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OF2 A numerical and experimental study on a high efficiency

3 cyclone dust separator for high temperature

4 and pressurized environments

5 Mi-Soo Shin a, Hey-Suk Kim a, Dong-Soon Jang a,*,6 Jin-Do Chung b, Matthias Bohnet c

7 a Chungnam National University, 220 Gung-dong, Taejon 305-764, Republic of Korea8 b Hoseo University, Baebang-Myun, Asan city Chung-Nam 336-795, Republic of Korea9 c Institute of Chemical Engineering Technical university of Braunschweig, Langer Kamp 7, 38106 Braunschweig, Germany

Received 23 January 2004; accepted 5 November 2004

12 Abstract

13 A numerical and experimental study has been made for the development of high efficiency cyclone dust14 separator applicable to the extreme environments of high pressure of 6 bar and temperature up to 400 C.15 The main objective of this study is to develop a handy and reliable computer program and thereby to figure16 out the physical mechanism of dust collection for high temperature and pressure condition.17 The program is developed using Patankars SIMPLE method for the application of 2-D axi-symmetric18 flow field. The two-equation turbulence ke model is employed for the resolution of Reynolds stresses. Fur-19 ther the particle trajectory calculation is made by the incorporation of drag, centrifugal and coriolis force in20 a Lagrangian frame.21 The calculated results predict well the general trend and its magnitude of the experimentally measured22 pressure drop with the condition of increased pressure and temperature as a function of flow rate. Further,

23 experiment shows that the increase of pressure and temperature generally affect significantly the collection24 efficiency of fine particle less than 10 lm but the effect of pressure and temperature appears contrary each

1359-4311/$ - see front matter 2004 Elsevier Ltd. All rights reserved.

doi:10.1016/j.applthermaleng.2004.11.002

* Corresponding author. Tel.: +82 42 821 6677; fax : +82 42 823 8362.

E-mail address: [email protected] (D.-S. Jang).

www.elsevier.com/locate/apthermeng

Applied Thermal Engineering xxx (2004) xxxxxx

ATE 1376 No. of Pages 15, DTD = 5.0.1

3 December 2004 Disk Used ARTICLE IN PRESS
mailto:[email protected]:[email protected]:[email protected]

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25 other. That is, the increase of pressure increases the collection efficiency, while the increase of the temper-26 ature results in the decrease of the efficiency over a certain range of flow rate. This is explained well by the27 variation of the gaseous density and viscosity effect on the drag force and also confirmed successfully by the

28 result of numerical calculation. Therefore the decrease of fractional collection efficiency caused by the high29 operating temperature can be remedied by the increase of operating pressure.30 In order to investigate in more detail the effect of extreme condition on the physics of collection effi-31 ciency, a series of parametric numerical investigations are performed in terms of major cyclone design or32 operational parameters such as tangential velocity and vortex finder length, etc. As expected, tangential33 velocity plays the most important effect on the particle collection even for the elevated temperature and34 pressure condition. But there is no remarkable difference noted between reference and extreme condition.35 And the length of vortex finder has relatively insignificant effect on collection characteristics but the diam-36 eter of vortex finder plays an important role for the enhancement of collection efficiency.37 The incorporation of a proper turbulence model of the nonlinear term appeared by relative velocity38 between gas and particle phase for drag calculation of particle trajectory is considered as one of the impor-

39 tant tasks for the more accurate resolution of physical feature for elevated temperature and pressure con-40 dition in near future.41 2004 Elsevier Ltd. All rights reserved.

42 Keywords: Cyclone separator; Pressure drop; Collection efficiency; High temperature and pressure

43

44 1. Introduction

45 The development of new energy saving technologies in power generation causes a strong impe-46 tus to develop new devices for hot flue gas cleaning at pressurized condition. A cyclone is consid-

47 ered as one of advantageous tools for high temperature gas cleaning due to their simplicity and48 low maintenance requirements. By using suitable materials and methods of construction cyclones49 may be adapted for use in extreme operating conditions such as high temperature, high pressure,

50 and further corrosive gases environments. Therefore, the objective of this study is to investigate51 the behavior of dust particle at an elevated temperature and pressure condition.

52 The schematic diagram of cyclone is shown as in Fig. 1. The dirty gas enters the cyclone tan-53 gentially, describes a descending outer vortex, inverts the direction of motion due to the action of54 increase of static pressure and ascends by an inner vortex exiting at the cyclone top through the

55 vortex finder.56 The larger particles are swept into the cyclone wall by a centrifugal force, which is locally op-

57 posed by aerodynamic drag of radial direction, and are carried towards the bottom of the cyclone58 by the descending outer vortex. The finer particles exit at the top with the carrier gas, together59 with coarser particles that may have been re-entrained and swept by the ascending inner vortex.60 Since cyclones have been used extensively in various industries, a considerable number of exper-

61 imental and theoretical investigations have been performed on cyclone separators to the present.62 Among these, Stairmand [1] presented one of the most popular design guides which suggested that63 the cylinder height and exit tube length be, respectively, 1.5 and 0.5 times of the cyclone body

64 diameter for the design of a high efficiency cyclone. Bryant et al. [2] observed if the vortex touched65 the cone wall, particle re-entrainment occurred and Leith [3] and Bhatia and Cheremisinoff[4] dis-

66 cussed the effects of the cone opening size. Rongbiao et al. [5] were suggested that flow rate

2 M.-S. Shin et al. / Applied Thermal Engineering xxx (2004) xxxxxx



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Nomenclature

u axial velocity (m s1

)v radial velocity (m s1)w tangential velocity (m s1)CD drag coefficient (dimensionless)Re Reynolds numberdp particle diameter (m)

Greek letters

/ general specific dependent variablesq density (kg m3)C/ diffusion coefficient of /S/ source term of /

l dynamic viscosity (kg m1 s1)k turbulent kinetic energy (J kg1)e turbulent kinetic dissipation rate (J kg1 s1)

subscripts

g gas

p particle

h

H

B

De

a

b

Dust tube

Dust

Cleaned gas

Dirty gas

Dirty gas

Dc

S

H : Cyclone heighth : Cylinder height

S : Exit tube lengthDc : Cyclone body diameterDe : Gas exit diametera : Inlet height

b : Inlet widthB : Dust outlet diameter

Fig. 1. Schematic diagram of cyclone illustrating geometrical dimensions.

M.-S. Shin et al. / Applied Thermal Engineering xxx (2004) xxxxxx 3



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67 strongly influenced the efficiency and the reduction in cone size results in higher collection effi-

68 ciency without significantly increasing the pressure drop. Bohnet et al. [68] investigated the effects69 of the pressure drop and grade efficiency at high temperature and high pressure.

70 Although our knowledge of what goes on inside a cyclone has increased over the years, the ex-71 act mechanisms of removing particles and effects of each cyclone dimension as shown in Fig. 1 are

72 still not fully understood due to the complexity of the turbulence itself and the interaction between73 particle and carrier gas. In addition, a radical change of operating conditions by high temperature74 and pressure add even more difficulties to the complicated problem. Therefore, most existing cy-

75 clone theories are based on simplified models or are heavily dependent upon empiricism. The the-76 oretical models need experimentally defined factors to fit theory on experimental data [6].77 Recently, research efforts by computational fluid dynamics are frequently carried out for the res-

78 olution of flow field and dust particle behavior with different degree of numerical and modeling accu-79 racy in order to assist in the time consuming experimental works. In conjunction with the complex

80 flow structure, numerical simulation is momentarily not able to completely substitute experiments81 but can reduce, to a certain degree, experimental costs for design and optimization. Therefore, the82 purpose of this study is to help better understand the particle removing characteristics of cyclone sep-

83 arator especially by exploring the effects of extreme operating conditions caused by high temperature84 and pressure. To this end a relatively well-established numerical method for the simple 2-D axi-sym-

85 metric approximation of cyclone geometry is adopted in this study. The computer program devel-86 oped is validated by the comparison of the experimental data performed in the laboratory of Prof.87 Bohnet in the dept of Chemical Engineering of University of Braunschweig.

88 2. Experimental set-up

89 To receive reliable data for extreme operating conditions, the set-up shown in Fig. 2 has been90 installed. It allowed measurements of pressure drop and grade efficient in a temperature range91 20600 C at a maximum pressure of 6 bar. A three stage compressor delivers the flow rate, which

92 is adjusted by two control valves in the bypass. The pressure is adjusted by one control valve at93 the end of the set-up. The air is heated electrically with two heaters. A rotating brush dosing de-94 vice installed within a pressure vessel is used to feed solids continuously to the gas. A valve in the

95 main stream controls the flow rate through the dosing devices. The collection efficiency curve is96 determined by measuring the particle size distribution and the particle concentration within the97 inlet and outlet gas stream of the cyclone. These data are measured with two light scattering aer-

98 osol counters in-line and simultaneously. The cyclones are fixed in a pressure vessel. This simpli-

99 fies the variation of the cyclone geometry, because the cyclone itself has to be designed100 temperature resistant only [911].

101 3. Numerical modeling

102 3.1. Governing equation

103 The basic gas-phase conservation equations for mass, momentum, energy, turbulence quantities

104 and species concentration can be expressed, in Eulerian cylindrical framework, as




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oq/

ot r q~u/ r Cr/ S/ 1

108 where, / denotes general dependent variables expressed as a physical quantity per unit mass. Fur-109 ther, u, v, w, T, q, C/ and S/ standard for x, y, tangential velocity components, density, tempera-

110 ture, diffusion coefficient, and source term corresponding to /, respectively. Turbulence is modeled111 using the high Reynolds number version of the RNG and standard ke model for Reynolds stress.

112 Table 1 summarizes the diffusion coefficient, C/, and source term, S/, used in this study [12].113 The equations of particle motion can be expressed as

dup

dt aug up 2

dvp

dt avg vp

w2p

rp3

dwp

dt awg wp

vpwp

rp4

123 where,

a 18lgCD

qpd2p

Re

24, CD 0:22

24

Re1 0:15Re

0:6 5

127 In this study the turbulence modeling appeared in drag force caused by the nonlinear term of128 relative velocity between gas and particle phase is not made at this stage in order to eliminate the129 effect of the turbulence modeling of the particle phase on the particle trajectory calculation for the

130 extreme environments. Fig. 3 shows the schematic diagram of the possible 13 trajectories em-131 ployed in the trajectory calculation [13].

Fig. 2. Experimental set-up.




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132 3.2. Numerical algorithm and solution procedure

133 The solution of the Eulerian gas phase equations are done by a control-volume based finite-dif-134 ference procedure. A detailed description of this method is given by Patankar [12]. The method135 requires the division of the computational domain into a number of control volumes, each asso-

136 ciated with a grid point. The governing differential equations in each control volume profile are137 approximated in each coordinate direction. In this study, power-law scheme is employed for

138 the discretization of the convection term appeared in the governing equation (1). A system of dis-139 cretized linear equations as Eq. (6) is solved iteratively due to the nonlinear feature of the equation140 implicitly imbedded in the coefficient the discretized equation [12].

aP/P aE/E aW/W aN/N aS/S b 6

Table 1

/ and C/ expression for 2-D cylindrical coordinate

Variables / C/ S/

Axial momentum u leff o

oxleff

ou

ox

1

r

o

orleffr

ov

ox

op

ox

Radial momentum v leffo

oxleff

ou

or

1

r

o

orleffr

ov

or

2leff

v

r2

qw2

xop

or

Tangential momentum w leff leffr2

qv

r

1

r

oleffor

w

Kinetic energy kleffrk

Gk1qe

Kinetic energy dissipation rate eleff

rs

e

jC1Ck1 C2qe

Temperature Tk

Cp

Gj1 2leffou

ox

2

ov

or

2

v

r

2" # leff

ow

ox

2 r

o

or

w

r

2

ou

orov

ox

2" #

C1 = 1.44, C2 = 1.92, Cl = 0.92, rj = 0.9, re = 1.22

Fig. 3. Particle trajectories in a control volume.




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144 where, aE, aW, aN, aS, and aP are coefficients of east, west, north, south and main grid nodes,

145 respectively.146 Fig. 4 represents the boundary condition of cyclone employed in this study.

147 4. Results and discussion

148 As mentioned above, numerical calculation for the cyclone is performed using the computer149 program developed in this laboratory and compared with experimental data performed at the

150 Institute of Chemical Engineering of University of Braunschweig. In order to investigate the ef-151 fects of pressure drop and particle separation efficiency, the trajectories of particles are calculated152 with various geometrical variables (vortex finder length, vortex finder diameter) and operating153 condition (tangential velocity, flow rate). The detailed dimensions and operating conditions are

154 summarized in Table 2.

Inlet

condition

Right wall

B.C

Bottom wall

B.C

Outflow

B.C

Symmetry

B.C

Top

wall

R1

R2

RF

Fig. 4. Boundary conditions of cyclone used in this study.

Table 2

The specification of cyclone geometry and operating condition employed in this study

Geometry (mm) a Dc De H h S B

Standard 13 100 32 248 55 71 31

Flow rate (m3/h) 10160 (reference flow rate condition: 60)

De/Dc 0.2, 0.4, 0.6

S/Dc 0.2, 0.5, 0.72, 1.0

Tangential velocity (vane angle) 1.01 m/s (30), 1.75 m/s (45), 3.03 m/s (60)

dp[lm] 110

* Refer Fig. 1.




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OF155 First of all, Fig. 5 shows the comparison of calculated and measured pressure drop curves as156 function of flow rate for various temperature and pressure conditions of temperature up to157 400 C and pressure up to 6 bar. The calculation of pressure drop is made by the difference be-

158 tween exit and inlet area-weighted static pressure. As shown in the Fig. 5, the comparison shows159 fairly good agreement over the entire temperature, and pressure range except the case of high flow160 rate with 6 bar, over which there are no experimental data available for direct comparison. But

161 there are some visible difference observed for the case of reference condition, that is, atmospheric162 operating pressure, 1.1 bar and room temperature and the difference becomes more visible as the

163 increase of flow rate. The explanation of this difference is not clear at this stage but is considered

164 possibly due to the combined effect of the numerical and experimental error by the increased flow165 rate. As might be expected, for a given volumetric flow rate, the pressure drop generally increases166 with the increase of gaseous density, that is, high pressure and low temperature condition. This is167 attributed to the effect of increased dynamic pressure and thereby large pressure drop by the in-

168 crease of density for the same flow rate.

0

0.2

0.4

0.6

0.8

1

0.1 1 10

particle size(m)

efficiency,

18 ,1.1bar,60 /h

400 ,1.1bar,60 /h

m3

m3

Fig. 6. The effect of temperature on the measured fraction collection efficiencies for 18 and 400 C temperature.

0

20

40

60

80

100

120

140

160

0 20 40 60 80 100 120 140 160 180

Flow rate(m3/h)

P(mbar)

Calculated

15 , 6 bar

200 , 6bar

400 , 6bar

15 , 1.1bar

Fig. 5. Measured and calculated pressure drops as a function of flow rate for the condition of elevated temperature and

pressure.




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169 Fig. 6 shows the effect of temperature on the measured fractional collection efficiency curves for

170 two temperature conditions of 18 and 400 C at atmospheric pressure. As shown in Fig. 6, the171 fractional collection efficiency of high temperature show lower than that of low temperature over

172 most particle size range except the very fine particle, below 0.5 lm and particle size greater than173 4 lm. The decrease of collection efficiency for the case of high temperature is considered due to

174 the increased viscosity effect as shown in the following argument. If we assume that the radial175 velocity component becomes terminal speed by the equilibrium of centrifugal force with the aero-176 dynamic drag force from particle trajectory equations of Eqs. (2)(5), then the terminal velocity

177 given approximately by the radial velocity component can be expressed approximately as in terms178 of gaseous density and viscosity.

vp $ lg 106qg 7

181 Based on the equation given above, we can conclude that the change of gaseous viscosity plays the

182 more important role than gaseous density to reduce the particle terminal velocity to the wall of183 cyclone.184 Further the relatively small effect of gaseous temperature on the fractional collection efficiency

185 for the range of fine (below 0.5 lm) and large (greater than 1.0 lm) particle size is considered as186 the significantly increased and reduced collection efficiency due to the change of particle inertia.

187 Therefore, this analysis leads to the tentative conclusion that the effect of the increase of operating188 temperature in cyclone plays an important role over a certain range particle size, that is, moderate

189 region of particle inertia.190 Fig. 7 shows the sole effect of increased pressure on the measured fractional collection effi-191 ciency. As shown in Fig. 7, the improvement of the collection efficiency with the increase of pres-

192 sure from 1.1 to 6 bar at a temperature of 18 C is clearly observed. As expected, this is caused by

193 the increased gas phase inertia for a given flow rate, which results in a higher tangential velocity194 leading to higher centrifugal force on a particle.

195 Fig. 8 is a comparison result of the combined effect of increased pressure and temperature on196 the measured fractional collection efficiency between the high temperature and high pressure and197 the ambient reference condition. The overall collection efficiencies of two cases are similar each

0

0.2

0.4

0.6

0.8

1

0.1 1 10

particle size(m)

efficiency,

18 ,1.1bar,60 /h

18 ,6.0bar,60 /h

Fig. 7. The effect of increased pressure on the measured collection efficiency for the pressure of 1.1 and 6 bar.




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0.2

0.4

0.6

0.8

1

0.1 1 10

particle size(m)

efficiency,

18 ,1.1bar,60 /h

400 ,6.0bar,60 /h

Fig. 8. The combined effect of increased pressure and temperature on the measured collection efficiency as a function of

particle size for the condition of 1.1 bar, 18 C and 6 bar, 400 C.

0 0.05 0.1 0.15 0.2X

0

Y

(b) T= 15o

C, P=1.1 bar, 60m3/hr

0 0.05 0.1 0.15 0.2X

0

Y

(b) T= 400o

C, P=1.1 bar, 60m3/hr

0 0.05 0.1 0.15 0.2X

0

Y

(c) T= 15o

C, P=6.0 bar, 60m3/hr

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

0.01

0.02

0.03

0.04

0.05

0.01

0.02

0.03

0.04

0.05

0.01

0.02

0.03

0.04

0.05

Y

(d) T= 400o

C, P=6.0 bar, 60m3/hr

x

r

Inlet

Outlet

Fig. 9. Particle trajectory of various particles (110 lm) with high temperature and pressure (collection efficiency: (a)

90%, (b) 85%, (c) 93%, (d) 87%).




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198 other and for the sub-micron range of particle size the elevated pressure and temperature condi-

199 tion shows a little bit better efficiency and vice versa for the particle size more than 1 lm. Based on200 the result of this Fig. 8, it is clear that the decrease of collection efficiency by the increase of tem-

201 perature can be alleviated by the proper increase of operating pressure of cyclone.202 A number of calculated particle trajectories have been performed with variation of the pressure

203 and temperature for the flow rate of 20, 40, and 60 m3/h, in which representative particle trajec-204 tories are classified with particle size and initial starting location at inlet port. For the case of205 60 m3/h, the particle trajectories are presented in Fig. 9 together with the overall collection effi-

206 ciency based on the result of the representative particle trajectories. As shown in the figure, the207 collection efficiency generally increases with the increase of pressure and decrease of temperature.208 The highest collection efficiency is 93% for the 6 bar and room temperature and the lowest is 85%

209 for the 1.1 bar and 400 C. For the case of the flow rate 40 m3/h, the overall collection efficiency210 shows a little lower or so.

211 In general, the calculated result is fairly consistent with the qualitative trend of the experimental212 observation but the direct comparison with calculation and experiment is not made at this stage

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(a) De/D

C= 0.2

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(b) De/D

C= 0.36

(Standard)

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(c) De/D

C= 0.6

x

r

Fig. 10. Trajectory of particles (110 lm) with the increase of diameter of vortex finder (collection efficiency: (a) 94%,

(b) 87%, (c) 84%).




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213 since the finite grouping of representative classification with particle size and initial location is not

214 sufficient to give fairly accurate quantitative evaluation.215 In order to figure out further the effect of increased temperature and pressure on the cyclone

216 efficiency a series of parametric investigation have been performed in terms of important cyclone217 operating and design variables. Since the pressure and temperature cause opposite effect on cy-

218 clone collection efficiency, the combined effect of pressure and temperature does not show any

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(a) S/DC

= 0.2

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(b) S/DC

= 0.5

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(d) S/DC

= 1.0

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(c) S/DC

= 0.71(standard)

x

r

Fig. 11. Particle trajectory of various particles (110 lm) with increase of vortex finder length (collection efficiency: (a)

78%, (b) 87%, (c) 87%, (d) 86%).




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219 consistent and noticeable difference compared to the result of reference condition. Figs. 1012 rep-

220 resent the particle trajectories calculated with 6.0 bar and 400 C for the flow rate of 60 m3/h.221 In Fig. 10 calculation results show the effect of diameter of vortex finder on particle trajectory.

222 As shown in the figure, the increase of the diameter of vortex finder reduces the collection effi-223 ciency since the effect of increased static pressure inside the vortex tube overwhelms the increased

224 centrifugal force outside the vortex tube caused by the decreased area by the increase of tube225 diameter. A similar result can be also found by the experimental work by Bryant et al. [2].226 The calculation results of particle trajectory for various length of vortex finder, S is shown in

227 Fig. 11. The vortex finder length has insignificant effect on collection efficiency s over a certain228 range but excessively short (less than S/Dc = 0.2) length reduces the collection efficiency due to229 early exposure of low pressure region near vortex finder.

230 Collection efficiency significantly increases with the increase of tangential velocity as shown in231 Fig. 12. Higher tangential velocity causes higher centrifugal force and results in a reduction of the

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(a) w = 1.01 (30o)

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(b) w = 1.75 (45o

)

0 0.05 0.1 0.15 0.2X

0

0.01

0.02

0.03

0.04

0.05

Y

(c) w = 3.03 (60o)

x

r

Fig. 12. Trajectory of particles (110 lm) with increase of tangential velocity (collection efficiency: (a) 67%, (b) 79%, (c)

87%).




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232 cut size of collected particles. Furthermore, the calculation data show that cyclones have an essen-

233 tial ability to remove fine particles at high tangential velocity. Contrary to conventional idea that234 cyclones are not suitable for removing particles smaller than 1 lm, this study shows that it has a

235 sufficient ability to collect particles whose diameters are much smaller than 1 lm at high tangen-236 tial velocity.

237 5. Conclusion

238 Based on a series of numerical investigation and experiment, a number of useful conclusions239 can be drawn for the case of extreme operating condition caused by high temperature and pres-

240 sure condition.241 The calculated results predict well the general trend and its magnitude of the experimentally

242 measured pressure drop with the condition of increased pressure and temperature as a function243 of flow rate. Further, experiment shows that the increase of pressure and temperature generally244 affect significantly the collection efficiency of fine particle less than 10 lm but the effect of pressure

245 and temperature appears contrary each other. That is, the increase of pressure increases the col-246 lection efficiency, while the increase of the temperature results in the decrease of the efficiency over

247 a certain range of flow rate.248 In order to investigate in more detail the effect of extreme condition on the physics of collection249 efficiency, a series of parametric numerical investigations are performed in terms of major cyclone

250 design or operational parameters such as tangential velocity, vortex finder length and diameter.251 Tangential velocity plays the most important effect on the particle collection even for the elevated252 temperature and pressure condition. But in general there is no remarkable difference noted be-

253 tween reference and extreme condition. Therefore, the decrease of fractional collection efficiency254 by the operating condition of high temperature can be remedied by the increase of operating255 pressure.

256 The incorporation of a proper turbulence model of the nonlinear term appeared by relative257 velocity between gas and particle phase for drag calculation of particle trajectory is considered258 as one of the important tasks for the more accurate resolution of physical feature for elevated tem-

259 perature and pressure condition in near future.

260 References

261 [1] C.J. Stairmand, The design and performance of cyclone separators, Trans. Inst. Chem. Eng. 29 (1951) 356383.262 [2] H.S. Bryant, R.W. Silverman, F.A. Zenz, How dust in gas affects cyclone pressure drop, Hydrocarbon Process. 62263 (1983) 8790.

264 [3] J. Dirgo, D. Leith, Performance of theoretically optimized cyclones, Filterat. Separat. 22 (1985) 199225.265 [4] M.U. Bhatia, P.N. Cheremisinoff, Cyclones, in: P.N. Cheremisinoff (Ed.), Air Pollution Control and Design for266 Industry, Marcel Dekker, New York, 1993.

267 [5] S.H. Rongbiao, K.W. Xiang, K.W. Park, K.W. Lee, Effects of cone dimension on cyclone performance, Aerosol268 Sci. 32 (2001) 549561.

269 [6] C.H. Kim, J.W. Lee, A new collection efficiency model for small cyclones considering the boundary layer effect, J.270 Aerosol Sci. 32 (2000).




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271 [7] M. Michael, W. Martin, Pressure loss and separation characteristics calculation of a uniflow cyclone with a CFD272 method, Chem. Eng. Technol. 23 (2000) 753758.

273 [8] M.A. Silva, S.A. Nebra, Numerical simulation of drying in a cyclone, Drying Technol. 15 (6-8) (1997) 17311741.

274 [9] M. Bohnet, Cyclone separation for fine particles and difficult operating conditions, KONA Powder Particles (12)275 (1994) 6976.276 [10] M. Morweiser, M. Bohnet, Design calculation of aerocyclones for extreme operating conditions, in: 12th277 International Congress of Chemical and Process Engineering, 1996, pp. 5566.

278 [11] M. Morweiser, M. Bohnet, Influence of operating conditions on grade efficiency and pressure drop of aerocyclone,279 in: 3rd International Conference on Multiphase Flow, ICMF98, 1998, pp. 18.

280 [12] S.V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere, Washington, DC, 1980.281 [13] D.S. Jang, Single and Two-Phase Reacting Flow Predictions Modeling of Nonequilibrium Effects, Turbulent282 Particle Dispersion and Nitrogen Oxide Formation in Pulverized Coal Combustor, Doctor Thesis, Louisiana State283 University, USA, 1987.

284




Date post:	07-Apr-2018
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Cyclone 2005

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