Study on Spray Evaporation Treatment of Desulfurization Wastewater

Limestone-gypsum wet flue gas desulfurization (WFGD) often produces a certain amount of wastewater with complex water quality and heavy metal pollution which should be treated properly before release. Spaying the desulfurization wastewater into flue duct and using exhausted flue gas heat for evaporation is a promising and economical technology for achieving zero wastewater discharge in thermal power plant. To enable a more in-depth understanding on evaporation of FGD wastewater spray, a visual wind tunnel test rig based on the atomized droplet laser measuring system was built to reveal the impact factors on droplet thermal-fluid behavior. The dominant impact factors such as compressed air pressure and flow rate in air-blast spray nozzle, hot air temperature and velocity in the evaporation tunnel were analyzed to discuss the droplet size distribution and evaporation performance through alternating operate condition. A discrete mathematical model that combines both Eulerian and Lagrangian framework was established to validate the experiment result. It is concluded that introducing high pressure compressed air into the nozzle can contribute to the dispersion of droplets and enhance the evaporation rate. Proper flow rate in spray nozzle is required to avoid incomplete droplets evaporation. Air temperature and velocity in the evaporation tunnel apply positive impact on droplet size distribution and evaporation performance. Numerical simulation results of both dominant factors impact on evaporation behavior and total evaporation rate showed consistency with the experimental outcome.

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Application of a Fiber Optic Probe to High Void Fraction Air/Water Flow

Volume 2: Fora ◽

10.1115/fedsm2008-55043 ◽

2008 ◽

Author(s):

A. J. Pertzborn ◽

W. C. Smith

Keyword(s):

Size Distribution ◽

Water Flow ◽

Void Fraction ◽

Droplet Size ◽

Fiber Optic ◽

Droplet Size Distribution ◽

Spray Nozzle ◽

Fiber Optic Probe ◽

Flow Measurements ◽

Optic Probe

Successful development of CFD models for droplet flows is aided by knowledge of the droplet size distribution in the flow, but current instrumentation for measuring droplet size is limited. In an attempt to improve the quality of data collected, fiber optic probe (FOP) technology was investigated. A spray nozzle injected water droplets into an air stream to create a high void fraction droplet flow. Measurements were acquired with the spray nozzle at two different locations upstream of the FOP position. Mean droplet velocity measurements were acquired using laser Doppler velocimetry (LDV) at the FOP position. The droplet size distribution at the probe location was determined by using both the FOP and LDV measurements. The initial results indicate that FOP technology can successfully measure the droplet size distribution in a high void fraction air/water flow and it should be further developed for this application.

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Experimental Study of Droplet Size Distribution Produced by a Multi-Orifice Effervescent Atomizer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.3056 ◽

2012 ◽

Vol 166-169 ◽

pp. 3056-3059 ◽

Cited By ~ 2

Author(s):

Fang Xu ◽

Wei Dong ◽

Liang Qiang

Keyword(s):

Experimental Study ◽

Size Distribution ◽

Droplet Size ◽

Flow Rate ◽

Water Flow Rate ◽

Injection Pressure ◽

Droplet Size Distribution ◽

Liquid Injection ◽

Effervescent Atomizer ◽

Pressure Water

A new multi-orifice effervescent atomizer used for fire fighting was developed. The droplet size distribution of the spray produced by the nozzle was measured by laser Doppler particle analyzer. And the influence of liquid injection pressure, water flow rate and atomizer internal geometry was studied.

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Analysis of Environmental Impact Factors of Natural Draft Cooling Towers in Power Plant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.1436 ◽

2013 ◽

Vol 726-731 ◽

pp. 1436-1440 ◽

Cited By ~ 1

Author(s):

Feng Ding ◽

Xin Bo

Keyword(s):

Environmental Impact ◽

Water Content ◽

Flow Rate ◽

Liquid Water ◽

Flue Gas ◽

Gas Flow ◽

Cooling Tower ◽

Liquid Water Content ◽

Impact Factors ◽

Gas Flow Rate

Based on the requirements of Air Clean guidelines (VDI3784 and VDI3945) in German for cooling tower plume rise and dispersion model, a comparative analysis of atmospheric environmental impact of the cooling tower exhaust for different parameters. Parameters includes different source emission parameters and ambient humidity parameters. Then, analysis of the impact factors of plume rising height and the ground concentration according to the emission parameters. The results show that the most influential parameters are temperature and gas flow rate, relatively, the flue gas relative humidity and liquid water content has less influence in the rising height. Therefore, the increase of flue gas flow rate will significantly strengthen the dispersion of pollutants in the air. The flue gas humidity and liquid water have a certain influence on the dispersion of pollutants, but the effect is not so significant. The increase of flue gas humidity and liquid water content is not conducive to the dispersion of pollutants, therefore the surface concentration will only increase slightly.

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Effect of Process Parameters on Characteristics of Spray-Dried Hydroxyapatite Granules

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.728.341 ◽

2017 ◽

Vol 728 ◽

pp. 341-346 ◽

Cited By ~ 3

Author(s):

Weeranuch Sukaraseranee ◽

Sukasem Watcharamaisakul ◽

Boris Golman ◽

Jintamai Suwanprateeb

Keyword(s):

Size Distribution ◽

Air Temperature ◽

Flow Rate ◽

Feed Rate ◽

Air Flow ◽

Spherical Shape ◽

Air Flow Rate ◽

Uniform Size ◽

Drying Conditions ◽

Spray Dried

The effects of drying air temperature and flow rate, spraying air flow rate and slurry feed rate were investigated on the morphology, size distribution, density and flowability of spray-dried hydroxyapatite granules. The granules were of good spherical shape and smooth surface, but low flowability. The granules of uniform size distribution were obtained at high spraying air flow rate and granules of small sizes were collected at high spraying and drying air flow rates, high slurry feed rate and low drying air temperature. Thus, by adjusting the spray drying conditions we can control the granule properties.

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Influence of Semicontinuous Processing on the Rheology and Droplet Size Distribution of Mayonnaise-like Emulsions

Food Science and Technology International ◽

10.1177/1082013209345046 ◽

2009 ◽

Vol 15 (4) ◽

pp. 367-373 ◽

Cited By ~ 7

Author(s):

C. Bengoechea ◽

M.L. López ◽

F. Cordobés ◽

A. Guerrero

Keyword(s):

Size Distribution ◽

Droplet Size ◽

Flow Rate ◽

Droplet Size Distribution ◽

Egg Yolk ◽

Continuous Phase ◽

Agitation Speed ◽

Viscosity Data ◽

Pumping System ◽

Oil In Water

Oil-in-water (o/w) emulsions stabilized by egg yolk, with a composition similar to those found in commercial mayonnaises or salad dressings, were processed in a semicontinuous device. This specially designed emulsification device consists of, basically, a vessel provided with an anchor impeller, where the continuous phase was initially placed; a pumping system that controls the addition of the oily phase; a rotor-stator unit, where the major breaking of the oily droplets takes place, and a recirculation system. The design allowed the introduction of a rotational rheometer to obtain viscosity data along the emulsification process. The most important advantages of this in-line emulsification device, when compared to discontinuous emulsification equipment, are the possibilities of recording viscosity data along the process and the higher values for the storage, G', and loss moduli, G'', of the resulting emulsions. The influence of egg yolk concentration, agitation speed, and flow rate over the rheological properties (G', G'') as well as droplet size distribution were investigated. Higher protein concentration, agitation speed and flow rate generally produce emulsions with higher G' and G'' values.

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Droplet Formation Through Centrifugal Pumps for Oil-in-Water Dispersions

SPE Journal ◽

10.2118/163055-pa ◽

2012 ◽

Vol 18 (01) ◽

pp. 172-178 ◽

Cited By ~ 10

Author(s):

Rosanel Morales ◽

Eduardo Pereyra ◽

Shoubo Wang ◽

Ovadia Shoham

Keyword(s):

Size Distribution ◽

Centrifugal Pump ◽

Droplet Size ◽

Flow Rate ◽

Droplet Size Distribution ◽

Droplet Formation ◽

Centrifugal Pumps ◽

Mixture Flow ◽

Pump Speed ◽

Water Cut

Summary Droplet formation in oil/water flow through a centrifugal pump has been studied, experimentally and theoretically, for the first time. Droplet-size distribution at the pump outlet has been measured for water-continuous flow as a function of pump speed, mixture-flow rate, and water cut. The measured droplet-size distribution strongly depends on the pump speed: the higher the pump speed, the smaller the droplet size. Negligible effects of mixture-flow rate, water cut, and inlet droplet-size distribution have been observed. Turbulent breakup has been identified as the main mechanism for droplet formation. A mechanistic model is developed for the prediction of droplet-size distribution in a centrifugal pump, showing a fair agreement with the acquired experimental data.

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Influence of Operating Parameters on Physicochemical Properties of Fruit Juice Powders Produced by Spray Drying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.941-944.1196 ◽

2014 ◽

Vol 941-944 ◽

pp. 1196-1200

Author(s):

Li Li Zhang ◽

Chuan Chuan Ma

Keyword(s):

Moisture Content ◽

Physicochemical Properties ◽

Bulk Density ◽

Air Temperature ◽

Flow Rate ◽

Fruit Juice ◽

Air Flow ◽

Compressed Air ◽

Operating Parameters ◽

Air Flow Rate

This paper investigated the influence of operating parameters such as inlet air temperature, compressed air flow rate, concentration of carrier agent and type of carrier on the physicochemical properties of fruit juice powders produced by spray drying.The results indicated that increasing inlet air temperature resulted in the larger size particles with smoothly spherical appearance, and to lower bulk density and moisture content. The bulk density of powders also decreased with increasing carrier agent concentration, decreasing compressed air flow rate. The higher feed flow rate negatively affected process yield and positively influenced moisture content, and occurring the wall deposition easily. Additionally, the anthocyanin retention mainly depends on the inlet air temperature and type of carrier. Moreover, the novel methods and ideas to this problem in the next studies were presented.

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Numerical Investigation on the Evaporation Performance of Desulfurization Wastewater in a Spray Drying Tower without Deflectors

Coatings ◽

10.3390/coatings11091022 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1022

Author(s):

Debo Li ◽

Ning Zhao ◽

Yongxin Feng ◽

Zhiwen Xie

Keyword(s):

Spray Drying ◽

Droplet Size ◽

Flow Rate ◽

Flue Gas ◽

Gas Flow ◽

Initial Temperature ◽

Gas Temperature ◽

Gas Flow Rate ◽

Complete Evaporation ◽

Desulfurization Wastewater

The desulfurization wastewater evaporation technology with flue gas has been widely applied to dispose of desulfurization wastewater. This paper investigates the effect of flue gas flow rate and temperature, wastewater flow rate and initial temperature, and droplet size on the evaporation performance of the desulfurization wastewater in a spray drying tower without deflectors. The results show that the flue gas flow rate and temperature affect the evaporation performance of desulfurization wastewater. The larger flow rate and higher temperature of flue gas correspond to the faster evaporation speed and the shorter complete evaporation distance of the wastewater droplet. Decreasing the flow rate and increasing the initial temperature of the desulfurization wastewater is advantageous to enhance the evaporation speed and shorten the complete evaporation distance of the wastewater droplet. Reducing the droplet size is beneficial to improve the evaporation performance of the desulfurization wastewater. The orthogonal test results show that the factors affecting droplet evaporation performance are ranked as follows: flue gas flow rate > wastewater flow rate > flue gas temperature > wastewater initial temperature > droplet size. Considering the evaporation ratio and the complete evaporation distance, the optimal setting is 14.470 kg/s for flue gas flow rate, 385 °C for flue gas temperature, 0.582 kg/s for wastewater flow rate, 25 °C for wastewater initial temperature, and 60 μm for droplet size. These studied results can provide valuable information to improve the operational performance of the desulfurization wastewater evaporation technology with flue gas.

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