Greenhouse Gases: Science and Technology最新文献

Carbon dioxide (CO₂) capture technologies are crucial for mitigating climate change, with post-combustion capture (PCC) using chemical absorption being a leading method. However, the energy-intensive solvent regeneration process presents a significant challenge, consuming up to 50% of the total energy in carbon sequestration. Despite extensive research on absorption, desorption studies remain limited. This study focuses on the desorption analysis through experimental runs in a pilot-scale tray column with varying flow rates, validating an Aspen Plus model. The research compares the impact of the number of stages, feed stage position, column pressure, and reflux ratio between equilibrium and rate-based models. The findings reveal enhanced desorption efficiency through optimized operational conditions, including reduced flow rates, additional equilibrium stages, feeding stage positioning closer to the condenser, elevated pressures, and lower reflux ratios. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

The extensive use of fossil energy leads to wanton emission of CO₂ and serious environmental problems. The exploration of high-performance catalysts plays a pivotal role in CO₂ resource utilization. In this paper, CuCe_yK catalysts are prepared by wet impregnation method using ordered mesoporous SiO₂ as support for the reverse water gas shift (RWGS) reaction. The physicochemical properties of the prepared catalysts are characterized by H₂-TPR, BET, XRD, Quasi in-situ XPS, H₂-TPD, and CO₂-TPD techniques. The results demonstrate thatthe Cu⁰ species can form synergistic effects with oxygen vacancies (O_v) to enhance the CuCe_yK catalytic performance. Additionally, the electronic effects between Ce and Cu not only enhances the adsorption and activation performances of the catalyst towards CO₂ and H₂ molecules, but also effectively suppresses the sintering of Cu⁰ species, thereby enhancing the stability of the corresponding catalyst. It is worth mentioning that the Ce content also directly affects the catalytic performances of the CuCe_yK catalyst. The CuCe₁₅K catalyst with a Ce content of 15% displays excellent CO₂ hydrogenation performances, and the CO₂ conversion and CO selectivity up to 41 % and 100 % at 420 °C, respectively. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

The CO₂-derived dimethyl carbonate (DMC) synthesis process becomes greatly attentive but suffers high energy consumption in DMC distillation process. In this work, the DMC-MeOH azeotropes separation process by pressure swing distillation and extractive distillation was compared, and key operating parameters, including the total number of trays and the feeding position of the mixture liquid, were optimized with the minimum total annual cost (TAC) as the objective function. On the basis of this optimization, economic evaluation of different distillation processes was conducted, and it was found that extractive distillation was more economical than pressure swing distillation. The application of the dividing-wall distillation process upgraded by extractive distillation can significantly reduce the minimum annual total cost by 37.4% and 10.7% compared to the original pressure swing distillation and extractive distillation process, respectively. The optimization of relevant heat exchange network based on pinch technology resulted in energy consumption reduction by 27.2% and 25.9% for its hot and cold utilities, respectively. Carbon life cycle assessment (LCA) on the DMC distillation process revealed over 50% of energy as well as carbon emissions from steam consumption, whose reduction can significantly minimize CO₂ emissions, energy consumption, and ultimate cost. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

Natural gas hydrate (NGH), is a new green-sustainable energy source, and the process of recovering CH₄ from NGH by replacing CO₂ is regarded as an advantageous way to mine NGH. However, improving the replacement efficiency of CO₂-CH₄ hydrate is a critical problem in the CO₂ replacement mining process. The feasibility study of the replacement for CO₂-CH₄ hydrate, as well as the research status of the replacement characteristics for various situations, is examined in this review. Additionally, the microscopic mechanism of CO₂-CH₄ hydrate replacement in porous media is explored in detail. The basic molecular dynamic (MD) simulation method and primary influencing factors of CO₂-CH₄ hydrate replacement were summarized systematically. Finally, the shortcomings of MD simulation of CO₂-CH₄ hydrate replacement process in porous medium system and the future development direction are pointed out. The relevant results will offer helpful direction for future NGH exploitation. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

The environmental and economic performance of a post-combustion solvent-based carbon capture system (CCS) combined with a selective catalytic reduction (SCR) system is investigated on a 48,600 kW engine container ship to meet the International Maritime Organization's emission reduction strategies through 2050. The proposed system uses aqueous ammonia to mitigate the produced CO₂ and NO_X emissions onboard a ship. Moreover, the combined system is investigated through a voyage-based case study using an engine room simulator, assuming that CCS and SCR are implemented on the reference ship. During the case study, the referenced container ship sailed from Rotterdam to New York, and the estimations were made by using Netpas Distance 4.0 software program. Results indicate that a total of 3,606.04 ton-CO₂ and 92.40 ton-NO_X are produced, while 3,345.43 ton-CO₂ and 40.67 ton-NO_X are captured during the voyage. Furthermore, an economic analysis is carried out after the case study. Findings of the economic analysis are: CAPEX of CCS is $32.07 MM and SCR is $2.19 MM, while OPEX of CCS and SCR are $188,873 and $103,681, respectively. In addition, it was calculated that implementing CCS could avoid the CO₂ tax cost of $19,472, while the economic value of the CO₂ captured was $113,590. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

The cover image is based on the Modeling and Analysis Mechanistic analysis of acid gas storage and oil recovery in naturally fractured reservoirs using single matrix block approach by Goran Shirzad et al., https://doi.org/10.1002/ghg.2276.

Pipelines stand as the most cost-effective method for large-scale transportation of CO₂ from a source point to the storage site, especially over extensive distances. The potential for crack propagation following a pipeline rupture highlights the need for precise analysis of decompression wave propagation. To accurately model this, understanding the decompression wave's propagation laws becomes imperative. Although previous studies have predominantly focused on pipeline leaks within the dense phase or supercritical state, the transition from liquid to gas during leakage significantly affects the decompression wave propagation. When a gaseous CO₂ pipeline ruptures, the high Joule-–Thomson coefficient causes a swift temperature plunge, potentially leading to a gas–liquid transition. However, research on how this phase transition impacts the decompression wave characteristics is limited. To address this gap, this study proposes a transition computational fluid dynamics model to predict the decompression wave behavior. The model is validated with an industrial-scale full-bore rupture experiment. The results reveal that the gaseous CO₂ leakage induces a pressure plateau at a certain distance from the leakage due to the gas-liquid phase transition. The influences of initial conditions on this pressure plateau and decompression wave are also explored. This study provides valuable insights into understanding the decompression wave behaviors of gaseous CO₂ pipelines, which are essential for ensuring the safety and reliability of CO₂ transportation within the carbon capture and storage technology chain. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

We reported new in-situ ternary nano/microcomposite layered double hydroxides/Ag₂O/bayerite in trimetallic NiAg/Al layered double hydroxides (LDH) via hydrothermal technique; and characterization by powder X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), and N₂ adsorption-desorption. The formation of bayerite and silver oxide species on the LDH nanosheet depended on the excess of Al³⁺ and Ag⁺ in the solution under alkaline and hydrothermal conditions. The nitrogen isotherm adsorption profile for all ternary composites exhibited uniformity with mesoporous and lamellar characteristics. The surface area of all the composites ranged from 81.17 to 150.23 m². g⁻¹, the Barret-Joyner-Halenda (BJH) pore volume from 0.22 to 0.27 cm³. g^−1, and the average pore diameter ranged from 3.47 to 5.78 nm. All composites show a laminar plate-like structure covered with elongated pieces. The particle size of the composites ranged from 54.86 to 115.96 nm, indicating the size changed from nano to microcomposite because of the different molar ratios of Ag and Ni in the solid. The ternary composite reveals CO₂ capture activity with adsorption capacity ranging from 13.93 to 19.61 mmol g⁻¹. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.

Hydrogen (H₂) fuel is assessed to be a major component of sustainable energy systems in the net-zero world. However, hydrogen storage is challenging and requires safe and environmentally friendly solutions like H₂ geo-sequestration. This study evaluates the effects of sulphate-reducing bacteria (SRB) on H₂ geological storage potential in the basalt rock. Fourier-transform infrared spectroscopy (FTIR) findings show the presence of significant components, that is, O-Si-O and organic functional groups, that is, aromatics, amine salts, alkane, and cyclohexane in the basalt rock immersed in the nutrient solution without SRB. However, we found that C-H stretching modes of organics with peaks at 1,465 cm⁻¹ were observed. Consequently, amine salt (N-H) (850–750 cm⁻¹), solvent impurities (C-H), and alkane spectrums are components of nutrient solutions and can be results of metabolic microbial activity that can influence on the surface of the basalt rock. Hence, these changes indicate the presence of microbial activity which might affect the surface chemistry of the rock leading to wettability alteration. We observed that the contact angle (θ) of brine-H₂ on the rock surface slightly changed from 500 to 4,000 psi pressure after the effect of bacteria at 50 °C. The wettability changed the surface of the rock from strong water-wet to weak or intermediate water-wet condition (i.e., θ < 75°) at 4,000 psi and temperatures 25 and 50 °C after the bacteria effect. The affiliation of brine water reduces on the rock surface with increasing temperatures and pressures, even without microbial influence. Additionally, we investigated interfacial tension and capillary pressure on SRB bacteria treated basalt which is not yet reported in the published work. Interfacial tension (IFT) and P_c of H₂ were reduced by 19% and 65%, respectively at 50 °C and 4,000 psi after the bacteria effect. Hence, the above findings could help to answer the key factors of the reservoir rock including wettability, capillary pressure, and interfacial tension to plan a field-scale H₂ geo-sequestration strategy under the influence of biotic life. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.