and exergy-based thermodynamic analysis of a 500 MWe Subcritical thermal power plant with Monoethanolamine (MEA) based post-combustion CO2 capture. The study is further carried out by using solar energy for reducing the energy penalty against MEA regeneration. A computer software program “Cycle-Tempo” is used for simulating the plants. The study reveals that use of solar energy for MEA regeneration instead of using steam increases the plant energy and exergy efficiencies about 2.4% and 5.4% points, respectively. The CO2 avoided by the plant is 0.71 kg/kWh. The total solar collector area required is about 347.6 acres.

The implementation of carbon capture, use, and storage in the cement industry is a necessity, not an option, if the climate targets are to be met. Although no capture technology has reached commercial scale demonstration in the cement sector yet, much progress has been made in the last decade. This work intends to provide a general overview of the CO2 capture technologies that have been evaluated so far in the cement industry at the pilot scale, and also about the current plans for future commercial demonstration., S.M. acknowledges the award of an Introduction to Research fellowship (grant number: JAEICU-19-INCAR-26) from the JAE Intro ICUs Programme of the Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC). M.G.P. acknowledges support from the Ramon y Cajal Programme (grant number: RyC-2015-17516) of the Government of Spain, co-financed by the European Social Fund. Financial support from the Government of the Principado de Asturias (PCTI, grant number: IDI/2018/000115), co-financed by the European Regional Development Fund (ERDF), is also acknowledged.

Post-combination NOx reduction technique in biodiesel involves control techniques after combustion. Biodiesel fuel processes similar properties to fossil diesel with many unique characteristics of combustion, which require critical consideration in current CI engines. Due to continued research in biodiesel NOx emissions, there are a number of post-treatment techniques that have been made available. These techniques include SCR, SNCR, NAC and lean NOX. These techniques operate as potentials for emission reduction in the transport sector in two or more combinations. Regulated emissions cannot be controlled or reduced with one technique only. Instead, a multi-approach strategy needs consideration by component manufacturers and automobile industry stakeholders. In other words, this chapter will evaluate post-combustion strategies, which can effectively lead to reduction in emissions from the transport sector. Secondly, this chapter will discuss latest research and development in post-combustion control and emission reduction strategies with the use of biodiesel as alternative fuel.

Heat consumption is a major concern for the development of the post-combustion CO2 capture in thermal power plants. In this work, a mathematical model is implemented to minimize the heat duty for a conventional post-combustion CO2 capture process. An explicit three-parameter vapor-liquid equilibrium (VLE) model is developed. In the VLE model, the solvent is characterized by the absorption heat, indexes for cyclic capacity and absorption capacity. The configuration of these properties is based on typical commercially available solvents. The minimal heat consumption of the optimal solvent is 2.44 MJ/kmol CO2, which is 70 percent of the conventional MEA solvent. Besides, the match relationship between the absorption heat and lean solvent loading is investigated from the view of balance between absorption and regeneration processes.

Adsorption-based post-combustion CO2 capture is enjoying significant research attention due to its potential for significant reductions in energy penalty, cost and environmental impact. Recent sorbent development work has focussed on polyethyleneimine (PEI) and dry sorbents that exhibit attractively low regeneration energy requirements. The main objective of this study is to identify best suitable sorbent for the recently published swing adsorption reactor cluster (SARC) concept. The screening results of four sorbents indicated two PEI sorbents to be good candidates for SARC application: a PEI sorbent functionalized with 1,2-epoxybutane supported on silica (referred to as EB-PEI in the rest of the document) and a PEI sorbent supported on mesoporous silica containing confined metal organic framework nanocrystals (referred to as PEI-MOF in the rest of the document). High resolution single-component isotherms revealed substantial differences in adsorption capacity and optimal operating temperatures for the two PEI sorbents, and CO2 and H2O isotherm models were derived from this data. Subsequently, breakthrough experiments and lab-scale reactor tests showed that co-feeding of CO2 and H2O had no significant effect, allowing the single-component isotherm models to be safely used in large-scale reactor simulations. Such a reactor model was then employed to illustrate the effect of the sorbent adsorption characteristics on the efficiency of the novel swing adsorption reactor cluster, which combines pressure and temperature swings. The EB-PEI and PEI-MOF sorbents were compared to a previously published PEI sorbent with distinctly different adsorption behaviour and recommendations for future sorbent development work were made. This article is available under the Creative Commons CC-BY-NC-ND license and permits non-commercial use of the work as published, without adaptation or alteration provided the work is fully attributed.

CO2 capture performance of 50 wt.% K2CO3/alumina was investigated using various types of alumina supports such as γ-Alumina, Boehmite and Aerogel. Physical mixing and incipient wetness impregnation were used for preparing sorbents. Physically mixed K2CO3/γ-Alumina was the most efficient sorbent, with a maximum CO2 capture capacity of 5.5 mmol CO2/g K2CO3. γ-Alumina displayed the lowest, and Aerogel the highest, hydrophilicity and surface area. Increasing hydrophilicity and surface area also increased water adsorption capacity, which adversely affected the CO2 capture capacity of the physically mixed sorbents. The excess water adsorption capacity converted K2CO3 to an almost inactive precursor of K2CO3·1·5H2O. BET and SEM results showed that recrystallization of K2CO3 from water had an adverse impact on the physical structure of the impregnated sorbents which affected their CO2 capture performance. The kinetic behavior of the samples was analyzed using the Avrami kinetic model. K2CO3/γ-Alumina prepared by physical mixing and impregnation methods showed the highest carbonation rates with K-values of 0.1168 and 0.2260, and n-values of 1.1257 and 1.2004, respectively. K2CO3/Aerogel and K2CO3/Boehmite prepared by the physical mixing method exhibited higher performance than the respective impregnated sorbents in terms of carbonation rate and CO2 capture capacity.

An adsorbent for post-combustion carbon dioxide capture was prepared using low-cost and sustainable natural zeolite coated with chitosan. An optimum adsorbent was identified from 3 levels of particle size of natural zeolite and 10 levels of chitosan loading. The optimum adsorbent was characterized using infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis and differential scanning calorimetry. The chemical and thermal properties of the adsorbent indicated successful coating of chitosan on natural zeolite. The adsorbent registered competitive dynamic adsorption capacity of 0.81 mmol g-1 with good retention, at least, up to 5 adsorption-desorption cycles.

This study investigated the absorption heat, equilibrium CO2 solubility, absorption and desorption rates, cyclic capacities, heat duty, and absorption kinetic modeling of amine blends containing AMP and DETA. The AMP and DETA concentrations were varied (1–2.5 kmol/m3 and 0.5–2 kmol/m3, respectively) while the total amine concentration was constant at 3 kmol/m3. The absorption experiment was conducted at 15 %v/v CO2 and 313 K while the desorption temperature was at 363 K. Experimental results revealed that the absorption rates, cyclic capacities and desorption rates of some AMP–DETA blends were higher than those of 5 kmol/m3 MEA. The absorption heat of the blends is comparable to that of MEA while the heat duty of some AMP–DETA blends are much lower than that of 5 kmol/m3 MEA. The optimal amine blend was confirmed to be 2 kmol/m3 AMP – 1 kmol/m3 DETA. A model similar to the power law kinetic model showed that CO2 composition in the feed gas affected the initial absorption rates as compared to AMP/DETA molar concentration ratio. The model predicted the initial absorption rate with a %AAD of 0.52%. These results provide good prospects for AMP–DETA blends towards CO2 capture.

It is typical to assume that the capture system operates at the full working load of the power plant. This study aims to develop systematic design framework which can provide a cost-effective strategy for operating CO 2 capture plant under different operating load. The part-load performance of CO 2 capture process together with power plant is modeled and evaluated with a process simulator UniSim ® . This study considers both natural gas-fired combined cycle (NGCC) and coal-fired plants, in which optimization is carried out for finding an economic operating strategy to minimize regeneration energy without compromising process efficiency of the capture system. The multi-period modeling approach is applied to accommodate discontinuous nature of part-load performance, with which techno-economic impacts of part-load operation is investigated in a holistic manner. The case study is presented to demonstrate the usefulness of proposed design and optimization framework and to provide practical guidelines and conceptual insights for part-load operation in practice. From the case study, the specific reboiler duty is reduced through the superstructure optimization at full-load operation, which is about 3% lower than one without structural modifications. Also, the operational optimization for part-load achieves energy savings by 2–3% in NGCC and 3–5% in coal-fired power plant.

This work presents a mathematical modeling framework for the simulation and optimization of pressure/vacuum swing adsorption (P/VSA) processes for post-combustion CO 2 capture. A single-stage P/VSA process for CO 2 capture from dry flue gas is considered using new zeolite 13X-based adsorbents resulting from perturbation on the 13X zeolite isotherm. A two-bed six-step P/VSA cycle configuration with light product pressurization is employed in systematic simulation and optimization studies. First a zeolite 13X, the current benchmark commercial adsorbent for CO 2 capture, is considered. Accordingly, the model is used to study and evaluate new zeolite 13X-based adsorbents for more efficient CO 2 capture. The results from systematic comparative simulation studies demonstrate that a modified zeolite 13X-based adsorbent appears to have better process performance compared with the original zeolite 13X. Furthermore, process optimization studies employing the above potential adsorbents are performed to minimize energy consumption for specified minimum requirements in CO 2 purity and recovery. The optimization results indicate that the minimum target of 95% in CO 2 purity and 90% in CO 2 recovery is easily met for the P/VSA process under consideration for both potential adsorbents under different operating conditions resulting in different energy requirements and CO 2 productivity.

This study investigated the effect of particle size and chitosan loading on the performance of chitosan-coated natural zeolite adsorbent in post-combustion carbon dioxide capture. The adsorbents were prepared in 3 levels of average particle size (0.75 mm, 1.5 mm and 2 mm) of natural zeolite and 4 levels of chitosan loading (0, 15, 30 and 45 wt% of natural zeolite) using a simple coating procedure. The adsorbents were characterized using infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis, and differential scanning calorimetry. The capture performance of the adsorbent was measured in terms of breakthrough time. The change in chemical properties, surface morphology and thermal characteristics of natural zeolite confirms the successful coating of chitosan. The mean breakthrough time increases with decreasing particle size and increasing chitosan loading up to 15 wt% of natural zeolite.

Amine-based post-combustion CO 2 capture (PCCC) technology is regarded as one of the most viable solutions for the mitigation of CO 2 emissions. It has been mature enough to be implemented on commercial scales. However, N- nitrosamines and N- nitramines can be formed as by-products of amine degradation during PCCC processes. They are suspected carcinogens and strictly regulated. With the development of PCCC technology across the global, PCCC facility may become a main source of N- nitrosamines and N- nitramines to the environment. Due to the possible adverse effects of N- nitrosamines and N- nitramines on the environment and human health, the interests in the occurrence, fate and mitigation of PCCC-derived N- nitrosamines and N- nitramines have been shared by a growing number of researchers recently. Therefore, this article provides a comprehensive review on the most recent efforts in this emerging field. In detail, this review focuses on (a) the formation, emission and degradation of N- nitrosamines and N- nitramines from amine-based PCCC processes, (b) the toxicology and environmental impact of PCCC-derived N- nitrosamines and N- nitramines, (c) the methods to destruct and remove N- nitrosamines and N- nitramines from PCCC waste, and (d) the future research perspectives.

The reduction of CO2 emissions has become a challenge due to rapid economic growth all over the world. Growing concerns on this issue have led the researcher to develop and implement several strategies including one very promising strategy involving CO2 capture from power plants. This paper presents a Computer Aided Molecular Design (CAMD) technique to design new alternative solvents as replacements for commonly used solvents during the post combustion carbon capture process in power plants, which is often costly and energy intensive. The CAMD technique can quickly identify the most suitable solvents and avoid spending resources on infeasible solvent replacements. In this study, the reverse design approach is used where, first, the criteria of the targeted solvents are identified and then the desired solvent candidates generated. The methods for this work consists of five steps: 1) Problem formulation, 2) Generation of single reactive solvent candidate using ProCAMD tools in ICAS software, 3) Prediction of the reaction mechanism between the potential amine solvent candidate and CO2 using the zwitterion mechanism and base-catalysed hydration mechanism, 4) Evaluation of process performance by calculating the heat required for the solvent regeneration process, and 5) Selection of the best solvent candidate based on its desired process performance. The result of this study reveals that 25 amine-based solvents for the chemical absorption process were successfully generated from the amine and alcohol functional groups. By using the proposed solvent, significant savings on regeneration energy, up to 31.4%, could be achieved compared to the conventional solvent, MEA. The percentage average absolute deviation (AAD) of the property prediction model that this study used to estimate the value of heat of formation is 4.67%. This finding is important to further reduce the regeneration energy, which makes the CO2 capture process costly, and achieve a more sustainable and cleaner environment.

The aim of the work is to carry out an economic assessment of the effect of various structures of multi-tiered oxygen lances and methods for flushing the converter bath with the afterburning of waste gases on the efficiency of the production of iron-carbon semi-products in a modern metallurgical plant. The study was conducted for the process of steel smelting in converters of combined blowing with supply of oxygen from above and neutral gas through the bottom in the conditions of using conventional and multi-tiered oxygen tuyeres. Studies on the afterburning of converter gas in the converter cavity showed that, in proportion to the increase in the proportion of CO2 in the exhaust gases, the costs of steel production are reduced. Compared with the use of tuyeres of classical construction, they amount to 3.23 US dollars / ton of steel for double-circuit, 6.81 US dollars / ton of steel for bunk, and 11.61 US dollars / ton of steel for three-tier. It was determined that when using the classic design of the upper oxygen tuyere, the lower heat of combustion of the converter gas is 10 MJ / m3. In comparison with the classical design, the two-tier, double-circuit and three-tier tuyeres ensure a reduction in the lower heat of combustion of the converter gas by 8,5; 4.4 and 27.1% (rel.), Respectively. On the basis of the data obtained, it is possible to draw a conclusion about the effectiveness of using the technology of combined blowing of the converter bath with the afterburning of exhaust gases in the converter cavity.

A new and robust generation-2 light-responsive MOF with UiO-66 topology applicable for post combustion CO2 capture has been successfully synthesized and is described in this article. Azo-UiO-66 shows a satisfactory performance for CO2/N2 separation as observed through high CO2/N2 selectivity. Furthermore, due to the presence of azobenzene groups, Azo-UiO-66 also exhibits a very efficient CO2 photoswitching uptake, a characteristic that has never been observed in any generation-2 light-responsive MOF. Combined together with its robust character, this makes Azo-UiO-66 a promising candidate for highly selective and low energy CO2 capture applications. To further apply this material, Azo-UiO-66 was incorporated in Matrimid to form mixed matrix membranes (MMM). Composites with up to 20 wt% of Azo-UiO-66 were fabricated and tested. The resulting MMM showed increased performance in terms of CO2 permeability and CO2/N2 selectivity compared with the similar MOF-based MMM composites. This then shows another promising application of Azo-UiO-66 as a filler to enhance polymeric membrane performance for CO2 separation.

Solid-state synthesis ensures a high loading and well-dispersed growth of a large collection of metal–organic framework (MOF) nanostructures within a series of commercially available mesoporous silica. This approach provides a general, highly efficient, scalable, environmentally friendly, and inexpensive strategy for shaping MOFs into a fluidized form, thereby allowing their application in fluidized-bed reactors for diverse applications, such as CO2 capture from post-combustion flue gas. A collection of polyamine-impregnated MOF/SiO2 hybrid sorbents were evaluated for CO2 capture under simulated flue gas conditions in a packed-bed reactor. Hybrid sorbents containing a moderate loading of (Zn)ZIF-8 are the most promising sorbents in terms of CO2 adsorption capacity and long-term stability (up to 250 cycles in the presence of contaminants: SO2, NOx and H2S) and were successfully prepared at the kilogram scale. These hybrid sorbents demonstrated excellent fluidizability and performance under the relevant process conditions in a visual fluidized-bed reactor. Moreover, a biochemically inspired strategy for covalently linking polyamines to MOF/SiO2 through strong phosphine bonds has been first introduced in this work as a powerful and highly versatile post-synthesis modification for MOF chemistry, thus providing a novel alternative towards more stable CO2 solid sorbents.

Amino-MIL-101(Fe) was synthesized and assessed for post-combustion CO2 capture. A hybrid model has been applied which resulted in better agreement with the experimental data. The achieved adsorption values for the pure CO2 and N2 gases at 1 bar and 298 K were equal to 0.41 and 0.33 mmol.g−1. The kinetic modeling of adsorption data indicated that the adsorption of CO2 and N2 at low pressure was not kinetically controlled. The adsorption selectivity of CO2 over N2 was estimated using IAST, which was achieved equal to 1.6.

A superstructure-based optimisation model for the CO2 capture process using an N2-selective and CO2-selective membranes is presented. The model automatically selects either of the membranes for each membrane stage to have a hybrid membrane CO2 capture process. The superstructure embeds numerous process routes and allows the collection of product streams and residue streams from either the retentate side or permeate side of the multi-membrane stages. This results in novel process flowsheets for post-combustion CO2 capture using membrane technology. In the study, the optimisation of carbon capture by an all N2-selective membrane process is also carried out. At 90% recovery and 95% product purity, the multi-stage optimisation of the N2–CO2 hybrid membrane process reduces the total membrane area by 46% and the cost of capture by 14% compared to the optimised CO2-selective membrane process.

Large-scale CO2 abatement is key to avoid the detrimental environmental impacts of increased CO2 emissions worldwide. Solvent-based absorption is a mature post-combustion capture technology for short- to medium-term implementation. However, high energetic requirements, capture costs and technical challenges have been prohibiting its wide industrial deployment. Extensive research efforts have enabled significant improvements that resulted in scaling-up of pilot plants to industrial-level systems and commercial installations. This work provides a detailed review of these activities for plants of different capacities in 37 locations worldwide. The presented information pertains to: a) baseline, packed bed, absorption/desorption flowsheets, originally developed for alkanolamines, b) flowsheets with significant structural modifications that increase the operating driving forces, c) flowsheets including modifications for phase-change solvents and d) flowsheets that incorporate rotating packed beds (RPB). Technical details are presented regarding tested solvents, energetic performance, operating conditions, types and capacity of equipment, emissions, degradation and corrosion. It is observed that energy recovery in the stripper enables significant regeneration energy reduction, as proven in a commercial-scale plant. Equivalent performance has also been achieved with the chilled ammonia process in large-scale pilots. Liquid-liquid phase-change solvents and RPBs exhibit high potential for operating and capital expenditure reductions, but require significant scaling-up effort. Research in RPBs includes mainly lab-scale, mass transfer investigations. Several large-scale plants are being developed in China.

Membrane technology is a promising strategy in flue gas CO2 capture. Recently, many high-performance multilayer composite membranes for CO2/N2 separation were successfully developed in the laboratory. However, the detailed scaling-up processes were rarely discussed due to the lack of mature technology and equipment that specially designed for the proven advanced membrane materials. This study investigated the large-scale production of the defect-free thin multilayer composite membrane for flue gas CO2 capture. A novel coating machine with double blades and surface cross-linking unit was designed, and the industrial scale multilayer composite membranes were prepared by running the coating machine twice. The coating solution stability of intermediate layer solution was prolonged to more than 72 h. The key technologic parameters including web speed and the concentration of cross-linking unit were analyzed. The continuously prepared multilayer composite membrane shows high and stable CO2/N2 performance and great potential in the application of flue gas CO2 capture.

As a promising alternative, polyethyleneimine-functionalized silica (PEI/SiO2) is investigated extensively for post-combustion CO2 capture from flue gas to alleviate the global fossil-related CO2 emissions, with the superiority of prominent adsorption capacity, selectivity, and regeneration performance. However, significant concerns of the trace acid impurities (SO2 and NOx) coexisted in flue gas have arisen, due to the potential interference on the stability of PEI/SiO2 in the long-term operation. To identify the effects of different acid impurities on CO2 capture performance, herein, we explored the behavior of PEI/SiO2 on exposure to various simulated flue gases containing single or multiple acid impurities, and the poisoning effects of SO2 and NO2 were revealed, which would result in the drastic losses of capacity. Similarly, in the continuous adsorption-regeneration cycles, the working capacities were linearly decreased by 39.8% and 19.2% in the presence of SO2 and NO2, respectively, ascribed to their strong affinity toward amines. In contrast, the adsorbent treated by NO could still maintain a stable performance, and the synergetic effects proved to be not significant, considering co-existence of multiple impurities. Additionally, the interference was demonstrated in detail to be associated with the irreversible binding of SO2 and NO2 with amines, and the formation of some induced species, which gradually occupied the available amine sites, would lead to the degradation of PEI/SiO2 upon exposure to acid impurities in the flue gas.

Solvent-based post-combustion carbon capture (PCC) process is widely viewed as the most viable option for reducing CO2 emission. This technology has been deployed globally and many researches have been conducted in this area. In this paper, current status of dynamic modelling, system identification and control scheme of solvent-based PCC process is reviewed. Different research directions of these areas are discussed to conclude the existing challenges. Based on this, this paper is also trying to provide potential solutions as possible pathways for flexible and economical operation.

The absorption/desorption performance of carbon dioxide (CO2) in aqueous 5 M monoethanolamine (MEA) solutions in the presence of various solution regeneration promoters was comprehensively investig...