Hydrogen production from natural gas and biomethane with carbon capture and storage - A techno-environmental analysis

This study presents an integrated techno-environmental assessment of hydrogen production from natural gas and biomethane, combined with CO2 capture and storage (CCS). We have included steam methane reforming (SMR) and autothermal reforming (ATR) for syngas production. CO2 is captured from the syngas with a novel vacuum pressure swing adsorption (VPSA) process, that combines hydrogen purification and CO2 separation in one cycle. As comparison, we have included cases with conventional amine-based technology. We have extended standard attributional Life Cycle Assessment (LCA) following ISO standards with a detailed carbon balance of the biogas production process (via digestion) and its by-products. The results show that the life-cycle greenhouse gas (GHG) performance of the VPSA and amine-based CO2 capture technologies is very similar as a result of comparable energy consumption. The configuration with the highest plant-wide CO2 capture rate (almost 100% of produced CO2 captured) is autothermal reforming with a two-stage water-gas shift and VPSA CO2 capture – because the latter has an inherently high CO2 capture rate of 98% or more for the investigated syngas. Depending on the configuration, the addition of CCS to natural gas reforming-based hydrogen production reduces its life-cycle Global Warming Potential by 45–85 percent, while the other environmental life-cycle impacts slightly increase. This brings natural gas-based hydrogen on par with renewable electricity-based hydrogen regarding impacts on climate change. When biomethane is used instead of natural gas, our study shows potential for net negative greenhouse gas emissions, i.e. the net removal of CO2 over the life cycle of biowaste-based hydrogen production. In the special case where the biogas digestate is used as agricultural fertiliser, and where a substantial amount of the carbon in the digestate remains in the soil, the biowaste-based hydrogen reaches net-negative life cycle greenhouse gas emissions even without the application of CCS. Addition of CCS to biomethane-based hydrogen production leads to net-negative emissions in all investigated cases.ISSN:2398-490

Chapter 9 : CO2 Use

This report on carbon capture, use, and storage (CCUS) answers the Secretary of Energy's request for advice on the actions needed to deploy CCUS technologies at scale in the United States. The report concludes that at-scale deployment requires strong collaboration between industry and government; improved policies, financial incentives, and regulations; broad-based innovation and technology development; and increased understanding and confidence in CCUS–to create a roadmap for achieving at-scale deployment over the next 25 year

Comparative Environmental Life Cycle Assessment of Oxyfuel and Post-combustion Capture with MEA and AMP/PZ - Case Studies from the EDDiCCUT Project

This work presents the results of a comparative life cycle assessment study for three CCS technologies applied to a coal-fired power plant: post-combustion capture with MEA, post combustion capture with AMP/PZ and cryogenic oxy-fuel. This study has been performed in the context of the EDDiCCUT project, which aims to develop an environmental due diligence framework for assessing novel CCUS technologies. The research shows that there are no significant differences in climate change potential (CCP) for the technologies under study. In the three cases the reduction is about 70% (70% for the plant with MEA, 71% for the plant with AMP-PZ, and 73% for the plant with oxy-fuel technology). With regard to other impacts (e.g., acidification, toxicity, resource depletion) the results show an increase in the impacts as consequence of CCS, mostly driven by the increase amount of feedstock per kWh. Contrary to CCS, there are clear differences among the technologies with results ranging between 20 and 30%. Toxicity impacts related to the operation of the solvent-based carbon capture unit were also considered; however, it was observed that their contribution was only around 2% of the total impact for human toxicity potential. Rather, the largest contributor to human toxicity impacts in the life cycle of coal power plants with and without CCS is coal mining waste disposal

On the climate impacts of blue hydrogen production

Natural gas based hydrogen production with carbon capture and storage is referred to as blue hydrogen. If substantial amounts of CO2 from natural gas reforming are captured and permanently stored, such hydrogen could be a low-carbon energy carrier. However, recent research raises questions about the effective climate impacts of blue hydrogen from a life cycle perspective. Our analysis sheds light on the relevant issues and provides a balanced perspective on the impacts on climate change associated with blue hydrogen. We show that such impacts may indeed vary over large ranges and depend on only a few key parameters: the methane emission rate of the natural gas supply chain, the CO2 removal rate at the hydrogen production plant, and the global warming metric applied. State-of-the-art reforming with high CO2 capture rates combined with natural gas supply featuring low methane emissions does indeed allow for substantial reduction of greenhouse gas emissions compared to both conventional natural gas reforming and direct combustion of natural gas. Under such conditions, blue hydrogen is compatible with low-carbon economies and exhibits climate change impacts at the upper end of the range of those caused by hydrogen production from renewable-based electricity. However, neither current blue nor green hydrogen production pathways render fully “net-zero” hydrogen without additional CO2 removal

Specialty grand challenge: renaming our section to “Carbon Dioxide Removal”

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Best Practices and Recent Advances in Ccs Cost Engineering

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A structured approach for selecting carbon capture process models : A case study on monoethanolamine

Carbon capture and storage is considered a promising option to mitigate CO2 emissions. This has resulted in many R&D efforts focusing at developing viable carbon capture technologies. During carbon capture technology development, process modeling plays an important role. Selecting an appropriate process model for carbon capture technologies is not trivial, because of the large range of technology options, the difference in technology development stage, and the different purposes for which a process model can be used. This paper proposes a five-step, structured approach, designed to support the selection of carbon capture process models. The approach is illustrated with a post-combustion (monoethanolamine) case study. The paper shows intermediate and output results of the structured approach, and of the MEA case

Best Practices and Recent Advances in Ccs Cost Engineering

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Absorption based CO2 capture using KOH solution coupled with electrochemical regeneration cell: process model development

<p>This Conference abstract was presented during the TCCS12 conference in July of 2023, Trondheim, Norway. It shows two parts of a process model, used to model the ConsenCUS CO2 capture installation. </p&gt

Challenges and uncertainties of ex ante techno-economic analysis of low TRL CO2 capture technology: Lessons from a case study of an NGCC with exhaust gas recycle and electric swing adsorption

this work addresses the methodological challenges of undertaking techno-economic assessments of very early stage (technology readiness level 3-4) CO2 capture technologies. It draws lessons from a case study on CO2 capture from a natural gas combined cycle with exhaust gas recycle and electric swing adsorption technology. The paper shows that also for very early stage technologies it is possible to conduct techno-economic studies that give a sound first indication of feasibility, providing certain conditions are met. These conditions include the availability of initial estimates for the energy use of the capture technology, either from bench scale measurements, or from rigorous process models, and the possibility to draw up a generic (high level) equipment list. The paper shows that for meaningful comparison with incumbent technologies, the performance of very early stage technologies needs to be projected to a future, commercial state. To this end, the state of the art methods have to be adapted to control for the development and improvements that these technologies will undergo during the R & D cycle. We call this a hybrid approach. The paper also shows that CO2 capture technologies always need to be assessed in sympathy with the CO2 source (e.g. power plant) and compression plant, because otherwise unreliable conclusions could be drawn on their feasibility. For the case study, it is concluded that electric swing adsorption is unlikely to become economically competitive with current technologies, even in a highly optimised future state, where 50% of the regeneration duty is provided by LP steam and 50% by electricity: the net efficiency of an NGCC with EGR and optimised ESA (49.3%(LHV); min-max 45.8-50.4%(LHV) is lower than that of an NGCC with EGR and standard MEA (50.4%(LHV)). Also, investment and operational costs are higher than MEA, which together with ESA's lower efficiency leads to an unfavourable levelised cost of electricity: 103 (sic)/MWh (min-max 93.89-117.31 (sic)/MWh) for NGCC with ESA, versus 91 (sic)/MWh for NGCC with MEA