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Liquid-phase esterification of methacrylic acid with methanol catalyzed by cation-exchange resin in a fixed bed reactor:Experimental and kinetic studies
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作者 Junyang Liu Luming Wang +3 位作者 Yuhang Bian Chunshan Li Zengxi Li Jie Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期1-10,共10页
The kinetic behavior of esterification between methacrylic acid and methanol catalyzed by NKC-9 resin was studied in a fixed bed reactor.The reaction was conducted in the temperature range of 323.15 to 368.15 K with t... The kinetic behavior of esterification between methacrylic acid and methanol catalyzed by NKC-9 resin was studied in a fixed bed reactor.The reaction was conducted in the temperature range of 323.15 to 368.15 K with the molar ratio of reactants from 0.8 to 1.4 under certain pressure.The measurement data were regression with the pseudo-homogeneous(P-H),Eley-Rideal(E-R),and Langmuir-Hinshelwood(L-H)heterogeneous kinetic models.Independent adsorption experiments were implemented to gain the adsorption equilibrium constants of four components.Among the above three models,the L-H model exhibited the best fitting results.The stability of NKC-9 was evaluated by long-term running with the yield of methyl methacrylate no decrease during 3000 h operation.The structure and physicochemical properties of the new and used catalyst were performed by several characterizations including thermogravimetric analysis(TG),scanning electron microscope(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR)and so on. 展开更多
关键词 Kinetics ESTERIFICATION Methyl methacrylate Cation-exchange resin Fix bed reactor
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Time-resolved characteristics of a nanosecond pulsed multi-hollow needle plate packed bed dielectric barrier discharge
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作者 秦亮 李瑶 +6 位作者 郭浩 姜楠 宋颖 贾锐 周雄峰 袁皓 杨德正 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期48-57,共10页
In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and ac... In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and achieve large-volume stable discharge.The dynamic characteristics of the plasma,the generated active species,and the energy transfer mechanisms in both positive discharge(PD)and negative discharge(ND)are investigated by using fast-exposure intensified charge coupled device(ICCD)images and time-resolved optical emission spectra.The experimental results show that the discharge intensity,number of discharge channels,and discharge volume are obviously enhanced when the multi-needle electrode is replaced by a multihollow needle electrode.During a single voltage pulse period,PD mainly develops in a streamer mode,which results in a stronger discharge current,luminous intensity,and E/N compared with the diffuse mode observed in ND.In PD,as the gap between dielectric beads changes from 0 to250μm,the discharge between the dielectric bead gap changes from a partial discharge to a standing filamentary micro-discharge,which allows the plasma to leave the local area and is conducive to the propagation of surface streamers.In ND,the discharge only appears as a diffusionlike mode between the gap of dielectric beads,regardless of whether there is a discharge gap.Moreover,the generation of excited states N_(2)^(+)(B^(2)∑_(u)^(+))and N2(C^(3)Π_(u))is mainly observed in PD,which is attributed to the higher E/N in PD than that in ND.However,the generation of the OH(A^(2)∑^(+))radical in ND is higher than in PD.It is not directly dominated by E/N,but mainly by the resonant energy transfer process between metastable N_(2)(A^(3)∑_(u)^(+))and OH(X^(2)Π).Furthermore,both PD and ND demonstrate obvious energy relaxation processes of electron-to-vibration and vibration-to-vibration,and no vibration-to-rotation energy relaxation process is observed. 展开更多
关键词 packed bed reactor multi-hollow needle electrodes positive and negative discharges optical emission spectra time-resolved images
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Performance of Anammox granular sludge bed reactor started up with nitrifying granular sludge 被引量:17
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作者 ZHENGPing LINFeng-mei +1 位作者 HUBao-lan CHENJian-song: 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期339-342,共4页
The anaerobic ammonia oxidation(Anammox) granular sludge bed reactor was started up successfully with nitrifying granular sludge. During the operation, the nitrifying granular sludge was gradually converted into Anamm... The anaerobic ammonia oxidation(Anammox) granular sludge bed reactor was started up successfully with nitrifying granular sludge. During the operation, the nitrifying granular sludge was gradually converted into Anammox granular sludge with good settling property and high conversion activity. The Anammox reactor worked well with the shortest HRT of 2 43 h. Under the condition that HRT w as 6 39 h and influent concentration of ammonia and nitrite was 10 mmol/L, the removal of ammonia and nitrite was 97 17% and 100 00%, respectively. Corresponding volumetric total nitrogen loading rate and volumetric total nitrogen conversion rate were 100 83 mmol/(L·d) and 98 95 mmol/(L·d). The performance of Anammox reactor was efficient and stable. 展开更多
关键词 nitrifying granular sludge anaerobic ammonia oxidation(Anammox) granular sludge bed reactor PERFORMANCE
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Oxidative coupling of methane in a fixed bed reactor over perovskite catalyst:A simulation study using experimental kinetic model 被引量:8
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作者 Nakisa Yaghobi Mir Hamid Reza Ghoreishy 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第1期8-16,共9页
The oxidative coupling of methane (OCM) to ethylene over a perovskite titanate catalyst in a fixed bed reactor was studied experimentally and numerically. The two-dimensional steady state model accounted for separat... The oxidative coupling of methane (OCM) to ethylene over a perovskite titanate catalyst in a fixed bed reactor was studied experimentally and numerically. The two-dimensional steady state model accounted for separate energy equations for the gas and solid phases coupled with an experimental kinetic model. A lumped kinetic model containing four main species CH4, O2, COx (CO2, CO), and C2 (C2H4 and C2H6) was used with a plug flow reactor model as well. The results from the model agreed with the experimental data. The model was used to analyze the influence of temperature and feed gas composition on the conversion and selectivity of the reactor performance. The analytical results indicate that the conversion decreases, whereas, C2 selectivity increases by increasing gas hourly space velocity (GHSV) and the methane conversion also decreases by increasing the methane to oxygen ratio. 展开更多
关键词 oxidative coupling of methane SIMULATION KINETICS fixed bed catalytic reactor ETHYLENE
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Anaerobic tapered fluidized bed reactor for starch wastewater treatment and modeling using multilayer perceptron neural network 被引量:8
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作者 RANGASAMY Parthiban PVR Iyer GANESAN Sekaran 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第12期1416-1423,共8页
treatability of synthetic sago wastewater was investigated in a laboratory anaerobic tapered fluidized bed reactor (ATFBR) with a mesoporous granular activated carbon (GAC) as a support material. The experimental ... treatability of synthetic sago wastewater was investigated in a laboratory anaerobic tapered fluidized bed reactor (ATFBR) with a mesoporous granular activated carbon (GAC) as a support material. The experimental protocol was defined to examine the effect of the maximum organic loading rate (OLR), hydraulic retention time (HRT), the efficiency of the reactor and to report on its steady- state performance. The reactor was subjected to a steady-state operation over a range of OLR up to 85.44 kg COD/(m^3·d). The COD removal efficiency was found to be 92% in the reactor while the biogas produced in the digester reached 25.38 m^3/(m^3·d) of the reactor. With the increase of OLR from 83.7 kg COD/(m^3·d), the COD removal efficiency decreased. Also an artificial neural network (ANN) model using multilayer perceptron (MLP) has been developed for a system of two input variable and five output dependent variables. For the training of the input-output data, the experimental values obtained have been used. The output parameters predicted have been found to be much closer to the corresponding experimental ones and the model was validated for 30% of the untrained data. The mean square error (MSE) was found to be only 0.0146. 展开更多
关键词 anaerobic digestion tapered fluidized bed reactor organic loading rate BIOGAS mesoporous granular activated carbon modeling artificial neural network
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Production of single-walled carbon nanotubes from methane over Co-Mo/MgO nanocatalyst:A comparative study of fixed and fluidized bed reactors 被引量:4
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作者 Alimorad Rashidi Roghayeh Lotfi +1 位作者 Ehsaneh Fakhrmosavi Masoud Zare 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第4期372-376,共5页
In this study,the performances of fixed and fluidized bed reactors in the production of single-walled carbon nanotubes(SWNTs)have been investigated.In both reactors,single-walled carbon nanotubes were grown by catal... In this study,the performances of fixed and fluidized bed reactors in the production of single-walled carbon nanotubes(SWNTs)have been investigated.In both reactors,single-walled carbon nanotubes were grown by catalytic chemical vapor decomposition(CCVD)of methane over Co-Mo/MgO nanocatalyst under two different operating conditions.The synthesized samples were characterized by TEM,TGA and Raman spectroscopy.It is found that the performance of a fluidized bed in the synthesis of carbon nanotubes is much better than that of a fixed bed.The quality of carbon nanotubes obtained from the fluidized bed was significantly higher than that from the fixed bed and the former one with the ID/IG ratio of 0.11 while the latter one with the ID/IG ratio of 0.71.Also,the yield of SWNTs in the fluidized bed was 92 wt%,while it was 78 wt%in the fixed bed.These advantages of fluidized bed reactors for the synthesis of carbon nanotubes can be attributed to more available space for the growth of carbon nanotubes and more uniform temperature and concentration profiles. 展开更多
关键词 single-walled carbon nanotubes chemical vapor deposition fixed bed reactor fluidized bed reactor
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A Review of Techniques for the Process Intensification of Fluidized Bed Reactors 被引量:11
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作者 张维 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期688-702,共15页
Fluidized beds enable good solids mixing,high rates of heat and mass transfer,and large throughputs,but there remain issues related to fluidization quality and scale-up.In this work I review modification techniques fo... Fluidized beds enable good solids mixing,high rates of heat and mass transfer,and large throughputs,but there remain issues related to fluidization quality and scale-up.In this work I review modification techniques for fluidized beds from the perspective of the principles of process intensification(PI),that is,effective bubbling suppression and elutriation control.These techniques are further refined into(1)design factors,e.g.modifying the bed configuration,or the application of internal and external forces,and(2)operational factors,including altering the particle properties(e.g.size,density,surface area)and fluidizing gas properties(e.g.density,viscosity,or velocity).As far as two proposed PI principles are concerned,our review suggests that it ought to be possible to gain improvements of between 2 and 4 times over conventional fluidized bed designs by the application of these techniques. 展开更多
关键词 process intensification FLUIDIZATION fluidized bed reactor
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Production of hydrogen and syngas via pyrolysis of bagasse in a dual bed reactor 被引量:3
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作者 Morteza Shoja Mokhtar Akhond Babatabar +1 位作者 Ahmad Tavasoli Abtin Ataei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第4期639-644,共6页
Pyrolysis of bagasse followed by thermal cracking of tar was carded out at atmospheric pressure using a dual bed reactor. The first bed was used for the pyrolysis and the second bed was used for thermal cracking of ta... Pyrolysis of bagasse followed by thermal cracking of tar was carded out at atmospheric pressure using a dual bed reactor. The first bed was used for the pyrolysis and the second bed was used for thermal cracking of tar. Iron fillings were used as the packed bed material in the second bed. The effects of reaction time (20 to 40 rain), reactor temperature (600 to 900 ℃) and packed bed height (40-100 mm) on the product (char, tar and gas) yield and gas (H2, CO, CO2, CH4, CnHm) composition were studied. Over the ranges of the experimental conditions used, the operating conditions were optimized for pyrolysis temperature around 850 ℃, a reaction time of 30 min and packed bed height of 100 mm, thus we could obtain a gas richer in hydrogen and carbon monoxide and poorer in carbon dioxide and hydrocarbons. It was observed that compared with single bed process, dual bed process increased the gas yield from 0.397 to 0.750 m3/kg and decreased the tar yield from 0.445 to 0.268 g/g while the heating value of the product gas remained almost constant (10-11 M J/m3). 展开更多
关键词 BAGASSE dual bed reactor HYDROGEN SYNGAS yield
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Kinetic Model of Fixed Bed Reactor with Immobilized Microorganisms for Removing Low-Concentration SO_2 被引量:3
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作者 Bing Huang YanyanWang +1 位作者 Shiling Zhang Yong Ao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期86-91,共6页
On the basis of the analysis of the process of treating low concentrations of sulfur dioxide (SO2) gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects... On the basis of the analysis of the process of treating low concentrations of sulfur dioxide (SO2) gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors. 展开更多
关键词 fixed bed reactor kinetic model immobilized microorganisms REMOVAL sulfur dioxide
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Investigation of the liquid recycle in the reactor cascade of an industrial scale ebullated bed hydrocracking unit 被引量:2
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作者 Eduard Manek Juma Haydary 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期298-304,共7页
One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scie... One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scientists and research groups. This work is aimed at the calculation of the internal recycle flow rate and understanding its effect on other parameters of the ebullated bed. Measured data were collected from an industrial scale residual hydrocracking unit consisting of a cascade of three ebullated bed reactors. A simplified block model of the ebullated bed reactors was created in Aspen Plus and fed with measured data. For reaction yield calculation, a lumped kinetic model was used. The model was verified by comparing experimental and calculated distillation curves as well as the calculated and measured reactor inlet temperature. Influence of the feed rate on the recycle ratio(recycle to feed flow rate) was estimated. A relation between the recycle flow rate, pump pressure difference and catalyst inventory has been identified. The recycle ratio also affects the temperature gradient along the reactor cascade. Influence of the recycle ratio on the temperature gradient decreased with the cascade member order. 展开更多
关键词 Residual HYDROCRACKING Ebullated bed reactor LIQUID RECYCLE ASPEN Plus Simulation
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Modeling of Isobutane/Butene Alkylation Using Solid Acid Catalysts in a Fixed Bed Reactor 被引量:3
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作者 Liu Zheng Tang Xiaojin +1 位作者 Hu Lifeng Hou Shuandi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第2期63-69,共7页
A dynamic mass transfer model of isobutane/butene alkylation over solid acid catalysts in a fixed bed reactor was established. In the model, a modified equation for the relationship between point activity and effectiv... A dynamic mass transfer model of isobutane/butene alkylation over solid acid catalysts in a fixed bed reactor was established. In the model, a modified equation for the relationship between point activity and effective diffusion coefficient was proposed. It is found that the simulation results fit the experimental data well and the breakthrough time of the bed layer is predicted accurately. By modeling the alkylation process, the time-space distribution of butene and point activity profiles of catalysts can be obtained. Furthermore, the reasons for the deactivation of solid acid catalysts were investigated. It indicates that the main reason for the deactivation of catalysts is the site coverage near the inlet of the reactor, while it is ascribed to the steric effect in the region far away from the inlet. 展开更多
关键词 mass transfer model isobutane/butene ALKYLATION fixed bed reactor DEACTIVATION INTERNAL DIFFUSION
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Cd^(2+) removal from wastewater by sulfate reducing bacteria with an anaerobic fluidized bed reactor 被引量:3
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作者 Ma Xiaohang, Hua Yaoxi, Jiang Feng Institute of Microbiology of Zhejiang Province, Hangzhou 310012, China Liu Jian Environmental Protection Institute of Zhejiang Province, Hangzhou 310007, China Ye Xieming Metallurgical Institute of Zheji 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期113-118,共6页
A process of treatment for containing Cd 2+ wastewater by sulfate reducing bacteria with upflow anaerobic fluidized bed reactor has been studied. When the concentration of COD and Cd 2+ in the influent were... A process of treatment for containing Cd 2+ wastewater by sulfate reducing bacteria with upflow anaerobic fluidized bed reactor has been studied. When the concentration of COD and Cd 2+ in the influent were 270 5mg/L and 100mg/L respectively and hydraulic retention time was 4 hours, the removal rate of COD and Cd 2+ were higher than 73 8% and 99 8% respectively. The reactor can treat as high as 1000mg/L of concentration of Cd 2+ . The highest removal velocity rate of Cd 2+ reached 2999 1mg/(L·d). And the possible relationship between sulfate reducing bacteria and methanogenic bacteria was discussed. 展开更多
关键词 Cd 2+ removal sulfate reducing bacteria anaerobic fluidized bed reactor.
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Hydrogen production by catalytic decomposition of methane using a Fe-based catalyst in a fluidized bed reactor 被引量:3
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作者 D.Torres S.deLlobet +3 位作者 J.L.Pinilla M.J.Lzaro I.Suelves R.Moliner 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第4期367-373,共7页
Catalytic decomposition of methane using a Fe-based catalyst for hydrogen production has been studied in this work. A Fe/Al2O3 catalyst previously developed by our research group has been tested in a fluidized bed rea... Catalytic decomposition of methane using a Fe-based catalyst for hydrogen production has been studied in this work. A Fe/Al2O3 catalyst previously developed by our research group has been tested in a fluidized bed reactor (FBR). A parametric study ot the effects of some process variables, including reaction temperature and space velocity, is undertaken. The operating conditions strongly affect the catalyst performance. Methane conversion was increased by increasing the temperature and lowering the space velocity. Using temperatures between 700 and 900℃ and space velocities between 3 and 6 LN/(gcat·h), a methane conversion in the range of 25%-40% for the gas exiting the reactor could be obtained during a 6 h run. In addition, carbon was deposited in the form of nanofilaments (chain like nanofibers and multiwall nanotubes) with similar properties to those obtained in a fixed bed reactor. 展开更多
关键词 hydrogen production fluidized bed reactor metal catalysts
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Improved Generalized Predictive Control Algorithm with Offline and Online Identification and Its Application to Fixed Bed Reactor 被引量:4
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作者 余世明 王海清 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第1期49-54,共6页
An improved generalized predictive control algorithm is presented in thispaper by incorporating offline identification into online identification. Unlike the existinggeneralized predictive control algorithms, the prop... An improved generalized predictive control algorithm is presented in thispaper by incorporating offline identification into online identification. Unlike the existinggeneralized predictive control algorithms, the proposed approach divides parameters of a predictivemodel into the time invariant and time-varying ones, which are treated respectively by offline andonline identification algorithms. Therefore, both the reliability and accuracy of the predictivemodel are improved. Two simulation examples of control of a fixed bed reactor show that this newalgorithm is not only reliable and stable in the case of uncertainties and abnormal disturbances,but also adaptable to slow time varying processes. 展开更多
关键词 generalized predictive control offline identification onlineidentification fixed bed reactor
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Dynamics and Predictive Control of Gas Phase Propylene Polymerization in Fluidized Bed Reactors 被引量:4
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作者 Ahmad Shamiri Mohamed azlan Hussain +2 位作者 Farouq sabri Mjalli Navid Mostoufi Seyedahmad Hajimolana~ 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期1015-1029,共15页
A two-phase dynamic model, describing gas phase propylene polymerization in a fluidized bed reactor, was used to explore the dynamic behavior and process control of the polypropylene production rate and reactor temper... A two-phase dynamic model, describing gas phase propylene polymerization in a fluidized bed reactor, was used to explore the dynamic behavior and process control of the polypropylene production rate and reactor temperature. The open loop analysis revealed the nonlinear behavior of the polypropylene fluidized bed reactor, jus- tifying the use of an advanced control algorithm for efficient control of the process variables. In this case, a central- ized model predictive control (MPC) technique was implemented to control the polypropylene production rate and reactor temperature by manipulating the catalyst feed rate and cooling water flow rate respectively. The corre- sponding MPC controller was able to track changes in the setpoint smoothly for the reactor temperature and pro- duction rate while the setpoint tracking of the conventional proportional-integral (PI) controller was oscillatory with overshoots and obvious interaction between the reactor temperature and production rate loops. The MPC was able to produce controller moves which not only were well within the specified input constraints for both control vari- ables, but also non-aggressive and sufficiently smooth for practical implementations. Furthermore, the closed loop dynamic simulations indicated that the speed of rejecting the process disturbances for the MPC controller were also acceotable for both controlled variables. 展开更多
关键词 model predictive control fluidized bed reactor propylene polymerization Ziegler-Natta catalyst
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Start-up and Performance of a Novel Reactor----Jet Biogas Inter-loop Anaerobic Fluidized Bed 被引量:2
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作者 邓志毅 韦朝海 周秀峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期143-150,共8页
A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed (JBILAFB), was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose w... A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed (JBILAFB), was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose wastewater treatment. With the wastewater recycle ratio of 2.5 : 1, the recycled wastewater with biogas could mix sludge and wastewater in the JBILAFB reactor completely. The start-up of the JBILAFB reactor could be completed in less than 70 d through maintenance of hydraulic retention time (HR^I") and stepwise increase of feed total organic carbon (TOC) concentration. After the start-up, with the volumetric TOC loadings of 14.3 kg·m ^-3·d^-1, the TOC removal ratio, the effluent pH, and the volatile fatty acids (VFA)/alkalinity of the JBILAFB reactor were more than 80%, close to 7.0 and less than 0.4, respectively. Moreover, CH4 was produced at more than 70% of the theoretical value, The reactor exhibited high stability under the condition of high volumetric TOC loading. Sludge granules in the JBILAFB reactor were developed during the start-up and their sizes were enlarged with the stepwise increase of volumetric TOC loadings from 0.8 kg.m^-3.d ^-1 to 14.3 kg.m^-3.d^-1. Granules, an offwhite color and a similar spherical shape, were mainly comprised of global-like bacteria. These had good methanogenic activity and settleability, which were formed probably through adhesion of the bacteria. Some inorganic metal compounds such as Fe, Ca, Mg, Al, etc. were advantageous to the formation of the granules. 展开更多
关键词 anaerobic reactor jet biogas inter-loop anaerobic fluidized bed wastewater treatment START-UP granule sludge
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Intensification of Deep Hydrodesulfurization Through a Two-stage Combination of Monolith and Trickle Bed Reactors 被引量:1
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作者 许闵 刘辉 +1 位作者 季生福 李成岳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第8期888-897,共10页
Deep hydrodesulfurization (HDS) is an important process to produce high quality liquid fuels with ultra-low sul- fur. Process intensification for deep HDS could be implemented by developing new active catalysts and/... Deep hydrodesulfurization (HDS) is an important process to produce high quality liquid fuels with ultra-low sul- fur. Process intensification for deep HDS could be implemented by developing new active catalysts and/or new types of reactors. In this work, the kinetics of dibenzothiophene (DBT) hydrodesulfurization over Ni-P/SBA-15/ cordierite catalyst was investigated at 340-380 ℃ and 3.0-5.0 MPa. The first-order reaction model with respect to both DBT and H2 was used to fit the kinetics data in a batch recycle operation system. It is found that both the activation energy and rate constant over the Ni-P monolithic catalyst under our operating conditions are close to those over conventionally used HDS catalysts. Comparative performance studies of two types of reactors, i.e., trickle bed reactor and monolithic reactor, were performed based on reactor modeling and simulation. The results indicate that the productivity of the monolithic reactor is 3 times higher than that of the trickle bed reactor on a catalyst weight basis since effective utilization of the catalyst is higher in the monolithic reactor, but the volumetric productivity of the monolithic reactor is lower for HDS of DBT. Based on simulation results, a two- reactor-in-series configuration for hydrodesulfurization is proposed, in which a monolithic reactor is followed by a tickled bed reactor so as to attain intensified performance of the system converting fuel oil of different sulfur-containing compounds. It is illustrated that the two reactor scheme outperforms the trickle bed reactor both on reactor volume and catalyst mass bases while the content of sulfur is reduced from 200 μg·g-1 to about 10 μ·g-1. 展开更多
关键词 Hydrodesulfurization (HDS) Kinetics Mass transfer Monolithic reactor Trickle bed reactor reactor modeling
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Preparation of Pd/c-Al_(2)O_(3)/nickel foam monolithic catalyst and its performance for selective hydrogenation in a rotating packed bed reactor 被引量:1
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作者 Hai-Long Liao Bao-Ju Wang +4 位作者 Ya-Zhao Liu Yong Luo Jie-Xin Wang Guang-Wen Chu Jian-Feng Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期311-319,共9页
Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass transfer.In this work,the enhanced hydrogenation selectivity was achieved in a rotating packed ... Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass transfer.In this work,the enhanced hydrogenation selectivity was achieved in a rotating packed bed(RPB)reactor with excellent mass transfer efficiency.Aiming to be used under the centrifugal filed,a monolithic catalyst Pd/c-Al_(2)O_(3)/nickel foam suiting for the shape and size of the rotor of RPB reactor was prepared by the electrophoretic deposition method.The mechanical strength of the catalyst can meet the requirement of high centrifugal force in the RPB.The hydrogenation selectivity in the RPB reactor using the 3-methyl-1-pentyn-3-ol hydrogenation system was 3–8 times higher than that in a stirred tank reactor under similar conditions.This work proves the feasibility of intensifying the selectivity of hydrogenation process in the RPB reactor. 展开更多
关键词 Monolithic catalyst Rotating packed bed reactor HYDROGENATION SELECTIVITY
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Absorption Enhanced Methanol Synthesis in a Trickle Bed Reactor over Cu/Zn/Al<sub>2</sub>O<sub>3</sub>Catalyst 被引量:1
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作者 Peng Liu Zhenmin Cheng 《Journal of Materials Science and Chemical Engineering》 2015年第6期27-32,共6页
Methanol synthesis in a trickle bed reactor with tetraethylene glycol dimethyl ether (TEGDME) as the liquid phase over a Cu/Zn/Al2O3 catalyst was investigated. The pressure was kept constant at 5.0 MPa, while the temp... Methanol synthesis in a trickle bed reactor with tetraethylene glycol dimethyl ether (TEGDME) as the liquid phase over a Cu/Zn/Al2O3 catalyst was investigated. The pressure was kept constant at 5.0 MPa, while the temperature ranged from 230℃?to 260℃?and the mass space velocity varied between 294 L·Kg-1·h-1 and 1655 L·Kg-1·h-1. The effects of temperature and space velocity on CO conversion and methanol productivity were studied. Methanol synthesis processes in trickle bed with the TEGDME and paraffin oil as liquid phase were compared with the fixed bed process. The results indicated that the optimal temperature was approximately 240℃. When the space velocity was increased, the CO conversion decreased while the methanol productivity increased. The liquid introduced can help to keep the reactor nearly isothermal. For methanol synthesis in trickle-bed reactor, TEGDME was better than paraffin oil. Effect of TEGDME on the reaction was twofold. On one hand, it absorbs the methanol and speeds up the reaction. On the other hand, it also increases the mass transfer resistance and hinders the reaction. 展开更多
关键词 ABSORPTION METHANOL Synthesis Trickle bed reactor
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Numerical simulation of fixed bed reactor for oxidative coupling of methane over monolithic catalyst 被引量:1
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作者 张照 郭紫琪 季生福 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第10期1627-1633,共7页
A three-dimensional geometric model was set up for the oxidative coupling of methane(OCM) fixed bed reactor loaded with Na_3PO_4-Mn/SiO_2/cordierite monolithic catalyst,and an improved Stansch kinetic model was establ... A three-dimensional geometric model was set up for the oxidative coupling of methane(OCM) fixed bed reactor loaded with Na_3PO_4-Mn/SiO_2/cordierite monolithic catalyst,and an improved Stansch kinetic model was established to calculate the OCM reactions using the computational fluid dynamics method and Fluent software.The simulation conditions were completely the same with the experimental conditions that the volume velocity of the reactant is 80 ml·min^(-1) under standard state,the CH_4/O_2 ratio is 3 and the temperature and pressure is800 ℃ and 1 atm,respectively.The contour of the characteristic parameters in the catalyst bed was analyzed,such as the species mass fractions,temperature,the heat flux on side wall surface,pressure,fluid density and velocity.The results showed that the calculated values matched well with the experimental values on the conversion of CH4 and the selectivity of products(C_2H_6,C_2H_4,CO,CO_2 and H_2) in the reactor outlet with an error range of±4%.The mass fractions of CH_4 and O_2 decreased from 0.600 and 0.400 at the catalyst bed inlet to 0.445 and0.120 at the outlet,where the mass fractions of C_2H_6,C_2H_4,CO and CO_2 were 0.0245,0.0460,0.0537 and 0.116,respectively.Due to the existence of laminar boundary layer,the mass fraction contours of each species bent upwards in the vicinity of the boundary layer.The volume of OCM reaction was changing with the proceeding of reaction,and the total moles of products were greater than reactants.The flow field in the catalyst bed maintained constant temperature and pressure.The fluid density decreased gradually from 2.28 kg·m^(-3) at the inlet of the catalyst bed to 2.18 kg·m^(-3) at the outlet of the catalyst bed,while the average velocity magnitude increased from 0.108 m·s-1 to 0.120 m·s^(-1). 展开更多
关键词 Numerical simulation Fixed bed reactor Computational fluid dynamics Oxidative coupling of methane Monolithic catalyst
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