In order to avoid environmental pollution from Coal gangue （CG） and copper tailings （CT）, the utilization as cement clinker calcinations was experimentally investigated. Low-calcium limestone was also selected as ...In order to avoid environmental pollution from Coal gangue （CG） and copper tailings （CT）, the utilization as cement clinker calcinations was experimentally investigated. Low-calcium limestone was also selected as another raw material. The clinker component and microstructure were analyzed by XRD and SEM. The experimental results showed that qualified cement clinker could be generated by substituting CG and CT compound for clay. While mixed with high-calcium limestone and low-calcium limestone, the calcinations temperature were 50 ℃ or 100 ℃ lower than that of clay. CT and CG contain oxygen-rich minerals and potential of geological rock energy. The energy of CG performs functions and drops down sintering temperature. The calcination time was shortened and the clinker sintering coal consumption reduced while substituting CG and CT for clay, and also served the reutilization of low-calcium limestone, CG and CT.展开更多
The transition of the Chinese iron and steel industry to ultralow emissions has accelerated the development of denitrification technologies.Considering the existing dual carbon targets,carbon emissions must be conside...The transition of the Chinese iron and steel industry to ultralow emissions has accelerated the development of denitrification technologies.Considering the existing dual carbon targets,carbon emissions must be considered as a critical indicator when comparing denitrification systems.Consequently,this study provided a comprehensive cost-benefit model for denitrification in the steel industry,encompassing additional carbon emissions resulting from the implementation of denitrification systems.Activated-carbon adsorption and selective catalytic reduction(SCR)systems are two efficient techniques for controlling NOx emissions during sintering.Based on thismodel,a cost-benefit analysis of these two typical systems was conducted,and the results indicated that the unit flue-gas abatement costs of SCR and activated-carbon adsorption systems were 0.00275 and 0.0126 CNY/m^(3),and the unit flue-gas abatement benefits were 0.0072 and 0.0179 CNY/m^(3),respectively.Additionally,the effect of operational characteristics on operating costs,including duration and material prices,was analyzed.When treating the flue gas,the two systems released 0.0020 and 0.0060 kg/m^(3) of carbon dioxide,respectively.The primary sources of carbon emissions from the SCR and activated-carbon adsorption systems are the production of reducing agents and system operations,respectively.Furthermore,considering the features of the activated carbon adsorption system for simultaneous desulfurization,a SCR-wet flue gas desulfurization(WFGD)technology route was developed for comparison with the activated carbon adsorption system.展开更多
A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extract...A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond...展开更多
The catalytic effects of four industrial wastes,namely,the soap residue(SR),brine sludge(BS),calcium carbide residue(CCR),and white lime mud(WLM),on coal thermal ignition were investigated.The acidity of palmitate ani...The catalytic effects of four industrial wastes,namely,the soap residue(SR),brine sludge(BS),calcium carbide residue(CCR),and white lime mud(WLM),on coal thermal ignition were investigated.The acidity of palmitate anion associated with Na+in SR was lower than that of chloride anion combined with Na+in BS,which resulted in an improved the combustion of SR.The acidity of OH-anion combined with Ca2+in CCR was lower than that of CO32-anion combined with Ca2+in WLM,resulting in CCR exhibiting a better catalytic effect on coal ignition.The alkaline metal Na had lower initial ionisation energy than the alkaline earth metal Ca.Therefore,the Na-rich SR exhibited higher catalytic activity on coal ignition than Ca-rich CCR.The ignition temperature of coal with 0.5%SR decreased from 544 to 503°C.展开更多
Bamboo was a popular material substituting for wood, especially for one-off commodity in China. In order to recover energy and materials from waste bamboo, the basic characteristics of bamboo pyrolysis were studied by...Bamboo was a popular material substituting for wood, especially for one-off commodity in China. In order to recover energy and materials from waste bamboo, the basic characteristics of bamboo pyrolysis were studied by a thermogravimetric analyzer. It implied that the reaction began at 190-210℃, and the percentage of solid product deceased from about 25% to 17% when temperature ranged from 400℃ to 700℃. A lab-scale fluidized-bed furnace was setup to research the detailed properties of gaseous, liquid and solid products respectively. When temperature increased from 400℃ to 700℃, the mass percent of solid product decreased from 27% to 17% approximately, while that of syngas rose up from 19% to 35%. When temperature was about 500℃, the percentage of tar reached the top, about 31%. The mass balance of these experiments was about 93%-95%. It indicated that three reactions involved in the process： pyrolysis of exterior bamboo, pyrolysis of interior bamboo and secondary pyrolysis of heavy tar.展开更多
The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese co...The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted.Detailed data were collected from 30 ultra-low emission coal-fired units across China.Based on a cost analysis model,the average unit power generation incremental costs were 0.0144and 0.0095 CNY/(kW·hr)for SO_(2)and NOx control technologies,respectively.The unit power generation incremental cost of twin spray tower technology was 7.2%higher than that of dual-loop spray tower technology.The effect of key parameters on operating cost was analyzed.The unit power generation incremental cost increased because of increments in the electricity price for SO_(2)control technology and the price of the reductant in NOx control technology.With high sulfur content or NOx concentration,the unit power generation incremental cost caused by pollutant control increased,whereas the unit pollutant abatement cost decreased.However,the annual operating hours or load increased,thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost.展开更多
Ships and other mobile pollution sources emitted massive ultrafine and low-resistivity particles containing black carbon(BC),which were harmful to human health and were difficult to capture by conventional electrostat...Ships and other mobile pollution sources emitted massive ultrafine and low-resistivity particles containing black carbon(BC),which were harmful to human health and were difficult to capture by conventional electrostatic precipitators(ESPs).In this study,nanoscale carbon black was adopted as simulated particles(SP)with similar physicochemical properties for black carbon emitted from ships(SP-BC)to investigate the feasibility of using an ESP with square-grooved collecting plates for the removal of SP-BC at low backpressures.The increased applied voltage significantly improved the total collection of SP-BC whereas may also promote the conversion of relatively larger particle size SP-BC into nano-size below 20nm.The outlet number concentration of SP-BC under 27 kV at 130℃was three times that of the inlet.While the reduction of the flow rate could strengthen the capture of SP-BC below20 nm,and under the combined action of low flow rate and maximum applied voltage,the collection efficiency of 20-100 nm SP-BC could exceed 90%.In addition,the escape and capture characteristics of SP-BC under long-term rapping were revealed.The square-grooved collecting plate could effectively restrain the re-entrainment of collected SP-BC generated by rapping,and the nanoscale SP-BC was trapped in the grooves after rapping.The results could provide insights into the profound removal of massive nanoscale black carbon emissions from mobile sources.展开更多
Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in mariti...Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future.展开更多
The serious air pollution problems in China have significantly affected the development of China’s economy and society,especially in key areas such as Beijing-Tianjin-Hebei,Yangtze River Delta,and Pearl River Delta,w...The serious air pollution problems in China have significantly affected the development of China’s economy and society,especially in key areas such as Beijing-Tianjin-Hebei,Yangtze River Delta,and Pearl River Delta,which has aroused widespread concern throughout society.With the launch of the MOST(Ministry Of Science and Technology)key project for Air Pollution Formation Mechanism and Control Technology during the 13thFive-Year Plan.展开更多
Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separ...Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and recover fine particles from the flue gas of heavy metal smelting processes,including copper,lead and zinc.Significant improvements have been realized in wet scrubbing technology for removing mercury,fluoride and SO_(2)from flue gas.Gas-liquid sulfidation technology by applying H_(2)S was invented to recycle the acid scrubbing wastewater more efficiently and in an eco-friendly manner.Based on digital technology,a source reduction method was designed for sulfur and fluoride control during the whole aluminum electrolysis process.New desulfurization technologies were developed for catalytic reduction of the sulfur content in petroleum coke at low temperature and catalytic reduction of SO_(2)to elemental sulfur.This work has established the technology for coupling multi-pollutant control and resource recovery from the flue gas from non-ferrous metallurgy,which provides the scientific theoretical basis and application technology for the treatment of air pollutants in the non-ferrous metallurgy industry.展开更多
Extreme weather and natural disasters have plagued people for a long time,and ensuring power source provision in such emergency situations is an urgent problem that needs to be solved.Combustion powered thermoelectric...Extreme weather and natural disasters have plagued people for a long time,and ensuring power source provision in such emergency situations is an urgent problem that needs to be solved.Combustion powered thermoelectric generator(CPTEG)is a promising solution to the power supply problem in off-grid areas and under emergency conditions.Adding hydrogen into the fuel is one of the effective ways to reduce carbon dioxide in the context of"Emission Peak”and“Carbon Neutrality”.In this study,the feasibility of the blended propane-hydrogen to power up a CPTEG is investigated,filling a research gap of standalone hydrogen CPTEG with an input power of kilowatt level.The combustion characteristics and the CPTEG performance at different hydrogen ratios(0%-50%)were investigated,including the combustion temperature,hot-/cold-end temperatures,electric power,thermoelectric efficiency(electric power related to the heat flow rate passing through the thermoelectric module),systematic efficiency,and system effectiveness(EFS).Experimental results showed that the combustion is stable and a blue flame is anchored when the hydrogen ratio is less than 45%under the input power of 800 W,whereas the combustion becomes unstable and a bright yellow flame is detected when the hydrogen ratio exceeds 45%.The hydrogen addition considerably affects the CPTEG performance.The electric power is decreased by 13.0%(3.8 W)under the hydrogen ratio of 45%compared to that generated by burning pure propane when the input power is 800 W.The hydrogen addition impacts the combustion characteristics of CPTEG.The combustion stability has been improved,which is contributed by the reduced coefficient of variation.It is found that the standard deviation(SD)and coefficient of variation(COV)of flame temperature both sharply decreased by 66.8%under the hydrogen ratio of 45%.In addition,the hydrogen addition impact the carbon dioxide in the exhaust gas of CPTEG,and the CO_(2)concentration decreased by 11.5%under the hydrogen ratio of 45%.Furthermore,the total electric power and thermoelectric efficiency of the developed CPTEG are 32.4 W and3.24%,respectively.展开更多
To obtain a deeper understanding of the mass transfer between MgO-based sorbent particles and gaseous reactants(CO_(2)),it is essential to investigate the mass transfer characteristics of a single moving sorbent parti...To obtain a deeper understanding of the mass transfer between MgO-based sorbent particles and gaseous reactants(CO_(2)),it is essential to investigate the mass transfer characteristics of a single moving sorbent particle since most previous researches focused on the removal efficiency of the whole flow field and ignored the behavior of individual particles.Currently,most studies assumed that the reactant(CO_(2))concentration across the particle surface is uniform based on the average concentration within the grid,while the reactant concentration on the particle surface changes as the particle moves.In this study,the gas-solid mass transfer between CO_(2) and a moving MgO-based particle was investigated.The results indicated that the motion state and velocity of the particles significantly impact the CO_(2) removal dy-namics and noticeable differences in the CO_(2) concentration gradient could be observed around the particle.Increasing the reaction temperature,enhancing the CO_(2) mass fraction at the inlet,appropriately increasing the gas velocity,and selecting an appropriate particle size can significantly enhance the re-action rate,thereby improving the CO_(2) removal efficiency.The correction formula for surface CO_(2) con-centration and mass transfer reaction rate was also proposed based on the particle's velocity and direction of movement.Based on the correction formula,more detailed guidance for optimizing reactor design could be obtained and the findings provide theoretical guide for designing CO_(2) removal reactors.展开更多
A filtered density function (FDF) transport equation was derived for the fluid velocity seen by the particles in gas-particle two-phase flow. An LES/FDF simulation of a two-phase plane wake flow was carried out. The s...A filtered density function (FDF) transport equation was derived for the fluid velocity seen by the particles in gas-particle two-phase flow. An LES/FDF simulation of a two-phase plane wake flow was carried out. The simulation results were compared with both the experimental photograph and the simulation results without using the FDF model, and proved that the LES/FDF model can clearly improve the spatial dispersion of the particle phase.展开更多
An LES/FDF model was developed by the authors to investigate the SGS effect on the particle motion in the gas-particle two-phase plane wake flow.The simulation results of dispersion rate for different particles were c...An LES/FDF model was developed by the authors to investigate the SGS effect on the particle motion in the gas-particle two-phase plane wake flow.The simulation results of dispersion rate for different particles were compared with the results without using the FDF model.It was shown that the large eddy structure is the dominant factor influencing the particle diffu-sion in space for small particles(small Stokes-number particles),but for intermediate or large diameter particles,the influence of the sub-grid scale eddies on the dispersion rate is in the same order as that of the large eddies.The sub-grid scale eddies increase the particle dispersion rate in most time,but sometimes they decrease the dispersion rate.The sub-grid scale particle dispersion rate is decided not only by the intensity of sub-grid scale eddies and the Stokes number of the particles,but also by the large eddy structure of the flow field.For the particles in isotropic turbulence,the dispersion rate decreases as the particle diameter increases.展开更多
Pyrolysis kinetics were used in this study to analyze the pore formation mechanism of coal activated with KOH.Experimental derivative thermogravimetry(DTG)curves were fitted using Achar and Coats–Redfern methods to o...Pyrolysis kinetics were used in this study to analyze the pore formation mechanism of coal activated with KOH.Experimental derivative thermogravimetry(DTG)curves were fitted using Achar and Coats–Redfern methods to obtain kinetic parameters,such as activation energies.The effects of heating rate and KOH ratio on the activation energy show similar trends.Another attempt was trying to correlate the activation energies with the textural properties.The direct fitting was initially used and the obtained activation energies showed little correlation with textural properties.Two improved methods,namely,single peak fitting and multi peak fitting,were introduced.The former only considered the interaction between KOH and coal,regardless of coal pyrolysis.The activation energies obtained showed linear relation with the total pore volumes/BET(Brunauer–Emmett–Teller)surface areas(R^(2)=0.94/0.99).The latter used Gaussian function to deconvolute the DTG curves,and then,each theoretical DTG peak could be correctly fitted.The positive linear correlation between the summed activation energies derived from surface reactions and metallic K intercalation and micropore volumes/surface areas was obtained(R^(2)=0.993/0.996).Therefore,the proposed methods could be successfully applied to design and analyze the textural properties of specific coals with KOH activation.展开更多
Proton exchange membrane water electrolyzer(PEMWE)driven by renewable electricity is a promising technique toward green hydrogen production,but the corrosive environment and high working potential pose severe challeng...Proton exchange membrane water electrolyzer(PEMWE)driven by renewable electricity is a promising technique toward green hydrogen production,but the corrosive environment and high working potential pose severe challenges for developing advanced electrocatalysts for the oxygen evolution reaction(OER).Although Ir-based materials possess relatively balanced activity and stability for the OER,their dissolution behavior cannot be neglected,in particular under high working potentials.In this work,iridium dioxide(IrO_(2))nanoparticles(NPs)were anchored on the surface of exfoliated h-boron nitride(BN)nanosheets(NSs)toward the OER reaction in acid media.Highly active Ir(V)species were stabilized by the epitaxial interface between IrO_(2)and h-BN,and therefore the IrO_(2)/BN delivered stable performance at increased working potentials,while the activity of bare IrO_(2)NPs without h-BN support decreased rapidly.Also,the smaller lattice spacing of h-BN induced compressive strain for IrO_(2),resulting in improved activity.Our results demonstrate the feasibility of stabilizing highly active Ir(V)species for the OER in acid media by constructing robust interface and provide new possibilities toward designing advanced heterostructured electrocatalysts.展开更多
Calibration of the relationship between the scattering angle and the CCD pixel is a key part of achieving accurate measurements of rainbow refractometry.A novel self-calibrated global rainbow refractometry system base...Calibration of the relationship between the scattering angle and the CCD pixel is a key part of achieving accurate measurements of rainbow refractometry.A novel self-calibrated global rainbow refractometry system based on illumination by two lasers of different wavelengths is proposed.The angular calibration and refractive index measurement of two wavelengths can be completed simultaneously without extra measurement devices.The numerical and experimental results show the feasibility and high precision of the self-calibration method,which enables the rainbow refractometry to be implemented in a more powerful and convenient way.The self-calibrated rainbow system is successfully applied to measure the refractive indices of ethanol-water solutions with volume concentrations of 10% to 60%.展开更多
基金Funded by the "11th-Five-Year" National Key Technologies R&D Program of China (No.2006BAC21B02)
文摘In order to avoid environmental pollution from Coal gangue （CG） and copper tailings （CT）, the utilization as cement clinker calcinations was experimentally investigated. Low-calcium limestone was also selected as another raw material. The clinker component and microstructure were analyzed by XRD and SEM. The experimental results showed that qualified cement clinker could be generated by substituting CG and CT compound for clay. While mixed with high-calcium limestone and low-calcium limestone, the calcinations temperature were 50 ℃ or 100 ℃ lower than that of clay. CT and CG contain oxygen-rich minerals and potential of geological rock energy. The energy of CG performs functions and drops down sintering temperature. The calcination time was shortened and the clinker sintering coal consumption reduced while substituting CG and CT for clay, and also served the reutilization of low-calcium limestone, CG and CT.
基金supported by the National Key Research and Development Program of China(No.2022YFC3703403)Zhejiang Provincial“LeadWild Goose”Research and Development Project(No.2022C03073).
文摘The transition of the Chinese iron and steel industry to ultralow emissions has accelerated the development of denitrification technologies.Considering the existing dual carbon targets,carbon emissions must be considered as a critical indicator when comparing denitrification systems.Consequently,this study provided a comprehensive cost-benefit model for denitrification in the steel industry,encompassing additional carbon emissions resulting from the implementation of denitrification systems.Activated-carbon adsorption and selective catalytic reduction(SCR)systems are two efficient techniques for controlling NOx emissions during sintering.Based on thismodel,a cost-benefit analysis of these two typical systems was conducted,and the results indicated that the unit flue-gas abatement costs of SCR and activated-carbon adsorption systems were 0.00275 and 0.0126 CNY/m^(3),and the unit flue-gas abatement benefits were 0.0072 and 0.0179 CNY/m^(3),respectively.Additionally,the effect of operational characteristics on operating costs,including duration and material prices,was analyzed.When treating the flue gas,the two systems released 0.0020 and 0.0060 kg/m^(3) of carbon dioxide,respectively.The primary sources of carbon emissions from the SCR and activated-carbon adsorption systems are the production of reducing agents and system operations,respectively.Furthermore,considering the features of the activated carbon adsorption system for simultaneous desulfurization,a SCR-wet flue gas desulfurization(WFGD)technology route was developed for comparison with the activated carbon adsorption system.
基金the National NaturalScience Foundation (No. 30570053)the Fund of CrossSubjects of Zhejiang University (No. 109000-812651)+2 种基金the National Natural Science Foundation of China (No.50406022)the National High Technology Research and Development Program of China (No. 2007AA10Z409)the National Key Project of Scientific and Technical Supporting Programs Funded by Ministry of Science &Technology of China (No. 2006BAJ08B01)
文摘A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond...
基金Supported by the National Key Research and Development Program of China(2016YFB0600505)the National Natural Science Foundation of China(51676171).
文摘The catalytic effects of four industrial wastes,namely,the soap residue(SR),brine sludge(BS),calcium carbide residue(CCR),and white lime mud(WLM),on coal thermal ignition were investigated.The acidity of palmitate anion associated with Na+in SR was lower than that of chloride anion combined with Na+in BS,which resulted in an improved the combustion of SR.The acidity of OH-anion combined with Ca2+in CCR was lower than that of CO32-anion combined with Ca2+in WLM,resulting in CCR exhibiting a better catalytic effect on coal ignition.The alkaline metal Na had lower initial ionisation energy than the alkaline earth metal Ca.Therefore,the Na-rich SR exhibited higher catalytic activity on coal ignition than Ca-rich CCR.The ignition temperature of coal with 0.5%SR decreased from 544 to 503°C.
基金Project supported by the National Basic Research Program (973) of China (Nos. G199902210534, 2005CB221202 and 2007CB210208)the Hi-Tech Research and Development Program (863) of China (No. 2006AA020101)the Open Foundation of State Key Laboratory of Clean Energy Utilization of China (No. ZJUCEU2006004)
文摘Bamboo was a popular material substituting for wood, especially for one-off commodity in China. In order to recover energy and materials from waste bamboo, the basic characteristics of bamboo pyrolysis were studied by a thermogravimetric analyzer. It implied that the reaction began at 190-210℃, and the percentage of solid product deceased from about 25% to 17% when temperature ranged from 400℃ to 700℃. A lab-scale fluidized-bed furnace was setup to research the detailed properties of gaseous, liquid and solid products respectively. When temperature increased from 400℃ to 700℃, the mass percent of solid product decreased from 27% to 17% approximately, while that of syngas rose up from 19% to 35%. When temperature was about 500℃, the percentage of tar reached the top, about 31%. The mass balance of these experiments was about 93%-95%. It indicated that three reactions involved in the process： pyrolysis of exterior bamboo, pyrolysis of interior bamboo and secondary pyrolysis of heavy tar.
基金supported by the National Key Research and Development Program of China(No.2019YFC0214803)Zhejiang Provincial Natural Science Foundation of China(No.LQ21D050002).
文摘The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted.Detailed data were collected from 30 ultra-low emission coal-fired units across China.Based on a cost analysis model,the average unit power generation incremental costs were 0.0144and 0.0095 CNY/(kW·hr)for SO_(2)and NOx control technologies,respectively.The unit power generation incremental cost of twin spray tower technology was 7.2%higher than that of dual-loop spray tower technology.The effect of key parameters on operating cost was analyzed.The unit power generation incremental cost increased because of increments in the electricity price for SO_(2)control technology and the price of the reductant in NOx control technology.With high sulfur content or NOx concentration,the unit power generation incremental cost caused by pollutant control increased,whereas the unit pollutant abatement cost decreased.However,the annual operating hours or load increased,thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost.
基金supported by the National Natural Science Foundation (No.52076191)Key Research&Development Plan of Shandong Province (No.2020CXGC011401)。
文摘Ships and other mobile pollution sources emitted massive ultrafine and low-resistivity particles containing black carbon(BC),which were harmful to human health and were difficult to capture by conventional electrostatic precipitators(ESPs).In this study,nanoscale carbon black was adopted as simulated particles(SP)with similar physicochemical properties for black carbon emitted from ships(SP-BC)to investigate the feasibility of using an ESP with square-grooved collecting plates for the removal of SP-BC at low backpressures.The increased applied voltage significantly improved the total collection of SP-BC whereas may also promote the conversion of relatively larger particle size SP-BC into nano-size below 20nm.The outlet number concentration of SP-BC under 27 kV at 130℃was three times that of the inlet.While the reduction of the flow rate could strengthen the capture of SP-BC below20 nm,and under the combined action of low flow rate and maximum applied voltage,the collection efficiency of 20-100 nm SP-BC could exceed 90%.In addition,the escape and capture characteristics of SP-BC under long-term rapping were revealed.The square-grooved collecting plate could effectively restrain the re-entrainment of collected SP-BC generated by rapping,and the nanoscale SP-BC was trapped in the grooves after rapping.The results could provide insights into the profound removal of massive nanoscale black carbon emissions from mobile sources.
基金supported by the National Key R&D Program of China(No.2022YFC3701500)the Key R&D Plan Projects of Zhejiang Province(No.2024SSYS0072)Zhejiang Provincial Natural Science Foundation(No.LDT23E0601).
文摘Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future.
文摘The serious air pollution problems in China have significantly affected the development of China’s economy and society,especially in key areas such as Beijing-Tianjin-Hebei,Yangtze River Delta,and Pearl River Delta,which has aroused widespread concern throughout society.With the launch of the MOST(Ministry Of Science and Technology)key project for Air Pollution Formation Mechanism and Control Technology during the 13thFive-Year Plan.
基金supported by the National Natural Science Foundation of China(No.52234011)the National Key R&D Program of China(No.2017YFC0210400)。
文摘Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and recover fine particles from the flue gas of heavy metal smelting processes,including copper,lead and zinc.Significant improvements have been realized in wet scrubbing technology for removing mercury,fluoride and SO_(2)from flue gas.Gas-liquid sulfidation technology by applying H_(2)S was invented to recycle the acid scrubbing wastewater more efficiently and in an eco-friendly manner.Based on digital technology,a source reduction method was designed for sulfur and fluoride control during the whole aluminum electrolysis process.New desulfurization technologies were developed for catalytic reduction of the sulfur content in petroleum coke at low temperature and catalytic reduction of SO_(2)to elemental sulfur.This work has established the technology for coupling multi-pollutant control and resource recovery from the flue gas from non-ferrous metallurgy,which provides the scientific theoretical basis and application technology for the treatment of air pollutants in the non-ferrous metallurgy industry.
基金supported by Natural Science Foundation of Zhejiang Province(Grant no.LQZSZ24E060001)Hangzhou Key Scientific Research Program Project(2023 SZD0082)+1 种基金"Pioneer"and"Leading Goose"R&D Program of Zhejiang(No.2024C03116)Graduate Research Innovation Foundation of Zhejiang University of Science and Technology(2023yjskc01).
文摘Extreme weather and natural disasters have plagued people for a long time,and ensuring power source provision in such emergency situations is an urgent problem that needs to be solved.Combustion powered thermoelectric generator(CPTEG)is a promising solution to the power supply problem in off-grid areas and under emergency conditions.Adding hydrogen into the fuel is one of the effective ways to reduce carbon dioxide in the context of"Emission Peak”and“Carbon Neutrality”.In this study,the feasibility of the blended propane-hydrogen to power up a CPTEG is investigated,filling a research gap of standalone hydrogen CPTEG with an input power of kilowatt level.The combustion characteristics and the CPTEG performance at different hydrogen ratios(0%-50%)were investigated,including the combustion temperature,hot-/cold-end temperatures,electric power,thermoelectric efficiency(electric power related to the heat flow rate passing through the thermoelectric module),systematic efficiency,and system effectiveness(EFS).Experimental results showed that the combustion is stable and a blue flame is anchored when the hydrogen ratio is less than 45%under the input power of 800 W,whereas the combustion becomes unstable and a bright yellow flame is detected when the hydrogen ratio exceeds 45%.The hydrogen addition considerably affects the CPTEG performance.The electric power is decreased by 13.0%(3.8 W)under the hydrogen ratio of 45%compared to that generated by burning pure propane when the input power is 800 W.The hydrogen addition impacts the combustion characteristics of CPTEG.The combustion stability has been improved,which is contributed by the reduced coefficient of variation.It is found that the standard deviation(SD)and coefficient of variation(COV)of flame temperature both sharply decreased by 66.8%under the hydrogen ratio of 45%.In addition,the hydrogen addition impact the carbon dioxide in the exhaust gas of CPTEG,and the CO_(2)concentration decreased by 11.5%under the hydrogen ratio of 45%.Furthermore,the total electric power and thermoelectric efficiency of the developed CPTEG are 32.4 W and3.24%,respectively.
基金supported by the National Key R&D Program of China(grant No.2022YFC3701500)Zhejiang Provincial Natural Science Foundation of China(grant No.LDT23E0601).
文摘To obtain a deeper understanding of the mass transfer between MgO-based sorbent particles and gaseous reactants(CO_(2)),it is essential to investigate the mass transfer characteristics of a single moving sorbent particle since most previous researches focused on the removal efficiency of the whole flow field and ignored the behavior of individual particles.Currently,most studies assumed that the reactant(CO_(2))concentration across the particle surface is uniform based on the average concentration within the grid,while the reactant concentration on the particle surface changes as the particle moves.In this study,the gas-solid mass transfer between CO_(2) and a moving MgO-based particle was investigated.The results indicated that the motion state and velocity of the particles significantly impact the CO_(2) removal dy-namics and noticeable differences in the CO_(2) concentration gradient could be observed around the particle.Increasing the reaction temperature,enhancing the CO_(2) mass fraction at the inlet,appropriately increasing the gas velocity,and selecting an appropriate particle size can significantly enhance the re-action rate,thereby improving the CO_(2) removal efficiency.The correction formula for surface CO_(2) con-centration and mass transfer reaction rate was also proposed based on the particle's velocity and direction of movement.Based on the correction formula,more detailed guidance for optimizing reactor design could be obtained and the findings provide theoretical guide for designing CO_(2) removal reactors.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 10502044, 10772162, 50736006)
文摘A filtered density function (FDF) transport equation was derived for the fluid velocity seen by the particles in gas-particle two-phase flow. An LES/FDF simulation of a two-phase plane wake flow was carried out. The simulation results were compared with both the experimental photograph and the simulation results without using the FDF model, and proved that the LES/FDF model can clearly improve the spatial dispersion of the particle phase.
基金supported by the National Natural Science Foundation of China(Grant No.10502044,10772162)the Defense-based research project(Grant No.A1420080144)the Major projects on control and rectification of water body pollution(Grant No.2009ZX07424-001)
文摘An LES/FDF model was developed by the authors to investigate the SGS effect on the particle motion in the gas-particle two-phase plane wake flow.The simulation results of dispersion rate for different particles were compared with the results without using the FDF model.It was shown that the large eddy structure is the dominant factor influencing the particle diffu-sion in space for small particles(small Stokes-number particles),but for intermediate or large diameter particles,the influence of the sub-grid scale eddies on the dispersion rate is in the same order as that of the large eddies.The sub-grid scale eddies increase the particle dispersion rate in most time,but sometimes they decrease the dispersion rate.The sub-grid scale particle dispersion rate is decided not only by the intensity of sub-grid scale eddies and the Stokes number of the particles,but also by the large eddy structure of the flow field.For the particles in isotropic turbulence,the dispersion rate decreases as the particle diameter increases.
基金supported by the National Key Research and Development Program of China(No.2022YFB4100201)the Key R&D Program of Zhejiang Province(No.2022C03030)the National Natural Science Foundation of China(Nos.52206119,42341208).
文摘Pyrolysis kinetics were used in this study to analyze the pore formation mechanism of coal activated with KOH.Experimental derivative thermogravimetry(DTG)curves were fitted using Achar and Coats–Redfern methods to obtain kinetic parameters,such as activation energies.The effects of heating rate and KOH ratio on the activation energy show similar trends.Another attempt was trying to correlate the activation energies with the textural properties.The direct fitting was initially used and the obtained activation energies showed little correlation with textural properties.Two improved methods,namely,single peak fitting and multi peak fitting,were introduced.The former only considered the interaction between KOH and coal,regardless of coal pyrolysis.The activation energies obtained showed linear relation with the total pore volumes/BET(Brunauer–Emmett–Teller)surface areas(R^(2)=0.94/0.99).The latter used Gaussian function to deconvolute the DTG curves,and then,each theoretical DTG peak could be correctly fitted.The positive linear correlation between the summed activation energies derived from surface reactions and metallic K intercalation and micropore volumes/surface areas was obtained(R^(2)=0.993/0.996).Therefore,the proposed methods could be successfully applied to design and analyze the textural properties of specific coals with KOH activation.
基金supported by the Natural Science Foundation of Zhejiang Province(No.LZ22B030006)the National Natural Science Foundation of China(No.52171224)+2 种基金G.Q.Z.acknowledges the financial support from the China Postdoctoral Science Foundation(Nos.2021M690132 and 2021T140588)the Office of China Postdoc Council(No.YJ20200160)Natural Science Foundation of Zhejiang Province(No.LQ22B030005).
文摘Proton exchange membrane water electrolyzer(PEMWE)driven by renewable electricity is a promising technique toward green hydrogen production,but the corrosive environment and high working potential pose severe challenges for developing advanced electrocatalysts for the oxygen evolution reaction(OER).Although Ir-based materials possess relatively balanced activity and stability for the OER,their dissolution behavior cannot be neglected,in particular under high working potentials.In this work,iridium dioxide(IrO_(2))nanoparticles(NPs)were anchored on the surface of exfoliated h-boron nitride(BN)nanosheets(NSs)toward the OER reaction in acid media.Highly active Ir(V)species were stabilized by the epitaxial interface between IrO_(2)and h-BN,and therefore the IrO_(2)/BN delivered stable performance at increased working potentials,while the activity of bare IrO_(2)NPs without h-BN support decreased rapidly.Also,the smaller lattice spacing of h-BN induced compressive strain for IrO_(2),resulting in improved activity.Our results demonstrate the feasibility of stabilizing highly active Ir(V)species for the OER in acid media by constructing robust interface and provide new possibilities toward designing advanced heterostructured electrocatalysts.
基金supported by the National Natural Science Foundation of China(No.51576177)the Major Program of the National Natural Science Foundation of China(No.51390491)+1 种基金the National Basic Research Program of China(No.2015CB251501)the Program of Introducing Talents of Discipline to University(No.B08026)
文摘Calibration of the relationship between the scattering angle and the CCD pixel is a key part of achieving accurate measurements of rainbow refractometry.A novel self-calibrated global rainbow refractometry system based on illumination by two lasers of different wavelengths is proposed.The angular calibration and refractive index measurement of two wavelengths can be completed simultaneously without extra measurement devices.The numerical and experimental results show the feasibility and high precision of the self-calibration method,which enables the rainbow refractometry to be implemented in a more powerful and convenient way.The self-calibrated rainbow system is successfully applied to measure the refractive indices of ethanol-water solutions with volume concentrations of 10% to 60%.
