The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Kevin P. Resnik - One of the best experts on this subject based on the ideXlab platform.
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CHARACTERIZATION OF NO2 AND SO2 REMOVALS IN A Spray Dryer/BAGHOUSE SYSTEM
Industrial & Engineering Chemistry Research, 1994Co-Authors: William J. O'dowd, Henry W. Pennline, Joanna M. Markussen, Kevin P. ResnikAbstract:Oxidation of NO to NO[sub 2] has been proposed as a method for enhancing NO[sub x] removals in conventional flue gas desulfurization (FGD) processes. This experimental investigation characterizes the removals of NO[sub 2] and SO[sub 2] in a 1.1 m[sup 3](standard)/min Spray Dryer/baghouse system. Flue gas was generated by burning a No. 2 fuel oil, which was subsequently spiked upstream of the Spray Dryer with NO[sub 2] or SO[sub 2] or both. Lime slurry was injected via a rotary atomizer into the Spray Dryer. Variables studied include the approach to the adiabatic saturation temperature, stoichiometric ratio, SO[sub 2] concentration, and NO[sub 2] concentration. Significant quantities of NO[sub 2] are scrubbed in this system, and over half of the total removal (at inlet NO[sub 2] > 400 ppm) occurs in the baghouse. Increasing NO[sub 2] concentrations enhance the amount of NO[sub x] removed in the system. Also, the presence of significant quantities of NO[sub 2] enhances the baghouse SO[sub 2] removal. Although up to 72% NO[sub 2] removals were obtained, concentrations of NO[sub 2] that exited the system were greater than 50 ppm for all conditions investigated.
J. Wang - One of the best experts on this subject based on the ideXlab platform.
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Heated Fly Ash/Hydrated Lime Slurries for SO2 Removal in Spray Dryer Absorbers
Industrial & Engineering Chemistry Research, 1995Co-Authors: John F. Sanders, Tim C. Keener, J. WangAbstract:Coal fly ashes have been slurried with quicklime at elevated temperatures to determine their reactivity with SO[sub 2] in a minipilot Spray Dryer. Bench-scale experimental results indicate that this hydration process greatly increases the total surface area of the solids. Minipilot-scale Spray Dryer tests reveal that the slurry reaction step can significantly increase calcium utilization and SO[sub 2] removal of these fly ash/quicklime sorbents, depending on the type of fly ash used. One type of fly ash showed considerably better reactivity in the Spray Dryer tests. This enhancement is considered due to the presence of calcium silica hydrate material formed from the reaction between calcium and the alumina silicate found in the fly ashes and the difference in reactivity due to the type of calcium silica hydrate material formed. The benefit, however, decreases with the calcium feed rate. Pozzolanic strength tests were performed on the fly ashes used, and the measured unconfined compressive strengths followed the reactivity results in the Spray Dryer; the most reactive fly ash possessed the highest pozzolanic activity.
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heated fly ash hydrated lime slurries for so2 removal in Spray Dryer absorbers
Industrial & Engineering Chemistry Research, 1995Co-Authors: John F. Sanders, Tim C. Keener, J. WangAbstract:Coal fly ashes have been slurried with quicklime at elevated temperatures to determine their reactivity with SO[sub 2] in a minipilot Spray Dryer. Bench-scale experimental results indicate that this hydration process greatly increases the total surface area of the solids. Minipilot-scale Spray Dryer tests reveal that the slurry reaction step can significantly increase calcium utilization and SO[sub 2] removal of these fly ash/quicklime sorbents, depending on the type of fly ash used. One type of fly ash showed considerably better reactivity in the Spray Dryer tests. This enhancement is considered due to the presence of calcium silica hydrate material formed from the reaction between calcium and the alumina silicate found in the fly ashes and the difference in reactivity due to the type of calcium silica hydrate material formed. The benefit, however, decreases with the calcium feed rate. Pozzolanic strength tests were performed on the fly ashes used, and the measured unconfined compressive strengths followed the reactivity results in the Spray Dryer; the most reactive fly ash possessed the highest pozzolanic activity.
Chiou-liang Lin - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous control of acid gases and PAHs using a Spray Dryer combined with a fabric filter using different additives.
Journal of hazardous materials, 2002Co-Authors: Zhen-shu Liu, M.-y. Wey, Chiou-liang LinAbstract:The purpose of this research was to simultaneously evaluate the removal efficiency of acid gases and PAHs from the flue gas emitted by a laboratory incinerator. This flue gas contained dust, acid gases, organics and heavy metals. A Spray Dryer combined with a fabric filter was used as the air pollution control device (APCD) in this study. The operating conditions investigated included different feedstock additives (polyvinyl chloride (PVC) and NaCl) and Spray Dryer additives (SiO2, CaCl2 and NaHCO3). The removal efficiency for SO2 could be enhanced by adding inorganic additives, such as SiO2, CaCl2 and NaHCO3. The presence of PVC in the incinerator feedstock also increased the removal efficiency of SO2in the Spray Dryer. The improved removal of PAHs could be attributed to the addition of feedstock additives (PVC and NaCl) and Spray Dryer additives (SiO2, CaCl2 and NaHCO3).
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The capture of heavy metals from incineration using a Spray Dryer integrated with a fabric filter using various additives.
Journal of the Air & Waste Management Association (1995), 2001Co-Authors: Zhen-shu Liu, M.-y. Wey, Chiou-liang LinAbstract:This study investigated the effects of feedstock additives [polyvinyl chloride (PVC) and NaCl] and Spray Dryer additives (SiO2, CaCl2, NaHCO3) on heavy metal and fly ash removal efficiencies, and on particle size distribution of heavy metals. A Spray Dryer with an integrated fabric filter was used as an air pollution control device (APCD). Removal efficiencies for fly ash and heavy metals were greater than 95 and 90%, respectively. When additives of PVC or NaCl were used, the concentration of heavy metals distributed in fly ash apparently varied when the particle diameter was 1 microm).
Fernanda De Melo Ramos - One of the best experts on this subject based on the ideXlab platform.
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Drying of Maltodextrin solution in a vacuum Spray Dryer
Chemical Engineering Research and Design, 2019Co-Authors: Fernanda De Melo Ramos, Vivaldo Silveira Junior, Job Ubbink, Ana Silvia PrataAbstract:Abstract New drying strategies that use low temperatures can have a significant impact on the improvement of food quality, in particular regarding the retention of flavor compounds, bioactives and other thermosensitive components. The vacuum Spray Dryer (VSD) is a Spray Dryer that operates with a low-pressure drying chamber, which consequently reduces the increases the thermodynamic driving force for water removal and allows drying at significantly reduced temperatures. In order to understand the process behavior and define operational strategies, a mathematical model that encompasses mass and energy balances was validated with experimental measurements of pressure and temperature during drying of large chained maltodextrin (dextrose equivalent = 10). Results from experiments carried out in a pilot VSD present a good fit with the proposed model and confirmed its underlying assumptions. In addition, comparative analyses were performed regarding physical aspects of particles produced by VSD and by conventional Spray Dryer (SD) in the same equipment, but without vacuum. Under the tested conditions, VSD particles presented a higher moisture content (8%) and smaller time of wettability than SD particles. The morphological changes were caused by the vacuum and can be interesting for technological applications.
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Assessment of differences between products obtained in conventional and vacuum Spray Dryer
Food Science and Technology, 2016Co-Authors: Fernanda De Melo Ramos, Cíntia Carla Melgaço De Oliveira, Ana Silvia Prata Soares, Vivaldo Silveira JuniorAbstract:In this work, an experimental unit of a vacuum Spray Dryer was built. This prototype attempted to combine the advantages of freeze-drying (drying at low temperatures due to vacuum) and Spray drying (increase of surface area aiming the improvement of heat transfer efficiency). Maltodextrin solutions were dried in the vacuum operated equipment and in conventional Spray Dryer. The vacuum Spray Dryer system allowed obtaining powder at low temperatures due to the lowering of pressure conditions (2-5 kPa) inside the drying chamber. The products obtained in the two systems were characterized and compared for particle size distribution, moisture content, water activity, bulk density and solubility in water. The processes yields were also evaluated and compared. The vacuum Spray Dryer system allowed the production of larger, more soluble and less dense particles than those obtained in the conventional configuration of the equipment, resulting in drier and, therefore, with lower water activity particles. Thus, the use of the vacuum Spray Dryer as a drying technique may be an alternative for the production of powder rich in thermosensitive compounds.
Ana Silvia Prata - One of the best experts on this subject based on the ideXlab platform.
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Drying of Maltodextrin solution in a vacuum Spray Dryer
Chemical Engineering Research and Design, 2019Co-Authors: Fernanda De Melo Ramos, Vivaldo Silveira Junior, Job Ubbink, Ana Silvia PrataAbstract:Abstract New drying strategies that use low temperatures can have a significant impact on the improvement of food quality, in particular regarding the retention of flavor compounds, bioactives and other thermosensitive components. The vacuum Spray Dryer (VSD) is a Spray Dryer that operates with a low-pressure drying chamber, which consequently reduces the increases the thermodynamic driving force for water removal and allows drying at significantly reduced temperatures. In order to understand the process behavior and define operational strategies, a mathematical model that encompasses mass and energy balances was validated with experimental measurements of pressure and temperature during drying of large chained maltodextrin (dextrose equivalent = 10). Results from experiments carried out in a pilot VSD present a good fit with the proposed model and confirmed its underlying assumptions. In addition, comparative analyses were performed regarding physical aspects of particles produced by VSD and by conventional Spray Dryer (SD) in the same equipment, but without vacuum. Under the tested conditions, VSD particles presented a higher moisture content (8%) and smaller time of wettability than SD particles. The morphological changes were caused by the vacuum and can be interesting for technological applications.
