Abstract—The performance of collection efficiency of cylindrical inlet-type cyclone separator for relatively low solid loading rate conditions is reported. Cyclone separators usually operate under high solid loading conditions, but the demand of air pollution control at outdoor densely polluting activities as construction sites and application of power generators, it is advantageous to use cyclone separators to control outdoor air pollution by cyclone separators. Grade efficiencies and overall collection efficiencies have been investigated from 0.008g/m 3 to 0.2g/m 3 solid loading rates at 5m/s and 10m/s inlet velocity conditions. Experimental data were compared with two theoretical predictions based on empirical and mechanistic relationships, developed by Smolik and Muschelknautz. To achieve a better understanding of particle separation efficiency, particle cut size diameter for selected loading rate were considered with theoretical approached by Muschelknautz model. Both experimental and theoretical results showed that with the increase of solid loading rate and inlet velocity, the particle collection efficiency of cyclone separator increases. Index Terms—Cut size diameter, cyclone separator, grade efficiency, solid loading rate, swirling flow, overall collection efficiency. NOTATION B cone tip/hopper diameter C 1 given inlet solid concentration C 2 any inlet solid concentration D body diameter D 50 particle cut size diameter D e vortex finder diameter D i inlet diameter D o outlet diameter H total height H co cyclone conical body height H cy cyclone cylindrical body height H h cyclone hopper height m h solid mass collected in hopper m in total inlet mass x fact modification factor of cut size diameter ( by Muschelknautz) η (C 1 ) given efficiency η (C 2 ) calculated efficiency η overall overall collection efficiency I. INTRODUCTION Cyclone separators are extensively used for a particle Manuscript received April 4, 2014; revised June 4, 2014. G. B. Sakura and Andrew Y. T. Leung are with the Department of Civil and Architectural Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China (e-mail: sganegama2-c@ my.cityu.edu.hk, [email protected]). controlling industries as, air pollution control, aerosol sampling and particulate matter control, due to their simplicity of design, inexpensive manufacturing cost, ease in maintenance and adaptability to a wide range of operating conditions [1]. Despite of simplicity and other operational advantages, well designed cyclone separators can be efficiently remove particles larger than 2 micrometer in size [2]. Cyclone separators can be classified according to their body shape, inlet configuration, and inlet/outlet flow direction [3]. Most popular cyclone separator type is reversed flow type which consists of a slot type inlet and a conical-body (cylinder-on-cone). Relevant to the literature, many studies (e.g., [4] and [5]) have been performed theoretical, experimental and lately computational fluid dynamic (CFD) simulations to understand the performance of slot type inlet cyclone separators by considering geometry and operational conditions. These researches were also involved to develop design parameters and relationships in order to improve and estimate collection efficiency. To increase the performance of cyclone separator, knowledge based on effect of particle solid loading rate is one of main parameter for any type of cyclone design. Earliest study [6], have been stated that, there could be a small increment of collection efficiency with the increase of solid loading under the assumption of coarser particles carry finer particles to cyclone wall region. But a survey of experimental results from literature considering a loading range of 2.3 to 228.8g/m 3 , has showed a increase of collection efficiency with the increase of solid loading rate [7] (as reported by [8]). For coarse range particle application is observed the same behavior for particle loading rate up to 100g/m 3 [9]. Similar observation is also reported by [10] for particle loading rates up to 235.2 g/m 3 , conducted under different inlet velocity and temperature conditions. This study further observed an increment of the collection efficiency with increase of temperature. Rising solid loading rate from 4.98g/m 3 to 130.8g/m 3 at three different inlet velocity conditions, noticed a dramatic increment of overall collection efficiency at low velocity conditions [11], [12]. Considering extremely low particle loading rates, from 5mg to 20000mg, overall and grade efficiency curves were studied by [8], for small scale cyclone separators and observed a similar increment behavior for low to high inlet velocity conditions. In addition, this study indicated that at low solid loading conditions, particle agglomeration is significant in particle separation. Although many of literature show a increase of overall collection efficiency with increase of solid loading rate, a reduction of collection efficiency by solid loading rate increment from 1.69g/m 3 to 6.72g/m 3 was observed by [13]. Similar trend was observed for the study Experimental Study of Particle Collection Efficiency of Cylindrical Inlet Type Cyclone Separator G. B. Sakura and Andrew Y. T. Leung International Journal of Environmental Science and Development, Vol. 6, No. 3, March 2015 160 DOI: 10.7763/IJESD.2015.V6.581
5
Embed
experimental study of particle collection efficiency of cylindrical inlet type cyclone seperator
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Abstract—The performance of collection efficiency of
cylindrical inlet-type cyclone separator for relatively low solid
loading rate conditions is reported. Cyclone separators usually
operate under high solid loading conditions, but the demand of
air pollution control at outdoor densely polluting activities as
construction sites and application of power generators, it is
advantageous to use cyclone separators to control outdoor air
pollution by cyclone separators. Grade efficiencies and overall
collection efficiencies have been investigated from 0.008g/m3 to
0.2g/m3 solid loading rates at 5m/s and 10m/s inlet velocity
conditions. Experimental data were compared with two
theoretical predictions based on empirical and mechanistic
relationships, developed by Smolik and Muschelknautz. To
achieve a better understanding of particle separation efficiency,
particle cut size diameter for selected loading rate were
considered with theoretical approached by Muschelknautz
model. Both experimental and theoretical results showed that
with the increase of solid loading rate and inlet velocity, the
particle collection efficiency of cyclone separator increases.
Index Terms—Cut size diameter, cyclone separator, grade