CO₂-removal News

Xiong et al. (2024): Seaweed farming environments do not always function as CO2 sink under synergistic influence of macroalgae and microorganisms

Tianqi Xiong, Hongmei Li, Yubin Hu, Wei-dong Zhai, Zhe Zhang, Yi Liu, Jihong Zhang, Longfei Lu, Lirong Chang, Liang Xue, Qinsheng Wei, Nianzhi Jiao, Yongyu Zhang IN: Agriculture, Ecosystems & Environment 361, 108824, https://doi.org/10.1016/j.agee.2023.108824

Through in-situ mesocosm cultivation experiments and eight field investigations covering different kelp growth stages in an intensive farming area in China, we found that compared with the surrounding seawater without kelps, the seawater at the fast-growth stage of kelp was a sink of CO2 (pCO2 decreased by 17−73 μatm), but became a source of CO2 at the aging stage of kelp (pCO2 increased by 20−37 μatm).

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Deutschlands radikaler Dreifach-Plan für die Weltklimakonferenz

focus.de, 26.11.2023, 22:16 Uhr

„Die anstehende Klimakonferenz – auch COP28 genannt – ist schon das 28. Treffen dieser Art. Was soll das Ganze also eigentlich noch? Zweifel sind berechtigt. Die Prozesse sind schwerfällig, die Vereinbarungen oft freiwillig. Und doch: Allein die Tatsache, dass sich Vertreter von rund 200 Staaten zusammenfinden, ist nicht selbstverständlich. Alle beteiligten Staaten, selbst China oder Russland, erkennen damit de facto an: Wir haben ein gemeinsames Problem. Ein Überblick, um welche vier Punkte es dabei geht – und was auf dem Spiel steht.“

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Lefvert & Grönkvist (2023): Lost in the scenarios of negative emissions: The role of bioenergy with carbon capture and storage (BECCS)

Adrian Lefvert, Stefan Grönkvist IN: Energy Policy, 113882, https://doi.org/10.1016/j.enpol.2023.113882

With this policy perspective article the authors question the ongoing discussion about the use of biomass for BECCS with basis in three points: (1) under the enhanced transparency framework under the Paris agreement, all parties to the agreement will use the same guidelines to estimate emissions by sources and removals by sinks, in which the emissions and removals in connection to cultivation of biomass are accounted for in the land-use, land-use change and forestry (LULUCF) sector, (2) adding carbon capture to existing processes may lead to a shift in products from that process rather than an increase in biomass use, and (3) BECCS requires substantial financial incentives.

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Wu et al. (2023): Facile synthesis of structured adsorbent with enhanced hydrophobicity and low energy consumption for CO2 capture from the air

Junye Wu, Yanlin Chen, Yifei Xu, Siyu Chen, Haotian Lv, Zhuozhen Gan, Xuancan Zhu, Ruzhu Wang, Chi-Hwa Wang, Tianshu Ge IN: Matter, https://doi.org/10.1016/j.matt.2023.10.019

Formulating materials into structured configurations is important to improve CO2 capture efficiency. Here, the hydrophobic polystyrene-block-polybutadiene-block-polystyrene (SBS) is used as the binder to coat polyethyleneimine (PEI) mesoporous cellular foam (MCF) onto ceramic fiber honeycombs. It not only makes the powder attach stably and uniformly on the honeycomb but also maintains the porosity for favorable CO2 diffusion. The synthesis was optimized, and a capacity of 0.71 mmol g−1 composite (or 2.33 mmol g−1 adsorbent) in 400 ppm CO2 is presented. The SBS endows the structured adsorbent with enhanced hydrothermal stability, as verified by the steam purge and accelerated stability experiments.

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Zolfaghari et al. (2023): Simulation of Carbon Dioxide Direct Air Capture Plant Using Potassium Hydroxide Aqueous Solution: Energy Optimization and CO2 Purity Enhancement

Zahra Zolfaghari, Alireza Aslani, Rahim Zahedi, Sina Kazzazi IN: Energy Conversion and Management, 100489, https://doi.org/10.1016/j.ecmx.2023.100489

The present study adopts the high-temperature DAC method with an aqueous KOH absorbent as its focus, aiming to mitigate energy consumption. Given that a substantial portion of energy consumption in comparable processes can be attributed to the calciner and slaker units, our research centers its attention on the Air Separation Unit (ASU) and the steam cycle unit, investigating their impact on the system’s production capacity, the enhancement of CO2 purity, and the augmentation of equipment thermal recovery. Process optimization, results a remarkable increase in heat recovery (21.1%) and significant reductions in utilities consumption.

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Book: Cost Analysis of Adsorption based Air Capture of CO2

Mona Muzammil, Muzammil Arshad, Muazzam Arshad; Edinburg: The University of Texas Rio Grande Valley. https://scholarworks.utrgv.edu/chem_fac/262.

The book opens with an introductory section that provides background regarding the need to reduce greenhouse gas emissions, an overview of carbon capture and storage (CCS) technologies, and a primer in the fundamentals of power generation. Chapters focus on key carbon capture technologies, including absorption, adsorption, and membrane-based systems, addressing their applications in both the power and non-power sectors.

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Nature – Gidden et al. (2023): Aligning climate scenarios to emissions inventories shifts global benchmarks

Matthew J. Gidden, Thomas Gasser, Giacomo Grassi, Nicklas Forsell, Iris Janssens, William F. Lamb, Jan Minx, Zebedee Nicholls, Jan Steinhauser,Keywan Riahi IN: Nature; https://doi.org/10.1038/s41586-023-06724-y

National greenhouse gas inventories (NGHGIs) and scientific assessments of anthropogenic emissions follow different accounting conventions for land-based carbon fluxes resulting in a large difference in the present emission estimates, a gap that will evolve over time. Using state-of-the-art methodologies and a land carbon-cycle emulator, the authors align the Intergovernmental Panel on Climate Change (IPCC)-assessed mitigation pathways with the NGHGIs to make a comparison.

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Stephenson & Allwood (2023): Technology to the rescue? Techno-scientific practices in the United Kingdom Net Zero Strategy and their role in locking in high energy decarbonisation pathways

Sam D. Stephenson, Julian M. Allwood IN: Energy Research & Social Science, 106, 103314, https://doi.org/10.1016/j.erss.2023.103314

This article reviews the characteristics of fifteen different UK Net Zero pathways (three government pathways and 12 additional pathways) and shows how the expectation of technology innovation and low-carbon energy abundance closes down the space potential pathways can occupy. In particular, the authors find that while conceptually different, the three government pathways display a high degree of similarity and that the majority of pathways rely on significant amounts of new clean energy and retain large residual emissions in 2050 which requires the deployment of significant new carbon dioxide removal technologies.

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