摘要
气溶胶污染的防治问题是当前能源环境领域的研究热点和难点,然而迄今为止在工程中缺乏普适性的气溶胶捕集设备。本文针对气体中液体气溶胶微粒(以下简称微液滴)的分离捕集,设计了不同公称直径的五种微旋流器,搭建了配有相位多普勒粒子分析仪(PDPA)、图像法粒度仪的微旋流捕集装置,测试研究了微旋流器的结构参数和操作条件对分离压降和效率的影响。主要结论如下:
(1)发现了气液旋流分离过程中气体泄漏强化分离过程的现象,发明了底流漏气强化分离的工艺,建立了漏气强化旋流分离的实验装置。在漏气工况下,DN100、DN150、DN200微旋流器的压降有所增加,而DN75微旋流器则由于液腿内湍动能耗降低出现了压降减小的情况,在含液浓度为0.5g/m3,微液滴平均粒径为7gm条件下,DN75微旋流器的最高分离效率从95%攀升至98%。
(2)与DN25、DN100、DN150、DN200微旋流器相比,DN75微旋流器的分离效率更高,在压降为32mmH20、含液浓度为0.5g/m3,微液滴平均粒径为7μm条件下,DN75微旋流器的出口气体含液浓度仅为25mg/m3,优于国家标准GB13223-2003。
(3)DN75、DN100、DN150、DN200微旋流器的极限压降Δ乃分别为32mmH20、25mmH2O、20mmH2O、34mmH20,仅为常规旋风分离器的1/5-1/3,而对应的进气速度均为8.4m/s。文中还建立了新压降计算模型。
The aerosol prevention and treatment is the hot issue in the field of energy and environment but with many difficulties. No economical equipments are available for aerosol capturing in engineering practice up to now. It is designed in this article 5 types of mini-cyclones for aerosol capturing with different nominal diameters. A set of equipments with Phase Doppler Particle Analyzer (PDPA) for cold model experiments is established and the influence of the structural and operational parameters on the pressure drop and separation efficiency is studied. The main work in this research is listed as following:
(1) The enhanced separation with air leak is found in gas-liquid cyclonic separation and the enhancement process with air leak is invented and the equipment based on this process is established. The pressure drop of three mini-cyclones (DN100, DN150 and DN200) increase slightly with air leak, while that of the DN75 mini-cyclone decreases due to the decreased energy consumption of turbulence in the dipleg, meanwhile the maximum separation efficiency increase from 95% up to 98% and the correspondent split ratio to the highest efficiency is 10%.
(2) Compared with four mini-cyclones (DN25, DN100, DN150 and DN200), the separation efficiency of the DN75 mini-cyclone reaches to a higher level. The liquid concentration of outlet gas is only 25mg/m3 when the air volume is 40m3/h, the liquid concentration is 0.5g/m3 and the average droplet size is 7μm, superior to National Standard GB13223-2003.
(3) The extreme pressure drop of four mini-cyclones (DN75, DN100, DN150 and DN200) is 32mmH2O,25mmH2O,20mmH2O,34mmH2O respectively, only 1/5~1/3 of that of conventional cyclone, while the inlet air velocity of them is all for 8.4m/s. In this paper, a brand-new model for pressure prediction is also established.
引文
[1](美)诺埃尔.德.内韦尔.大气污染控制工程.北京:化学工业出版社,2005
[2](美)保罗.A.巴伦,克劳斯.维勒克.气溶胶测量原理、技术及应用.北京:化学工业出版社,2007
[3]Mizuno. Electrostatic precipitation. IEEE Trans on Dielectrics and Electrical Insulation, 2000,17(5):615-624
[4]朱法华.袋式除尘技术的发展及其在燃煤电厂烟气处理中的应用.中国电力,2002,35(8):1-6
[5]F.P. Errington, E.O. Powell. A cyclone separator for aerosol sampling in the field. Cambridge Univ Press,1969,67:387-399
[6]吕文杰,汪华林,毛松柏等.烟道气二氧化碳捕集系统尾气旋转流净化方法与装置.申请号:CN201110085039.4;申请日:2011-04-08
[7]肖云鹏,沈其松,李剑平,李志明.低入口浓度下微旋风分离器的试验研究.化工机械,2011,38(6):687-691
[8]Albam J. Lynch, Chester A. Rowland. The history of grinding. Society for Mining, Metallurgy, and Exploration, Inc.(SME), Colorado, USA,2005:149-152
[9]Chun-Jinn Tsai, Sheng-Chieh Chen, Rafal Przekop, Arkadiusz Moskal. Study of an axial flow cyclone to remove nanoparticles in vacuum, Environ. Sci. Technol.,2007,41: 1689-1695
[10]Zhishan Bai, Zhuoqun Qian, Ji Ma, Ping Zhou, Yanhong Zhang, Hualin Wang. Process and apparatus for separating and recovering waste alkali from cyclohexane oxidation solution, U.S. Patent, Application NO.12/358,004
[11]Sie Huey Lee, Desmond Heng, Wai Kiong Ng, Hak-Kim Chan, Reginald B.H. Tan. Nano spray drying:A novel method for preparing protein nanoparticles for protein therapy. International Journal of Pharmaceutics,2011,403(1-2):192-200
[12]范文正,于海滨.直升机进气防护装置的现状和发展趋势.航空科学技术,2000,1:31-32
[13]A.D. Maynard. A simple model of axial flow cyclone performance under laminar flow conditions. Journal of Aerosol Science,2000,31(2):156-167
[14]F.T.M. Nieuwstadt, M. Dirkzwager. A fluid mechanics model for an axial cyclone separator. Industrial Engineering and Chemical Research,1995,34(10):3399-3404
[15]J.K. Briant, O.R. Moss. The influence of electrostatic charge on the performance of 10-mm nylon cyclones. American Industrial Hygiene Association Journal,1984,45(7): 440-445
[16]郝文阁,王尚元,丁妹,吴岩.微型旋风器分离超细粉尘的性能.东北大学学报(自然科学版),2008,29(4):581-584
[17]L.C. Kenny, R. Gussman, M. Meyer. Development of a sharp-cut cyclone for ambient aerosol monitoring applications. Aerosol Science and Technology,2000,32(4): 338-358
[18]金有海,时铭显.PDC型高效旋风管的开发研究.石油炼制与化工,1996,27(2):47-52
[19]江津河,李建,李建隆.环流式旋风分离器用于超细颗粒分级的实验研究.潍坊学院学报,2010,10(2):85-87
[20]G.E. Kouba,O. Shoham, S. Shirazi. Design and performance of gas-liquid cylindrical cyclone separators. BHR Group 7th International Conference on Multiphase Flow,1995: 307-327
[21]魏伟胜,樊建华,鲍晓军,石冈.旋流板式气液分离器的放大规律.过程工程学报,2003,3(5):390-395
[22]罗晓兰,易伟,张海玲,魏耀东.高入口浓度下PV型旋风分离器的分离效率计算.化工学报,2010,61(9):2417-2423
[23]黄盛珠,马春元,吴少华.下排气旋风分离器的改进设计.动力工程,2004,24(5):736-738
[24]Chuen-Jinn Tsai, Horng-Guang Shiau, Kuo-Ching Lin, Tung-Sheng Shih. Effect of deposited particles and particle charge on the penetration of small sampling cyclones. Journal of Aerosol Science,1999,30(3):313-323
[25]C.B. Shepherd, C.E. Lapple. Flow pattern and pressure drop in cyclone dust collectors. Industrial and Engineering Chemistry,1940,32(9):1246-1248
[26]R.M. Alexander. Fundamentals of cyclone design and operation. Proceedings of the Australian Institute of Mineral and Metallurgy(New Series),1949,152-153:203-228
[27]M.W. First. Cyclone dust collector design. ASME Annual General Meeting,1949: 49A127
[28]C.J. Stairmand. Pressure drop in cyclone separators. Industrial and Engineering Chemistry,1949,16(B):409-411
[29]W. Barth. Design and layout of the cyclone separator on the basis of new investigations. BWK,1956,8(4):1-9
[30]A. Avci, I. Karagoz. Theoretical investigation of pressure losses in cyclone separators. International Communication of Heat and Mass Transfer,2001,28(1):107-117
[31]Bingtao Zhao. A theoretical approach to pressure drop across cyclone separators. Chemical Engineering Technology,2004,27:1105-1108
[32]I. Karagoz, A. Avci. Modelling of the pressure drop in tangential inlet cyclone separators. Aerosol Science and Technology,2005,39(9):857-865
[33]J. Chen, M. Shi. A universal model to calculate cyclone pressure drop. Powder Technology,2007,171(3):184-191
[34]A.C. Stern, K.J. Caplan, P.D. Bush. Cyclone Dust Collectors. New York:American Petroleum Institute,1955
[35]D. Leith, D. Mehta. Cyclone performance and design. Atmospheric Environment,1973, 7(5):527-549
[36]D. Leith, J. Dirgo, W.T. Davis. Air Pollution(third ed.), New York:Academic Press, 1986
[37]K.J. Caplan. Source control by centrifugal force and gravity. Air Pollution(third ed.), 1977, Ⅳ:97-148
[38]J. Casal, J.M. Martinez-Benet. A better way to calculate cyclone pressure drop. Chemical Engineering,1983,90(2):99-100
[39]J. Dirgo. Relationship between cyclone dimensions and performance [Doctoral Thesis]. USA:Harvard University,1988
[40]J. Gimbun, T.G. Chuah, A. Fakhru'1-Razi, T.S.Y. Choong. The influence of temperature and inlet velocity on cyclone pressure drop:a CFD study. Chemical Engineering and Processing,2005,45(1):7-12
[41]Bingtao Zhao. Modeling pressure drop coefficient for cyclone separators:A support vector machine approach. Chemical Engineering Science,2009,64(19):4131-4136
[42]J.A. Finch. Modelling a fish-hook in hydrocyclone selectivity curves. Powder Technology,1983,36:127-129
[43]B. Wang, A.B. Yu. Computational investigation of the mechanisms of particle separation and "fish-hook" phenomenon in hydrocyclones. AIChE Journal,2010,56(7): 1703-1715
[44]K.J. Hwang, W.S. Hsueh, Y. Nagase. Mechanism of particle separation in small hydrocyclone. Drying Technology,2008,26(8):1002-1010
[45]T. Neesse, J. Dueck, L. Minkov. Separation of finest particles in hydrocyclones. Minerals Engineering,2004, (5):689-696
[46]H. Schubert. On the origin of anomalous shapes of the separation curve in hydrocyclone separation of fine particles. Particulate Science and Technology,2004, (3):219-234
[47]A.K. Majumder, H. Shah, P. Shukla, J.P. Barnwal. Effect of operating variables on shape of fish-hook curves in cyclones. Minerals Engineering,2007, (2):204-206
[48]F.S. Kilavuz, O.Y. Gulsoy. The effect of cone ratio on the separation efficiency of small diameter hydrocyclones. International Journal of Mineral Processing,2011,98:163-167
[49]R. Parker, R. Jain. Particle collection in cyclones at high temperature and high pressure. Environmental Science & Technology,1981,15(4):451-458
[50]许世森.细微尘粒的预团聚对旋风分离器高温除尘性能影响的实验研究.动力工程,1998,19(4):309-313
[51]Jianyi Chen, Mingxian Shi. Analysis on cyclone collection efficiencies at high temperature. China Particuology,2003,1(1):20-26
[52]李文琦,陈建义.旋风分离器高温性能试验研究.中国石油大学学报:自然科学版,2006,30(3):97-100
[53]H. Mothes, F. Loffler. Motion and deposition of particles in cyclones. Ger Chem Eng, 1985(8):223-233
[54]侯广信,陈建义.颗粒碰撞团聚对旋风分离器分离性能影响研究.石油机械,2008, 36(5):1-4
[55]刘毅.轻质分散相旋流器溢流管优化与柱段流场研究[硕士学位论文].上海:华东理工大学,2010
[56](丹)A.C.霍夫曼,(美)L.E.斯坦因.旋风分离器(原理设计与工程应用).北京:化学工业出版社,2004
[57]H. Buttner. Dimensionless representation of particle separation characteristic of cyclones. Journal of Aerosol Science,1999,30(10):1291-1302
[58]J.P. Maclean, J.D. Brown, H.D. Hoy, J.E. Cantwell. UK Patent, Application No. GB 2011285A
[59]P. Olley, J. Archer, D. Copley, P. Core, A. Mincher. Analysis and design of a centrifugal filter geometry for entrained particle separation. Journal of Aerosol Science, 2010,41(9):848-858
[60]Khairy Elsayed, Chris Lacor. The effect of cyclone inlet dimensions on the flow pattern and performance. Applied Mathematical Modelling,2011,35(4):1952-1968
[61]P.K. Bose, K. Roy, N. Mukhopadhya, R.K. Chakraborty. Improved theoretical modeling of a cyclone separator. International Journal of Automotive Technology,2010, 11(1):1-10
[62]Rainier Hreiz, Caroline Gentric, Noel Midoux. Numerical investigation of swirling flow in cylindrical cyclones. Chemical Engineering Research and Design,2011,89(12): 2521-2539
[63]Ta-Chih Hsiao, Daren Chen, Paul S. Greenberg, Kenneth W. Street. Effect of geometric configuration on the collection efficiency of axial flow cyclones. Journal of Aerosol Science,2011,42(2):78-86
[64]A. Kolbl, M. Kraut, A. Wenka. Design parameter studies on cyclone type mixers. Chemical Engineering Journal,2011,167(2-3):444-454
[65]赵洪英,蔡乐才.超声波雾化器雾滴飞行时间的分析.四川理工学院学报(自然科学版),2010,23(1):88-90
[66]王贞涛,岑旗钢,罗惕乾.双流体喷嘴雾化特性实验.化学工程,2010,38(2):26-30
[67]魏伟胜,杨彦文,鲍晓军,石冈.气液分离器的模拟实验.石油化工,2003,32(9):779-782
[68]金有海,时铭显.含尘气体中颗粒采样与测定方法.石油大学学报(自然科学版),1990,14(4):51-60
[69]张力虎,关平,张龙,贺伟,李洪斌PDPA和激光全息术对喷嘴雾化特性的对比测量,江汉大学学报(自然科学版),2009,37(4):26-28
[70]魏琪,岑旗铜.喷嘴雾化特性的PDPA实验研究进展,排灌机械,2003,21(4):27-30
[71]蔡小舒,苏明旭,沈建琪.颗粒粒度测量技术及应用.北京:化学工业出版社,2010
[72]金向红,金有海,王建军,汪秀敏,张金亮,孙治谦.改进气液旋流器排气管结构的实验及CFD模拟研究.高校化学工程学报,2011,25(2):205-211
[73]Cuizhi Gao, Guogang Sun, Ruiqian Dong, Shuangcheng Fu. Characterizing the dynamic property of the vortex tail in a gas cyclone by wall pressure measurements. Fuel Processing Technology,2010,91(8):921-926
[74]蔡安江.旋风分离器设计计算的研究.化工矿物与加工,2003,32(8):21-23
[75]Mohsen Azadi, Mehdi Azadi. An analytical study of the effect of inlet velocity on the cyclone performance using mathematical models. Powder Technology,2012,217: 121-127
[76]Zhongli Ji, Zhiyi Xiong, Xiaolin Wu, Honghai Chen, Hongxiao Wu. Experimental investigations on a cyclone separator performance at an extremely low particle concentration. Powder Technology,2009,191(3):254-259
[77]Romualdo Salcedo, Julio Paiva. Pharmaceuticals:Efficient cyclone systems for fine particle collection. Filtration & Separation,2010,47(1):36-39
[78]Julio Paiva, Romualdo Salcedo, Paulo Araujo. Impact of particle agglomeration in cyclones. Chemical Engineering Journal,2010,162(3):861-876
[79]王峻晔,葛晓陵,吴东棣.分支流理论研究进展.力学进展,1998,28(3):392-401
[80]金向红,金有海,王建军.气液旋流器内液滴破碎和碰撞的数值模拟.中国石油大学学报(自然科学版),2010,34(5):114-120
[81]Fuat Kaya, Irfan Karagoz. Numerical investigation of performance characteristics of a cyclone prolonged with a dipleg. Chemical Engineering Journal,2009,151(1-3):39-45
[82]李秋萍,邵国兴,程建伟.湿式动力波洗涤器的工业应用.化工装备技术,2006,27(1):17-20
[83]李剑平,汪华林等.一种冷高压分离器的微旋流强化分离装置和方法.申请号:CN201110265426.6;申请日:2011-09-08