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Showing papers on "Packed bed published in 2012"


Journal ArticleDOI
TL;DR: In this article, a thermal energy storage system, consisting of a packed bed of rocks as storing material and air as high-temperature heat transfer fluid, is analyzed for concentrated solar power (CSP) applications.

304 citations


Journal ArticleDOI
TL;DR: Carbon dioxide sequestration using the accelerated carbonation of basic oxygen furnace (BOF) slag in a high-gravity rotating packed bed (RPB) under various operational conditions was investigated and acceleration in a RPB was confirmed to be a viable method due to its higher mass-transfer rate.

162 citations


Journal ArticleDOI
Qinqin Yu1, Meng Kong1, Tong Liu1, Jinhua Fei1, Xiaoming Zheng1 
TL;DR: In this article, the decomposition of CO2 in a dielectric packed-bed plasma reactor has been studied, and it was found that the acid-base properties of the packing materials also affect the reaction through the chemisorption of CO 2 on basic sites of the materials.
Abstract: The decomposition of CO2 in a dielectric packed-bed plasma reactor has been studied. It was found that the dielectric properties and morphology of packing dielectric pellets play important roles in the reaction due to their influence on the electron energy distribution in the plasma. The acid–base properties of the packing materials also affect the reaction through the chemisorption of CO2 on basic sites of the materials. Heterogeneous reactions on the solid surfaces of the dielectric materials also play a role in the reaction, which was also confirmed through the investigation of the influence of the discharge length on the reaction. The reverse reaction of CO2 decomposition, the oxidation of CO, was also investigated to further understand the role of dielectric materials in the plasma and their effect on plasma reactions. Both the decomposition of CO2 and the oxidation of CO in non-packed or dielectric packed reactors are first-ordered.

144 citations


Journal ArticleDOI
TL;DR: In this article, an efficient dye biosorbent was developed for the treatment of textile wastewater by entrapping dead cells of C. tropicalis, within a sodium alginate matrix.

132 citations


Journal ArticleDOI
TL;DR: Yang et al. as discussed by the authors investigated the effects of packing form and particle shape on the macroscopic hydrodynamic and heat transfer characteristics in some novel structured packed beds, where the packings of ellipsoidal or non-uniform spherical particles are investigated for the first time with experiments and some important results are obtained.

130 citations


Journal ArticleDOI
TL;DR: In this article, the authors develop dependable, dimensionally consistent, correlating expressions for the mass-transfer related quantities kx, ky, and am for metal Pall rings, metal IMTP, sheet metal structured packings of the MELLAPAK type, and metal gauze structured packing in the X configuration.
Abstract: Rate-based calculations for trayed and packed columns offer process engineers a more rigorous and reliable basis for assessing column performance than the traditional equilibrium-stage approach, especially for multicomponent separations. Although the mathematics, thermodynamics, and transport-related physics upon which nonequilibrium separations theory is founded are generally true, it is also true that rate-based simulations today suffer from a serious weakness—they are ultimately tied to underlying equipment performance correlations with questionable predictive capability. In the case of packed columns operated countercurrently, correlations are required for the mass-transfer coefficients, kx and ky, for the specific area participating in mass transfer, am, for the two-phase pressure drop, (Δp/Z)2ϕ, and for the flood capacity of the column. In particular, it is generally well known that packing mass-transfer correlations available in the public domain are unreliable when they are applied to chemical systems and column operating conditions outside of those used to develop the correlations in the first place. For that reason, we undertake the development of dependable, dimensionally consistent, correlating expressions for the mass-transfer-related quantities kx, ky, and am for metal Pall rings, metal IMTP, sheet metal structured packings of the MELLAPAK type, and metal gauze structured packings in the X configuration, using a new data fitting procedure. We demonstrate the superior performance of these correlations for a wide range of chemical systems and column operating conditions, including distillations as well as acid gas capture with amines. Further, we show that these new correlations lead to predictions for the relative interfacial area participating in mass transfer that can be greatly in excess of the geometrical surface area of the packing itself. © 2011 American Institute of Chemical Engineers AIChE J, 2012

118 citations


Journal ArticleDOI
Hairong Yue1, Yujun Zhao1, Li Zhao1, Jing Lv1, Shengping Wang1, Jinlong Gong1, Xinbin Ma1 
TL;DR: In this paper, a Cu/SiO2-based monolithic catalyst for hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG) is presented.
Abstract: The design and application of a Cu/SiO2-based monolithic catalyst for hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG) is presented. The catalyst was dip-coated on cordierite with highly dispersed Cu/SiO2 slurry prepared by ammonia evaporation method. This structure guarantees high dispersion of copper species within the mesopores of silica matrix in the form of copper phyllosilicate. The catalyst is low cost, stable, and exhibits high activity in the reaction of hydrogenation of DMO, achieving a 100% conversion of DMO and more than 95% selectivity to EG. Notably, STYEG over the monolith is significantly enhanced compared to the packed bed Cu/SiO2 catalysts in both forms of pellet and cylinder. It is primarily due to the relatively short diffusive pathway of the thin wash-coat layer and high efficiency of the active phase derived from the monolithic catalyst. Theoretical results indicated that the internal mass transfer is dominated on the catalysts of pellet and cylinders. Moreover, the monolithic catalyst possessed excellent thermal stability compared to the pellet catalyst, which is attributed to the regular channel structure, uniform distribution of flow. © 2011 American Institute of Chemical Engineers AIChE J, 2012

117 citations


Journal ArticleDOI
TL;DR: The granule-packed column could efficiently remove different metals from real industrial effluents, and hence the test biomass (Spirogyra granules) is a good candidate for commercial application.

106 citations


Journal ArticleDOI
TL;DR: In this paper, the gas-liquid effective interfacial area of a conventional RPB was studied with eight types of stainless steel wire mesh packings, consisting of four different stainless steel fibers.
Abstract: Stainless steel wire mesh packing is widely used for experimental and industrial applications in rotating packed beds (RPBs) for gas–liquid contacting because it has a higher mass-transfer performance than other conventional packings. In this work, the gas–liquid effective interfacial area of a conventional RPB was studied with eight types of stainless steel wire mesh packings, consisting of four different stainless steel fibers. Gas–liquid chemisorption with CO2 in NaOH solution was employed to measure the effective interfacial area for all types of packings with different rotational speeds and gas–liquid ratios. An empirical correlation that takes the effects of the fiber diameter and opening size of the wire mesh into consideration was proposed for the calculation of the gas–liquid effective interfacial area of stainless steel wire mesh packings in a conventional RPB.

105 citations


Journal ArticleDOI
TL;DR: In this article, a packed bed breakthrough experiment was conducted for commercial zeolite 13X and 3-aminopropyl functionalized SBA-15 silica materials with three different amine loadings.
Abstract: Packed bed breakthrough experiments are reported for commercial zeolite 13X and 3-aminopropyl-functionalized SBA-15 silica materials with three different amine loadings. Mass and heat transfer dynamics for all four materials are modeled successfully. Amine adsorbents with open pores are found to exhibit faster mass diffusion rates compared to zeolite 13X. When amine loading is increased by coupling aminopropyl groups, premature breakthrough combined with a long tail is observed. Contrary to conventional physisorbants, finite heat losses to the column wall do not explain the long breakthrough tail. A rate model that accounts for heterogeneity in diffusion was found to accurately capture the breakthrough shape of the high loading material. Batch uptake measurements support the hypothesis that slow diffusion through the polymer phase is what hampers adsorption kinetics in the high amine loading adsorbent. The results emphasize the importance of designing materials that are not overloaded with amine sites, as...

102 citations


Journal ArticleDOI
TL;DR: In this article, the authors reported synthesis of Mn-ferrite using sol-gel technique, which involved the addition of Mn and Fe salts in ethanol followed by gelation using propylene oxide (PO).

Journal ArticleDOI
TL;DR: In this article, a comparative study of three different mathematical models for the packed bed latent heat storage system, comprised of a cylindrical storage tank filled with paraffin encapsulated spherical containers, is presented.

Journal ArticleDOI
TL;DR: In this paper, a primary amine functionalized polymeric ion exchange resin (Lewatit VP OC 1065, Lanxess) was evaluated for use in CO2 capture applications.
Abstract: A primary amine-functionalized polymeric ion-exchange resin (Lewatit VP OC 1065, Lanxess) was evaluated for use in CO2 capture applications. The polymeric resin was characterized by SEM, DRIFTS-IR, N2 adsorption isotherms, and packed bed sorption measurements to determine some of the characteristic properties of the resin. Capture capacities ranging from 1.85 to 1.15 mol CO2/kg sorbent were obtained in a packed bed reactor exposed to 10 vol % CO2 in N2 at adsorption temperatures ranging from 30 to 70 °C. The capture capacity of the resin was stable over 18 adsorption/regeneration cycles. The resin was evaluated through thermogravimetric analysis to have a low moisture adsorption (1.5 mol H2O/kg sorbent). It is possible to completely regenerate the resin under 1 atm of CO2 at 200 °C.

01 Jan 2012
TL;DR: In this article, the adsorption performance of packed bed column using activated carbon prepared from oil palm fibre (OPF) for the removal of lead (11) from aqueous solution was investigated.
Abstract: The adsorption performance of packed bed column using activated carbon prepared from oil palm fibre (OPF) for the removal of lead (11) from aqueous solution was investigated. The influence of important parameters like inlet ion concentration, flow rate and bed height on the breakthrough curves and adsorption performance was studied. The result indicated that adsorption efficiency increased with increase in the inlet ion concentration and bed height and decreased with increase in flow rate. Increasing the flow rate resulted to a shorter time for saturation. The result revealed that the throughput volume of the aqueous solution increased with increase in bed height, due to the availability of more number of sorption sites. The adsorption kinetics was analyzed using Thomas and Yoon and Nelson kinetic models. The kinetic data were well described by both models. The maximum adsorption capacity, calculated from both models, increased with increase in flow rate and initial ion concentration but decreased with increase in bed height. For Yoon and Nelson model, the rate constant increased with increase in flow rate, initial ion concentration and bed height. The time required for 50% breakthrough decreased with increase in flow rate, bed height and initial ion concentration. The kinetic data correlated well with both models. The comparison of the experimental breakthrough curve to the breakthrough profile obtained from Yoon and Nelson method showed a satisfactory fit for activated carbon derived from oil palm empty fruit bunch.

Journal ArticleDOI
TL;DR: In this work, oxidation with a Fenton-like process of a dye solution was carried out in a packed-bed reactor and it was found that the increase in temperature leads to a higher removal of the dye and an increased mineralization.

Journal ArticleDOI
TL;DR: In this paper, a dynamic pseudo-homogeneous model is presented to describe the operation of a packed bed reactor in which the SER reaction is carried out under adiabatic conditions, and it is demonstrated that the SER process can yield a CH 4 conversion and H 2 purity of up to 85% and 95%, respectively, under operating conditions of 923 K, 3.5 MPa, a steam/carbon ratio of 5 and a space velocity of 3.

Journal ArticleDOI
TL;DR: In this paper, effective interfacial area (ae) and liquid side mass transfer coefficient (kL) were investigated in a rotating packed bed (RPB) contactor with 5 novel rotors equipped with blades in the packing section and 1 conventional rotor without blades and fully filled with the same packing.
Abstract: In this work, gas–liquid mass transfer characteristics, such as effective interfacial area (ae) and liquid side mass transfer coefficient (kL), were investigated in a rotating packed bed (RPB) contactor with 5 novel rotors equipped with blades in the packing section and 1 conventional rotor without blades and fully filled with the same packing. The chemisorption of CO2 into a NaOH solution was used to evaluate ae and kL within each rotor of the RPB. The experimental results indicate that the rotors with blades can significantly intensify the mass transfer process at all rotational speeds, over a range of gas–liquid ratios. The mass transfer rate achieved within these novel rotors was between 8% and 68% higher in comparison with the conventional rotor. A model based on the Danckwerts surface renewal theory was developed to calculate the liquid side volumetric mass transfer coefficient (kLae) in the rotor. The experimentally obtained values of kLae are in agreement with model predictions within ±15%.

Journal ArticleDOI
TL;DR: In this paper, the effect of air mass flow rates and bed porosity on the thermal and thermohydraulic efficiencies of the counter and parallel flow packed bed solar air heaters are investigated theoretically and experimentally.

Journal ArticleDOI
TL;DR: In this paper, the mass transfer performance of CO2 absorption into aqueous diethylenetriamine (DETA) solutions was investigated in an absorption column randomly packed with Dixon rings at 303-303 K and atmospheric pressure, and compared with that of monoethanolamine (MEA), which is widely considered as a benchmark solvent for CO 2 absorption.
Abstract: The mass-transfer performance of CO2 absorption into aqueous diethylenetriamine (DETA) solutions was investigated in an absorption column randomly packed with Dixon rings at 303–303 K and atmospheric pressure, and compared with that of monoethanolamine (MEA), which is widely considered as a benchmark solvent for CO2 absorption. The mass-transfer performance was presented in terms of volumetric overall mass-transfer coefficient (KGav). In particular, the effects of operating parameters, such as inlet CO2 loading, solvent concentration, liquid flow rate, inert gas flow rate, and liquid temperature, were investigated and compared for both MEA and DETA. Over 40 runs of absorption experiments were carried out in this study. The results showed that KGav of DETA was found to be higher than that of MEA. Also, inlet CO2 loading, solvent concentration, liquid flow rate, and liquid inlet temperature had significant effect on KGav for both systems. However, the inert gas flow rate had an insignificant effect on KGav....

Journal ArticleDOI
TL;DR: In this article, the effects of temperature, gas flow rate, liquid flow rate and PZ content in solution on CO2 capture efficiency and dissolved oxygen (DO) in solution were studied by the 25 factorial design technique.

Journal ArticleDOI
TL;DR: In this paper, the performance of three metal-organic frameworks (MOFs): CuBTC, MIL-101, and Zn(bdc)dabco, with that of NaX zeolite for selective adsorption of CO 2 from mixtures containing CH 4 and CO in a pressure swing adaption (PSA) unit operating at pressures ranging to 60 bar.

Journal ArticleDOI
TL;DR: In this paper, a two-stage counter-current rotating packed bed (TSCC-RPB) was designed for and applied in continuous distillation, and the hydrodynamic characteristics of the TSCC-RBP including gas pressure drop and flooding performance were studied with air-water system and airglycerin solution system.
Abstract: A novel two-stage counter-current rotating packed bed (TSCC-RPB) was specially designed for and applied in continuous distillation. The hydrodynamic characteristics of the TSCC-RPB including gas pressure drop and flooding performance were studied with air–water system and air–glycerin solution system. The effects of rotational speed, gas flow rate, liquid flow rate and liquid viscosity on the pressure drop and flooding were examined. Continuous distillation experiments were carried out in the TSCC-RPB with an acetone–water system at atmospheric pressure. The separation efficiency is presented in terms of the number of theoretical plates (NT) and the effects of the operating parameters, such as rotational speed, feedstock temperature, feedstock concentration, and reflux ratio on the separation efficiency were investigated. Experimental results showed that the TSCC-RPB is an efficient gas–liquid contactor having a NT of 4.94–11.57 with a packing thickness of 200 mm.

Journal ArticleDOI
TL;DR: In this paper, the adsorption characteristics of zeolites with different framework structures and different exchanged cation species were examined with a view to using them as adsorbents for the dehydration of ethanol.

Journal ArticleDOI
TL;DR: In this paper, a conceptual adsorption process for the recovery and purification of biobutanol is proposed, where different porous materials are tested on their ability to perform the adsorptive separations relevant to the process.
Abstract: A conceptual adsorption process for the recovery and purification of biobutanol is proposed. Different porous materials are tested on their ability to perform the adsorptive separations relevant to the process. The metal-organic framework ZIF-8, silicalite zeolite and active carbon were compared with respect to their adsorption capacity of 1-butanol dissolved in water, as obtained in static and dynamic conditions by respectively batch and breakthrough measurements at room temperature. Batch experimentation showed that other compounds present in a real ABE fermentation have no significant effect on the adsorption of 1-butanol on ZIF-8. The breakthrough separation of 1-butanol from an aqueous ABE mixture was performed with a ZIF-8 packed column. The desorption of 1-butanol from a saturated ZIF-8 packed column by a stepwise increase of the temperature to 423 K in combination with a purge of a nitrogen gas (60 ml/min) shows that 1-butanol desorbs at low temperature from ZIF-8. Adsorption isotherms of ethanol, 1-butanol and water in liquid phase on the zeolite SAPO-34 were determined by batch adsorption at 298 K. Also the separation of an ethanol/1-butanol mixture and the removal of ethanol from 1-butanol could be achieved with a SAPO-34 packed column. From this experimental work, two materials—ZIF-8 and SAPO-34—thus emerged as suitable adsorbents for the recovery and purification of biobutanol by adsorption.

Journal ArticleDOI
TL;DR: In this paper, a novel heterogeneous catalyst for degradation of phenol has been synthesized, which was applied to a stirred batch reactor under mild conditions with 100mg L−1 initial phenol concentration and H2O2 as oxidant.

Journal ArticleDOI
TL;DR: The performance of a pilot scale packed differential contactor was evaluated for the continuous counter-current aqueous two-phase extraction of human immunoglobulin G (IgG) from a Chinese hamster ovary cells supernatant (CHO) enriched with pure protein.

Journal ArticleDOI
TL;DR: In this paper, a novel process concept for biogas treatment based on dynamically operated cryogenic packed beds (CPB) has been proposed and studied with numerical simulations, and the results reveal that the purity and recovery of CH4 are higher for the CPB concept, while also the bed capacity is much higher: the productivity (defined as kgCH4 h−1 mpacking 3) is a factor of 8 higher.
Abstract: A novel process concept for biogas treatment based on dynamically operated cryogenic packed beds (CPB) has been proposed and studied with numerical simulations. This work describes the CPB concept and investigates the different process steps involved with simulation results. To demonstrate the potential to treat biogas using the proposed process, the performance is compared to vacuum pressure swing adsorption (VPSA) on the basis of several criteria: purity and recovery of the obtained product, bed dimensions, and energy requirements. Simulation results reveal that the purity and recovery of CH4 are higher for the CPB concept, while also the bed capacity is much higher: the productivity (defined as kgCH4 h–1 mpacking–3) is a factor of 8 higher. The recovery is carried out with air and when operated in reversed flow mode, the novel CPB technology requires a 22% lower energy duty (2.9 MJ/kgCH4 vs 3.7 MJ/kgCH4 for the VPSA process). Furthermore, simultaneous deep H2S removal is possible using the proposed con...

Journal ArticleDOI
TL;DR: In this article, heat and mass transfer dynamics of CO2 adsorption onto a 3-aminopropylsilyl-functionalized SBA-15 silica material are reported.
Abstract: The packed bed heat and mass transfer dynamics of CO2 adsorption onto a 3-aminopropylsilyl-functionalized SBA-15 silica material are reported. Concentration measurements at the outlet of the packed bed and temperature profiles inside the bed are measured simultaneously. Heat and mass transfer models in conjunction with the linear driving force rate model are used to simulate the concentration and temperature profiles in the bed. The heat and mass transfer processes in the amine adsorbent packed bed are successfully captured by the model, and comparison of isothermal and nonisothermal models reveals that isothermal models provide an accurate description of the dynamic mass transport behavior in the adsorption column under the experimental conditions used in this study. The results help establish that under certain experimental conditions, heat effects in amine adsorbent packed beds have a negligible effect on CO2 breakthrough, and simple isothermal models can be used to accurately assess adsorption kinetics.

Journal ArticleDOI
TL;DR: In this article, a mixed amine solvent, Stonvent-II, was used for the absorption of approximately 75 vol% CO2 in CO2-NG stream at a pressure of 10 barg.

Journal ArticleDOI
TL;DR: In this article, a comprehensive and simplified rate-based mathematical model of a packed column for CO 2 capture using aqueous monoethanolamine (MEA) solution is developed, which takes into account the effect of kinetic reactions on the mass transfer, the thermodynamic nonidealities, the hydraulics of the random packing and the absorber dimensions (diameter and height).