The spout-fluidizing characteristics of high-carbon ferromanganese powders with different sizes and masses were studied via a plexiglass spout-fluidized bed with an inner diameter of 30 mm and a height of 1000 mm.The ...The spout-fluidizing characteristics of high-carbon ferromanganese powders with different sizes and masses were studied via a plexiglass spout-fluidized bed with an inner diameter of 30 mm and a height of 1000 mm.The relationships between bed voidage and such parameters as bed height,particle size,fluidizing air velocity,and air flow were obtained.Experimental results show that the powder material with high density can be fluidized in the spout-fluidized bed where the particle size is a key factor influencing the quality of fluidization.展开更多
Dual fluidized bed gasifiers （DFBG） are effective in producing nitrogen-free syngas from biomass. How- ever, to improve the gasifier performance, pressure drops and solid fractions within the DFBG system need to be ...Dual fluidized bed gasifiers （DFBG） are effective in producing nitrogen-free syngas from biomass. How- ever, to improve the gasifier performance, pressure drops and solid fractions within the DFBG system need to be controlled. In this study, the effects of varying the fluidizing velocity in the fast fluidized bed （FFB） on the pressure drops and the solid fractions in the system were investigated in a 100 kW DFBG and in a dual fluidized bed cold model （DFCM）. Based on the experimental results, empirical correlations were developed to predict the height-averaged solid fraction in the bottom section of the FFB. Accuracy and advantages of the correlations were analyzed. The correlation is useful for design and modeling of the DFBG systems where the height-averaged solid fraction is required to be determined.展开更多
As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-s...As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-sulfur bauxite were simulated using the computational particle fluid dynamics(CPFD) method.The effect of primary air flow velocity on particle velocity,particle volume distribution,furnace temperature distribution and pressure distribution were investigated.Under the condition of the same total flow of natural gas,the impact of the number of inlets on the desulfurization efficiency,atmosphere mass fraction distribution and temperature distribution in the furnace was further investigated.展开更多
Nickel laterite ore is an important nickel-bearing mineral.Research on pre-heating and hydrogen pre-reduction in the pyrometallurgical process of nickel laterite ore is very limited,especially when using fluidized bed...Nickel laterite ore is an important nickel-bearing mineral.Research on pre-heating and hydrogen pre-reduction in the pyrometallurgical process of nickel laterite ore is very limited,especially when using fluidized bed roasting.This study systematically explores the mechanisms of fluidized bed pre-heating treatment and hydrogen pre-reduction in the roasting process of saprolitic nickel laterite ore.According to single-factor experiment results,the appropriate pre-heating and pre-reduction conditions were a pre-heating temperature of 700℃,a pre-heating time of 30 min,a pre-reduction temperature of 700℃,a pre-reduction time of 30 min,and a hydrogen concentration of 80%.Then,the nickel metallization rate and iron metallization rate reached 90.56%and 41.31%,respectively.Various analytical and testing methods were employed to study the changes in phase composition,magnetism,surface element valence states,and microstructure of nickel laterite ore during fluidized pre-heating and pre-reduction.The study shows that hydrogen can achieve nickel reduction at relatively low temperatures.It was also found that pre-heating treatment of nickel laterite ore is beneficial.Pre-heating opens up the mineral structures of serpentine and limonite,allowing the reducing gas and nickel to interact quickly during the reduction process,enhancing the pre-reduction process.展开更多
By large-scale cold mold experiments,pressure pulsation signals within the jet influence zone of riser reactor are processed by using Hilbert-Huang analysis(HHT)in this study.Effects of different jet forms and operati...By large-scale cold mold experiments,pressure pulsation signals within the jet influence zone of riser reactor are processed by using Hilbert-Huang analysis(HHT)in this study.Effects of different jet forms and operating conditions on the intrinsic mode function(IMF)energy and Hilbert-Huang spectrum are compared.Results show that the IMF energy and Hilbert-Huang spectrum of pressure pulsation signals show significant differences under the influence of upward and downward jets.Moreover,the change of jet velocity will also lead to significant changes in IMF energy and Hilbert-Huang spectrum.Among them,energy values and energy proportions corresponding to high-frequency pressure pulsations show a good correlation with the jet velocity.On this basis,energy value and energy proportion data in the high frequency range of the original pressure signal are clustered and analyzed by using the K-means clustering algorithm.Based on clustering results,the jet influence zone of riser can be defined into three regions.From partitioning results,it is found that the introduction of downward inclined jets could effectively improve the gas-solid mixing in the feed injection zone of riser.展开更多
Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is...Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is approximated by the Gaussian distribution and added to experimental capacitance data with various intensities.The equivalent signal strength(Ф)that equals the signal-to-noise ratio of packed beds is used to evaluate noise levels.Results show that the Pearson correlation coefficient,which indicates the similarity of solids fraction distributions over pixels,increases with Ф,and reconstructed images are more deteriorated at lower Ф.Nevertheless,relative errors for average solids fraction and bubble size in each frame are less sensitive to noise,attributed to noise compromise caused by the process of pixel values.These findings provide useful guidance for assessing the accuracy of ECT measurements of multiphase flows.展开更多
A feasible criterion was established to determine the lower size limit of raw coal(d_(pRm))for efficient beneficiation in the air-fluidized bed with magnetite particles.The feasibility of using small magnetite particl...A feasible criterion was established to determine the lower size limit of raw coal(d_(pRm))for efficient beneficiation in the air-fluidized bed with magnetite particles.The feasibility of using small magnetite particles to accommodate the fine raw coal was demonstrated from the experimental perspective.The minimum size for the magnetite particles to be fluidized smoothly was clarified as 47.1μm,which corresponded to the border between Geldart-B and-A groups.Since the gangue and coal components in the raw coal were crushed into the same size,d_(pRm)depended on the greater one between d_(pGm)(minimum size required for the gangue particles to sink towards the bottom)and d_(pCm)(minimum size required for the coal particles to float towards the top).dpcm was determined as 259μm by supposing that provided the gangue particles accumulated in the lower half bed,they could be potentially extracted from the bottom.On the other hand,it was observed that the coal particles could always accumulate in the upper half bed.Under such circumstances,dpcm was revealed as 9.8μm since finer coal particles would be blown out by air before the 47.1μm sized magnetite particles became fluidized.Eventually,dpRm was clarified as 259μm,agreeing with the common view that raw coal coarser than 6 mm could be effectively beneficiated in the air-fluidized bed with magnetite particles.Additionally,the difficulty in beneficiating the fine raw coal was revealed to arise more from the remixing of sorted gangue particles than that of separated coal particles.展开更多
With the intelligent transformation of process manufacturing,accurate and comprehensive perception information is fundamental for application of artificial intelligence methods.In zinc smelting,the fluidized bed roast...With the intelligent transformation of process manufacturing,accurate and comprehensive perception information is fundamental for application of artificial intelligence methods.In zinc smelting,the fluidized bed roaster is a key piece of large-scale equipment and plays a critical role in the manufacturing industry;its internal temperature field directly determines the quality of zinc calcine and other related products.However,due to its vast spatial dimensions,the limited observation methods,and the complex multiphase,multifield coupled reaction atmosphere inside it,accurately and timely perceiving its temperature field remains a significant challenge.To address these challenges,a spatial-temporal reduced-order model(STROM)is proposed,which can realize fast and accurate temperature field perception based on sparse observation data.Specifically,to address the difficulty in matching the initial physical field with the sparse observation data,an initial field construction based on data assimilation(IFCDA)method is proposed to ensure that the initial conditions of the model can be matched with the actual operation state,which provides a basis for constructing a high-precision computational fluid dynamics(CFD)model.Then,to address the high simulation cost of high-precision CFD models under full working conditions,a high uniformity(HU)-orthogonal test design(OTD)method with the centered L2 deviation is innovatively proposed to ensure high information coverage of the temperature field dataset under typical working conditions in terms of multiple factors and levels of the component,feed,and blast parameters.Finally,to address the difficulty in real-time and accurate temperature field prediction,considering the spatial correlation between the observed temperature and the temperature field,as well as the dynamic correlation of the observed temperature in the time dimension,a spatial-temporal predictive model(STPM)is established,which realizes rapid prediction of the temperature field through sparse observa-tion data.To verify the accuracy and validity of the proposed method,CFD model validation and reduced-order model prediction experiments are designed,and the results show that the proposed method can realize high-precision and fast prediction of the roaster temperature field under different working conditions through sparse observation data.Compared with the CFD model,the prediction root-mean-square error(RMSE)of STROM is less than 0.038,and the computational efficiency is improved by 3.4184×10^(4)times.In particular,STROM also has a good prediction ability for unmodeled conditions,with a prediction RMSE of less than 0.1089.展开更多
The aim of this study was to develop a novel pharmaceutical excipient:an anion exchange resin.Initially,polystyrenedivinylbenzene(PS-DVB)microspheres were synthesized via suspension polymerization.Subsequently,these m...The aim of this study was to develop a novel pharmaceutical excipient:an anion exchange resin.Initially,polystyrenedivinylbenzene(PS-DVB)microspheres were synthesized via suspension polymerization.Subsequently,these microspheres served as a substrate for chloromethylation using methanol,formaldehyde,and chlorosulfonic acid.By optimizing the reaction conditions,the chloromethylated microspheres were characterized using infrared spectroscopy,scanning electron microscopy,and the Mohr method.Under optimal reaction conditions,the resulting products exhibited uniformity and spherical morphology,with an average particle size of approximately 190μm.The PS-DVB microspheres effectively incorporated chloromethyl groups,as evidenced by a chlorine content of 14.67%.Scanning electron microscopy analysis indicated that the appearance of the microspheres remained largely unchanged post-reaction.Overall,the research findings demonstrated the successful preparation of the anion exchange resin.Characterization and quality assessment confirmed that the ion exchange resin met the required standards.展开更多
Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really unifor...Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really uniform films.This work combining nanoparticle fluidization technology with atomic layer deposition(ALD) technology to achieve precise surface modification of a large number of micro-nano particles.First,we explored the fluidization characteristics of TiO_(2) nanoparticles in a home-made atmospheric fluidized bed ALD reactor(FB-ALD) to ensure the uniform fluidization of a large number of nanoparticles.Then TiCl_(4) and H_(2)O were used as precursors to deposit amorphous TiO_(2) films on the surface of TiO_(2) nanoparticles at 80℃ under atmospheric pressure,and the growth per cycle was about 0.109 nm per cycle.After 30 ALD cycles,the film thickness was about 3.1 nm,which could almost fully suppress the photocatalytic activity of TiO_(2).Compared with other traditional coating materials,amorphous TiO_(2) has higher light refractive index,and realizes the suppression of the photocatalytic activity of TiO_(2) without introducing other substances,demonstrating greater application potential in TiO_(2) pigment coating field.The process is a gas-phase coating method,which is efficient,no waste water,and easy to scale up.This work shown the excellent property of interface engineering in improving pigment weatherability and can also provide guidance for the nanoparticle surface modification.展开更多
The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this...The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this study proposes an innovative hybrid approach that integrates wavelet neural network(WNN)with chaos analysis.By leveraging the Cross-Correlation(C−C)method,the minimum embedding dimension for phase space reconstruction is systematically calculated and then adopted as the input node configuration for the WNN.Simulation results demonstrate the remarkable effectiveness of this integrated method in predicting pressure drop signals,advancing our understanding of the intricate dynamic phenomena occurring with V−L−S fluidized bed evaporators.Moreover,this study offers a novel perspective on applying advanced data-driven techniques to handle the complexities of multi-phase flow systems and highlights the potential for improved operational prediction and control in industrial settings.展开更多
Pressurized oxy-fuel combustion is a next-generation and low-cost carbon capture technology with industrial application potential.This work presents an innovative research exploration-coupling coal pressurized fluidiz...Pressurized oxy-fuel combustion is a next-generation and low-cost carbon capture technology with industrial application potential.This work presents an innovative research exploration-coupling coal pressurized fluidized bed oxy-fuel combustion technology with energy utilization of poultry manure as a renewable and carbon-neutral fuel,in order to capture CO_(2)and solve the problem of poultry manure treatment simultaneously.In this study,a stable co-combustion of coal and chicken manure in a laboratory-scale pressurized fluidized bed under typical oxy-fuel condition(30%O_(2)/70%CO_(2),i.e.,Oxy-30)is achieved.The key parameters including the combustion pressure(0.1-0.5 MPa)and chicken-manure proportion(0%to 100%)and their impacts on fundamental combustion efficiency,carbon conversion,nitrogen and sulfur pollutant emissions,and residue ash characteristics have been investigated.The result show that pressurization favors an increase in the CO_(2)enrichment concentration and fluidized bed combustion efficiency.During co-combustion under 0.1 and 0.3 MPa,the CO_(2)concentration in the flue gas is the highest when the chicken manure blending ratio(M_(pm))is 25%.Although the NO emissions fluctuate and even increase as Mpm increases,the co-combustion of coal and chicken manure exhibits a synergistic effect in reducing NO conversion rate(XNO).The effect of pressurization on reducing NO emission is significant,XNO at M_(pm)=25%decreasing from 15%to 5%as the pressure(P)increases from 0.1 to 0.5 MPa.As P increases from 0.1 to 0.5 MPa and Mpm increases from 0%to 50%,the SO_(2) emissions and conversion rates decrease.The self-desulfurization process plays an important role in the reduction of SO_(2) emissions during pressurized oxy-fuel co-combustion.The aim of this work is to advance the development and application of pressurized fluidized bed oxy-fuel co-combustion technology and promote a circular bioeconomy and carbon-free waste management for biomass derived from livestock manure.展开更多
For the treatment of the mixed flue gas desulfurization wastewater with high salinity by the biological fluidized bed process,the optimum temperature was 25-35℃,and the optimum hydraulic retention time was 10 h.When ...For the treatment of the mixed flue gas desulfurization wastewater with high salinity by the biological fluidized bed process,the optimum temperature was 25-35℃,and the optimum hydraulic retention time was 10 h.When the influent quality was stable,the average concentration of COD,NH_(4)^(+)-N and TN in the inlet water was 210,11 and 16.3 mg/L,respectively,and their average concentration in the effluent was 54,0.32 and 4.09 mg/L,respectively.The treatment effect was good.When the incoming water quality of flue gas desulfurization wastewater fluctuated greatly,the effluent quality was still relatively stable after being treated by the biological fluidized bed,indicating that the biological fluidized bed process had a good ability to resist the impact of water quality in the treatment of high-salinity flue gas desulfurization wastewater.At the same time,the biological fluidized bed process provides a reference for high-salinity wastewater that is difficult to be biologically treated.展开更多
Fluidized solidified soil(FSS)is an innovative backfill material that offers benefits such as easy pumping and straightforward construction.This study examined how varying the water-soil ratio and the curing agent dos...Fluidized solidified soil(FSS)is an innovative backfill material that offers benefits such as easy pumping and straightforward construction.This study examined how varying the water-soil ratio and the curing agent dosage affect the properties and microstructure of FSS.The strength development mechanism was investigated when composite solidification agents were used.The findings show that both the water-solid ratio and the curing agent dosage can affect the microstructure of FSS,thereby affecting its performance.When the water-solid ratio increases from 0.52 to 0.56,the unconfined compressive strength(UCS)and flexural strength of the FSS decrease by 34.1% and 39.3% after 28 d.Conversely,the curing agent dosage increasing from 10% to 30% will increase both UCS and flexural strength by 11.2 times and 11.1 times.As the curing age increases,the number of cracks at failure point in the FSS will increase and lead to a more complete failure.Numerous needle-like AFt,C-S-H gel,and C-(A)-S-H gel create a three-dimensional network by adhering to soil particles.展开更多
A novel inverted advanced treatment process of ozone/hydrogen peroxide(O_(3)/H_(2)O_(2))and biological activated carbon fluidized bed(BACFB)before the conventional process has been developed to treat the high-algae-la...A novel inverted advanced treatment process of ozone/hydrogen peroxide(O_(3)/H_(2)O_(2))and biological activated carbon fluidized bed(BACFB)before the conventional process has been developed to treat the high-algae-laden reservoir water,which aims to enhance the removal of dissolved organic matter(DOM),odorants as well as the precursors of disinfection by-products(DBPs).Before and after the renovation,the average value of chemical oxygen demand(determined by potassium permanganate method)in the filter effluent decreased from 2.18 to 1.15 mg/L.Likewise,the average concentrations of turbidity dropped from 0.640 to 0.098 NTU,indicating substantial improvement following the renovation.Formation potential of DBPs such as trihalomethanes and haloacetic acids were also reduced greatly.The results of the polarity rapid analysis method indicated that ozonation primarily removed non-polar and positively charged organic matter,while coagulation-sedimentation targeted non-positive organic matter.The results of fluorescence spectroscopy and highresolution mass spectrometry indicated that the new process effectively removed DOM,and decreased the number of nitrogen-containing compounds.Additionally,the inverted O_(3)/H_(2)O_(2) and BACFB process promoted the dynamic transformation between DOM components and significantly reduced overall aromatic content.This study provided a promising solution for treating high-algae-laden source water and verified the feasibility and effectiveness of this novel process in practice.展开更多
To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic r...To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic ratio （molar ratio of Na2O to Al2O3 in the sodium aluminate solution） of 25, a molar ratio of CaO to SiO2 in the fly ash of 1.1, a liquid volume to solid mass ratio of 9, a reaction temperature of 280 ℃, and a residence time of 1 h when treating fly ash with an alumina to silica mass ratio （A/S） of 0.78 and an alumina content of 32.43%. Additionally, the alumina leaching mechanism was explored via structural and chemical analysis, which revealed that after alkaline digestion, the main solid phase containing silica was NaCaHSiO4 with a theoretical A/S of zero.展开更多
Natural rutile and gaseous chlorine with carbon as reductant were used to prepare titanium tetrachloride. Thermodynamics and kinetics of chlorination of Kenya natural rutile particles in a batch-type fluidized bed wer...Natural rutile and gaseous chlorine with carbon as reductant were used to prepare titanium tetrachloride. Thermodynamics and kinetics of chlorination of Kenya natural rutile particles in a batch-type fluidized bed were studied at 1173-1273 K. Thermodynamic analysis of this system revealed that the equation of producing CO was dominant at high temperatures. Based on the gas-solid multi-phase reaction theory and a two-phase model for the fluidized bed, the mathematical description for the chlorination reaction of rutile was proposed. The reaction parameters and the average concentration of gaseous chlorine in the emulsion phase were estimated. The average concentration of emulsion phase in the range of fluidized bed was calculated as 0.3 mol/m^3. The results showed that the chlorination of natural rutile proceeded principally in the emulsion phase, and the reaction rate was mainly controlled by the surface reaction.展开更多
The pressurized combustion experiments of bituminous coal and lignite under air and O2/CO2 atmospheres were conducted to study the influences of pressure and atmosphere on combustion and the CO, NO, SO2 release proces...The pressurized combustion experiments of bituminous coal and lignite under air and O2/CO2 atmospheres were conducted to study the influences of pressure and atmosphere on combustion and the CO, NO, SO2 release process. Two indices, the maximum concentration and the total emission, were applied to quantitatively evaluate the influence of several different operating parameters such as pressure, atmosphere and temperature on the formation of NO and SO2 during coal combustion in the fluidized bed. The experimental results show that the releasing profiles of CO, NO and SO2 during coal combustion under a pressurized oxy- fuel atmosphere are similar to those under a pressurized air atmosphere, and the curves of measured gas components are all unimodal. Under the oxy-fuel condition, pressure increasing from 0.1 to 0.7 MPa can cause the inhibition of NO and SO2 emission. The elevation of temperature can lead to an increase in the maximum concentration and the total production of NO and SO2, and the increase under atmospheric pressure is higher than that under high pressure.展开更多
In order to solve the agglomeration problem in TiCl4 preparation,a new test in a multistage series combined fluidized bed was studied on a pilot scale.The pilot plant can make full use of titanium slag with a high con...In order to solve the agglomeration problem in TiCl4 preparation,a new test in a multistage series combined fluidized bed was studied on a pilot scale.The pilot plant can make full use of titanium slag with a high content of MgO and CaO as the feedstock.Several experimental parameters such as chlorine flow and reaction temperature were discussed and the morphology and components of reaction product were analyzed.According to the results,the conversion rate of TiO2 is up to 90%.It is found that the combined fluidized bed has good anti-agglomeration ability because the accumulation of MgCl2 and CaCl2 on the surface of unreacted slag was carried out of the reactor.展开更多
基金sponsored by National Natural Science Foundation of China and Baosteel Group Corporation (No.50974149)
文摘The spout-fluidizing characteristics of high-carbon ferromanganese powders with different sizes and masses were studied via a plexiglass spout-fluidized bed with an inner diameter of 30 mm and a height of 1000 mm.The relationships between bed voidage and such parameters as bed height,particle size,fluidizing air velocity,and air flow were obtained.Experimental results show that the powder material with high density can be fluidized in the spout-fluidized bed where the particle size is a key factor influencing the quality of fluidization.
基金funded by the Ministry of Business,Innovation and Employment,New Zealand
文摘Dual fluidized bed gasifiers （DFBG） are effective in producing nitrogen-free syngas from biomass. How- ever, to improve the gasifier performance, pressure drops and solid fractions within the DFBG system need to be controlled. In this study, the effects of varying the fluidizing velocity in the fast fluidized bed （FFB） on the pressure drops and the solid fractions in the system were investigated in a 100 kW DFBG and in a dual fluidized bed cold model （DFCM）. Based on the experimental results, empirical correlations were developed to predict the height-averaged solid fraction in the bottom section of the FFB. Accuracy and advantages of the correlations were analyzed. The correlation is useful for design and modeling of the DFBG systems where the height-averaged solid fraction is required to be determined.
基金supported by the National Key Research and Development Program of China(2022YFC2904400)Guangxi Science and Technology Major Project(Gui Ke AA23023033)。
文摘As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-sulfur bauxite were simulated using the computational particle fluid dynamics(CPFD) method.The effect of primary air flow velocity on particle velocity,particle volume distribution,furnace temperature distribution and pressure distribution were investigated.Under the condition of the same total flow of natural gas,the impact of the number of inlets on the desulfurization efficiency,atmosphere mass fraction distribution and temperature distribution in the furnace was further investigated.
基金Project(2023JH3/10200010)supported by the Excellent Youth Natural Science Foundation of Liaoning Province,ChinaProject(XLYC2203167)supported by the Liaoning Revitalization Talents Program,China+2 种基金Project(RC231175)supported by the Mid-career and Young Scientific and Technological Talents Program of Shenyang,ChinaProject(2023A03003-2)supported by the Key Special Program of Xinjiang,ChinaProject(N2301026)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Nickel laterite ore is an important nickel-bearing mineral.Research on pre-heating and hydrogen pre-reduction in the pyrometallurgical process of nickel laterite ore is very limited,especially when using fluidized bed roasting.This study systematically explores the mechanisms of fluidized bed pre-heating treatment and hydrogen pre-reduction in the roasting process of saprolitic nickel laterite ore.According to single-factor experiment results,the appropriate pre-heating and pre-reduction conditions were a pre-heating temperature of 700℃,a pre-heating time of 30 min,a pre-reduction temperature of 700℃,a pre-reduction time of 30 min,and a hydrogen concentration of 80%.Then,the nickel metallization rate and iron metallization rate reached 90.56%and 41.31%,respectively.Various analytical and testing methods were employed to study the changes in phase composition,magnetism,surface element valence states,and microstructure of nickel laterite ore during fluidized pre-heating and pre-reduction.The study shows that hydrogen can achieve nickel reduction at relatively low temperatures.It was also found that pre-heating treatment of nickel laterite ore is beneficial.Pre-heating opens up the mineral structures of serpentine and limonite,allowing the reducing gas and nickel to interact quickly during the reduction process,enhancing the pre-reduction process.
基金sponsored by the National Key Research and Development Program of China(No.2022YFA1506200)the CNPC Innovation Found(No.2024DQ02-0203)the open foundation of State Key Laboratory of Chemical Engineering(No.SKL-ChE-23B02).
文摘By large-scale cold mold experiments,pressure pulsation signals within the jet influence zone of riser reactor are processed by using Hilbert-Huang analysis(HHT)in this study.Effects of different jet forms and operating conditions on the intrinsic mode function(IMF)energy and Hilbert-Huang spectrum are compared.Results show that the IMF energy and Hilbert-Huang spectrum of pressure pulsation signals show significant differences under the influence of upward and downward jets.Moreover,the change of jet velocity will also lead to significant changes in IMF energy and Hilbert-Huang spectrum.Among them,energy values and energy proportions corresponding to high-frequency pressure pulsations show a good correlation with the jet velocity.On this basis,energy value and energy proportion data in the high frequency range of the original pressure signal are clustered and analyzed by using the K-means clustering algorithm.Based on clustering results,the jet influence zone of riser can be defined into three regions.From partitioning results,it is found that the introduction of downward inclined jets could effectively improve the gas-solid mixing in the feed injection zone of riser.
基金National Key Research and Development Program of China(2021YFA1501302)the National Natural Science Foundation of China(22121004,22122808)+1 种基金the Haihe Laboratory of Sustainable Chemical Transformations and the Program of Introducing Talents of Discipline to Universities(BP0618007)for financial supportsupported by the XPLORER PRIZE.
文摘Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is approximated by the Gaussian distribution and added to experimental capacitance data with various intensities.The equivalent signal strength(Ф)that equals the signal-to-noise ratio of packed beds is used to evaluate noise levels.Results show that the Pearson correlation coefficient,which indicates the similarity of solids fraction distributions over pixels,increases with Ф,and reconstructed images are more deteriorated at lower Ф.Nevertheless,relative errors for average solids fraction and bubble size in each frame are less sensitive to noise,attributed to noise compromise caused by the process of pixel values.These findings provide useful guidance for assessing the accuracy of ECT measurements of multiphase flows.
基金supported by Shandong Provincial Natural Science Foundation(ZR2023MB038)Youth Innovation Team Program of Shandong Higher Education Institution(2022KJ156)。
文摘A feasible criterion was established to determine the lower size limit of raw coal(d_(pRm))for efficient beneficiation in the air-fluidized bed with magnetite particles.The feasibility of using small magnetite particles to accommodate the fine raw coal was demonstrated from the experimental perspective.The minimum size for the magnetite particles to be fluidized smoothly was clarified as 47.1μm,which corresponded to the border between Geldart-B and-A groups.Since the gangue and coal components in the raw coal were crushed into the same size,d_(pRm)depended on the greater one between d_(pGm)(minimum size required for the gangue particles to sink towards the bottom)and d_(pCm)(minimum size required for the coal particles to float towards the top).dpcm was determined as 259μm by supposing that provided the gangue particles accumulated in the lower half bed,they could be potentially extracted from the bottom.On the other hand,it was observed that the coal particles could always accumulate in the upper half bed.Under such circumstances,dpcm was revealed as 9.8μm since finer coal particles would be blown out by air before the 47.1μm sized magnetite particles became fluidized.Eventually,dpRm was clarified as 259μm,agreeing with the common view that raw coal coarser than 6 mm could be effectively beneficiated in the air-fluidized bed with magnetite particles.Additionally,the difficulty in beneficiating the fine raw coal was revealed to arise more from the remixing of sorted gangue particles than that of separated coal particles.
基金supported in part by the National Key Research and Development Program of China(2022YFB3304900)in part by the National Natural Science Foundation of China(62394340 and 62073340)in part by the Science and Technology Innovation Program of Hunan Province(2022JJ10083).
文摘With the intelligent transformation of process manufacturing,accurate and comprehensive perception information is fundamental for application of artificial intelligence methods.In zinc smelting,the fluidized bed roaster is a key piece of large-scale equipment and plays a critical role in the manufacturing industry;its internal temperature field directly determines the quality of zinc calcine and other related products.However,due to its vast spatial dimensions,the limited observation methods,and the complex multiphase,multifield coupled reaction atmosphere inside it,accurately and timely perceiving its temperature field remains a significant challenge.To address these challenges,a spatial-temporal reduced-order model(STROM)is proposed,which can realize fast and accurate temperature field perception based on sparse observation data.Specifically,to address the difficulty in matching the initial physical field with the sparse observation data,an initial field construction based on data assimilation(IFCDA)method is proposed to ensure that the initial conditions of the model can be matched with the actual operation state,which provides a basis for constructing a high-precision computational fluid dynamics(CFD)model.Then,to address the high simulation cost of high-precision CFD models under full working conditions,a high uniformity(HU)-orthogonal test design(OTD)method with the centered L2 deviation is innovatively proposed to ensure high information coverage of the temperature field dataset under typical working conditions in terms of multiple factors and levels of the component,feed,and blast parameters.Finally,to address the difficulty in real-time and accurate temperature field prediction,considering the spatial correlation between the observed temperature and the temperature field,as well as the dynamic correlation of the observed temperature in the time dimension,a spatial-temporal predictive model(STPM)is established,which realizes rapid prediction of the temperature field through sparse observa-tion data.To verify the accuracy and validity of the proposed method,CFD model validation and reduced-order model prediction experiments are designed,and the results show that the proposed method can realize high-precision and fast prediction of the roaster temperature field under different working conditions through sparse observation data.Compared with the CFD model,the prediction root-mean-square error(RMSE)of STROM is less than 0.038,and the computational efficiency is improved by 3.4184×10^(4)times.In particular,STROM also has a good prediction ability for unmodeled conditions,with a prediction RMSE of less than 0.1089.
基金2023 Nantong Jianghai Talents Project,the Nantong Social Livelihood Science and Technology Plan for 2023the 2022 New Drugs and Platform Enhancement Project of the Yangtze Delta Drug Advanced Research Institute.Additionally,support was provided by the Zhenjiang Science and Technology Project(Grant No.SH2020048)+2 种基金the China Postdoctoral Science Foundation(Grant No.2020M681532)the Jiangsu Planned Projects for Postdoctoral Research Funds(Grant No.2020Z209)the Natural Science Research Projects of Universities in Jiangsu Province(Grant No.20KJD350001).
文摘The aim of this study was to develop a novel pharmaceutical excipient:an anion exchange resin.Initially,polystyrenedivinylbenzene(PS-DVB)microspheres were synthesized via suspension polymerization.Subsequently,these microspheres served as a substrate for chloromethylation using methanol,formaldehyde,and chlorosulfonic acid.By optimizing the reaction conditions,the chloromethylated microspheres were characterized using infrared spectroscopy,scanning electron microscopy,and the Mohr method.Under optimal reaction conditions,the resulting products exhibited uniformity and spherical morphology,with an average particle size of approximately 190μm.The PS-DVB microspheres effectively incorporated chloromethyl groups,as evidenced by a chlorine content of 14.67%.Scanning electron microscopy analysis indicated that the appearance of the microspheres remained largely unchanged post-reaction.Overall,the research findings demonstrated the successful preparation of the anion exchange resin.Characterization and quality assessment confirmed that the ion exchange resin met the required standards.
基金supported by the National Natural Science Foundation of China(21808214)Research Project Supported by Shanxi Scholarship Council of China(2023-126)Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(20220013)。
文摘Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really uniform films.This work combining nanoparticle fluidization technology with atomic layer deposition(ALD) technology to achieve precise surface modification of a large number of micro-nano particles.First,we explored the fluidization characteristics of TiO_(2) nanoparticles in a home-made atmospheric fluidized bed ALD reactor(FB-ALD) to ensure the uniform fluidization of a large number of nanoparticles.Then TiCl_(4) and H_(2)O were used as precursors to deposit amorphous TiO_(2) films on the surface of TiO_(2) nanoparticles at 80℃ under atmospheric pressure,and the growth per cycle was about 0.109 nm per cycle.After 30 ALD cycles,the film thickness was about 3.1 nm,which could almost fully suppress the photocatalytic activity of TiO_(2).Compared with other traditional coating materials,amorphous TiO_(2) has higher light refractive index,and realizes the suppression of the photocatalytic activity of TiO_(2) without introducing other substances,demonstrating greater application potential in TiO_(2) pigment coating field.The process is a gas-phase coating method,which is efficient,no waste water,and easy to scale up.This work shown the excellent property of interface engineering in improving pigment weatherability and can also provide guidance for the nanoparticle surface modification.
基金supported by the open foundation of State Key Laboratory of Chemical Engineering(SKL-ChE-22B01)the Natural Science Foundation of China(22008169).
文摘The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this study proposes an innovative hybrid approach that integrates wavelet neural network(WNN)with chaos analysis.By leveraging the Cross-Correlation(C−C)method,the minimum embedding dimension for phase space reconstruction is systematically calculated and then adopted as the input node configuration for the WNN.Simulation results demonstrate the remarkable effectiveness of this integrated method in predicting pressure drop signals,advancing our understanding of the intricate dynamic phenomena occurring with V−L−S fluidized bed evaporators.Moreover,this study offers a novel perspective on applying advanced data-driven techniques to handle the complexities of multi-phase flow systems and highlights the potential for improved operational prediction and control in industrial settings.
基金supported by the National Natural Science Foundation of China(52306131)the Natural Science Foundation of Jiangsu Province(BK20230847)+1 种基金the Key Project of the National Natural Science Foundation of China(52336005)the Open Project Program of State Key Laboratory of Low-carbon Smart Coalfired Power Generation and Ultra-clean Emission(D2024FK156).
文摘Pressurized oxy-fuel combustion is a next-generation and low-cost carbon capture technology with industrial application potential.This work presents an innovative research exploration-coupling coal pressurized fluidized bed oxy-fuel combustion technology with energy utilization of poultry manure as a renewable and carbon-neutral fuel,in order to capture CO_(2)and solve the problem of poultry manure treatment simultaneously.In this study,a stable co-combustion of coal and chicken manure in a laboratory-scale pressurized fluidized bed under typical oxy-fuel condition(30%O_(2)/70%CO_(2),i.e.,Oxy-30)is achieved.The key parameters including the combustion pressure(0.1-0.5 MPa)and chicken-manure proportion(0%to 100%)and their impacts on fundamental combustion efficiency,carbon conversion,nitrogen and sulfur pollutant emissions,and residue ash characteristics have been investigated.The result show that pressurization favors an increase in the CO_(2)enrichment concentration and fluidized bed combustion efficiency.During co-combustion under 0.1 and 0.3 MPa,the CO_(2)concentration in the flue gas is the highest when the chicken manure blending ratio(M_(pm))is 25%.Although the NO emissions fluctuate and even increase as Mpm increases,the co-combustion of coal and chicken manure exhibits a synergistic effect in reducing NO conversion rate(XNO).The effect of pressurization on reducing NO emission is significant,XNO at M_(pm)=25%decreasing from 15%to 5%as the pressure(P)increases from 0.1 to 0.5 MPa.As P increases from 0.1 to 0.5 MPa and Mpm increases from 0%to 50%,the SO_(2) emissions and conversion rates decrease.The self-desulfurization process plays an important role in the reduction of SO_(2) emissions during pressurized oxy-fuel co-combustion.The aim of this work is to advance the development and application of pressurized fluidized bed oxy-fuel co-combustion technology and promote a circular bioeconomy and carbon-free waste management for biomass derived from livestock manure.
文摘For the treatment of the mixed flue gas desulfurization wastewater with high salinity by the biological fluidized bed process,the optimum temperature was 25-35℃,and the optimum hydraulic retention time was 10 h.When the influent quality was stable,the average concentration of COD,NH_(4)^(+)-N and TN in the inlet water was 210,11 and 16.3 mg/L,respectively,and their average concentration in the effluent was 54,0.32 and 4.09 mg/L,respectively.The treatment effect was good.When the incoming water quality of flue gas desulfurization wastewater fluctuated greatly,the effluent quality was still relatively stable after being treated by the biological fluidized bed,indicating that the biological fluidized bed process had a good ability to resist the impact of water quality in the treatment of high-salinity flue gas desulfurization wastewater.At the same time,the biological fluidized bed process provides a reference for high-salinity wastewater that is difficult to be biologically treated.
基金Funded by the China Construction Shares Technology Research and Development Project(No.CSCEC-2023-Z-07)CSCEC Strait Major Scientific and Technological Project(No.ZJHX2023C001)+1 种基金Engineering Research Center of Prevention and Control of Geological Disasters in the Mountainous Areas of Northern Fujian,Fujian Province University,China(No.WYERC2024-3)Science s of Fujian Province(No.2023J01476)。
文摘Fluidized solidified soil(FSS)is an innovative backfill material that offers benefits such as easy pumping and straightforward construction.This study examined how varying the water-soil ratio and the curing agent dosage affect the properties and microstructure of FSS.The strength development mechanism was investigated when composite solidification agents were used.The findings show that both the water-solid ratio and the curing agent dosage can affect the microstructure of FSS,thereby affecting its performance.When the water-solid ratio increases from 0.52 to 0.56,the unconfined compressive strength(UCS)and flexural strength of the FSS decrease by 34.1% and 39.3% after 28 d.Conversely,the curing agent dosage increasing from 10% to 30% will increase both UCS and flexural strength by 11.2 times and 11.1 times.As the curing age increases,the number of cracks at failure point in the FSS will increase and lead to a more complete failure.Numerous needle-like AFt,C-S-H gel,and C-(A)-S-H gel create a three-dimensional network by adhering to soil particles.
基金supported by the Haiyou Program for Industry Leading Talent Innovation Team Project(No.1362022088)。
文摘A novel inverted advanced treatment process of ozone/hydrogen peroxide(O_(3)/H_(2)O_(2))and biological activated carbon fluidized bed(BACFB)before the conventional process has been developed to treat the high-algae-laden reservoir water,which aims to enhance the removal of dissolved organic matter(DOM),odorants as well as the precursors of disinfection by-products(DBPs).Before and after the renovation,the average value of chemical oxygen demand(determined by potassium permanganate method)in the filter effluent decreased from 2.18 to 1.15 mg/L.Likewise,the average concentrations of turbidity dropped from 0.640 to 0.098 NTU,indicating substantial improvement following the renovation.Formation potential of DBPs such as trihalomethanes and haloacetic acids were also reduced greatly.The results of the polarity rapid analysis method indicated that ozonation primarily removed non-polar and positively charged organic matter,while coagulation-sedimentation targeted non-positive organic matter.The results of fluorescence spectroscopy and highresolution mass spectrometry indicated that the new process effectively removed DOM,and decreased the number of nitrogen-containing compounds.Additionally,the inverted O_(3)/H_(2)O_(2) and BACFB process promoted the dynamic transformation between DOM components and significantly reduced overall aromatic content.This study provided a promising solution for treating high-algae-laden source water and verified the feasibility and effectiveness of this novel process in practice.
基金Project (2012BAF03B01) supported by the National Science and Technology Support Program of ChinaProject (2011AA060701) supported by the Hi-tech Research and Development Program of China
文摘To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic ratio （molar ratio of Na2O to Al2O3 in the sodium aluminate solution） of 25, a molar ratio of CaO to SiO2 in the fly ash of 1.1, a liquid volume to solid mass ratio of 9, a reaction temperature of 280 ℃, and a residence time of 1 h when treating fly ash with an alumina to silica mass ratio （A/S） of 0.78 and an alumina content of 32.43%. Additionally, the alumina leaching mechanism was explored via structural and chemical analysis, which revealed that after alkaline digestion, the main solid phase containing silica was NaCaHSiO4 with a theoretical A/S of zero.
基金Projects(51374064,51004033,51074044)supported by the National Natural Science Foundation of ChinaProject(2012AA062303)supported by High-tech Research and Development Program of China
文摘Natural rutile and gaseous chlorine with carbon as reductant were used to prepare titanium tetrachloride. Thermodynamics and kinetics of chlorination of Kenya natural rutile particles in a batch-type fluidized bed were studied at 1173-1273 K. Thermodynamic analysis of this system revealed that the equation of producing CO was dominant at high temperatures. Based on the gas-solid multi-phase reaction theory and a two-phase model for the fluidized bed, the mathematical description for the chlorination reaction of rutile was proposed. The reaction parameters and the average concentration of gaseous chlorine in the emulsion phase were estimated. The average concentration of emulsion phase in the range of fluidized bed was calculated as 0.3 mol/m^3. The results showed that the chlorination of natural rutile proceeded principally in the emulsion phase, and the reaction rate was mainly controlled by the surface reaction.
基金The National Natural Science Foundation of China(No.51206023)the National Key Basic Research Program of China(973 Program)(No.2011CB707301-3)the Fundamental Research Funds for the Central Universities
文摘The pressurized combustion experiments of bituminous coal and lignite under air and O2/CO2 atmospheres were conducted to study the influences of pressure and atmosphere on combustion and the CO, NO, SO2 release process. Two indices, the maximum concentration and the total emission, were applied to quantitatively evaluate the influence of several different operating parameters such as pressure, atmosphere and temperature on the formation of NO and SO2 during coal combustion in the fluidized bed. The experimental results show that the releasing profiles of CO, NO and SO2 during coal combustion under a pressurized oxy- fuel atmosphere are similar to those under a pressurized air atmosphere, and the curves of measured gas components are all unimodal. Under the oxy-fuel condition, pressure increasing from 0.1 to 0.7 MPa can cause the inhibition of NO and SO2 emission. The elevation of temperature can lead to an increase in the maximum concentration and the total production of NO and SO2, and the increase under atmospheric pressure is higher than that under high pressure.
基金Project(2008AA06Z1071) supported by the National High-Tech Research and Development Program of ChinaProject(20306030) supported by the National Natural Science Foundation of China
文摘In order to solve the agglomeration problem in TiCl4 preparation,a new test in a multistage series combined fluidized bed was studied on a pilot scale.The pilot plant can make full use of titanium slag with a high content of MgO and CaO as the feedstock.Several experimental parameters such as chlorine flow and reaction temperature were discussed and the morphology and components of reaction product were analyzed.According to the results,the conversion rate of TiO2 is up to 90%.It is found that the combined fluidized bed has good anti-agglomeration ability because the accumulation of MgCl2 and CaCl2 on the surface of unreacted slag was carried out of the reactor.
