The Experts below are selected from a list of 13380 Experts worldwide ranked by ideXlab platform
Pierrefrancois Iard - One of the best experts on this subject based on the ideXlab platform.
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intensification of volatile organic compound absorption in a compact Wet Scrubber at co current flow
Chemosphere, 2017Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe RenneAbstract:Three volatile organic compounds (VOC) with no acidic or basic function (butanol, butyraldehyde, methylethylketone), encountered at low concentrations in odorous effluents, were absorbed in water in a compact Wet Scrubber. This gas-liquid contactor consisted of a wire mesh packing structure where the gas phase flows at high velocity (>12 m s-1). A very turbulent two-phase downward flow could be observed in the Scrubber with dispersed fine droplets (around 10 μm). For compounds showing a good affinity for water, such as butanol, removal efficiencies up to 90% were measured for a short contactor length of 32 cm leading to a gas residence time of 20 ms. However, the removal efficiency of butyraldehyde, which is poorly soluble in water, ranged between 10 and 30%. Mass-transfer modeling was achieved and underlined that working with several small Scrubbers in series, fed with an unloaded solution, is effective to improve the removal efficiency. The influences of the VOC/solvent affinity, the contactor length, and the mass-transfer and hydrodynamic parameters on the removal efficiency were evaluated through a sensitivity analysis.
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assessment and optimisation of voc mass transfer enhancement by advanced oxidation process in a compact Wet Scrubber
Chemosphere, 2009Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe Renne, Jeanpierre LevasseuAbstract:Abstract Dimethyl disulphide (DMDS) removal was investigated in a compact Scrubber (hydraulic residence time ≈20 ms), composed of a wire mesh packing structure where liquid and gas flow at co-current and high gas superficial velocity (>12 m s−1). In order to regenerate the scrubbing liquid and to maintain a driving force in the Scrubber, ozone and hydrogen peroxide were added to water since they allow the generation of nonselective and highly reactive species, hydroxyl radicals HO . Three ways of reagent distribution were tested. The influence of several parameters (liquid flow rate(s), ozone flow rate, pH and reagent concentrations) was investigated. The best configuration was obtained when ozone is transferred in the scrubbing liquid before introduction at the top of the Scrubber simultaneously with the hydrogen peroxide solution, allowing to generate hydroxyl radical in the Scrubber. With this configuration, DMDS removal could be increased from 16% with water to 34% at the same gas and liquid flow rates in the Scrubber showing the potentiality of advanced oxidation process.
Christophe Renne - One of the best experts on this subject based on the ideXlab platform.
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intensification of volatile organic compound absorption in a compact Wet Scrubber at co current flow
Chemosphere, 2017Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe RenneAbstract:Three volatile organic compounds (VOC) with no acidic or basic function (butanol, butyraldehyde, methylethylketone), encountered at low concentrations in odorous effluents, were absorbed in water in a compact Wet Scrubber. This gas-liquid contactor consisted of a wire mesh packing structure where the gas phase flows at high velocity (>12 m s-1). A very turbulent two-phase downward flow could be observed in the Scrubber with dispersed fine droplets (around 10 μm). For compounds showing a good affinity for water, such as butanol, removal efficiencies up to 90% were measured for a short contactor length of 32 cm leading to a gas residence time of 20 ms. However, the removal efficiency of butyraldehyde, which is poorly soluble in water, ranged between 10 and 30%. Mass-transfer modeling was achieved and underlined that working with several small Scrubbers in series, fed with an unloaded solution, is effective to improve the removal efficiency. The influences of the VOC/solvent affinity, the contactor length, and the mass-transfer and hydrodynamic parameters on the removal efficiency were evaluated through a sensitivity analysis.
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assessment and optimisation of voc mass transfer enhancement by advanced oxidation process in a compact Wet Scrubber
Chemosphere, 2009Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe Renne, Jeanpierre LevasseuAbstract:Abstract Dimethyl disulphide (DMDS) removal was investigated in a compact Scrubber (hydraulic residence time ≈20 ms), composed of a wire mesh packing structure where liquid and gas flow at co-current and high gas superficial velocity (>12 m s−1). In order to regenerate the scrubbing liquid and to maintain a driving force in the Scrubber, ozone and hydrogen peroxide were added to water since they allow the generation of nonselective and highly reactive species, hydroxyl radicals HO . Three ways of reagent distribution were tested. The influence of several parameters (liquid flow rate(s), ozone flow rate, pH and reagent concentrations) was investigated. The best configuration was obtained when ozone is transferred in the scrubbing liquid before introduction at the top of the Scrubber simultaneously with the hydrogen peroxide solution, allowing to generate hydroxyl radical in the Scrubber. With this configuration, DMDS removal could be increased from 16% with water to 34% at the same gas and liquid flow rates in the Scrubber showing the potentiality of advanced oxidation process.
Annabelle Couve - One of the best experts on this subject based on the ideXlab platform.
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intensification of volatile organic compound absorption in a compact Wet Scrubber at co current flow
Chemosphere, 2017Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe RenneAbstract:Three volatile organic compounds (VOC) with no acidic or basic function (butanol, butyraldehyde, methylethylketone), encountered at low concentrations in odorous effluents, were absorbed in water in a compact Wet Scrubber. This gas-liquid contactor consisted of a wire mesh packing structure where the gas phase flows at high velocity (>12 m s-1). A very turbulent two-phase downward flow could be observed in the Scrubber with dispersed fine droplets (around 10 μm). For compounds showing a good affinity for water, such as butanol, removal efficiencies up to 90% were measured for a short contactor length of 32 cm leading to a gas residence time of 20 ms. However, the removal efficiency of butyraldehyde, which is poorly soluble in water, ranged between 10 and 30%. Mass-transfer modeling was achieved and underlined that working with several small Scrubbers in series, fed with an unloaded solution, is effective to improve the removal efficiency. The influences of the VOC/solvent affinity, the contactor length, and the mass-transfer and hydrodynamic parameters on the removal efficiency were evaluated through a sensitivity analysis.
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assessment and optimisation of voc mass transfer enhancement by advanced oxidation process in a compact Wet Scrubber
Chemosphere, 2009Co-Authors: Pierrefrancois Iard, Annabelle Couve, Christophe Renne, Jeanpierre LevasseuAbstract:Abstract Dimethyl disulphide (DMDS) removal was investigated in a compact Scrubber (hydraulic residence time ≈20 ms), composed of a wire mesh packing structure where liquid and gas flow at co-current and high gas superficial velocity (>12 m s−1). In order to regenerate the scrubbing liquid and to maintain a driving force in the Scrubber, ozone and hydrogen peroxide were added to water since they allow the generation of nonselective and highly reactive species, hydroxyl radicals HO . Three ways of reagent distribution were tested. The influence of several parameters (liquid flow rate(s), ozone flow rate, pH and reagent concentrations) was investigated. The best configuration was obtained when ozone is transferred in the scrubbing liquid before introduction at the top of the Scrubber simultaneously with the hydrogen peroxide solution, allowing to generate hydroxyl radical in the Scrubber. With this configuration, DMDS removal could be increased from 16% with water to 34% at the same gas and liquid flow rates in the Scrubber showing the potentiality of advanced oxidation process.
Dennis Y C Leung - One of the best experts on this subject based on the ideXlab platform.
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Wet Scrubber coupled with heterogeneous uv fenton for enhanced vocs oxidation over fe zsm 5 catalyst
Chemosphere, 2019Co-Authors: Ruijie Xie, Gaoyua Liu, Dingping Liu, Shimi Liang, Dongxue Lei, Hanying Dong, Haibao Huang, Dennis Y C LeungAbstract:The traditional treatment processes for volatile organic compounds (VOCs) removal generally suffered several disadvantages, such as secondary air-pollutants. To overcome these issues, Wet Scrubber coupled with heterogeneous UV/Fenton was developed for gaseous VOCs (i.e. toluene) removal. ZSM-5 supported iron oxide (Fe/ZSM-5) was prepared as a multifunctional catalyst for activation of H2O2 and enhancement of gas-liquid mass transfer. Toluene was removed efficiently by this coupled process with the removal efficiency of 85% during 120 min. Many intermediates were detected in the solution by GC-MS while no intermediates were observed in the outlet gas, suggesting that Wet Scrubber coupled with heterogeneous UV/Fenton could significantly reduce secondary air pollutants. The possible mechanism of toluene oxidation was proposed including the physical adsorption by Fe/ZSM-5 and OH oxidation. This study provides an environmentally benign and highly efficient chemical scrubbing process for gaseous VOCs removal.
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Wet Scrubber coupled with uv pms process for efficient removal of gaseous vocs roles of sulfate and hydroxyl radicals
Chemical Engineering Journal, 2019Co-Authors: Ruijie Xie, Dongxue Lei, Dennis Y C Leung, Kaiheng Guo, Haibao HuangAbstract:Abstract In this study, Wet Scrubber coupled with UV/peroxymonosulfate (PMS) was used as a semi-batch process for removing gaseous VOCs. Both ethyl acetate and toluene could be removed efficiently using this coupled process due to the generation of SO4 − and HO . The mass-transfer coefficients in this coupled process were larger than in Wet scrubbing only process. The roles of SO4 − and HO were investigated, in which SO4 − acted as the predominant radical for toluene degradation while HO was major for ethyl acetate. This could be further confirmed by simultaneous degradation of ethyl and toluene. Moreover, the reaction solution reused at least four times still showed excellent performance for VOCs removal via re-adding PMS. A possible mechanism on toluene degradation was proposed based on the evolutions of intermediates during the process. This study clarified the roles of non-selective radical (i.e. HO ) and selective radical (i.e. SO4 − and Cl ) in the removal of a continuous-flow gaseous VOCs by this coupled process.
Flore Plaza - One of the best experts on this subject based on the ideXlab platform.
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numerical prediction of dust capture efficiency of a centrifugal Wet Scrubber
Aiche Journal, 2018Co-Authors: Hassa Ali, Flore PlazaAbstract:The gas, liquid, and dust particle behavior inside a centrifugal Wet Scrubber was simulated and a submodel for predicting its collection efficiency was developed that also takes in account the reduction in collection efficiency due to droplet carryover. Centrifugal Wet Scrubbers are used in many industries and deliver a high scrubbing efficiency at relatively low capital and operational costs. However, they often experience problems such as droplet carryover at high gas flows and reduced collection efficiency at low gas flows. An improved understanding of flow processes inside the Scrubbers is needed to develop a better Scrubber design. An experimental test facility was setup for this purpose which also served to validate the CFD modeling results. Ideal operating parameters for maximum scrubbing efficiency and minimum droplet carryover were identified.
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flow visualization and modelling of scrubbing liquid flow patterns inside a centrifugal Wet Scrubber for improved design
Chemical Engineering Science, 2017Co-Authors: Hassa Ali, Flore PlazaAbstract:This paper presents an experimental and computational study of flow aspects in a commonly used centrifugal Wet Scrubber design. While manufacturers advertise up to 99.9% collection efficiency for dust particles >10 µm in diameter, operators complain of compromised efficiency at low loads and droplet carryover at high loads. Similar problems are also faced by flue gas desulphurization towers. The industry requires satisfactory Scrubber performance at varying factory conditions. Different Scrubber flow parameters and dimensions were studied to discover the cause of the reported problems. Together with the CFD findings, the project delivered an improved understanding of the scrubbing liquid flow pattern which is crucial for high performance and was used as a basis to carry out design improvements.
