Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.C...Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.展开更多
Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising...Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas.展开更多
This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditi...This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.展开更多
This study investigates carbon dioxide(CO₂)sequestration and biomass distribution across various plant components and land use types in Ban Krang Subdistrict,Mueang District,Phitsanulok Province,with the goal of enhan...This study investigates carbon dioxide(CO₂)sequestration and biomass distribution across various plant components and land use types in Ban Krang Subdistrict,Mueang District,Phitsanulok Province,with the goal of enhancing carbon management strategies.Field surveys were conducted using 14 plots of 40×40 meters to quantify biomass and estimate CO₂sequestration across different vegetation types.The findings reveal an average CO₂sequestration of 122.81 ton ha⁻¹,with aboveground biomass,particularly stems,contributing the most to carbon storage.Notably,abandoned perennial crops and mixed perennial crops demonstrated the highest sequestration rates,at 657.94 ton ha⁻¹and 613.00 ton ha⁻¹,respectively.In contrast,agricultural lands such as rice paddies and cassava plantations exhibited the lowest sequestration rates,though rice paddies contributed the highest total CO₂sequestration,amounting to 61,119.71 tons,due to their extensive area.The study highlights the critical role of diverse and dense vegetation,particularly perennial crops,in maximizing carbon sequestration.It also underscores the potential for improving carbon storage in agricultural lands through better land management practices.The results suggest that targeted strategies should prioritize high-sequestration land use types while also enhancing carbon storage in low-sequestration areas.By optimizing land use and management practices,the region can significantly increase its carbon storage capacity,contributing to climate change mitigation and promoting long-term ecological sustainability.These insights are crucial for formulating effective carbon management strategies in Ban Krang Subdistrict,as well as in other comparable regions.展开更多
Growing concerns about greenhouse gas emissions from underground mining have intensified the need for carbon reduction strategies at every stage.Shotcrete used in tunnel support presents a promising opportunity for ca...Growing concerns about greenhouse gas emissions from underground mining have intensified the need for carbon reduction strategies at every stage.Shotcrete used in tunnel support presents a promising opportunity for carbon emission reduction.This study investigates the carbon absorption capacity,mechanical strength,and underlying mechanisms of shotcrete when exposed to varying CO_(2)concentrations during the mine support process.Findings reveal that higher CO_(2)concentrations during the initial stages of carbonation curing enhance early strength but may impede long-term strength development.Shotcrete samples exposed to 2vol%CO_(2)for 14 d exhibited a carbonation degree approximately three times higher than those exposed to 0.03vol%CO_(2).A carbonation layer formed in the shotcrete,sequestering CO_(2)as solid carbonates.In practical terms,shotcrete in an underground return-air tunnel absorbed 1.1 kg·m^(2)of CO_(2)over 14 d,equivalent to treating 33 m^(3)of contaminated air.Thus,using shotcrete for CO_(2)curing in return-air tunnels can significantly reduce carbon emissions,contributing to greener and more sustainable mining practices.展开更多
Geological sequestration of CO_(2)is critical for deep decarbonization,but the geomechanical stability of coal reservoirs remains a major challenge.This study integrates nanoindentation,XRD/SEM-EDS chemo physical char...Geological sequestration of CO_(2)is critical for deep decarbonization,but the geomechanical stability of coal reservoirs remains a major challenge.This study integrates nanoindentation,XRD/SEM-EDS chemo physical characterization and 4D CT visualization to investigate the time-evolving mechanical degradation of bituminous coals with ScCO_(2)injection.The main results show that 4 d of ScCO_(2)treatment caused 50.47%–80.99%increase in load–displacement deformation and 26.92%–76.17%increase in creep depth at peak load,accompanied by 55.01%–63.38%loss in elastic modulus and 52.83%–74.81%reduction in hardness.The degradation exhibited biphasic kinetics,characterized by rapid surface-driven weakening(0–2 d),followed by stabilized matrix-scale pore homogenization(2–4 d).ScCO_(2)preferentially dissolved carbonate minerals(dolomite),driving pore network expansion and interfacial debonding,while silicate minerals resisted dissolution but promoted structural homogenization.These coupled geochemical-mechanical processes reduced the mechanical heterogeneity of the coal and altered its failure modes.The results establish a predictive framework for reservoir stability assessment and provide actionable insights for optimizing CO_(2)enhanced coalbed methane recovery.展开更多
Mitigating climate change demands innovative solutions,and carbon sequestration technologies are at the forefront.Among these,basalt,a mafic volcanic rock packed with calcium,magnesium,and iron,emerges as a powerful c...Mitigating climate change demands innovative solutions,and carbon sequestration technologies are at the forefront.Among these,basalt,a mafic volcanic rock packed with calcium,magnesium,and iron,emerges as a powerful candidate for carbon dioxide(CO_(2))sequestration through mineral carbonation.This method transforms CO_(2)into stable carbonate minerals,ensuring a permanent and environmentally safe storage solution.While extensive research has explored into basalt’s potential under high hydration conditions,the untapped promise of low water content scenarios remains largely unexplored.Our ground-breaking study investigates the mineral carbonation of basalt powder under low water condi-tions using supercritical CO_(2)(sc-CO_(2)).Conducted at 50℃ and 15 MPa with a controlled moisture content of 30%,our experiment spans various time points(0,7,14,21,and 28 days).Utilising advanced X-ray diffraction(XRD)and scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS),we unveil the mineralogical and morphological transformations.The results are striking:even under low water conditions,basalt efficiently forms valuable carbonate minerals such as calcite,siderite,magnesite,and ankerite.The carbonation efficiency evolves over time,reflecting the dynamic transfor-mation of the basalt matrix.These findings offer pivotal insights into optimising CO_(2)sequestration in basalt under low hydration,marking a significant leap toward sustainable carbon capture and storage.展开更多
As the main factor influencing the flow and preservation of underground fluids,wettability has a profound impact on CO_(2)sequestration(CS).However,the influencing factors and internal interaction mechanisms of shale ...As the main factor influencing the flow and preservation of underground fluids,wettability has a profound impact on CO_(2)sequestration(CS).However,the influencing factors and internal interaction mechanisms of shale kerogen wettability remain unclear.In this study,we used molecular dynamics to simulate the influence of temperature,pressure,and salinity on wettability.Furthermore,the results were validated through various methods such as mean square displacement,interaction energy,electrostatic potential energy,hydrogen bonding,van der Waals forces,and electrostatic forces,thereby confirming the reliability of our findings.As temperature increases,water wettability on the surface of kerogen increases.At CO_(2)pressures of 10 and 20 MPa,as the temperature increases,the kerogen wettability changes from CO_(2)wetting to neutral wetting.As the CO_(2)pressure increases,the water wettability on the surface of kerogen weakens.When the pressure is below 7.375 MPa and the temperature is 298 or 313 K,kerogen undergoes a wettability reversal from neutral wetting to CO_(2)wetting.As salinity increases,water wettability weakens.Divalent cations(Mg2+and Ca2+)have a greater impact on wettability than monovalent cations(Na^(+)).Water preferentially adsorbs on N atom positions in kerogen.CO_(2)is more likely to form hydrogen bonds and adsorb on the surface of kerogen than H_(2)O.As the temperature increases,the number of hydrogen bonds between H_(2)O and kerogen gradually increases,while the increase in pressure reduces the number of hydrogen bonds.Although high pressure helps to increase an amount of CS,it increases the permeability of a cap rock,which is not conducive to CS.Therefore,when determining CO_(2)pressure,not only a storage amount but also the storage safety should be considered.This research method and results help optimize the design of CS technology,and have important significance for achieving sustainable development.展开更多
Urbanization radically alters the climatic environment and landscape patterns of urban areas,but its impact on the carbon sequestration capacity of vegetation remains uncertain.Given the limitations of current small-s...Urbanization radically alters the climatic environment and landscape patterns of urban areas,but its impact on the carbon sequestration capacity of vegetation remains uncertain.Given the limitations of current small-scale ground-based in situ experiments,the response of vegetation carbon sequestration capacity to urbanization and the factors influencing it remain unclear at the global scale.Using multisource remote sensing data,we quanti-fied and differentiated the direct and indirect impacts of urbanization on the carbon sequestration capacity of vegetation in 508 large urban areas globally from 2000 to 2020.The results revealed that the direct impacts of urbanization were generally negative.However,446 cities experienced an indirect enhancement in vegetation carbon sequestration capacity during urbanization,averaging 19.6%globally and offsetting 14.7%of the di-rect loss due to urbanization.These positive indirect effects were most pronounced in environments with limited hydrothermal conditions and increased most in densely populated temperate and cold regions.Furthermore,indi-rect impacts were closely related to urbanization intensity,human footprint,and level of urban development.Our study enhances the understanding of how the carbon sequestration capacity of vegetation dynamically responds to changes in the urban environment,which is crucial for improving future urban vegetation management and building sustainable cities.展开更多
Blue carbon ecosystems,including mangroves,seagrasses,and salt marshes,play a crucial role in mitigating climate change by capturing and storing atmospheric CO_(2)at rates exceeding those of terrestrial forests.This s...Blue carbon ecosystems,including mangroves,seagrasses,and salt marshes,play a crucial role in mitigating climate change by capturing and storing atmospheric CO_(2)at rates exceeding those of terrestrial forests.This study explores the potential of HCWs(Human-Controlled Wetlands)in the Italian Venice Lagoon as an underappreciated component of the global blue carbon pool.Using GEE(Google Earth Engine),we conducted a large-scale assessment of carbon sequestration in these wetlands,demonstrating its advantages over traditional in situ methods in addressing spatial variability.Our findings highlight the significance of below-water mud sediments as primary carbon reservoirs,with a TC(Total Carbon)content of 3.81%±0.94%and a stable storage function akin to peat,reinforced by high CEC(Cation Exchange Capacity).GEE analysis identified a redoximorphic zone at a depth of 20-30 cm,where microbial respiration shifts to anaerobic pathways,preventing carbon release and maintaining long-term sequestration.The study also evaluates key factors affecting remote sensing accuracy,including tidal variations,water depth,and sky cover.The strong correlation between field-measured and satellite-derived carbon parameters(R^(2)>0.85)confirms the reliability of our approach.Furthermore,we developed a GEE-based script for monitoring sediment bioturbation,leveraging Sentinel-1 SAR(Synthetic Aperture Radar)and Sentinel-2 optical data to quantify biological disturbances affecting carbon fluxes.Our results underscore the value of HCWs for carbon sequestration,reinforcing the need for targeted conservation strategies.The scalability and efficiency of remote sensing methodologies,particularly GEE,make them essential for the long-term monitoring of blue carbon ecosystems and the development of effective climate mitigation policies.展开更多
Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehens...Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehensive physical simulation experiments were conducted under varied pressures,coupled with assessments of changes in mineral composition,ion concentrations,pore morphology,permeability,and sequestration capacity before and after experimentation.Simultaneously,a method using NMR T2spectra changes to measure pore volume shift and estimate CO_(2)sequestration is introduced.It quantifies CO_(2)needed for mineralization of soluble minerals.However,when CO_(2)dissolves in crude oil,the precipitation of asphaltene compounds impairs both seepage and storage capacities.Notably,the impact of dissolution and precipitation is closely associated with storage pressure,with a particularly pronounced influence on smaller pores.As pressure levels rise,the magnitude of pore alterations progressively increases.At a pressure threshold of 25 MPa,the rate of change in small pores due to dissolution reaches a maximum of 39.14%,while precipitation results in a change rate of-58.05%for small pores.The observed formation of dissolution pores and micro-cracks during dissolution,coupled with asphaltene precipitation,provides crucial insights for establishing CO_(2)sequestration parameters and optimizing strategies in low permeability reservoirs.展开更多
Understanding the differences in CO_(2)adsorption in cementitious material is critical in mitigating the carbon footprint of the construction industry.This study chose the most common β-C_(2)S phase in the industry a...Understanding the differences in CO_(2)adsorption in cementitious material is critical in mitigating the carbon footprint of the construction industry.This study chose the most common β-C_(2)S phase in the industry as the cementitious material,selecting the β-C_(2)S(111)and β-C_(2)S(100)surfaces for CO_(2)adsorption.First-principles calculations were employed to systematically compare the CO_(2)ad-sorption behaviors on both surfaces focusing on adsorption energy,adsorption configurations,and surface reconstruction.The comparis-on of CO_(2)and H2O adsorption behaviors on the β-C_(2)S(111)surface was also conducted to shed light on the influence of CO_(2)on cement hydration.The adsorption energies of CO_(2)on the β-C_(2)S(111)and β-C_(2)S(100)surfaces were determined as-0.647 and-0.423 eV,respect-ively,suggesting that CO_(2)adsorption is more energetically favorable on the β-C_(2)S(111)surface than on the β-C_(2)S(100)surface.The ad-sorption energy of H2O on the β-C_(2)S(111)surface was-1.588 eV,which is 0.941 eV more negative than that of CO_(2),implying that β-C_(2)S tends to become hydrated before reacting with CO_(2).Bader charges,charge density differences,and the partial density of states were ap-plied to characterize the electronic properties of CO_(2)and H2O molecules and those of the surface atoms.The initial Ca/O sites on the β-C_(2)S(111)surface exhibited higher chemical reactivity due to the greater change in the average number of valence electrons in the CO_(2)ad-sorption.Specifically,after CO_(2)adsorption,the average number of valence electrons for both the Ca and O atoms increased by 0.002 on the β-C_(2)S(111)surface,while both decreased by 0.001 on the β-C_(2)S(100)surface.In addition,due to the lower valence electron number of O atoms,the chemical reactivity of O atoms on the β-C_(2)S(111)surface after H2O adsorption was higher than the case of CO_(2)adsorption,which favors the occurrence of further reactions.Overall,this work assessed the adsorption capacity of the β-C_(2)S surface for CO_(2)mo-lecules,offering a strong theoretical foundation for the design of novel cementitious materials for CO_(2)capture and storage.展开更多
Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compare...Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compared the SOC pool,including recalcitrant organic carbon(ROC)and labile carbon pools,as well as three residual carbon sources(amino sugars,lignin phenols,and lipids)in sediments between mangroves of introduced Sonneratia apetala and native Kandelia obovata,and further connected them with microbial life strategies and C metabolism capability.The results showed that SOC accumulation in S.apetala(SA)sediment was about 30%-50% of that in K.obovata(KO)sediment.ROC was the dominant form of SOC in long-term sequestration(76%-83%),while lignin phenols,amino sugars,and lipids were important sources of ROC.In S.apetala sediments,the ROC content was positively correlated with amino sugars,resulting from the more r-strategist microbes that can rapidly convert plant-derived carbon into microbial biomass,which is subsequently transformed into microbial necromass.In contrast,in K.obovata sediments,ROC content showed a stronger positive correlation with the concentrations of lignin phenols and lipids.More K-strategist fungi in the topsoil of K.obovata increased enzyme activities,while more K-strategist bacteria in the subsoil enhanced carbon utilization capacity,thereby increasing lignin phenols and lipids from plant residues in both soil layers.Meanwhile,higher Ca^(2+)concentrations in K.obovata sediments protected three residual carbons from further microbe decomposition.This study provides valuable insights into the molecular mechanisms of SOC sequestration mediated by microbial life strategies in mangrove ecosystems.展开更多
The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fract...The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fractions.However,there is limited information on the carbon sequestration efficiency(CSE)of chemically separated SOC fractions and its response to OC input under long-term fertilization regimes,especially at different sites.This study used three long-term fertilization experiments in Gongzhuling,Zhengzhou and Qiyang spanning 20 years to compare the stocks and CSE in four different OC fractions(very labile OC,labile OC,less labile OC,and non-labile OC)and their relationships with annual OC input.Three treatments of no fertilization(CK),chemical nitrogen,phosphorous,and potassium fertilizers(NPK),and chemical NPK combined with manure(NPKM)were employed.The results showed that compared with CK,NPKM resulted in enhanced SOC stocks and sequestration rates as well as CSE levels of all fractions irrespective of experimental site.Specifically for the very labile and non-labile OC fractions,NPKM significantly increased the SOC stocks by 43 and 83%,77 and 86%,and 73 and 82%in Gongzhuling,Qiyang,and Zhengzhou relative to CK,respectively.However,the greatest changes in SOC stock relative to the initial value were associated with non-labile OC fractions in Gongzhuling,Zhengzhou,and Qiyang,which reached 6.65,7.16,and 7.35 Mg ha^(-1) under NPKM.Similarly,the highest CSE was noted for non-labile OC fractions under NPKM followed sequentially by the very labile OC,labile OC,and less-labile OC fractions,however a CSE of 8.56%in the non-labile OC fraction for Gongzhuling was higher than the values of 6.10 and 4.61%in Zhengzhou and Qiyang,respectively.In addition,the CSE for the passive pool(very labile+labile OC fractions)was higher than the active pool(less-labile+non-labile OC fractions),with the highest value in Gongzhuling.The redundancy analysis revealed that the CSEs of fractions and pools were negatively influenced by annual OC input,mean annual precipitation and temperature,but positively influenced by the initial SOC and total nitrogen contents.This suggests that differential stability of sequestered OC is further governed by indigenous site characteristics and variable amounts of annual OC input.展开更多
CO_(2)sequestration through steel slag is one of the effective approaches to simultaneously realize the resource utilization of industrial solid waste,reduce carbon emissions,and enhance the stability of steel slag as...CO_(2)sequestration through steel slag is one of the effective approaches to simultaneously realize the resource utilization of industrial solid waste,reduce carbon emissions,and enhance the stability of steel slag as a construction base,with considerable application prospects.Nevertheless,the components responsible for CO_(2)sequestration in steel slag predominantly exist as silicates,whose chemical inertness leads to suboptimal CO_(2)sequestration efficiency in the slag.Based on the strategy of activating the silicate components in steel slag with the alkali metal potassium(K)to improve the CO_(2)sequestration performance of steel slag,both experiments and theoretical calculations were performed to give a deep insight into the effect and mechanism of K modification on enhancing the CO_(2)sequestration capability of steel slag.In experiments,CO_(2)sequestration capacity of steel slag modified with 3 wt.%K reached 100.15 g/kg at 1000 K.Theoretical analysis has revealed that although K exhibits low reactivity,it enhances the electronic transition and amplifies charge localization at specific sites within Ca_(2)SiO_(4),consequently improving its CO_(2)sequestration capacity.However,an excessive doping of K led to the partial inactivation of some active sites within Ca_(2)SiO_(4).Furthermore,CO_(2)chemisorption on Ca_(2)SiO_(4)surface predominantly occurs through the chelate configuration of CO_(3)^(2−),suggesting the formation of a CaCO_(3)precursor.Thus,both the experimental results and theoretical calculations reveal the role of K on enhancing CO_(2)sequestration capability of steel slag.In summary,K modification offers promising prospects for improving CO_(2)sequestration properties of steel slag and provides support for the industrial implementation of carbon sequestration by steel slag.展开更多
基金supported by the National Key R&D Program of China(No.2023YFC3709500).
文摘Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.
基金supported by the National Key Research and Development Program of China(2021YFE0101300 and 2021YFD1901102)the project supported by the Natural Science Basic Research Plan in Shaanxi Province,China(2023-JC-YB-185)the Ningxia Key Research and Development Program,China(2023BCF01018)。
文摘Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas.
文摘This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.
基金financially supported by the 2023 Fundamental Fund of Thailand Science Research and Innovation(TSRI)under the project titled“The Carbon Dioxide Storage in Local Administration Organization Phitsanulok province Database Partner Plant Genetic Conservation Project Under the Royal Initiation of Her Highness Princess Maha Chakri Siridhorn”(Grant No.4366604).
文摘This study investigates carbon dioxide(CO₂)sequestration and biomass distribution across various plant components and land use types in Ban Krang Subdistrict,Mueang District,Phitsanulok Province,with the goal of enhancing carbon management strategies.Field surveys were conducted using 14 plots of 40×40 meters to quantify biomass and estimate CO₂sequestration across different vegetation types.The findings reveal an average CO₂sequestration of 122.81 ton ha⁻¹,with aboveground biomass,particularly stems,contributing the most to carbon storage.Notably,abandoned perennial crops and mixed perennial crops demonstrated the highest sequestration rates,at 657.94 ton ha⁻¹and 613.00 ton ha⁻¹,respectively.In contrast,agricultural lands such as rice paddies and cassava plantations exhibited the lowest sequestration rates,though rice paddies contributed the highest total CO₂sequestration,amounting to 61,119.71 tons,due to their extensive area.The study highlights the critical role of diverse and dense vegetation,particularly perennial crops,in maximizing carbon sequestration.It also underscores the potential for improving carbon storage in agricultural lands through better land management practices.The results suggest that targeted strategies should prioritize high-sequestration land use types while also enhancing carbon storage in low-sequestration areas.By optimizing land use and management practices,the region can significantly increase its carbon storage capacity,contributing to climate change mitigation and promoting long-term ecological sustainability.These insights are crucial for formulating effective carbon management strategies in Ban Krang Subdistrict,as well as in other comparable regions.
基金financially funded by the 14th Five Years Key Programs for Science and Technology Development of China(No.2021YFC2900400)the National Natural Science Foundation of China(Nos.52274151,552104156,52074351,and 22376221)+2 种基金the Science and Technology Innovation Program of Hunan Province,China(No.2021 RC3125)the Natural Science Foundation of Hunan Province,China(No.2024JJ2074)the Young Elite Scientists Sponsorship Program by CAST(No.2023QNRC 001)。
文摘Growing concerns about greenhouse gas emissions from underground mining have intensified the need for carbon reduction strategies at every stage.Shotcrete used in tunnel support presents a promising opportunity for carbon emission reduction.This study investigates the carbon absorption capacity,mechanical strength,and underlying mechanisms of shotcrete when exposed to varying CO_(2)concentrations during the mine support process.Findings reveal that higher CO_(2)concentrations during the initial stages of carbonation curing enhance early strength but may impede long-term strength development.Shotcrete samples exposed to 2vol%CO_(2)for 14 d exhibited a carbonation degree approximately three times higher than those exposed to 0.03vol%CO_(2).A carbonation layer formed in the shotcrete,sequestering CO_(2)as solid carbonates.In practical terms,shotcrete in an underground return-air tunnel absorbed 1.1 kg·m^(2)of CO_(2)over 14 d,equivalent to treating 33 m^(3)of contaminated air.Thus,using shotcrete for CO_(2)curing in return-air tunnels can significantly reduce carbon emissions,contributing to greener and more sustainable mining practices.
基金supported by the National Natural Science Foundation of China(Nos.52204206 and U24A2090)the Fundamental Research Funds for the Central Universities of China(No.2023CDJXY-006).
文摘Geological sequestration of CO_(2)is critical for deep decarbonization,but the geomechanical stability of coal reservoirs remains a major challenge.This study integrates nanoindentation,XRD/SEM-EDS chemo physical characterization and 4D CT visualization to investigate the time-evolving mechanical degradation of bituminous coals with ScCO_(2)injection.The main results show that 4 d of ScCO_(2)treatment caused 50.47%–80.99%increase in load–displacement deformation and 26.92%–76.17%increase in creep depth at peak load,accompanied by 55.01%–63.38%loss in elastic modulus and 52.83%–74.81%reduction in hardness.The degradation exhibited biphasic kinetics,characterized by rapid surface-driven weakening(0–2 d),followed by stabilized matrix-scale pore homogenization(2–4 d).ScCO_(2)preferentially dissolved carbonate minerals(dolomite),driving pore network expansion and interfacial debonding,while silicate minerals resisted dissolution but promoted structural homogenization.These coupled geochemical-mechanical processes reduced the mechanical heterogeneity of the coal and altered its failure modes.The results establish a predictive framework for reservoir stability assessment and provide actionable insights for optimizing CO_(2)enhanced coalbed methane recovery.
基金supported by the National Natural Science Foundation of China(Grant No.52374192)the Henan Province Funds for Distinguished Young Youths(Grant No.242300421013)the Innovative Scientific Research Team Project of Henan Polytechnic University(Grant No.T2024-1).
文摘Mitigating climate change demands innovative solutions,and carbon sequestration technologies are at the forefront.Among these,basalt,a mafic volcanic rock packed with calcium,magnesium,and iron,emerges as a powerful candidate for carbon dioxide(CO_(2))sequestration through mineral carbonation.This method transforms CO_(2)into stable carbonate minerals,ensuring a permanent and environmentally safe storage solution.While extensive research has explored into basalt’s potential under high hydration conditions,the untapped promise of low water content scenarios remains largely unexplored.Our ground-breaking study investigates the mineral carbonation of basalt powder under low water condi-tions using supercritical CO_(2)(sc-CO_(2)).Conducted at 50℃ and 15 MPa with a controlled moisture content of 30%,our experiment spans various time points(0,7,14,21,and 28 days).Utilising advanced X-ray diffraction(XRD)and scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS),we unveil the mineralogical and morphological transformations.The results are striking:even under low water conditions,basalt efficiently forms valuable carbonate minerals such as calcite,siderite,magnesite,and ankerite.The carbonation efficiency evolves over time,reflecting the dynamic transfor-mation of the basalt matrix.These findings offer pivotal insights into optimising CO_(2)sequestration in basalt under low hydration,marking a significant leap toward sustainable carbon capture and storage.
基金supported by the China Scholarship Council(Grant No.202306440152)the CNPC Science and Technology Major Project of the Fourteenth Five-Year Plan(Grant No.2021DJ0101)+1 种基金the Science Foundation of China University of Petroleum,Beijing(Grant No.2462022YXZZ007)the National Natural Science Foundation of China(Grant No.42102145).
文摘As the main factor influencing the flow and preservation of underground fluids,wettability has a profound impact on CO_(2)sequestration(CS).However,the influencing factors and internal interaction mechanisms of shale kerogen wettability remain unclear.In this study,we used molecular dynamics to simulate the influence of temperature,pressure,and salinity on wettability.Furthermore,the results were validated through various methods such as mean square displacement,interaction energy,electrostatic potential energy,hydrogen bonding,van der Waals forces,and electrostatic forces,thereby confirming the reliability of our findings.As temperature increases,water wettability on the surface of kerogen increases.At CO_(2)pressures of 10 and 20 MPa,as the temperature increases,the kerogen wettability changes from CO_(2)wetting to neutral wetting.As the CO_(2)pressure increases,the water wettability on the surface of kerogen weakens.When the pressure is below 7.375 MPa and the temperature is 298 or 313 K,kerogen undergoes a wettability reversal from neutral wetting to CO_(2)wetting.As salinity increases,water wettability weakens.Divalent cations(Mg2+and Ca2+)have a greater impact on wettability than monovalent cations(Na^(+)).Water preferentially adsorbs on N atom positions in kerogen.CO_(2)is more likely to form hydrogen bonds and adsorb on the surface of kerogen than H_(2)O.As the temperature increases,the number of hydrogen bonds between H_(2)O and kerogen gradually increases,while the increase in pressure reduces the number of hydrogen bonds.Although high pressure helps to increase an amount of CS,it increases the permeability of a cap rock,which is not conducive to CS.Therefore,when determining CO_(2)pressure,not only a storage amount but also the storage safety should be considered.This research method and results help optimize the design of CS technology,and have important significance for achieving sustainable development.
基金supported by the National Natural Science Foun-dation of China(Grants No.42471118 and 52078440)the Youth Innovation Promotion Association of CAS(Grant No.2021194).
文摘Urbanization radically alters the climatic environment and landscape patterns of urban areas,but its impact on the carbon sequestration capacity of vegetation remains uncertain.Given the limitations of current small-scale ground-based in situ experiments,the response of vegetation carbon sequestration capacity to urbanization and the factors influencing it remain unclear at the global scale.Using multisource remote sensing data,we quanti-fied and differentiated the direct and indirect impacts of urbanization on the carbon sequestration capacity of vegetation in 508 large urban areas globally from 2000 to 2020.The results revealed that the direct impacts of urbanization were generally negative.However,446 cities experienced an indirect enhancement in vegetation carbon sequestration capacity during urbanization,averaging 19.6%globally and offsetting 14.7%of the di-rect loss due to urbanization.These positive indirect effects were most pronounced in environments with limited hydrothermal conditions and increased most in densely populated temperate and cold regions.Furthermore,indi-rect impacts were closely related to urbanization intensity,human footprint,and level of urban development.Our study enhances the understanding of how the carbon sequestration capacity of vegetation dynamically responds to changes in the urban environment,which is crucial for improving future urban vegetation management and building sustainable cities.
文摘Blue carbon ecosystems,including mangroves,seagrasses,and salt marshes,play a crucial role in mitigating climate change by capturing and storing atmospheric CO_(2)at rates exceeding those of terrestrial forests.This study explores the potential of HCWs(Human-Controlled Wetlands)in the Italian Venice Lagoon as an underappreciated component of the global blue carbon pool.Using GEE(Google Earth Engine),we conducted a large-scale assessment of carbon sequestration in these wetlands,demonstrating its advantages over traditional in situ methods in addressing spatial variability.Our findings highlight the significance of below-water mud sediments as primary carbon reservoirs,with a TC(Total Carbon)content of 3.81%±0.94%and a stable storage function akin to peat,reinforced by high CEC(Cation Exchange Capacity).GEE analysis identified a redoximorphic zone at a depth of 20-30 cm,where microbial respiration shifts to anaerobic pathways,preventing carbon release and maintaining long-term sequestration.The study also evaluates key factors affecting remote sensing accuracy,including tidal variations,water depth,and sky cover.The strong correlation between field-measured and satellite-derived carbon parameters(R^(2)>0.85)confirms the reliability of our approach.Furthermore,we developed a GEE-based script for monitoring sediment bioturbation,leveraging Sentinel-1 SAR(Synthetic Aperture Radar)and Sentinel-2 optical data to quantify biological disturbances affecting carbon fluxes.Our results underscore the value of HCWs for carbon sequestration,reinforcing the need for targeted conservation strategies.The scalability and efficiency of remote sensing methodologies,particularly GEE,make them essential for the long-term monitoring of blue carbon ecosystems and the development of effective climate mitigation policies.
基金support of the National Natural Science Foundation of China(Grant Nos.52174030,52474042 and 52374041)the Postgraduate Innovation Fund Project of Xi'an Shiyou University(No.YCX2411001)the Natural Science Basic Research Program of Shaanxi(Program Nos.2024JCYBMS-256 and 2022JQ-528)。
文摘Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehensive physical simulation experiments were conducted under varied pressures,coupled with assessments of changes in mineral composition,ion concentrations,pore morphology,permeability,and sequestration capacity before and after experimentation.Simultaneously,a method using NMR T2spectra changes to measure pore volume shift and estimate CO_(2)sequestration is introduced.It quantifies CO_(2)needed for mineralization of soluble minerals.However,when CO_(2)dissolves in crude oil,the precipitation of asphaltene compounds impairs both seepage and storage capacities.Notably,the impact of dissolution and precipitation is closely associated with storage pressure,with a particularly pronounced influence on smaller pores.As pressure levels rise,the magnitude of pore alterations progressively increases.At a pressure threshold of 25 MPa,the rate of change in small pores due to dissolution reaches a maximum of 39.14%,while precipitation results in a change rate of-58.05%for small pores.The observed formation of dissolution pores and micro-cracks during dissolution,coupled with asphaltene precipitation,provides crucial insights for establishing CO_(2)sequestration parameters and optimizing strategies in low permeability reservoirs.
基金financially supported by the Natural Sci-ence Foundation of Hunan Province,China(No.2024JJ2074)National Natural Science Foundation of China(No.22376221)+2 种基金Young Elite Scientists Sponsorship Pro-gram by the China Association for Science and Technology(CAST)(No.2023QNRC001)partly supported by the High Performance Computing Center of Central South University,Chinasupported by resources provided by the Pawsey Supercomputing Centre with funding from the Australian Government and the Government of Western Australia.
文摘Understanding the differences in CO_(2)adsorption in cementitious material is critical in mitigating the carbon footprint of the construction industry.This study chose the most common β-C_(2)S phase in the industry as the cementitious material,selecting the β-C_(2)S(111)and β-C_(2)S(100)surfaces for CO_(2)adsorption.First-principles calculations were employed to systematically compare the CO_(2)ad-sorption behaviors on both surfaces focusing on adsorption energy,adsorption configurations,and surface reconstruction.The comparis-on of CO_(2)and H2O adsorption behaviors on the β-C_(2)S(111)surface was also conducted to shed light on the influence of CO_(2)on cement hydration.The adsorption energies of CO_(2)on the β-C_(2)S(111)and β-C_(2)S(100)surfaces were determined as-0.647 and-0.423 eV,respect-ively,suggesting that CO_(2)adsorption is more energetically favorable on the β-C_(2)S(111)surface than on the β-C_(2)S(100)surface.The ad-sorption energy of H2O on the β-C_(2)S(111)surface was-1.588 eV,which is 0.941 eV more negative than that of CO_(2),implying that β-C_(2)S tends to become hydrated before reacting with CO_(2).Bader charges,charge density differences,and the partial density of states were ap-plied to characterize the electronic properties of CO_(2)and H2O molecules and those of the surface atoms.The initial Ca/O sites on the β-C_(2)S(111)surface exhibited higher chemical reactivity due to the greater change in the average number of valence electrons in the CO_(2)ad-sorption.Specifically,after CO_(2)adsorption,the average number of valence electrons for both the Ca and O atoms increased by 0.002 on the β-C_(2)S(111)surface,while both decreased by 0.001 on the β-C_(2)S(100)surface.In addition,due to the lower valence electron number of O atoms,the chemical reactivity of O atoms on the β-C_(2)S(111)surface after H2O adsorption was higher than the case of CO_(2)adsorption,which favors the occurrence of further reactions.Overall,this work assessed the adsorption capacity of the β-C_(2)S surface for CO_(2)mo-lecules,offering a strong theoretical foundation for the design of novel cementitious materials for CO_(2)capture and storage.
基金supported by grants from the National Natural Science Foundation of China(Nos.42076117 and 32160051)the Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515012772,2024A1515011721,and 2024A1515012249).
文摘Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compared the SOC pool,including recalcitrant organic carbon(ROC)and labile carbon pools,as well as three residual carbon sources(amino sugars,lignin phenols,and lipids)in sediments between mangroves of introduced Sonneratia apetala and native Kandelia obovata,and further connected them with microbial life strategies and C metabolism capability.The results showed that SOC accumulation in S.apetala(SA)sediment was about 30%-50% of that in K.obovata(KO)sediment.ROC was the dominant form of SOC in long-term sequestration(76%-83%),while lignin phenols,amino sugars,and lipids were important sources of ROC.In S.apetala sediments,the ROC content was positively correlated with amino sugars,resulting from the more r-strategist microbes that can rapidly convert plant-derived carbon into microbial biomass,which is subsequently transformed into microbial necromass.In contrast,in K.obovata sediments,ROC content showed a stronger positive correlation with the concentrations of lignin phenols and lipids.More K-strategist fungi in the topsoil of K.obovata increased enzyme activities,while more K-strategist bacteria in the subsoil enhanced carbon utilization capacity,thereby increasing lignin phenols and lipids from plant residues in both soil layers.Meanwhile,higher Ca^(2+)concentrations in K.obovata sediments protected three residual carbons from further microbe decomposition.This study provides valuable insights into the molecular mechanisms of SOC sequestration mediated by microbial life strategies in mangrove ecosystems.
基金support from the National Natural Science Foundation of China(42177341)is highly acknowledged。
文摘The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fractions.However,there is limited information on the carbon sequestration efficiency(CSE)of chemically separated SOC fractions and its response to OC input under long-term fertilization regimes,especially at different sites.This study used three long-term fertilization experiments in Gongzhuling,Zhengzhou and Qiyang spanning 20 years to compare the stocks and CSE in four different OC fractions(very labile OC,labile OC,less labile OC,and non-labile OC)and their relationships with annual OC input.Three treatments of no fertilization(CK),chemical nitrogen,phosphorous,and potassium fertilizers(NPK),and chemical NPK combined with manure(NPKM)were employed.The results showed that compared with CK,NPKM resulted in enhanced SOC stocks and sequestration rates as well as CSE levels of all fractions irrespective of experimental site.Specifically for the very labile and non-labile OC fractions,NPKM significantly increased the SOC stocks by 43 and 83%,77 and 86%,and 73 and 82%in Gongzhuling,Qiyang,and Zhengzhou relative to CK,respectively.However,the greatest changes in SOC stock relative to the initial value were associated with non-labile OC fractions in Gongzhuling,Zhengzhou,and Qiyang,which reached 6.65,7.16,and 7.35 Mg ha^(-1) under NPKM.Similarly,the highest CSE was noted for non-labile OC fractions under NPKM followed sequentially by the very labile OC,labile OC,and less-labile OC fractions,however a CSE of 8.56%in the non-labile OC fraction for Gongzhuling was higher than the values of 6.10 and 4.61%in Zhengzhou and Qiyang,respectively.In addition,the CSE for the passive pool(very labile+labile OC fractions)was higher than the active pool(less-labile+non-labile OC fractions),with the highest value in Gongzhuling.The redundancy analysis revealed that the CSEs of fractions and pools were negatively influenced by annual OC input,mean annual precipitation and temperature,but positively influenced by the initial SOC and total nitrogen contents.This suggests that differential stability of sequestered OC is further governed by indigenous site characteristics and variable amounts of annual OC input.
基金supported by China Baowu Low Carbon Metallurgy Innovation Foundation(BWLCF202202)Major Industry Innovation Plan of Anhui Province(AHZDCYCX-LSDT2023-01).
文摘CO_(2)sequestration through steel slag is one of the effective approaches to simultaneously realize the resource utilization of industrial solid waste,reduce carbon emissions,and enhance the stability of steel slag as a construction base,with considerable application prospects.Nevertheless,the components responsible for CO_(2)sequestration in steel slag predominantly exist as silicates,whose chemical inertness leads to suboptimal CO_(2)sequestration efficiency in the slag.Based on the strategy of activating the silicate components in steel slag with the alkali metal potassium(K)to improve the CO_(2)sequestration performance of steel slag,both experiments and theoretical calculations were performed to give a deep insight into the effect and mechanism of K modification on enhancing the CO_(2)sequestration capability of steel slag.In experiments,CO_(2)sequestration capacity of steel slag modified with 3 wt.%K reached 100.15 g/kg at 1000 K.Theoretical analysis has revealed that although K exhibits low reactivity,it enhances the electronic transition and amplifies charge localization at specific sites within Ca_(2)SiO_(4),consequently improving its CO_(2)sequestration capacity.However,an excessive doping of K led to the partial inactivation of some active sites within Ca_(2)SiO_(4).Furthermore,CO_(2)chemisorption on Ca_(2)SiO_(4)surface predominantly occurs through the chelate configuration of CO_(3)^(2−),suggesting the formation of a CaCO_(3)precursor.Thus,both the experimental results and theoretical calculations reveal the role of K on enhancing CO_(2)sequestration capability of steel slag.In summary,K modification offers promising prospects for improving CO_(2)sequestration properties of steel slag and provides support for the industrial implementation of carbon sequestration by steel slag.
