Application of Ceramic Membrane Technology in Tungsten Fine Particle Concentration Process

2014 ◽  
Vol 692 ◽  
pp. 191-199
Author(s):  
Wan Fu Huang ◽  
Xiao Feng Wang ◽  
Xin Dong Li ◽  
Si Ming Yan
Keyword(s):  
Fine Particle ◽  
Particle Concentration ◽  
Fine Particles ◽  
Ceramic Membrane ◽  
Membrane Technology ◽  
Factors Affecting ◽  
Membrane Flux ◽  
Concentration Test ◽  
Optimal Effect ◽  
Membrane Concentration

This study used ceramic membrane technology to concentrate tungsten fine particles for its inefficient recycling issue. Factors affecting the membrane concentration test were discussed, and the results show that: under the feed flow of 7000 mL/min, concentration time of 3 hours, and concentration liquid flow of 500 mL/min, it is the optimal effect of ceramic membrane concentration tungsten fine particle, which the interception rate reaches more than 99%, the membrane permeation flux can be nearly reach 470mL/(min×1099cm2) above, and concentrate concentration can be basically stable at around 29% . Ceramic membrane flux recovery rate can be as high as 93% by 7 minutes backwashing firstly and then 2 minutes forward cleaning.

A Novel System for Fine Particle Concentration Measurement

2014 ◽  
Vol 901 ◽  
pp. 29-33
Author(s):  
Ming Ru Guo ◽  
Wen Zhong Lou ◽  
Li Na Ren ◽  
Yu Fei Lu
Keyword(s):  
Fine Particle ◽  
Particle Concentration ◽  
Fine Particles ◽  
Ultrasonic Attenuation ◽  
Ultrasonic Transducer ◽  
Dust Cloud ◽  
Measuring System ◽  
The Novel ◽  
The Public ◽  
Measuring Devices

It is important to monitoring the fine particles (PM2.5) in atmosphere as it threatens the public health all over the world. But the existing concentration measuring devices have shortcomings in speed and range. A novel fine particle concentration measuring system based on the ultrasonic attenuation was designed in this paper, which could help to solve the problem. Firstly the mechanism of ultrasonic attenuation in dust cloud was studied to verify the relationship between the concentration and the ultrasonic attenuation. Then the novel concentration measuring system was designed. The micro ultrasonic transducer array was introduced into the system, so the system can be sensitive as well as small. Finally, experiment was conducted to check the performance of this measuring system, and the results show that it could realize measurement quickly.

scholarly journals Trends in Fine Particle Concentration and Chemical Composition in Southern California

2000 ◽  
Vol 50 (1) ◽  
pp. 43-53 ◽  
Author(s):  
Christos S. Christoforou ◽  
Lynn G. Salmon ◽  
Michael P. Hannigan ◽  
Paul A. Solomon ◽  
Glen R. Cass
Keyword(s):  
Chemical Composition ◽  
Fine Particle ◽  
Southern California ◽  
Particle Concentration

scholarly journals Enhancing main fermentation velocities in beer by the use of a membrane bioreactor – approach and preliminary results (membrane bioreactor beer)

2018 ◽  
Vol 14 (s1) ◽  
pp. 121-131 ◽  
Author(s):  
Lisa Stumpf ◽  
Stefan Schildbach
Keyword(s):  
Membrane Bioreactor ◽  
Membrane Technology ◽  
Gas Jet ◽  
Fermentation Processes ◽  
Preliminary Results ◽  
Module Design ◽  
Continuous Basis ◽  
Membrane Flux ◽  
High Level ◽  
Over Time

The potential of the most recent membrane technology is still unaccounted for in many respects. Combining fermentation with up-to-date membrane technology building a membrane bioreactor allows the adjustment of the cell count on a high level, increasing yield per volume and time. Applied to beer manufacturing, main fermentation times of less than 20 h seem possible, avoiding the disadvantages of already known accelerated fermentation processes operated on a continuous basis. Although module design was adapted and backwash procedure altered to gas-jet, maintaining a sufficient membrane flux over time still poses a major problem. Nevertheless, preliminary results in respect of beer quality look promising.

scholarly journals Study of pressurised metered dose inhalers for the purpose of standardization of quality attributes characterizing uniformity of dosing

2021 ◽  
pp. 11-23
Author(s):  
Elena Bezuglaya ◽  
Nikolay Lyapunov ◽  
Vladimir Bovtenko ◽  
Igor Zinchenko ◽  
Yurij Stolper
Keyword(s):  
Particle Size ◽  
Fine Particle ◽  
Fine Particles ◽  
Average Dose ◽  
Metered Dose Inhalers ◽  
Fine Particle Dose ◽  
Particle Dose ◽  
Metered Dose ◽  
Delivered Dose

Aim. The purpose was to provide the rationale of test in regard to uniformity of fine particles dose for pressurised metered dose inhalers (pMDIs). Materials and methods. The pMDIs containing suspensions of salbutamol sulfate (SS) or solutions of beclometasone dipropionate (BD) were studied by laser diffraction and high performance liquid chromatography (HPLC). The particle size distribution of SS, the average dose mass and uniformity of dose mass, the average delivered dose and the uniformity of delivered dose, the average fine particles dose and uniformity of fine particles dose were determined. Apparatus A was used for assessment of fine particles dose. Results. The two analytical procedures for the quantitative determination of SS and BD by HPLC were validated in the ranges with low concentrations of these substances. The 5 medicinal products in pMDI dosage form were studied: 3 preparations were with SS and 2 ones contained BD. It was shown that three products with SS were very similar in regard to particle size distribution in containers and the average values of delivered dose were almost the same, but these products were different in the average dose mass and fine particle dose. According to the research results, the expediency of determining the average dose mass and the tests concerning uniformity of dosing of preparations by dose mass and by fine particle dose was substantiated. It was shown that in the case of pMDI the dosing of solutions of BD was more uniform compared to suspensions of SS. The approaches of leading and other pharmacopoeias concerning uniformity of dosing for pMDIs were critically discussed. The expediency of determination of uniformity of fine particle dose at the stage of pharmaceutical development was substantiated, as the therapeutic effect depends on fine particle dose. Issues concerning standardization pMDIs in regard to uniformity of fine particle dose were discussed. Conclusions. The expediency of standardization and quality control of pMDIs in regard to such attributes as the average dose mass, which characterizes the volume of the metering chamber of the valve as well as the uniformity of the dose mass and the uniformity of fine particle dose, which assure the therapeutic effect of each dose of the product was substantiated

scholarly journals Atmospheric oxidation capacity in Chinese megacities during photochemical polluted season: radical budget and secondary pollutants formation

2018 ◽  
Author(s):  
Zhaofeng Tan ◽  
Keding Lu ◽  
Meiqing Jiang ◽  
Rong Su ◽  
Hongli Wang ◽  
...  
Keyword(s):  
Fine Particle ◽  
Fine Particles ◽  
Nox Reduction ◽  
Ozone Production ◽  
Atmospheric Oxidation ◽  
Ozone Pollution ◽  
Oxidation Capacity ◽  
Radical Chemistry ◽  
Budget Analysis ◽  
Secondary Pollutants

Abstract. Atmospheric oxidation capacity is the core of converting fresh-emitted substances to secondary pollutants. In this study, we present the in-situ measurements at four Chinese megacities (Beijing, Shanghai, Guangzhou, and Chongqing) in China during photochemical polluted seasons. The atmospheric oxidation capacity is evaluated using an observational-based model with the input of radical chemistry precursor measurements. The radical budget analysis illustrates the importance of HONO and HCHO photolysis, which contribute nearly half of the total radical primary sources. The radical propagation is efficient due to abundant of NO in the urban environments. Hence, the production rate of secondary pollutants, i.e. ozone and fine particle precursors (H2SO4, HNO3, and ELVOCs) is fast resulting in secondary air pollution. The ozone budget demonstrates that strong ozone production occurs in the urban area which results in fast ozone concentration increase locally and further transported to downwind areas. On the other hand, the O3-NOx-VOC sensitivity tests show that ozone production is VOC-limited, among which alkenes and aromatics should be first mitigated for ozone pollution control in the presented four megacities. However, NOx emission control will lead to more server ozone pollution due to the drawback-effect of NOx reduction. For fine particle pollution, the role of HNO3−NO3− partitioning system is investigated with a thermal dynamic model (ISORROPIA2) due to the importance of particulate nitrate during photochemical polluted seasons. The strong nitrate acid production converts efficiently to nitrate particles due to high RH and ammonium-rich conditions during photochemical polluted seasons. This study highlights the efficient radical chemistry maintains the atmospheric oxidation capacity in Chinese megacities, which results in secondary pollutions characterized by ozone and fine particles.

New Trends for Wastewater Treatment and Their Reuse Using Ceramic Membrane Technology: A Case Study

2018 ◽  
pp. 339-348 ◽  
Author(s):  
Swachchha Majumdar ◽  
Subhendu Sarkar ◽  
Sourja Ghosh ◽  
Priyankari Bhattacharya ◽  
Sibdas Bandyopadhyay ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Ceramic Membrane ◽  
Membrane Technology

scholarly journals Changes in Particle Size Composition under Seepage Conditions of Reclaimed Soil in Xinjiang, China

Processes ◽  
2018 ◽  
Vol 6 (10) ◽  
pp. 201 ◽  
Author(s):  
Zizhao Zhang ◽  
Wanghua Sui ◽  
Kaikai Wang ◽  
Guobin Tang ◽  
Xiaoping Li
Keyword(s):  
Particle Size ◽  
Fine Particle ◽  
Granulometric Composition ◽  
Fine Particles ◽  
Land Reclamation ◽  
Sharp Decrease ◽  
Size Composition ◽  
Particle Content ◽  
Reclaimed Soil ◽  
Different Depths

The distribution of reclaimed soil particle size under seepage conditions after the management period will directly determine the success or failure of reclamation work. The geotechnical experimental method was used in this paper to study the changes in the granulometric composition of soil. The results show that the granulometric composition of the reclaimed soil varied obviously at different depths. The granulometric composition of the soil at a depth of 10 cm was not much different from undisturbed reclaimed soil (URS). At a depth of 30 cm, as the sharp decrease of the content of fine particles resulted in coarser reclaimed soil, the soil became more uniform, with an increase in porosity and water content. At a depth of 50 cm, the fine particle content was generally slightly lower than that of URS. At a depth of 70 cm, the fine particle content of the soil greatly exceeded that of the URS, with the finest soil particles and lowest porosity. The main reason for the above-mentioned changes of granulometric composition in the reclaimed soil was the seepage in soil caused by irrigation during the management period. The research results can provide a reference for management after land reclamation at non-metallic mines in Xinjiang, China.

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