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A Novel Ultrasonic Dynamic Drainage Tester
Jinlan J X j n H a and H ining Xiao*Jinlan Ju, Xujun Hua and Huining Xiao*
FPInnovations, Canada
* University of New Brunswick, Canada
PaperCon 2011 Page 306
Water Removal in Papermaking
Former Presses Dryers
1% 20% 45-50% 92%1% 20% 45 50% 92%
Solids Content
100
Fiber Water Content (kg/kg)
100
1010
PaperCon 2011 Page 307
Cost of Water Removal
Relative cost to remove a given quantity of water:
$1 $58 $220Former Presses Dryers
Relative cost to remove a given quantity of water:
$1 $58 $220
PaperCon 2011 Page 308
Conventional Drainage Tester
Canadian Standard F T tFreeness Tester:
Excellent tool for pulp lit t lquality control
PaperCon 2011 Page 309
Dynamic Drainage Jar
A very useful device for d t i i fi tdetermining first pass retention.
PaperCon 2011 Page 310
Modified Dynamic Drainage Jar
Dynamic Drainage Analyzer:
A simple test, but no turbulence duringdrainagedrainage
PaperCon 2011 Page 311
Effect of Mixing on Drainage in Modified DDJ
400400
No mixing
300
ght (
g)
300
No mixing14.1s
Mixing at 400rpm
200
ate
Wei
g
200Mixing at 1000 rpm
Mixing at 400rpm17.0s
100
Filtr
a
100
38.1s
00 10 20 30 40 50
00 10 20 30 40 500 10 20 30 40 500 10 20 30 40 50
Time (sec)
PaperCon 2011 Page 312
Fines Distribution of a Sheet Formed in a DDJ Under Continuous Mixingg
30
20
25
nt (%
)
15
s C
onte
n
5
10
Fine
s
00 0.1 0.2 0.3 0.4 0.5 0.6Wire side Thickness (mm) Top side
PaperCon 2011 Page 313
Other Drainage Testers
Moving Belt Drainage Tester Pulsed Drainage DevicePulsed Drainage Device…
PaperCon 2011 Page 314
Ultrasonic Dynamic Drainage Tester
Impeller
Vacuum Gauge
screen Impeller
Ultrasound HornVacuum Gauge
Vacuum PumpVacuum Pump
BalanceData Processing
PaperCon 2011 Page 315
Data Collection
Web SolidsWater Retention Value
ate
Time
Filtr
a
e Time
Pres
sure
Time
PaperCon 2011 Page 316
Ultrasonic Filtration Screen
Ultrasonic processor Filtration
screen
Ultrasonic filtration screenscreen
PaperCon 2011 Page 317
Screen Unblocking and Deflocculation by Ultrasound in Standard Retention Test
100
%)
60
80
ntio
n (% Control
Control + Chitosan
40
60
es R
eten
20Fine With ultrasound Ultrasound + Chitosan
00 500 1000 1500
Impeller Rotating Speed (rpm)Impeller Rotating Speed (rpm)
PaperCon 2011 Page 318
Drainage Profiles of a Newsprint FurnishAt 400 rpm with Mat Formation
400
No mixing, 14.1sUlt d 11 5
300
ht (g
)
Mixing + Ultrasound, 15.9s
Ultrasound, 11.5s
200
rate
Wei
g
Mixing, 17.0s
g
100
Filtr
00 10 20 30
Time (sec)
PaperCon 2011 Page 319
Drainage and Retention with ChitosanAt 400 rpm with Mat Formation
UltrasoundMixing at 400 rpmNo MixingSample
11.517.014.1Pulp Alone
Drainage Time (s)
11.814.112.3Pulp + Chitosan
p
Fines Retention (%)
80 987 388 6Pulp + Chitosan
64.179.777.6Pulp Alone
Fines Retention (%)
16.87.611.0Increase in Retention
80.987.388.6Pulp + Chitosan
PaperCon 2011 Page 320
Drainage Profiles of a Newsprint FurnishAt 1000 rpm with Mat Formation
400No mixing, 11.7sUltrasound, 10.0s 69.3%
300
ight
(g)
Mixing, 38.1s
53.6%
68 9%
200
ltrat
e W
e
30.9%
68.9%
Ultrasoun + Mixing, 10.7s
100
Fil
00 10 20 30 40
Time (sec)
PaperCon 2011 Page 321
Retention Is Changed by Ultrasound Intensity
90
%)
80
ntio
n (%
TMP + Chitosan
70
es R
eten
60Fin
TMP
500 20 40 60 80 100
Ultrasound Amplitude (%)Ultrasound Amplitude (%)
PaperCon 2011 Page 322
Pressure Profile under Various Turbulence Conditions
0000 10 20 30 40
a)
00 10 20 30 40
a)
-10
sure
(kPa
UltrasoundUltrasound & mixing at 1000 rpm
-10
sure
(kPa
UltrasoundUltrasound & mixing at 1000 rpm
-20
Pres No turbulence
-20
Pres No turbulence
-30
Mixing at 1000rpm
-30
Mixing at 1000rpm
-30
Time (sec)-30
Time (sec)
PaperCon 2011 Page 323
Drainage vs. Pressure and Retention
30a)
30 100100
20sure
(kPa
20
80
ion
(%)80
= 0.4505Fines Retention
R2 = 0 7587um P
ress
Equilibrium Vacuum
= 0 7587
Equilibrium Vacuum
40
60
es R
eten
ti
40
60
R2 = 0.758710
Vacu
u = 0.758710
20
40
Fine
20
40
08 10 12 14 16 18
08 10 12 14 16 18
00
Drainage Time (s)Drainage Time (s)
PaperCon 2011 Page 324
Fines Distribution of a Sheet Formed with Ultrasound
30
Under Continuous Mixing
20
25
nt (%
)
Under Continuous Mixing
15
s C
onte
n
5
10
Fine
s
With Ultrasound
00 0.1 0.2 0.3 0.4 0.5 0.6Wire side Thickness (mm) Top side
PaperCon 2011 Page 325
Drainage Mechanism with Ultrasound
Before starting drainage test
Dewatering under mixing Dewatering under ultrasound
PaperCon 2011 Page 326
Conclusions
• The turbulence induced by impellor in a conventional DDJ increases filtration resistance enormously.
• Ultrasound can Deflocculate fiber suspensionpUnblocking forming wireEnlarge dewatering channel in the web
• The Ultrasonic DDJ could be very useful laboratory tool to determine drainage under dynamic conditionsDrainage profileVacuum profileR t tiRetention
PaperCon 2011 Page 327
Acknowledgements
• T. Owston Initial experimental work
• C. Castro Data processing program
G D i G L i i T O t & M D i ill• G. Dorris, G. Laivins, T. Owston & M. Drainville Filtrate weight and pressure monitoring
• I. Tihanyi & N.VignolaI. Tihanyi & N.Vignola Vessel and accessory manufacturing
• M. Laleg, J. Jong, I. Vadeiko, T. Owston and S. Middleton Valuable discussion
• NSERC IPS program• NSERC IPS program
PaperCon 2011 Page 328