Capture Options Research Articles

Advancing Low-CO2 Sorption Technology: Density Adjustment of Urea-Resistant Secondary Monoamine for Improved Adsorption Performance

Amine-containing adsorbents, recognized for their lower desorption energy in comparison to aqueous amine, have encountered challenges stemming from poor stability and inadequate working capacity under realistic operational conditions, impeding their adoption as viable CO2 capture options. The alteration of amine groups using epoxy-based agents has been demonstrated to effectively inhibit undesirable urea formation, but decreases amine density and thereby the CO2 adsorption capacity. Although secondary monoamine structures have been found to possess anti-urea stability, their CO2 uptake has never been optimized. Consequently, we systematically adjusted the density of N-methylaminopropyltrimethoxysilane on pore-expanded MCM-41 by optimizing the water and aminosilane levels for grafting. Additionally, an expression was developed to estimate the location of aminosilane on the mesoporous silica. The adsorbent with the highest amount of aminosilane grafted inside the pores showed the best capacity (1.94 mmol/g under 40 °C and 5 v% CO2), and an adsorption efficiency close to the theoretical maximum (i.e., 0.5, dry feed). The adsorbent also demonstrated rapid adsorption (1.76 mmol/g in 3 min) and no loss during long-term stability tests (366 and 423 h) performed under industrially relevant conditions.

Evaluation of the Mineral Manganese OXMN009 and OXMN009P in the Chemical Looping Combustion (CLC) Process Using Thermogravimetry

Indirect combustion with the chemical looping combustion (CLC) of solid oxygen carriers is one of the most promising technologies for capturing carbon dioxide (CO2) in energy production from fossil fuels since the separation of the generated CO2 is inherent to the process itself. Therefore, the cost associated with capturing this gas will be significantly reduced. This technology transfers oxygen from air to fuel through a metal oxide that acts as an oxygen carrier, avoiding direct contact between air and fuel. This oxygen carrier circulates in a fluidized bed reactor called a reduction reactor and an oxidation reactor. (1) This research work has focused on evaluating the behavior of oxygen carriers based on the original and improved manganese mineral (copper-impregnated mineral) named for this study, OXMN009 and OXMN009P, respectively. (2) Equilibrium experiments were carried out on a thermogravimetric balance (TGA) to evaluate the kinetic behavior of these oxygen transporters OXMN009 and OXMN009P, using the gases methane (CH4), carbon monoxide (CO), and hydrogen (H2). (3) The enhanced solid oxygen carrier OXMN009P exhibited good performance for the CLC process with gaseous fuels in terms of reactivity and combustion efficiency, having high reactivity and oxygen transfer properties due to copper impregnation. (4) The results show that OXMN009P has comparable reactivity to other manganese-based materials reported in the literature. It may be an effective option for carbon dioxide capture, as it uses metal oxides as the oxygen transporters (TO). (5) These oxygen transporters, OXMN009 and OXMN009P, are used in a cyclic process that prevents the formation of nitrogen oxides by keeping the air and fuel separate. (6) Thermogravimetric balance (TGA) experiments were conducted to evaluate the kinetic behavior of these copper-modified oxygen transporters. (7) It was found that OXMN009P improved the reactivity and oxygen transfer properties due to copper impregnation. The kinetic parameters obtained in the TGA indicate that the reaction is non-thermal and requires less energy to initiate. (8) The results show that OXMN009P has reactivity comparable to other manganese-based materials reported in the literature and can be an effective option for carbon dioxide capture.

Geospatial techno-economic and environmental assessment of different energy options for solid sorbent direct air capture

Geospatial techno-economic and environmental assessment of different energy options for solid sorbent direct air capture

Circular Economy Integration in 1G+2G Sugarcane Bioethanol Production: Application of Carbon Capture, Utilization and Storage, Closed-Loop Systems, and Waste Valorization for Sustainability

Bioethanol production is a vital player in the renewable energy landscape. However, it faces pressing issues regarding carbon emissions and resource management. Traditional open-loop systems generate substantial waste and pollution, exacerbating environmental concerns. Various emerging technologies offer promising solutions. Carbon Capture, Utilization, and Storage (CCUS) presents avenues for tackling carbon emissions. Utilization transforms CO2 emissions into valuable products, while Storage securely stores emissions to prevent atmospheric release. Closed-loop processes and waste valorization capitalize on material reuse, conserving natural resources, and minimizing waste. By promoting resource efficiency and waste minimization, circular economy principles align seamlessly with CCUS, closed-loop systems, and waste valorization. This study delves into utilizing Utilization technologies tailored to sugarcane 1G+2G bioethanol production, evaluates CO2 capture options, and presents applications. Storage strategies suitable for bioethanol production facilities are scrutinized, and deployment options are explored, highlighting the closed-loop system and waste valorization's role in waste reduction and environmental preservation. Through synergistic integration, these technologies pave the way for sustainable sugarcane bioethanol production, addressing economic and technological challenges while fostering innovation and collaboration. This comprehensive study will serve as a guide for transitioning to a circular economy model in bioethanol production.

Computational study of Capturing CO2 and SO2 gases using imidazolium based ionic liquids

The objective of this study was to capture toxic gases like CO2 and SO2 using imidazolium based ionic liquids,1-butyl 3-methyl-imidazoliumbis(trifluoromethylsulfonyl)imide) and 1-ethyl 3-methyl-imidazolium acetate. In this work, the density functional theory (DFT) method of hybrid correlation functional with B3LYP/6-31++G (d, p) basis set was used to analyze the mechanism of interaction between toxic gases and ionic liquids. It has been founded that the [Bmim][Tf2N]-SO2 has greater binding energy than [Bmim][Tf2N]-CO2 . Therefore, the ionic liquid [Bmim][Tf2N] seems to be the most suitable option for SO2 gas capture. Similarly, The ionic liquid [Emim][Ac] has high efficiency to capture the toxic gas SO2 and has high affinity for this gas relative to CO2. The types of absorption observed in [Bmim][Tf2N]-SO2 interaction was Chemisorption while, [Bmim]Tf2N]-CO2 interaction was physisorption. To sum up, [Bmim][Tf2N] and [Emim][Ac] seems to be the most suitable option and has high efficiency to capture SO2 gas relative to CO2. Bangladesh J. Sci. Ind. Res. 59(2), 73-86, 2024

Determination of the optimal total oxygen concentration and oxygen partitioning ratio based on the heat transfer characteristics of oxy-coal combustion in a swirl burner

Oxy-coal combustion is an attractive option for CO2 capture from coal-fired power plants due to high carbon capture efficiency and favorable economic performance. It is critical for the operation of the power plants to maintain similar heat transfer characteristics by rationalizing the partitioning strategy of the oxidant streams when retrofitting coal-fired power plants with oxy-fuel combustion technology. In the present work, the oxy-coal combustion characteristics under various total oxygen concentrations XO2,total of 21 %–32 % and oxygen partitioning ratio conditions in a 100 kW vertical swirl burner were numerically investigated by using computational fluid dynamics (CFD) models. And the effects of the XO2,total and oxygen partitioning ratio on the heat transfer characteristics of oxy-coal combustion were numerically simulated to quantitatively obtain the optimal oxygen supply partitioning strategy for the retrofitting of coal-fired power plants. Then the flame structure, heat transfer flux, and char burnout rate at different oxygen partitioning ratios between the primary and secondary streams were systematically analyzed to further determine the optimal oxygen partitioning ratio. The results showed that the maximum flue gas temperature Tmax increased by 220 K and the total heat transfer flux on the furnace wall increased by 42 % when the XO2,total was increased from 21 % to 32 %, respectively. Under oxy-coal combustion conditions, the Tmax at the XO2,total of 32.4 % was consistent with that under air combustion condition, while the total heat transfer flux at the XO2,total of 29.4 % matched with that under air combustion condition. Moreover, the total heat transfer flux and the flame length were increased by 17.3 % and 46.3 %, respectively, as the oxygen concentration of the primary stream XO2,Pri was increased from 6.5 % to 45 % at the XO2,total of 29 %. More importantly, the total heat transfer flux at the XO2,Pri of 31.9 % under oxy-coal combustion condition matched with that under air combustion condition. The optimal total oxygen concentration and oxygen partitioning ratio of oxy-coal combustion based on the heat transfer characteristics were quantitatively determined, which gave an important reference for the oxy-coal combustion retrofitting of traditional coal-fired power plants.

ProteusNeRF: Fast Lightweight NeRF Editing using 3D-Aware Image Context

Neural Radiance Fields (NeRFs) have recently emerged as a popular option for photo-realistic object capture due to their ability to faithfully capture high-fidelity volumetric content even from handheld video input. Although much research has been devoted to efficient optimization leading to real-time training and rendering, options for interactive editing NeRFs remain limited. We present a very simple but effective neural network architecture that is fast and efficient while maintaining a low memory footprint. This architecture can be incrementally guided through user-friendly image-based edits. Our representation allows straightforward object selection via semantic feature distillation at the training stage. More importantly, we propose a local 3D-aware image context to facilitate view-consistent image editing that can then be distilled into fine-tuned NeRFs, via geometric and appearance adjustments. We evaluate our setup on a variety of examples to demonstrate appearance and geometric edits and report 10-30x speedup over concurrent work focusing on text-guided NeRF editing. Video results and code can be found on our project webpage at https://proteusnerf.github.io.

A Comprehensive Assessment of Carbon Dioxide Removal Options for Germany

AbstractTo reach their net‐zero targets, countries will have to compensate hard‐to‐abate CO2 emissions through carbon dioxide removal (CDR). Yet, current assessments rarely include socio‐cultural or institutional aspects or fail to contextualize CDR options for implementation. Here we present a context‐specific feasibility assessment of CDR options for the example of Germany. We assess 14 CDR options, including three chemical carbon capture options, six options for bioenergy combined with carbon capture and storage (BECCS), and five options that aim to increase ecosystem carbon uptake. The assessment addresses technological, economic, environmental, institutional, social‐cultural and systemic considerations using a traffic‐light system to evaluate implementation opportunities and hurdles. We find that in Germany CDR options like cover crops or seagrass restoration currently face comparably low implementation hurdles in terms of technological, economic, or environmental feasibility and low institutional or social opposition but show comparably small CO2 removal potentials. In contrast, some BECCS options that show high CDR potentials face significant techno‐economic, societal and institutional hurdles when it comes to the geological storage of CO2. While a combination of CDR options is likely required to meet the net‐zero target in Germany, the current climate protection law includes a limited set of options. Our analysis aims to provide comprehensive information on CDR hurdles and possibilities for Germany for use in further research on CDR options, climate, and energy scenario development, as well as an effective decision support basis for various actors.

Thermal‐Conductive MOFs@BN Self‐Supporting Foams for Synchronously Boosting CO2 Adsorption/Desorption

AbstractSynchronous boosting adsorption and desorption efficiency is a great challenge for CO2 adsorption capture, especially for metal–organic frameworks (MOFs) having high adsorption uptakes. Herein, a novel “self‐supporting foam” strategy is proposed to fabricate a thermally conductive MOFs@boron nitride nanosheets (BNNS) composite foam (MOFs@BNNS‐PEI) via polyethyleneimine (PEI) cross‐linkage. The “rebar” BNNS and the “aggregate” MOFs are packed against each other to form a self‐supporting structure, effectively reducing the reliance on polymers to maintain high MOFs loading. Furthermore, this approach enables the successful fabrication of three different types of typical MOFs, including HKUST‐1, MIL‐100(Fe), and ZIF‐8. This unique design maintains a high specific surface area (SSA) of the MOFs foam and generates nitrogen‐rich microporosity contributing to CO2 adsorption. Additionally, PEI serves as a thermal bridge to reduce the interfacial thermal resistance between BNNS and MOFs, accelerating the thermal desorption of CO2 within the MOFs foam. Benefiting from these advantages, the MOFs@BNNS‐PEI exhibits a higher CO2 adsorption capacity (1.35–1.42 times that of pure MOFs) and a significant increase in the desorption rate for CO2 (5.0–5.7 times that of pure MOFs). Thus, the thermally conductive MOFs foam can be a viable option for efficient CO2 capture in practical applications.

Technology Focus: Completions (April 2024)

To start a text for high-level readers with a cliché is always a risk, but I will take it: “Data is the new oil.” When British mathematician Clive Humby coined this clever sentence in 2006, the thought-provoking idea behind it was that both oil and data need to be refined and processed to have value. Time and repetition eventually shaped the new, more common-sense meaning that data is as valuable as oil. And when the data refers to oil exploration and production, Humby’s statement becomes resounding, especially in its original meaning. The oil and gas industry, notably the completion activity, with its distributed sensors, optical fibers, permanent downhole gauges, sealed-wellbore pressure monitoring (SWPM), and microseismic, has generated a fantastic amount of data, which has increasingly been properly refined and processed, producing more information—and more oil. A quick search of OnePetro shows the number of papers that deal with the use of artificial intelligence with massive amounts of data that are being made available in the cloud to solve everything from the most prosaic completion decisions to the automatic design of stimulations in naturally fractured reservoirs. A good example of the use of data is shown in paper SPE 212922, which provides an in-depth analysis of interventions in the UK sector of the North Sea. Most of the conclusions, although mostly based on the UK Stewardship Survey, can be easily extrapolated to other regions of the world. And one of them puts its finger on the wound: the fear of asset managers of conducting interventions, even though they appear to be highly effective and economically viable. Paper SPE 212367 discusses the automation of SWPM data analysis for automatic volume-to-first-response matching, a great evolution in the design of refractures in the legendary Eagle Ford shales. And, if the evolution of completing unconventionals led the US to its historic production record in 2023, with more than 16 million BOE/D, in Argentina, shale gas has been a driver of development. The evolution of completions in the most famous unconventional prospect, Vaca Muerta, can be followed in paper SPE 212574. All of these great readings prove the cliché that “data is the new oil.” To complement the reading, a paper that will bring a discreet smile to a generation that breathlessly watched spaceships and even planets being destroyed by lasers, paper SPE 215016, details the industrial use of lasers in perforation. The future has finally arrived. To close the selections, two papers present current and important topics: completion options for carbon capture, use, and storage (SPE 216187) and innovations in autonomous inflow control devices, with the ingenious activation of the apparatus with chemical devices (SPE 216041). Recommended additional reading at OnePetro: www.onepetro.org. SPE 215016 First Industrial High-Power Laser Perforation Deployment by Sameeh I. Batarseh, Saudi Aramco, et al. SPE 216187 Improving Injection Efficiency in CCUS Wells: A Comparative Analysis of Different Completion Designs by Prakasa Bona, Halliburton, et al. SPE 216041Configurable Adaptive Chemical Inflow Control Device Eliminates Intervention by P. Asthana, Saudi Aramco, et al.

Promotion of CO2 fracturing for CCUS—the technical gap between theory and practice

CO2, used as an environmentally friendly fracturing fluid, has encountered a bottleneck in development in recent years. Despite great efforts in research work, limited progress has been made in field applications. In this study, an extensive literature review of research work and field cases was performed to summarize the technical issues and challenges of CO2 fracturing. The key issues of CO2 fracturing were analyzed to reveal the gap between fundamental research and field operations. The effects of CO2 properties on fracture creation and proppant transport were synthetically analyzed to extract new common research orientations, with the aim of improving the efficiency of CO2 injection. The hydraulic parameters of CO2 fracturing were compared with those of water-based fracturing fluids, which revealed a theory-practice gap. By studying the developing trends and successful experiences of conventional fluids, new strategies for CO2 fracturing were proposed. We identified that the major theory-practice gap in CO2 fracturing exists in pump rate and operation scale. Consequently, the friction reducer, effects of flow loss (due to leak-off) and distribution (within fracture networks), and shear viscosity of thickened CO2 are key factors in improving both fracture propagation and proppant transport. By increasing the scale of injected CO2, the CO2 fracturing technique can be enhanced, making it an essential option for carbon capture, utilization, and storage (CCUS) to reduce carbon emissions and mitigate climate change.

Aspects using of CO2 captured from stationary sources

The results of carbon dioxide (CO2), which is emitted into the atmosphere and creates a greenhouse effect as a result of the burning of natural methane gas (CH4) as a fuel in a number of large industrial enterprises in Azerbaijan, and the ways of its capture and efficient use from an economic point of view have been studied. Including, in the production of methanol and urea sulfur, increasing the oil yield of the layer by injecting it into the oil layers, increasing the productivity of plants, producing caustic soda, dry ice, carbonated water, etc. the effectiveness of its use in the fields has been investigated and proposals for scientific and technical solutions have been developed. This is both a decrease in the amount of CO2 gas in the atmosphere, which causes global climate changes, and also a saving of natural methane gas used in the production process. Options for carbon dioxide capture and storage and transportation to the destination have also been developed in the current research work.

Evaluating end-to-end continuous antibody manufacture with column-free capture alternatives from economic, environmental, and robustness perspectives.

Process intensification efforts have renewed interest in the potential of end-to-end continuous manufacture with column-free capture alternatives. This article describes a decisional tool that encompasses mass balance and design equations, process economics, stochastic simulation and multi-criteria decision-making and enables the evaluation of different batch, and continuous flowsheets for monoclonal antibody (mAb) manufacture. The traditional batch process was compared with end-to-end continuous bioprocesses with either protein A capture or column-free capture employing aqueous two-phase extraction or precipitation from economic, environmental, and robustness perspectives. The cost of goods analysis predicted that continuous flowsheets could offer substantial cost savings (~20%-40%) over the batch process at low and medium annual commercial demands (100-500 kg); however, at tonnage demands they resulted in either comparable or higher costs. Comparing the continuous options, the continuous flowsheets with protein A or precipitation yielded similar COG/g values, while aqueous two-phase extraction presented higher costs. The analysis of overall process mass intensities accounting for water and consumables suggested that the continuous flowsheet with protein A would result in the lowest environmental burden. When the economic, environmental, and operational criteria were reconciled using multi-criteria decision-making analysis, the continuous protein A-based flowsheet was found to be the most favorable. A target analysis highlighted the need for process improvements in the following parameters to reduce the manufacturing costs of the continuous column-free capture options below that of protein A: the perfusion volumetric productivity, the harvested cell culture fluid percentage in column-free operations, the column-free step yields along with the implementation of buffer concentrates.

Insight into the effect of pressure on the CO2 capture capacity and kinetics by a biochar-ionic liquid composite

Agave bagasse fibers-derived biochar (BCw) impregnated with 1-butyl-3-methylimidazolium acetate ionic liquid (IL) exhibited a considerably CO2 capture capacity at atmospheric (1.47 mmol/g at 25 °C and 1 bar) and moderately high pressure (1.32 mmol/g at 25 °C and 8.5 bar) under dynamic and static systems, respectively. Biochar-IL composites improved the CO2 capture capacity, kinetics, and selectivity (CO2/N2) by 4–90% compared with than of the bulk adsorbents. By increasing the working manometric pressure from 1 to 8.5 bar in a static high-pressure system, the CO2 capture capacity and kinetics of impregnated-biochar improved 2 times. Additionally, the biochar-IL composites were regenerated under a pressure swing adsorption (PSA) arrangement, where more than 70% of the desorption was attributed to the depressurization of the system. The proposed CO2 sorption mechanism suggests gas-solid physisorption and gas-liquid chemisorption at low pressure. At moderately high pressure (≥ 1 bar), the textural properties of the adsorbent play an important role. Moreover, this study provided evidence that the CO2 capture is not only related to the textural properties of the biochar, but also to its surface chemistry. The biochar-IL composite materials reported herein could be an option for CO2 capture at low and moderate pressures, which could reduce operating costs if implemented at large scale for CO2 separation from flue gases under a PSA design.

A low energy-consuming phase change absorbent of MAE/DGM/H2O for CO2 capture

The concept of phase change absorbents has been widely studied as a novel and low-energy consumption option for CO2 capture. This work screened diethylene glycol dimethyl ether (DGM) from 17 physical solvent species as a better phase change accelerator for absorbents of 2-(methylamino)ethanol (MAE)-physical solvent-H2O. Then, the optimized mass ratio of 30:49:21 for MAE-DGM-H2O solution was investigated with phase change behaviors, CO2 absorption–desorption performance, cyclic capacity, and energy consumption. The experimental results showed that the cyclic CO2 capacity reached 1.32 mol/L and the CO2-rich phase made up only 50.4 % of the total volume for the 30 wt%MAE-49 wt%DGM-21 wt%H2O, as well as its regenerative energy consumption was 40 % lower than that of 30 wt% monoethanolamine (MEA) solution. Also, the viscosity and surface tension gap of the CO2-rich phase and CO2-lean phase for the optimized absorbent were studied. It was observed that those gaps increase with the increasing mass ratio of DGM. In addition, the possible phase change mechanism was proposed by using the dipole moment values of components calculated by Gaussian (B3LYP/6-31G) coupled with 13C NMR spectra.

Comparison of membrane-based pre-and post-combustion co2 capture options applied in energy-intensive industrial applications

Comparison of membrane-based pre-and post-combustion co2 capture options applied in energy-intensive industrial applications

Carbon offset potential of biochar based straw management under rice- wheat system along Indo-Gangetic Plains of India

The Paris Agreement goal of a net-zero equation will require decarbonization technologies in agriculture. Agri-waste biochar offers huge potential for carbon abatement in agricultural soils. The present experiment was carried out to compare the effects of residue management, viz., no residue (NR), residue incorporation (RI), and biochar (BC), as well as nitrogen options for emission reduction and carbon capture under the rice-wheat cropping sequence (RWCS) of the Indo-Gangetic Plains (IGP), India. After two cycles of cropping pattern, the analysis revealed that the biochar application (BC) reduces the RWCS's annual CO2 emissions by 18.1 % over residue incorporation (RI), while CH4 and N2O emissions were reduced by 23 % and 20.6 % over RI and 11 % and 29.3 % over no residue (NR), respectively. The application of biochar-based nutrient composites with rice straw biourea (RSBU) at 100 % and 75 % significantly reduced greenhouse gases (CH4 and N2O) compared to commercial urea at 100 %. The global warming potential of cropping systems recorded with BC was 7 % and 19.3 % lower than NR and RI, respectively, while 6–15 % under RSBU over urea 100 %. The annual carbon footprint (CF) under BC and NR decreased by 37.2 % and 30.8 % over RI, respectively. The net CF under residue burning was estimated to be the highest (132.5 Tg CO2-Ce), followed by RI (55.3 Tg CO2-Ce), showing net positive emissions; however, net negative emissions were found under a biochar-based system. The estimated annual carbon offset potential of a complete biochar system over residue burning, incorporation, and partial biochar as calculated was 189, 112, and 92 Tg CO2-Ce yr−1, respectively. A biochar-based approach to managing rice straw had great carbon offset potential through a large drop in greenhouse gas emissions and an improved soil carbon pool under the rice wheat system along the IGP, India.

Temperature-vacuum swing adsorption for direct air capture by using low-grade heat

Direct air capture (DAC) is a promising carbon mitigation technology and will likely be part of extensive carbon removal portfolio. Adsorptive DAC is an appropriate option for carbon capture to utilize low-grade heat because of its desirable regeneration temperature and adaptability to be integrated with renewables. Building indoor environment with CO2 concentrations above 1000 ppm provides another suitable scenario for DAC. Herein, DAC using temperature-vacuum swing adsorption (TVSA) is presented and analyzed by integrating various low-grade heat sources in buildings. An amine-functionalized metal organic framework is selected for process simulation, and the performance is compared with those using other sorbents. It indicates that amine-functionalized material has advantages in CO2 productivity and purity. A techno-economic analysis is carried out to explore the benefit of the proposed DAC in buildings. The results show that regeneration by heat pumps at 373 K is the most competitive solution and has 176.7 $·tCO2−1 of the levelized cost of DAC (LCOD). Compared with conventional energy supply, solutions with low-grade heat utilization in buildings could achieve lower carbon intensity and increase by 5.2–25.0% in net LCOD. These results will provide practical guidelines for DAC application with lower energy penalties and costs.

Capacity of Sun-driven lunar swingby sequences and their application in asteroid retrieval

For deep-space mission design, the gravity of the Sun and the Moon can be first considered and utilized. Their gravity can provide the energy change for launching spacecraft and retrieving spacecraft as well as asteroids. Regarding an asteroid retrieval mission, it can lead to the mitigation of asteroid hazards and an easy exploration and exploitation of the asteroid. This paper discusses the application of the Sun-driven lunar swingby sequence for asteroid missions. Characterizing the capacity of this technique is not only interesting in terms of dynamic insights but also non-trivial for trajectory design. The capacity of a Sun-driven lunar swingby sequence is elucidated in this paper with the help of the "Swingby-Jacobi" graph. The capacity can be represented by a range of the Jacobi integral that encloses around 660 asteroids currently cataloged. To facilitate trajectory design, a database of Sun-perturbed Moon-to-Moon transfers, including multi-revolution cases is generated and employed. Massive trajectory options for spacecraft launch and asteroid capture can then be explored and optimized. Finally, a number of asteroid flyby, rendezvous, sample-return, and retrieval mission options enabled by the proposed technique are obtained.

Energetic and economic analysis of absorption-based CO2 capture integrated hydrogen production processes – Retrofit perspective

Efforts made to integrate absorption-based CO2 capture technologies with the production of hydrogen have mostly focused on new-build cases. Our understanding on the most appropriate way of implementing CO2 capture for blue hydrogen processes and its economic impact under retrofit scenarios are rather limited. In this study, the capture-integrated hydrogen plant is modeled and simulated using Aspen Plus, with which technical feasibility is evaluated with three potential positions of CO2 capture for PSA inlet gas, PSA tail gas and reformer flue gas streams. Three retrofit strategies for CO2 capture are established, of which techno-economic impact on the design of utility systems and its site-wide management is systematically investigated. TEA (techno-economic analysis) is carried out to determine the Levelized cost of hydrogen (LCOH), CO2 capture cost, and CO2 avoidance cost for three retrofit strategies subject to three capture options. From the case study presented, CO2 capture and avoidance cost is strongly dependent on the selection of CO2 capture option and retrofitting design philosophy, and CO2 capture for PSA inlet gas with fully utilizing excess energy from hydrogen plant is the most cost-effective strategy.