Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting beca...Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting because of its appropriate band structure,non-toxicity,high stability,and low cost.Nevertheless,its relatively low photochemical conversion efficiency limits its application,and enhancing its PEC water splitting efficiency remains a challenge.Consequently,increasing efforts have been rendered toward improving the performance of hematite photoanodes.The entire PEC water splitting efficiency typically includes three parts:the photon absorption efficiency,the separation efficiency of the semiconductor bulk,and the surface injection efficiency.This review briefly discusses the recent advances in studies on hematite photoanodes for water splitting,and through the enhancement of the three above-mentioned efficiencies,the corresponding strategies toward improving the PEC performance of hematite are comprehensively discussed and summarized.展开更多
Sand production often leads to the failure of production equipment on offshore platform.Therefore,a new idea has been put forward,which is installing cyclone or baffle in the internal of the slug catcher for better sa...Sand production often leads to the failure of production equipment on offshore platform.Therefore,a new idea has been put forward,which is installing cyclone or baffle in the internal of the slug catcher for better sand control.In this paper,an experimental study is presented,which mainly includes sand particles accumulation shape,migration law and separation performance.The results suggest that the accumulation area is mainly divided into two zones:the crowded settlement zone and the free settlement zone.The crowded settlement zone has a special shape,which can be characterized by two parameters:accumulation length and accumulation angle.Axial sampling analysis shows obvious particle classification.Median particle size decreases with the increase of the axial distance,and the range of particle size distribution narrows gradually.The separation experiment shows that the gas velocity has the greatest influence on the separation efficiency.When the gas velocity is 14 m·s^ 1,the separation efficiency drops sharply,which can be abated by installing cyclone separator.In addition,the separation efficiency tends to be a constant under different gas velocities by installing baffle with appropriate height.Then the effectiveness and rationality of installing internal components can be strongly proved.All these provide important guidance for maximizing the sand control function of the slug catcher.展开更多
The limitations of swirl separation in removing microfine oil droplets in water have driven the development of hydrocyclone technology coupled with multiphase or multifield techniques.To enhance microfine oil droplets...The limitations of swirl separation in removing microfine oil droplets in water have driven the development of hydrocyclone technology coupled with multiphase or multifield techniques.To enhance microfine oil droplets separation,a novel hydrocyclone separation coupled with fiber coalescence(HCCFC) was designed.The interaction between fiber balls and oil droplets inside the hydrocyclone,including droplet coalescence and breakage,was investigated.The influence of different operating parameters on separation efficiency was discussed.The results showed that fiber balls promoted oil droplet coalescence when the inlet droplet size(D_(43)) was below 22.37 μm but caused droplet breakage above this threshold.The coalescence performance of HCCFC improved with increasing inlet oil content but declined beyond 450 mg·L^(-1).Separation experiments confirmed that HCCFC outperformed conventional hydrocyclone,with separation efficiency increasing by 2.9% to 20.0%.As the fiber ball content and inlet flow rate increased,the separation efficiency showed a trend of first increasing and then decreasing.Additionally,HCCFC's separation efficiency varied with inlet oil droplet size distribution,showing the most significant enhancement when D_(43) was 22.37 μm,where separation efficiency increased by 14.4%.These findings offer insights into the development and application of multiphase coupled with hydrocyclone technology.展开更多
CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hi...CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.展开更多
Photocatalytic reduction of CO_(2)into high-value C_(2)H_(4)offers a promising pathway toward carbon neutrality.Due to the continuous 12-electron-proton coupled reactions and the mutual repulsion of reaction intermedi...Photocatalytic reduction of CO_(2)into high-value C_(2)H_(4)offers a promising pathway toward carbon neutrality.Due to the continuous 12-electron-proton coupled reactions and the mutual repulsion of reaction intermediates,achieving highly selective photocatalytic conversion of CO_(2)to C_(2)H_(4)remains challenging.This work synthesized a CuInS_(2)/CuS heterojunction photocatalyst mediated by a sulfur electron bridge via a one-step solvothermal method,achieving a high selectivity for C_(2)H_(4)conversion(98.22%).The sulfur electron bridge minimized the contact energy barrier between CuInS_(2)and CuS to enhance photogenerated carrier separation efficiency,while the asymmetric active sites in CuInS_(2)effectively reduced mutual repulsion of reaction intermediates.This work develops a hybrid catalytic system enabling synergistic regulation of reaction kinetics and thermodynamics,offering an innovative strategy for highly selective photocatalytic CO₂-to-C_(2)H_(4)production.展开更多
The structure, separation principle and feasibility research for a new type of vehicle air filter called the high speed rotary positive air filter were described. The analysis of the experimental data showed that the ...The structure, separation principle and feasibility research for a new type of vehicle air filter called the high speed rotary positive air filter were described. The analysis of the experimental data showed that the principle and structure of it were feasible and it possessed high separation efficiency and great self cleaning ability. Compared with the conventional air filter it also has lower air intake loss. So it is worth further practical research.展开更多
Under the background of increasingly scarce ore worldwide and increasingly fierce market competition,developing the mining industry could be strongly restricted.Intelligent ore sorting equipment not only improves ore ...Under the background of increasingly scarce ore worldwide and increasingly fierce market competition,developing the mining industry could be strongly restricted.Intelligent ore sorting equipment not only improves ore use and enhances the economic benefits of enterprises but also increases the ore grade and lessens the grinding cost and tailings production.However,long-term research on intelligent ore sorting equipment found that the factors affecting sorting efficiency mainly include ore information identification technology,equipment sorting actuator,and information processing algorithm.The high precision,strong anti-interference capability,and high speed of these factors guarantee the separation efficiency of intelligent ore sorting equipment.Color ore sorter,X-ray ore transmission sorter,dual-energy X-ray transmission ore sorter,X-ray fluorescence ore sorter,and near-infrared ore sorter have been successfully developed in accordance with the different characteristics of minerals while ensuring the accuracy of equipment sorting and improving the equipment sorting efficiency.With the continuous improvement of mine automation level,the application of online element rapid analysis technology with high speed,high precision,and strong anti-interference capability in intelligent ore sorting equipment will become an inevitable trend of equipment development in the future.Laser-induced breakdown spectroscopy,transientγneutron activation analysis,online Fourier transform infrared spectroscopy,and nuclear magnetic resonance techniques will promote the development of ore sorting equipment.In addition,the improvement and joint application of additional high-speed and high-precision operation algorithms(such as peak area,principal component analysis,artificial neural network,partial least squares,and Monte Carlo library least squares methods)are an essential part of the development of intelligent ore sorting equipment in the future.展开更多
The gas/liquid spiral separator, a key component in the compressed air system, was used to remove liquid and oil from gas stream by centrifugal and gravitational forces. To optimize the design of the separator,the rel...The gas/liquid spiral separator, a key component in the compressed air system, was used to remove liquid and oil from gas stream by centrifugal and gravitational forces. To optimize the design of the separator,the relationship between the performance and structural parameters of separators is studied. Computational fluid dynamics (CFD) method is employed to simulate the flow fields and calculate the pressure drop and separation efficiency of air-liquid spiral separators with different structural parameters. The RSM (Reynolds stress model)turbulence model is used to analyze the highly swirling flow fields while the stochastic trajectory model is used to simulate the traces of liquid droplets in the flow field. A simplified calculation formula of pressure drop in spiral structures is obtained by modifying Darcy's equation and verified by experiment.展开更多
The velocity profiles and separation efficiency curves of a hydrocyclone were predicted by an Euler-Euler approach using a computational fluid dynamics tool ANSYS-CFX 14.5. The Euler-Euler approach is capable of consi...The velocity profiles and separation efficiency curves of a hydrocyclone were predicted by an Euler-Euler approach using a computational fluid dynamics tool ANSYS-CFX 14.5. The Euler-Euler approach is capable of considering the particle-particle interactions and is appropriate for highly laden liquid-solid mixtures. Pre- dicted results were compared and validated with experi- mental results and showed a considerably good agreement. An increase in the particle cut size with increasing solid concentration of the inlet mixture flow was observed and discussed. In addition to this, the erosion on hydrocyclone walls constructed from stainless steel 410, eroded by sand particles （mainly SiOz）, was predicted with the Euler-La- grange approach. In this approach, the abrasive solid particles were traced in a Lagrangian reference frame as discrete particles. The increases in the input flow velocity, solid concentration, and the particle size have increased the erosion at the upper part of the cylindrical body of the hydrocyclone, where the tangential inlet flow enters the hydrocyclone. The erosion density in the area between the cylindrical to conical body area, in comparison to other parts of the hydrocyclone, also increased considerably. Moreover, it was observed that an increase in the particle shape factor from 0.1 to 1.0 leads to a decrease of almost 70 % in the average erosion density of the hydrocyclone wall surfaces.展开更多
Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation plants.As a...Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation plants.As a novel approach,this study implemented a conscious-lab "CL" for filling this gap.In this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time considered.These explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the unit.SHAP could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF circuit.XGBoost could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).展开更多
The cyclone separator is an important separation device.This paper presents a new type of embedded two-stage cyclone,which includes a 2 nd-stage cyclone(internal traditional cyclone)with multiple inlets and a 1 st-sta...The cyclone separator is an important separation device.This paper presents a new type of embedded two-stage cyclone,which includes a 2 nd-stage cyclone(internal traditional cyclone)with multiple inlets and a 1 st-stage cyclone(outer cylinder)that unifies the 2 nd-stage cyclone inlets into one inlet.The Taguchi experimental method was used to study the two-stage cyclone separator’s inlet area on its performance.Studies have shown that the increase of the 1 st-stage cyclone inlet area and the increase in the number of 2 nd-stage cyclone inlets(N)positively affect reducing the pressure drop and a negative effect on efficiency.It is recommended to use 2 S(the original 1 st-stage cyclone inlet area)of the 1 st-stage cyclone inlet area and 2 N of the 2 nd-stage cyclone inlets when separating fine particles.Compared with a traditional cyclone,the pressure drop is reduced by 1303 Pa,the mass separation efficiency(Eq)is increased by 0.56%,and the number separation efficiency(En)is increased by 2.05%.When separating larger particles,it is recommended to use 2 S of the 1 st-stage cyclone inlet area and 4 N of the 2 nd-stage cyclone inlets.Compared with a traditional cyclone,although Endecreases slightly,the pressure drop is reduced by 3055 Pa,and the Eqis increased by 0.56%.The research results provide new insight into the design of the cyclone.展开更多
In a passive ultra-high frequency(UHF)radio frequency identification(RFID)system,the recovery of collided tag signals on a physical layer can enhance identification efficiency.However,frequency drift is very common in...In a passive ultra-high frequency(UHF)radio frequency identification(RFID)system,the recovery of collided tag signals on a physical layer can enhance identification efficiency.However,frequency drift is very common in UHF RFID systems,and will have an influence on the recovery on the physical layer.To address the problem of recovery with the frequency drift,this paper adopts a radial basis function(RBF)network to separate the collision signals,and decode the signals via FM0 to recovery collided RFID tags.Numerical results show that the method in this paper has better performance of symbol error rate(SER)and separation efficiency compared to conventional methods when frequency drift occurs.展开更多
Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alt...Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alternative process that could be used for the beneficiation of ultra-fine material. This process has not been extensively used commercially because of its complex dependency on process parameters. In this paper, a selective flocculation process, using synthetic mixtures of hematite and kaolinite in different ratios, was attempted, and the ad-sorption mechanism was investigated by Fourier transform infrared （FTIR） spectroscopy. A three-layer artificial neural network （ANN） model （4？4？3） was used to predict the separation performance of the process in terms of grade, Fe recovery, and separation efficiency. The model values were in good agreement with experimental values.展开更多
Vortices motion in the anisotropic turbulent flow of cyclones makes a vital impact on flow stability and collection performance.Nevertheless,there remains a lack of clarity in the overall feature of vortices motion.In...Vortices motion in the anisotropic turbulent flow of cyclones makes a vital impact on flow stability and collection performance.Nevertheless,there remains a lack of clarity in the overall feature of vortices motion.In this work,a numerical analysis was conducted to clarify the complex motion of the vortex core in a cyclone separator.The validity of the numerical model was demonstrated by comparing the computational results with experimental data in the literature.As revealed by the results,the vortex core not only has a precession motion about the geometrical center axis but also does a nutation motion in the axial direction.The frequencies of the precession motions show two main peaks.And the magnitudes of the precession and nutation motions have non-uniform distributions in the cyclone.Moreover,the precession-nutation motions of the vortex cores exhibit a similar fluctuant pattern to the dust ring on the separator wall.The inlet gas velocity and the inlet solid loading show vital effects on the magnitudes and frequencies of precession and nutation motion.展开更多
Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from ...Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.展开更多
Catalytic cracking is the main method to lighten heavy crude oil,this process can produce high quality oil products such as gasoline and diesel,but also produces a large amount of fluid catalytic cracking slurry(FCCS)...Catalytic cracking is the main method to lighten heavy crude oil,this process can produce high quality oil products such as gasoline and diesel,but also produces a large amount of fluid catalytic cracking slurry(FCCS).The catalyst particles in FCCS seriously restrict the secondary processing of FCCS and need to be removed,and the properties of Fccs is an important factor that affects the removal efficiency of the catalyst particles.Based on the"effective contact point"model proposed by the research group,this study further proposed the"electrostatic separation efficiency calculation"model.In this model,since Fccs has a uniform distribution of catalyst particles,the ratio of the number of catalyst particles can be expressed as the ratio of area to achieve the calculation of separation efficiency.Then the catalyst removal efficiency under different viscosity was analyzed,thus verifying the feasibility of this model.The effects of temperature and mass ratio of four components on the viscosity of FccS were investigated respectively,then the effects of temperature and four components'mass ratio on the electrostatic sep-aration can be directly converted into the effect of viscosity on the electrostatic separation efficiency.All the results show the electrostatic separation efficiency decreases with increasing viscosity,and the best separationtemperatureis120℃.展开更多
We report a photoelectrochemical investigation of BiVO4 photoanodes prepared by successive ionic layer adsorption and reaction(SILAR),a facile method that yields uniform nanoporous films.After characterization of the ...We report a photoelectrochemical investigation of BiVO4 photoanodes prepared by successive ionic layer adsorption and reaction(SILAR),a facile method that yields uniform nanoporous films.After characterization of the phase,morphology,composition,and optical properties of the prepared films,the efficiencies of charge separation(ηsep)and water oxidation(ηox)in solar water splitting cells employing these photoanodes were estimated following a previously reported procedure.Unexpected wavelength and illumination direction dependencies were discovered in the derived efficiencies,casting doubt on the validity of the analysis.An alternative approach using a diffusion–reaction model that explicitly considers the efficiency of electron collection resolved the discrepancies and explained the illumination direction dependence of the photocurrent.Electron diffusion lengths(Ln)of 0.45μm and 0.55μm were derived for pristine and cobalt phosphate(Co-Pi)modified BiVO4,respectively,which are much shorter than the film thickness of^2.1μm.The Co-Pi treatment also increasedηoxfrom 0.86 to^1,which is the main reason for the overall performance enhancement caused by adding Co-Pi.These findings suggest that there is little scope for improving the performance of SILAR-deposited BiVO4 photoanodes by further catalyzing water oxidation,but enhanced performance is achievable if electron transport can be improved.展开更多
Three different inlets of hydrocyclone are studied in combination with the construction of a dowrahole system and hydrocyclone. By comparing the relationship between the inlet structure ＆ dimensional parameter of hyd...Three different inlets of hydrocyclone are studied in combination with the construction of a dowrahole system and hydrocyclone. By comparing the relationship between the inlet structure ＆ dimensional parameter of hydrocyclone and separation efficiency ＆ pressure loss, the highest efficiency is obtained from the inlet of an involute curve with increasing depth-width ratio from the three types, in which the separation efficiency and pressure loss all drops slowly, for the length of the channel decreases, while it drops rapidly in the other two. The flow guiding ability of the inlet affects the separation efficiency greatly, so the corresponding involute type of inlet of hydrocyclone fits for downhole oil-water separation is optimized, which serves as a basis for the structural design of downhole hydrocyclone.展开更多
To improve the efficiency of iron recovery from steel slag and reduce the wear-and-tear on facilities, a new method was proposed by adding a secondary screen sizer to the magnetic separation process according to grain...To improve the efficiency of iron recovery from steel slag and reduce the wear-and-tear on facilities, a new method was proposed by adding a secondary screen sizer to the magnetic separation process according to grain size distribution of magnetic iron （M-Fe） in the slag. The final recycling efficiency was evaluated by calculating the percentage of recycled M-Fe to the maximum amount of M-Fe that could be recovered. Three types of slags, namely basic oxygen furnace slag, desul- furization slag, and iron ladle slag, were studied, and the results showed that the optimized re- covery efficieneies were 93.20%, 92. 48%, and 85.82% respectively, and the recycling efficien eies were improved by 9.58%, 7.11%, and 6.24% respectively. Furthermore, the abrasion between the mill equipment and the remaining slags was significantly reduced owing to the efficient recovery of larger M-Fe particles. In addition, the using amount of grinding balls was reduced by 0. 46 kg when every 1 t steel slag was processed.展开更多
Coal is primarily beneficiated by wet gravity methods. The wet processing of coal is an efficient practice. However, it introduces the moisture in the range of 6%-15%, depending upon the size of coal which is as detri...Coal is primarily beneficiated by wet gravity methods. The wet processing of coal is an efficient practice. However, it introduces the moisture in the range of 6%-15%, depending upon the size of coal which is as detrimental as ash content to the heating value of coal. Dry beneficiation of coal fines was carried out using an air fluidized vibrating table in which the coal particles get separated from the heavier mineral particles as a result of horizontal and vertical stratification. Two level factorial design matrix was used to optimize and assess the interactive effects of the operational parameters of a pneumatic table viz. deck eccentric, side tilt and air flow rate on the clean coal yield and its ash content. Double stage processing was found to be more effective for reducing the ash content of the clean coal. Initial stage of processing at a higher ash level generates a reject of high ash with low combustibles. Cleaning of the rougher concentrate at 34%-35% ash level shows significant improvement in the organic efficiency （88.6%） and useful heat value of clean coal （15690 kJ/kg）. The performance of air fluidized vibrating deck was measured by Ep value which is 0.18.展开更多
文摘Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting because of its appropriate band structure,non-toxicity,high stability,and low cost.Nevertheless,its relatively low photochemical conversion efficiency limits its application,and enhancing its PEC water splitting efficiency remains a challenge.Consequently,increasing efforts have been rendered toward improving the performance of hematite photoanodes.The entire PEC water splitting efficiency typically includes three parts:the photon absorption efficiency,the separation efficiency of the semiconductor bulk,and the surface injection efficiency.This review briefly discusses the recent advances in studies on hematite photoanodes for water splitting,and through the enhancement of the three above-mentioned efficiencies,the corresponding strategies toward improving the PEC performance of hematite are comprehensively discussed and summarized.
文摘Sand production often leads to the failure of production equipment on offshore platform.Therefore,a new idea has been put forward,which is installing cyclone or baffle in the internal of the slug catcher for better sand control.In this paper,an experimental study is presented,which mainly includes sand particles accumulation shape,migration law and separation performance.The results suggest that the accumulation area is mainly divided into two zones:the crowded settlement zone and the free settlement zone.The crowded settlement zone has a special shape,which can be characterized by two parameters:accumulation length and accumulation angle.Axial sampling analysis shows obvious particle classification.Median particle size decreases with the increase of the axial distance,and the range of particle size distribution narrows gradually.The separation experiment shows that the gas velocity has the greatest influence on the separation efficiency.When the gas velocity is 14 m·s^ 1,the separation efficiency drops sharply,which can be abated by installing cyclone separator.In addition,the separation efficiency tends to be a constant under different gas velocities by installing baffle with appropriate height.Then the effectiveness and rationality of installing internal components can be strongly proved.All these provide important guidance for maximizing the sand control function of the slug catcher.
基金sponsored by the National Science Fund for Distinguished Young Scholars,China(22225804)the National Natural Science Foundation of China(22078102,22408101,22308105)。
文摘The limitations of swirl separation in removing microfine oil droplets in water have driven the development of hydrocyclone technology coupled with multiphase or multifield techniques.To enhance microfine oil droplets separation,a novel hydrocyclone separation coupled with fiber coalescence(HCCFC) was designed.The interaction between fiber balls and oil droplets inside the hydrocyclone,including droplet coalescence and breakage,was investigated.The influence of different operating parameters on separation efficiency was discussed.The results showed that fiber balls promoted oil droplet coalescence when the inlet droplet size(D_(43)) was below 22.37 μm but caused droplet breakage above this threshold.The coalescence performance of HCCFC improved with increasing inlet oil content but declined beyond 450 mg·L^(-1).Separation experiments confirmed that HCCFC outperformed conventional hydrocyclone,with separation efficiency increasing by 2.9% to 20.0%.As the fiber ball content and inlet flow rate increased,the separation efficiency showed a trend of first increasing and then decreasing.Additionally,HCCFC's separation efficiency varied with inlet oil droplet size distribution,showing the most significant enhancement when D_(43) was 22.37 μm,where separation efficiency increased by 14.4%.These findings offer insights into the development and application of multiphase coupled with hydrocyclone technology.
基金financial support by the National Natural Science Foundation of China(NSFC,Grant No.22379153 and 22109128)the Ningbo Key Research and Development Project(2023Z147)the Ningbo 3315 Program。
文摘CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.
文摘Photocatalytic reduction of CO_(2)into high-value C_(2)H_(4)offers a promising pathway toward carbon neutrality.Due to the continuous 12-electron-proton coupled reactions and the mutual repulsion of reaction intermediates,achieving highly selective photocatalytic conversion of CO_(2)to C_(2)H_(4)remains challenging.This work synthesized a CuInS_(2)/CuS heterojunction photocatalyst mediated by a sulfur electron bridge via a one-step solvothermal method,achieving a high selectivity for C_(2)H_(4)conversion(98.22%).The sulfur electron bridge minimized the contact energy barrier between CuInS_(2)and CuS to enhance photogenerated carrier separation efficiency,while the asymmetric active sites in CuInS_(2)effectively reduced mutual repulsion of reaction intermediates.This work develops a hybrid catalytic system enabling synergistic regulation of reaction kinetics and thermodynamics,offering an innovative strategy for highly selective photocatalytic CO₂-to-C_(2)H_(4)production.
文摘The structure, separation principle and feasibility research for a new type of vehicle air filter called the high speed rotary positive air filter were described. The analysis of the experimental data showed that the principle and structure of it were feasible and it possessed high separation efficiency and great self cleaning ability. Compared with the conventional air filter it also has lower air intake loss. So it is worth further practical research.
基金supported by the National Science and Technology Support Program of China(No.2012BAC11B07)the Jiangxi Science and Technology Innovation Base Plan(No.20212BCD42017)。
文摘Under the background of increasingly scarce ore worldwide and increasingly fierce market competition,developing the mining industry could be strongly restricted.Intelligent ore sorting equipment not only improves ore use and enhances the economic benefits of enterprises but also increases the ore grade and lessens the grinding cost and tailings production.However,long-term research on intelligent ore sorting equipment found that the factors affecting sorting efficiency mainly include ore information identification technology,equipment sorting actuator,and information processing algorithm.The high precision,strong anti-interference capability,and high speed of these factors guarantee the separation efficiency of intelligent ore sorting equipment.Color ore sorter,X-ray ore transmission sorter,dual-energy X-ray transmission ore sorter,X-ray fluorescence ore sorter,and near-infrared ore sorter have been successfully developed in accordance with the different characteristics of minerals while ensuring the accuracy of equipment sorting and improving the equipment sorting efficiency.With the continuous improvement of mine automation level,the application of online element rapid analysis technology with high speed,high precision,and strong anti-interference capability in intelligent ore sorting equipment will become an inevitable trend of equipment development in the future.Laser-induced breakdown spectroscopy,transientγneutron activation analysis,online Fourier transform infrared spectroscopy,and nuclear magnetic resonance techniques will promote the development of ore sorting equipment.In addition,the improvement and joint application of additional high-speed and high-precision operation algorithms(such as peak area,principal component analysis,artificial neural network,partial least squares,and Monte Carlo library least squares methods)are an essential part of the development of intelligent ore sorting equipment in the future.
文摘The gas/liquid spiral separator, a key component in the compressed air system, was used to remove liquid and oil from gas stream by centrifugal and gravitational forces. To optimize the design of the separator,the relationship between the performance and structural parameters of separators is studied. Computational fluid dynamics (CFD) method is employed to simulate the flow fields and calculate the pressure drop and separation efficiency of air-liquid spiral separators with different structural parameters. The RSM (Reynolds stress model)turbulence model is used to analyze the highly swirling flow fields while the stochastic trajectory model is used to simulate the traces of liquid droplets in the flow field. A simplified calculation formula of pressure drop in spiral structures is obtained by modifying Darcy's equation and verified by experiment.
基金“Stiftung Rheinland-Pfalz fur Innovation,Mainz,Germany,”for financial support
文摘The velocity profiles and separation efficiency curves of a hydrocyclone were predicted by an Euler-Euler approach using a computational fluid dynamics tool ANSYS-CFX 14.5. The Euler-Euler approach is capable of considering the particle-particle interactions and is appropriate for highly laden liquid-solid mixtures. Pre- dicted results were compared and validated with experi- mental results and showed a considerably good agreement. An increase in the particle cut size with increasing solid concentration of the inlet mixture flow was observed and discussed. In addition to this, the erosion on hydrocyclone walls constructed from stainless steel 410, eroded by sand particles （mainly SiOz）, was predicted with the Euler-La- grange approach. In this approach, the abrasive solid particles were traced in a Lagrangian reference frame as discrete particles. The increases in the input flow velocity, solid concentration, and the particle size have increased the erosion at the upper part of the cylindrical body of the hydrocyclone, where the tangential inlet flow enters the hydrocyclone. The erosion density in the area between the cylindrical to conical body area, in comparison to other parts of the hydrocyclone, also increased considerably. Moreover, it was observed that an increase in the particle shape factor from 0.1 to 1.0 leads to a decrease of almost 70 % in the average erosion density of the hydrocyclone wall surfaces.
文摘Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation plants.As a novel approach,this study implemented a conscious-lab "CL" for filling this gap.In this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time considered.These explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the unit.SHAP could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF circuit.XGBoost could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).
基金financially supported by the National Key Research and Development Program of China(2016YFC0801700)the Project of the National Natural Science Foundation of China(51604018)the Basic Research Funding of the China Academy of Safety Science and Technology(2019JBKY11 and 2019JBKY04)。
文摘The cyclone separator is an important separation device.This paper presents a new type of embedded two-stage cyclone,which includes a 2 nd-stage cyclone(internal traditional cyclone)with multiple inlets and a 1 st-stage cyclone(outer cylinder)that unifies the 2 nd-stage cyclone inlets into one inlet.The Taguchi experimental method was used to study the two-stage cyclone separator’s inlet area on its performance.Studies have shown that the increase of the 1 st-stage cyclone inlet area and the increase in the number of 2 nd-stage cyclone inlets(N)positively affect reducing the pressure drop and a negative effect on efficiency.It is recommended to use 2 S(the original 1 st-stage cyclone inlet area)of the 1 st-stage cyclone inlet area and 2 N of the 2 nd-stage cyclone inlets when separating fine particles.Compared with a traditional cyclone,the pressure drop is reduced by 1303 Pa,the mass separation efficiency(Eq)is increased by 0.56%,and the number separation efficiency(En)is increased by 2.05%.When separating larger particles,it is recommended to use 2 S of the 1 st-stage cyclone inlet area and 4 N of the 2 nd-stage cyclone inlets.Compared with a traditional cyclone,although Endecreases slightly,the pressure drop is reduced by 3055 Pa,and the Eqis increased by 0.56%.The research results provide new insight into the design of the cyclone.
基金supported by the National Natural Science Foundation of China(61762093)the 17th Batches of Young and Middle-aged Leaders in Academic and Technical Reserved Talents Project of Yunnan Province(2014HB019)+1 种基金the Key Applied and Basic Research Foundation of Yunnan Province(2018FA036)the Program for Innovative Research Team(in Science and Technology)in University of Yunnan Province。
文摘In a passive ultra-high frequency(UHF)radio frequency identification(RFID)system,the recovery of collided tag signals on a physical layer can enhance identification efficiency.However,frequency drift is very common in UHF RFID systems,and will have an influence on the recovery on the physical layer.To address the problem of recovery with the frequency drift,this paper adopts a radial basis function(RBF)network to separate the collision signals,and decode the signals via FM0 to recovery collided RFID tags.Numerical results show that the method in this paper has better performance of symbol error rate(SER)and separation efficiency compared to conventional methods when frequency drift occurs.
基金the funding given by Council of Scientific and Industrial Research(CSIR)India through project NWP-31 for this project
文摘Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alternative process that could be used for the beneficiation of ultra-fine material. This process has not been extensively used commercially because of its complex dependency on process parameters. In this paper, a selective flocculation process, using synthetic mixtures of hematite and kaolinite in different ratios, was attempted, and the ad-sorption mechanism was investigated by Fourier transform infrared （FTIR） spectroscopy. A three-layer artificial neural network （ANN） model （4？4？3） was used to predict the separation performance of the process in terms of grade, Fe recovery, and separation efficiency. The model values were in good agreement with experimental values.
基金Authors thank for the joint funding of a Key Research and Development Plan of Shandong Province(Public Science and Technology)(2019GSF109038)the Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province(2019MFRSE-A01)the National Natural Science Foundation of China(51809236).
文摘Vortices motion in the anisotropic turbulent flow of cyclones makes a vital impact on flow stability and collection performance.Nevertheless,there remains a lack of clarity in the overall feature of vortices motion.In this work,a numerical analysis was conducted to clarify the complex motion of the vortex core in a cyclone separator.The validity of the numerical model was demonstrated by comparing the computational results with experimental data in the literature.As revealed by the results,the vortex core not only has a precession motion about the geometrical center axis but also does a nutation motion in the axial direction.The frequencies of the precession motions show two main peaks.And the magnitudes of the precession and nutation motions have non-uniform distributions in the cyclone.Moreover,the precession-nutation motions of the vortex cores exhibit a similar fluctuant pattern to the dust ring on the separator wall.The inlet gas velocity and the inlet solid loading show vital effects on the magnitudes and frequencies of precession and nutation motion.
基金supported by the National Natural Science Foundation of China(51572253,21771171)Scientific Research Grant of Hefei National Synchrotron Radiation Laboratory(UN2017LHJJ)+1 种基金the Fundamental Research Funds for the Central Universitiescooperation between NSFC and Netherlands Organization for Scientific Research(51561135011)~~
文摘Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.
基金supported by the[Natural Science Foundation Project of Shandong Province#1]under Grant[ZR2019MEE033][Fundamental Research Funds for the central Universities#2]under Grant[19CX02035A].
文摘Catalytic cracking is the main method to lighten heavy crude oil,this process can produce high quality oil products such as gasoline and diesel,but also produces a large amount of fluid catalytic cracking slurry(FCCS).The catalyst particles in FCCS seriously restrict the secondary processing of FCCS and need to be removed,and the properties of Fccs is an important factor that affects the removal efficiency of the catalyst particles.Based on the"effective contact point"model proposed by the research group,this study further proposed the"electrostatic separation efficiency calculation"model.In this model,since Fccs has a uniform distribution of catalyst particles,the ratio of the number of catalyst particles can be expressed as the ratio of area to achieve the calculation of separation efficiency.Then the catalyst removal efficiency under different viscosity was analyzed,thus verifying the feasibility of this model.The effects of temperature and mass ratio of four components on the viscosity of FccS were investigated respectively,then the effects of temperature and four components'mass ratio on the electrostatic sep-aration can be directly converted into the effect of viscosity on the electrostatic separation efficiency.All the results show the electrostatic separation efficiency decreases with increasing viscosity,and the best separationtemperatureis120℃.
基金Universiti Brunei Darussalam through grant numbers UBD/RSCH/1.4/FICBF(b)/2018/009 and UBD/PNC2/2/RG/1(313).
文摘We report a photoelectrochemical investigation of BiVO4 photoanodes prepared by successive ionic layer adsorption and reaction(SILAR),a facile method that yields uniform nanoporous films.After characterization of the phase,morphology,composition,and optical properties of the prepared films,the efficiencies of charge separation(ηsep)and water oxidation(ηox)in solar water splitting cells employing these photoanodes were estimated following a previously reported procedure.Unexpected wavelength and illumination direction dependencies were discovered in the derived efficiencies,casting doubt on the validity of the analysis.An alternative approach using a diffusion–reaction model that explicitly considers the efficiency of electron collection resolved the discrepancies and explained the illumination direction dependence of the photocurrent.Electron diffusion lengths(Ln)of 0.45μm and 0.55μm were derived for pristine and cobalt phosphate(Co-Pi)modified BiVO4,respectively,which are much shorter than the film thickness of^2.1μm.The Co-Pi treatment also increasedηoxfrom 0.86 to^1,which is the main reason for the overall performance enhancement caused by adding Co-Pi.These findings suggest that there is little scope for improving the performance of SILAR-deposited BiVO4 photoanodes by further catalyzing water oxidation,but enhanced performance is achievable if electron transport can be improved.
文摘Three different inlets of hydrocyclone are studied in combination with the construction of a dowrahole system and hydrocyclone. By comparing the relationship between the inlet structure ＆ dimensional parameter of hydrocyclone and separation efficiency ＆ pressure loss, the highest efficiency is obtained from the inlet of an involute curve with increasing depth-width ratio from the three types, in which the separation efficiency and pressure loss all drops slowly, for the length of the channel decreases, while it drops rapidly in the other two. The flow guiding ability of the inlet affects the separation efficiency greatly, so the corresponding involute type of inlet of hydrocyclone fits for downhole oil-water separation is optimized, which serves as a basis for the structural design of downhole hydrocyclone.
基金the funding of Chongqing Application and Development Project of China(cstc2014yykfB100007)
文摘To improve the efficiency of iron recovery from steel slag and reduce the wear-and-tear on facilities, a new method was proposed by adding a secondary screen sizer to the magnetic separation process according to grain size distribution of magnetic iron （M-Fe） in the slag. The final recycling efficiency was evaluated by calculating the percentage of recycled M-Fe to the maximum amount of M-Fe that could be recovered. Three types of slags, namely basic oxygen furnace slag, desul- furization slag, and iron ladle slag, were studied, and the results showed that the optimized re- covery efficieneies were 93.20%, 92. 48%, and 85.82% respectively, and the recycling efficien eies were improved by 9.58%, 7.11%, and 6.24% respectively. Furthermore, the abrasion between the mill equipment and the remaining slags was significantly reduced owing to the efficient recovery of larger M-Fe particles. In addition, the using amount of grinding balls was reduced by 0. 46 kg when every 1 t steel slag was processed.
文摘Coal is primarily beneficiated by wet gravity methods. The wet processing of coal is an efficient practice. However, it introduces the moisture in the range of 6%-15%, depending upon the size of coal which is as detrimental as ash content to the heating value of coal. Dry beneficiation of coal fines was carried out using an air fluidized vibrating table in which the coal particles get separated from the heavier mineral particles as a result of horizontal and vertical stratification. Two level factorial design matrix was used to optimize and assess the interactive effects of the operational parameters of a pneumatic table viz. deck eccentric, side tilt and air flow rate on the clean coal yield and its ash content. Double stage processing was found to be more effective for reducing the ash content of the clean coal. Initial stage of processing at a higher ash level generates a reject of high ash with low combustibles. Cleaning of the rougher concentrate at 34%-35% ash level shows significant improvement in the organic efficiency （88.6%） and useful heat value of clean coal （15690 kJ/kg）. The performance of air fluidized vibrating deck was measured by Ep value which is 0.18.
