[an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive]
[an error occurred while processing this directive]

Gold Science and Technology >

2020 , Vol. 28 >Issue 2: 188 - 194

DOI: https://doi.org/10.11872/j.issn.1005-2518.2020.02.198

Measurement of Bubble Size Distribution in Surface Aeration Reactor

  • Yixiao HAO , 1 ,
  • Xuefeng ZHENG 1 ,
  • Yiting XIAO 2, 3 ,
  • Haoliang WANG 2, 3 ,
  • Xiangyang LI , 2
Expand
  • 1. Wuhuan Engineering Co. ，Ltd，Wuhan 430223，Hubei，China
  • 2. CAS Key Laboratory of Green Process and Engineering，Institute of Process Engineering，Chinese Academy of Sciences，Beijing 100190，China
  • 3. School of Chemical Engieering，University of Chinese Academy of Sciences，Beijing 100049，China

Received date: 2019-12-31

  Revised date: 2020-02-25

  Online published: 2020-05-07

Fold

Highlights

It is necessary to do well the waste water produced by mining in green mines.In the surface aeration reactor，the unreacted gas is entrained from the space above the liquid level and dispersed again through the violent turbulence formed by the surface aeration paddle on the liquid surface.Therefore，a series of processes such as separation，purification，compression and recycling of unreacted gas can be omitted by using surface aeration，which is of great significance to reduce equipment investment and operation cost.Waste water treatment using surface aeration is helpful to save energy consumption.At present，there is no research reported on the local property distribution of bubbles in the surface aeration reactor，which is the necessary basis for the accurate design of the reactor.Sharp pictures of bubble motion can be obtained by using the newly developed multi-phase measuring instrument based on the telecentric photography.Then，a series of image processes including enoising，filtering （Gaussian filtering and Median filtering），binarization and in-focus bubbles detection are conducted.Thus，bubble size distribution is obtained and consequently，the specific surface area and bubble holdup distribution are further obtained.Using this method，bubble hydrodynamics in the surface aeration reactor is systematically measured.The axial position and stirring speed are mainly investigated.The results show that the bubble size in the surface aeration reactor is smaller than that in the gas-liquid agitated reactor supplied by the gas distributor.Along the axial direction downwards，the bubble size gradually decreases and the number of bubbles decreases on the whole.This can be explained qualitatively by the different gas dispersion model in surface aeration reactor and gas-liquid stirred tank.The effect of impeller speed is studied on B position.With the increase of the impeller speed from 350 r/min to 450 r/min，the number of suction bubbles increases and the average bubble size increases.In order to strengthen the gas-liquid dispersion process in the surface aeration reactor，two advices are provided：In a shallow bed，zones with fewer bubbles will be greatly reduced.So，such design is more advantageous，and the increase of impeller speed can strengthen the turbulence near the liquid surface and the overall fluid circulation.Thus，it is also appropriate to increase impeller speed within the allowable range of power. This study will provide a new choice for the efficient treatment of green mine wastewater.

Cite this article

Yixiao HAO , Xuefeng ZHENG , Yiting XIAO , Haoliang WANG , Xiangyang LI . Measurement of Bubble Size Distribution in Surface Aeration Reactor[J]. Gold Science and Technology, 2020 , 28(2) : 188 -194 . DOI: 10.11872/j.issn.1005-2518.2020.02.198

[an error occurred while processing this directive]

References

Publishing order | Descend order by publishing year | Descend order by cited within
1
李向阳，禹耕之，毛在砂.双层桨表面曝气反应器构型优化[J].过程工程学报，2005，5（6）：601-604.

Li Xiangyang， Yu Gengzhi， Mao Zaisha.Optimization of dual-impeller configuration of gas-liquid surface aerator[J].The Chinese Journal of Process Engineering，2005，5（6）：601-604.

2
Patwardhan A， Joshi J.Design of stirred vessels with gas entrained from free liquid surface[J].The Canadian Journal of Chemical Engineering，1998，76（3）：339-364.

3
毛在砂，禹耕之，王蓉.组合式表面曝气搅拌桨：CN1310040A[P].2001-08-29.

Mao Zaisha， Yu Gengzhi， Wang Rong.Combined surface aeration agitator：CN1310040A [P]. 2001-08-29.

4
Yu G， Mao Z， Wang R.A novel surface aeration configuration for improving gas-liquid mass transfer [J].Chinese Journal of Chemical Engineering，2002，10（1）：39-44.

5
Matsumura M， Sakuma H， Yamagata T，et al.Gas entrainment in a new gas entraining fermentor [J].Journal of Fermentation Technology，1982，60（1）：457-467.

6
Matsumura M， Sakuma H， Yamagata T，et al.Performance of oxygen transfer in a new gas entraining fermenter[J].Journal of Fermentation Technology，1982，60（1）： 551-563.

7
Wu H.An issue on application of a disk turbine for gas-liquid mass transfer[J].Chemical Engineering Science，1995，50（17）：2801-2811.

8
Veljkovic V， Skala D.Effect of number of turbine impellers on surface aeration in laboratory fermenter[J].Biotechnology and Bioengineering，1989，34（2）：207-213.

9
王爱华，禹耕之，毛在砂.带自旋自浮挡板的表面曝气装置气液传质特性研究[J].石油炼制与化工，2004，35（1）：51-54.

Wang Aihua， Yu Gengzhi， Mao Zaisha.Characteristics of gas-liquid mass transfer of surface aerator with self- rotating floating baffle[J].Petroleum Processing and Petrochemicals，2004，35（1）：51-54.

10
李良超.气液反应器局部分散特性的实验与数值模拟[D].杭州：浙江大学，2008.

Li Liangchao.Experiment and Numerical Simulation of Local Gas Dispersion in Gas-Liquid Reactors[D].Hangzhou：Zhejiang University，2008.

11
Parul T， Vivek V.Experimental characterization of dense gas-liquid flow in a bubble column using voidage probes[J].Chemical Engineering Journal，2017，308：912-928.

12
Dominic P， Valois P， Connor F，et al.Particle agglomeration in gas-liquid-solid fluidized beds with a dispersed immiscible liquid：Study on particle size，shape and material[J].Powder Technology，2014，266：45-60.

13
Besagni G， Inzoli F.Bubble size distributions and shapes in annular gap bubble column[J].Experimental Thermal and Fluid Science，2016，74：27-48.

14
Busciglio A， Grisafi F， Scargiali F，et al.On the measurement of local gas hold-up，interfacial area and bubble size distribution in gas-liquid contactors via light sheet and image analysis：Imaging technique and experimental results[J].Chemical Engineering Science，2013，102：551-566.

15
Maaß S， Wollny S， Voigt A，et al.Experimental comparison of measurement techniques for drop size distributions in liquid/liquid dispersions[J].Experiments in Fluids，2011，50（2）：259-269.

16
Shi B H， Chai S， Ding L，et al.An investigation on gas hydrate formation and slurry viscosity in the presence of wax crystals[J].AIChE Journal，2018，64（9）：3502-3518.

17
Kacker R， Maaß S， Emmerich J，et al.Application of inline imaging for monitoring crystallization process in a continuous oscillatory baffled crystallizer[J].AIChE Jour- nal，2018，64（7）：2450-2461.

18
李向阳，王浩亮，冯鑫，等.多相反应器的非均相特性测量技术进展[J].化工进展，2019，38（1）：45-71.

Li Xiangyang， Wang Haoliang， Feng Xin，et al.Progresses in measurement technologies of heterogeneous characteristics in multiphase reactors[J].Chemical Industry and Engineering Progress，2019，38：45-71.

19
Wang G， Li X， Yang C，et al.New vision probe based on telecentric photography and its demonstrative applications in a multiphase stirred reactor[J].Industrial and Engineering Chemistry Research，2017，56（23）：6608-6617.

Options
Outlines

/

〈 〉

[an error occurred while processing this directive]