appendices appendix a dewatering aid tests - pure …

APPENDICES

APPENDIX A DEWATERING AID TESTS - PURE REAGENTS

BUCHNER VACUUM AND AIR PRESSURE FILTERS

Table 1-A Thick Cake Dewatering Results of the Vacuum Filtration Tests Conducted on the Massey-West Virginia Coal* Using Reagent TDDP Dissolved 33.3% in Diesel w/ and w/o Butanol Spray

Moisture Content (%wt)

Reagent Type Reagent Dosage (lbs/ton) TDDP TDDP + 2 lb/ton Butanol

0 25.1 22.5 1 17.4 14.2 2 15.2 12.1 3 14.8 11.4 5 14.6 10.6

* 2.5-inch diameter vacuum filter; 3 min. drying cycle time, sample size -600 µm, dense medium sample crushed, ground and floated using 1 lb/ton kerosene and 75 g/ton MIBC and cake thickness 1.36 in.

Table 2-A Results of the Vacuum Filtration Tests Conducted on the CONSOL Pittsburgh

Coal* (-500 µm) Using Reagent Span 80 Dissolved 33.3% in Diesel at 25 in.Hg Vacuum Pressure

Moisture Content (% wt.)

Cake Thickness (inch) Reagent Addition (lb./ton) 0.20 0.45 0.80

0 22.8 26.3 27.5 1 11.0 15.3 16.2 3 9.2 13.3 15.3 5 8.5 12.1 14.4

* 2.5 inch diameter filter; 2 min drying cycle time Sample floated using 1 lb/ton kerosene and 100 g/ton MIBC.

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Table 3-A Results of the Vacuum Filtration Tests Conducted on the Elkview-Canada Coal* (-500 µm) Using Metal Ions and Reagent TDDP Dissolved 33.3% in Diesel at 25 in.Hg

Reagent TDDP Moisture Content (% wt.)

Dosage Metal Ions w/ TDDP (lb./ton)

TDDP with no metal ion Al3+ (20 g/ton) Cr3+ (10 g/ton) Cu2+ (50 g/ton)

0 24.4 20.7 20.4 20.3 0.25 20.8 15.8 16.1 17.4 0.5 18.5 14.2 14.4 15.8 1 17.0 13.3 13.5 14.4 2 15.2 13.0 12.7 13.5 3 13.8 12.5 12.4 13.2 5 12.8 12.1 12.3 13.0

p H 7.5 7.5 - 5.5 7.5 - 5.5 6.5 - 4.5 *2.5 inch diameter vacuum filter; cake thickness 0.4 in; 2 min drying cycle time, and sample floated using 1 lb./ton kerosene and 100 g/ton MIBC.

Table 4-A Change in Contact Angle, Filtrate Surface Tension and Moisture Content of CONSOL Pittsburgh Clean Coal Sample* Using Polymethyl Hydrosiloxane (PMHO) (Molecular Weight 2900) Dissolved 33% in Diesel at 25 in.Hg Vacuum Pressure

Reagent Type

Reagent Dosages (lb./ton)

Contact Angle

(Degree)

Filtrate Surface Tension (µN/m)


Non 0 7 71 27.9 Kerosene 1 43 68 25.2

1 75 65 18.2 2 82 63 16.3 3 88 61 15.9

Polymethyl Hydrosiloxane

5 94 57 16.1 * 2.5 inch diameter vacuum filter; dense medium sample ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; 2 min drying cycle time; sample size –0.5 mm; cake thickness 0.45 inches; and solid content 18%.

254

Table 5-A Effects of Using a PMHO with Molecular Weight of 2900 Dissolved in Different Solvents for the Vacuum Filtration of a CONSOL Pittsburgh Coal* (0.5 mm x 0)

Cake Moisture (% wt) Reagent

Dosage (lb/ton) Diesel Kerosene Fuel Oil Gasoline Butanol None

0 26.1 26.1 26.1 26.1 26.1 26.1 1 16.8 17.3 17.6 17.8 18.3 20.4 3 15.0 15.2 15.4 15.6 17.0 19.0 5 14.8 14.7 15.2 15.2 16.4 18.3

* 2.5-inch diameter vacuum filter at 25” Hg; 2 min. drying cycle time, Dense medium product crushed in jaw and roll crusher and wet ground in ball mill. Screened at 0.5mm and underflow floated using 1 lb/ton kerosene and 75g/ton MIBC and cake thickness of 0.45in

Table 6-A Results of the Vacuum Filtration Tests Conducted on a Moss 3 Coal Sample*

Using High and Low HLB Surfactants


Reagent Types Reagent Dosage (lbs/ton)

Diamine Dodecylamine Sun Flower Oil Span 80 TDDP 0 22.6 22.6 22.6 22.6 22.6

0.5 20.6 19.1 17.1 16.5 16.9 1 20.5 18.6 16.2 15.0 15.3 2 19.7 17.9 14.3 12.6 12.2 3 19.8 17.4 13.2 11.4 11.1 5 20.9 17.1 12.6 10.9 10.2

* 2.5-inch diameter vacuum filter; at 25” Hg. 2 min. drying cycle time. Dense medium product crushed and wet ground in ball mill to minus 0.6mm and floated using 1lb/ton kerosene and 0.15lb/ton MIBC and cake thickness 0.45 in.

255

Table 7-A Butanol Spray Results of the Vacuum Filtration Tests Conducted on the Moss 3 Coal* Using Reagent Span 80 Dissolved 33.3% in Diesel


Reagent Type Reagent Dosage (lbs/ton) Span 80 S80 + 2 lb/ton Butanol

0 23.1 18.1 1 13.8 8.3 2 12.2 7.1 3 10.1 6.1 5 9.7 5.6

* 2.5-inch diameter vacuum filter; the company dens medium sample crushed, ground and floated using 1 lb/ton kerosene and 75 g/ton MIBC; 2 min. drying cycle time; Sample size -600 µm; and Cake thickness 0.4 in.

Table 8-A Blending Results of the Air Pressure Filtration Tests Conducted on the

Massey-West Virginia Coal* Using Reagent Soy Bean Oil, TDDP and Combination of two (1:1 Ratio) Dissolved 33.3% in Diesel 100 kPa Air Pressure


Reagent Type Reagent Addition (lb./ton)

Soy Bean Oil TDDP Combination 0 27.8 27.8 27.8 1 22.8 18.7 19.2 2 19.9 15.2 16.3 3 18.3 13.5 13.7 5 19.2 12.2 11.6

*2.5-inch diameter air pressure filter; 2 min. drying cycle time, sample size –1mm, and cake thickness 0.5 inches, and company sample used as it is.

256

Table 9-A Methanol Spray Results of the Vacuum Filtration Tests Conducted on the Toms Creek Coal* Using Reagent Span 80 (Dissolved 33.3% in Diesel) at 25 in.Hg vacuum pressure


Reagent Type Reagent Dosage (lbs/ton) Span 80 Span 80

+ Methanol Spray 0 29.7 24.8 1 22.1 20.2 2 17.3 15.1 3 15.8 13.2 5 16.4 13.0

* 2.5-inch diameter Buchaner vacuum filter; the company sample used as it is; 2 min. drying cycle time; sample size – 0.15 mm; solid content 13.7%; and cake thick 0.4 in.

Table 10-A Carrier solvent effects of TDDP (dissolved 1:2 ratio) conducted on

Middle Fork coal sample* at 25 in Hg vacuum pressure


Carrier Solvents in TDDP Reagent Addition (lb./ton)

Butanol Butanol+Diesel Diesel 0 23.1 23.1 23.1 1 20.1 17.3 14.2 2 19.7 15.2 12.4 3 18.0 13.7 11.0 5 18.2 14.1 10.5

* 2.5-inch Buchaner vacuum pressure filter; the dens medium sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; 2 min. drying cycle time; sample size 28 mesh x 0; cake thickness 0.45 in.; and solid content of sample 22.6%.

257

Table 11-A Dewatering tests results of Span 80 (33.3% in diesel) conducted on Red River clean and ultra clean coal sample* at 25 in.Hg vacuum pressure

Moisture Content (%wt) Reagent

Dosage (lbs/ton)

1Clean Coal 2Ultra Clean Coal 0 28.6 23.0 1 20.3 17.7 2 20.1 14.4 3 19.1 12.9 5 19.6 12.0

* 2.5-inch diameter Buchaner vacuum filter; the company sample floated using 400 g/ton kerosene and 100 g/ton MIBC; sample size 28 mesh x 0; solid content 15.2%; and cake thick 0.4 in. 1 company coal floated once in conventional pilot flotation cell and has higher clay content; 2 company sample floated in lab cell and cleaned twice has clay content.

Table 12-A Temperature effects of pure Ethylglycol Monooleate (EGMO)

conducted on Middle Fork coal sample* at 25 in Hg vacuum pressure


Temperature (°C) Reagent Addition (lb./ton)

20 40 60 0 23.4 20.1 18.0 1 18.6 15.5 13.2 2 16.5 13.7 11.5 3 16.4 13.2 10.8 5 14.7 11.8 10.7 7 14.3 11.7 10.5

* 2.5-inch Buchaner vacuum pressure filter; the dens medium sample1 crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; 2 min. drying cycle time; sample size 28 mesh x 0; cake thickness 0.43 in.; and solid content of sample 17.3%.

258

Table 13-A Methanol Spray Results of the Vacuum Filtration Tests Conducted on the Toms Creek Coal* Using Reagent TDDP (Dissolved 33.3% in Diesel) at 25 in.Hg vacuum pressure


Reagent Type Reagent Dosage (lbs/ton) TDDP TDDP + Methanol Spray

0 28.1 24.9 1 20.8 18.2 2 17.2 15.3 3 15.8 13.1 5 15.9 12.8

* 2.5-inch diameter Buchaner vacuum filter; the company sample used as it is; 2 min. drying cycle time; sample size – 0.15 mm; solid content 13.7%; and cake thickness 0.4 in.

Table 14-A Time effects of PMHO (33.3% in diesel) conducted on Massey-West Virginia coal sample* at 25 in Hg vacuum pressure


Time Reagent Addition (lb./ton)

Fresh Coal 10 Days Old 20 Days Old 0 22.6 24.7 27.2 1 17.3 19.4 28.8 2 16.1 17.3 25.6 3 15.7 16.5 20.4 5 15.3 16.2 18.6

* 2.5-inch Buchaner vacuum pressure filter; the company sample (flotation+spiral) used; 2 min. drying cycle time; sample size –1 mm; cake thickness 0.45 in.; and solid content of sample 22.6%.

259

Table 15-A Effect of 1pure ethyl oleat, (E. oleat) dissolved 50% and 33.3% in diesel conducted on Middle Fork Coal Sample* at 25 inHg Vacuum Pressure

Moisture Content (% wt.) Reagent

Addition (lb./ton) Pure Ethyl Oleat E. Oleat (50% in

Diesel) E. Oleat (33.3% in

Diesel) 0 22.7 22.7 22.7 1 17.2 15.3 13.9 2 15.8 12.9 11.2 3 14.1 11.0 10.3 5 13.1 10.7 9.8

* 2.5-inch diameter vacuum filter; solid content 47.9%; 60 minutes conditioning time; 2 min. drying cycle time; sample size 0.85 x 0 mm; dens medium coal crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton; and cake thickness 0.43 in. 1Higher solid content and longer conditioning time gives better results for pure ethyl oleat.

Table 16-A Results of the air pressure filtration tests conducted on the West Virginia

Coal* using Reagent TDDP dissolved 25% in diesel

Moisture Content(% wt.) Cake Thickness (inch)

Applied Pressure

(kPa)

Reagent Addition (lb./ton) 0.32 0.63

0 32.0 35.6 1 17.1 19.2 2 15.0 17.4 3 13.5 17.2

100

5 12.4 16.7 0 28.5 33.8 1 13.7 17.3 2 10.5 15.0 3 9.2 13.3

200

5 7.8 11.6 * 2.5-inch diameter pressure filter; the company sample used as it is; 2 min. drying cycle time; sample size –1.2 mm; cake thickness 0.4 in.; and solid content of sample 19.6%.

260

Table 17-A Results of the vacuum filtration tests conducted on the West Virginia Coal* using Reagent TDDP dissolved 33.3% in diesel at 25 in.Hg vacuum pressure


Cake Thickness (inch) Reagent Addition (lb./ton) 0.3 0.6

0 25.5 27.2 1 16.9 19.3 2 14.8 18.2 3 13.3 17.8 5 14.5 18.3

* 2.5-inch diameter Buchaner vacuum filter; the company sample used as it is; 2 min. drying cycle time; sample size –1.2 mm; cake thickness 0.4 in.; and solid content of sample 19.6%.

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APPENDIX B DEWATERING AID TESTS - LIPID REAGENTS


Table 1-B Results of the Vacuum Filtration Tests Conducted on the Pittsburgh-USA Coal* (-500 µm) Using Reagent Soy Bean Oil (SBO) Dissolved 33.3% in Diesel at 25 in Hg Vacuum Pressure


Cake Thickness (inch) Reagent Addition (lb./ton) 0.2 0.4 0.80

0 22.8 25.1 27.2 1 14.2 16.8 17.6 3 11.4 14.3 16.0 5 11.3 13.7 15.6

* 2.5 inch diameter filter; 2 min drying cycle time and sample floated using 1 lb/ton kerosene and 100 g/ton MIBC.

Table 2-B Results of the Vacuum Filtration Tests Conducted on the Pittsburgh-

USA Coal* Using Reagent Peanut Oil Dissolved 33.3% in Diesel at 25 in.Hg Vacuum Pressure

Moisture Content (%wt) Cake Thickness (inch)

Reagent Addition (lb./ton) 0.2 0.4 0.80

0 23.2 25.6 26.7 1 13.7 16.4 17.3 3 12.4 14.9 16.6 5 11.8 14.4 16.2

* 2.5 inch diameter vacuum filter; the dens medium company sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; 2 min drying cycle time; and sample size –0.5 mm

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Table 3-B Results of the Pressure Filtration Tests Conducted on the Peak Down-Australia Coal Sample* Using Reagent Corn Oil Dissolved 33.3% in Diesel


Cake Thickness (inch) Applied Pressure

(kPa)

Reagent Addition (lb./ton)

0.2 0.4 0.8 0 26.2 28.2 28.7 1 17.8 21.4 22.6 3 16.0 19.2 20.4

100

5 15.4 18.4 19.3 0 23.2 25.5 27.3 1 14.2 16.8 20.1 3 12.7 14.7 18.2

200

5 11.8 14.2 17.4 * 2.5-inch diameter pressure filter; the company sample ground 1.5 min. and re-floated using 1 lb/ton kerosene and 75 g/ton MIBC; 2 min. drying cycle time, sample size 28 mesh x 0.

Table 4-B Effect of Esterified1 Crisco Oil and Lard Oil on Dewatering of Moss 3

Coal Sample* (1 mm x 0) at 25 in Hg vacuum pressure

Reagent Dosage (lbs/ton)


Crisco Oil Lard Oil

0 19.7 19.7 1 13.3 12.4 2 11.4 11.2 3 10.4 9.4 5 9.8 9.0 7 8.0 7.9

*2.5-inch diameter vacuum filter; 2 min. drying cycle time, Dense medium product wet ground in ball mill to 1 mm and floated using 1 lb/ton kerosene and 100g/ton MIBC and cake thick 0.41in. Flotation product 15.9 % solids

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Table 5-B Effects of Combining the Techniques of Using Sunflower Oil and Butanol Spray to Achieve Deep Moisture Reductions at 1.4-inch Cake Thickness of Moss 3 coal*

Moisture Content (%wt) Reagent

Dosage (lbs/ton) No Spray Butanol Spray

0 25.8 22.5 1 19.6 16.5 2 17.4 14.2 3 16.5 13.0 5 15.8 12.7

* 2.5-inch diameter vacuum filter at 25” Hg; 2 min. drying cycle time, Dense medium product crushed in jaw and roll crusher and wet ground in ball mill. Screened at 0.6mm and underflow floated using 1 lb/ton kerosene and 0.15lb/ton MIBC and cake thickness of 1.4in

Table 6-B Effects of Using PM.CH in a Mixed Diesel Oil-Soybean Oil Solvent for

the Filtration of a Massey Bituminous Coal* (0.5 mm x 0) at 0.5-inch Cake Thickness


Reagent Type Reagent Addition (lb./ton)

Soy Bean Oil Polymethyl Hydrosiloxane Combination

0 27.5 27.5 27.5 1 22.6 21.5 20.8 2 21.0 20.4 18.5 3 20.3 19.6 16.7 5 20.7 19.8 14.2

*2.5-inch diameter vacuum filter at 25” Hg. 2 min drying cycle time. Sample received as a froth flotation product (0.5mm x 0). Cake thickness 0.5in.

264

Table 7-B Blending results of the pressure filter tests conducted on Middle Fork coal sample* using reagent corn oil, TDDP and blending of them (1:1 ratio) dissolved 33.3% in diesel at 150 kPa air pressure


Reagent Type Applied Pressure

(kPa)

Reagent Addition (lb./ton)

Corn Oil TDDP Corn Oil+TDDP 0 26.1 26.1 26.1 1 17.3 13.7 13.9 2 14.9 10.6 10.1 3 13.5 9.5 8.8

150

5 13.2 9.1 8.5 * 2.5-inch diameter pressure filter; the dens medium coal sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; 2 min. drying cycle time; sample size –0.85 mm; cake thickness 0.45 in.; and solid content of sample 19.6%.

Table 8-B Time effects of Fish Oil (33.3% in diesel) conducted on Massey-West

Virginia coal sample* at 25 in Hg vacuum pressure


Time Reagent Addition (lb./ton)

Fresh Coal 10 Days Old 20 Days Old 0 23.1 24.5 26.2 1 18.9 23.1 25.3 2 16.8 19.6 22.1 3 15.3 17.3 19.3 5 14.7 15.5 17.3

* 2.5-inch Buchaner vacuum pressure filter; the company sample (flotation+spiral) used; 2 min. drying cycle time; sample size –1 mm; cake thickness 0.45 in.; and solid content of sample 22.6%.

265

Table 9-B Dewatering results of oxidized, high clay content, contaminated, and high water hardness Massey coal sample* at 25 in Hg Vacuum Pressure


Addition (lb./ton) Diesel Lard Oil Fish Oil PMHO EGMO Span

80 TDDP

0 24.3 24.3 24.3 24.3 24.3 24.3 24.3 1 24.7 21.6 26.7 25.3 25.6 24.9 23.0 2 26.3 19.9 24.5 27.2 20.7 19.8 19.6 3 28.2 18.6 20.3 28.6 18.4 17.4 17.4 5 30.8 23.4 19.1 29.1 18.6 17.1 16.9

* 2.5-inch diameter Buchaner vacuum filter; the 30 days old company sample used as it is; sample size –1.7; 2 min. drying cycle time; cake thick 0.45 in.; and solid content 23.6%.

Table 10-B Results of the Vacuum Filtration Tests Conducted on S. Korean

Anthracite Sample* Using Span 80, Fish Oil and SFO Dissolved 33.3% in Diesel at 25 in.Hg Vacuum Pressure


Reagent Type Reagent Addition (lb./ton) SFO Fish Oil Span 80

0 19.6 19.6 19.6 1 15.0 14.3 13.7 2 12.5 12.1 11.3 3 11.1 10.2 10.0 5 9.6 10.5 9.4

* 2.5 inch diameter Buchner filter; size -500 µm; 2 min drying cycle time; cake thickness 0.41 in.; ash content 7.8%; and anthracite sample screened and floated using 1 lb/ton kerosene and 100 g/ton MIBC.

266

APPENDIX C DEWATERING AID TESTS - MODIFIED LIPID REAGENTS


Table 1-C Results of the Filtration Tests Conducted on a 0.5 mm x 0 Australian Coal Sample* Using a Modified Lard Oil

Cake Moisture (% wt)

Lard Oil w/o Diesel w/ Diesel

Reagent Dosage

(lbs/ton)1 Un- modified Modified Un-modified Modified

Ethanol Diesel

0 22.4 22.4 22.4 22.4 22.4 22.4 1 19.0 17.7 17.1 16.4 20.5 19.9 3 16.0 15.8 15.2 13.44 19.1 18.1 6 15.4 15.6 13.8 11.5 18.6 17.9 9 15.3 15.0 12.8 10.4 18.7 18.7 15 14.9 15.3 12.2 9.9 18.4 19.0

*2.5-inch diameter vacuum filter; 3 min. drying cycle time, sample size 0.5mmx0, wet ground in ball mill and floated using 1 lb/ton kerosene and 0.2 lb/ton MIBC and cake thick 0.42 in. Flotation product 16.2 % solids

Table 2-C Results of the Filtration Tests Conducted on a 0.5 mm x 0 Moss 3 Coal

Sample* Using a Modified Fish Oil

Moisture Content (%wt) Fish Oil

Reagent Dosage (lbs/ton) Un-

Modified Modified

0 20.0 20.0 1 14.5 11.2 2 12.8 10.5 3 12.1 10.1 5 13.1 10.0

* 2.5-inch diameter vacuum filter; 2 min. drying cycle time, Dense medium product wet ground in ball mill and floated using 1 lb/ton kerosene and 100g/ton MIBC and cake thick 0.4 –0.5 in. Flotation product 16.1 % solids

267

Table 3-C Dewatering results of ethanol, diesel, lard oil and esterified lard oil conducted on SGS-Australia coal sample* at 25 inHg Vacuum Pressure


Addition (lb./ton) Ethanol Diesel Pure Lard Oil

Pure Lard Oil (33.3% in

diesel)

Esterified Lard Oil (33.3% in diesel)

0 22.0 20.1 22.31 22.3 22.4 1 20.5 19.9 19.0 17.1 16.4 3 19.1 18.1 16.0 15.2 13.4 6 18.6 17.9 15.4 13.8 11.5 9 18.7 18.9 15.3 12.8 10.4 15 18.4 19.0 14.9 12.2 9.9

* 2.5-inch diameter Buchaner vacuum filter; the mixed sample (flotation and spiral product) ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; sample size 28 mesh x 0; 2 min. drying cycle time; cake thick 0.42 in.; and solid contnet 16.4%. Lard oil esterified by 1 mole of lard fat, 3 mole ethanol, and 2.5% by volume acetic acid on a hot plate.

Table 4-C Dewatering results of butanol, diesel, coconut oil and esterified coconut oil conducted on Middle Fork coal sample* at 25 inHg Vacuum Pressure


Addition (lb./ton) Butanol Diesel Pure Coconut

Oil

Pure Coconut Oil (33.3% in

diesel)

Esterified Coconut Oil (33.3% in

diesel) 0 21.5 21.3 21.5 21.3 21.5 1 19.3 17.6 17.1 16.7 15.8 3 18.9 18.5 16.0 15.4 13.3 6 18.9 18.4 15.4 13.6 12.2 9 19.0 18.7 15.0 13.5 11.3 15 18.9 17.5 14.9 12.6 10.2

* 2.5-inch diameter Buchaner vacuum filter; the dens medium sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; sample size 28 mesh x 0; 2 min. drying cycle time; cake thick 0.41 in.; and solid content 16.4%. Coconut oil esterified by 1 mole of coconut fat, 3 mole butanol, and 2.5% by volume acetic acid on a hot plate.

268

Table 5-C Esterification Effect of Lard Oil (33.3% in diesel) on dewatering of Meadow River-West Virginia Coal* at 25 inHg Vacuum Pressure


Addition (lb./ton) Lard Oil Processed Lard Oil

0 23.2 23.2 1 17.2 14.2 2 15.4 11.8 3 14.5 10.9 5 14.1 10.4

* 2.5-inch diameter vacuum filter; 2 min. drying cycle time; particle size 0.5 x 0 mm; cake thick 0.43 in.; the dens medium coal crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton; and cake thickness 0.43 in. The processed Lard oil obtained using 1 mole lard fat; 3 moles methanol and 2.5% by volume acetic acid on a hot plate.

269

APPENDIX D DEWATERING AID TESTS - DRUM FILTER TEST DATA

Table 1-D West Tech Drum filter results on dewatering of Middle Fork coal sample* by using Span 80 (33.3% in diesel), 20 g/ton Al ion and Butanol Spray at 25 in Hg Vacuum Pressures


Addition (lb./ton) Span 80 Span 80 +

Al ion

Span 80 +Al ion+Butanol

Spray 0 27.5 24.5 21.4

0.5 22.3 18.6 16.4 1 20.1 16.3 14.1 2 18.2 15.7 13.2 3 16.2 15.2 12.1 5 15.2 14.6 11.8

* 3.5 inch drum filter used for the tests; dense medium coal sample crushed, ground and floated by using 450 g/ton kerosene and 100 g/ton MIBC; particle size 0.5 mm x 0; 2 min. drying cycle time; cake thickness 0.42 in.; solid content 17.1%; conditioning time for Al ion 5 min.

Table 2-D Drum filter test result on dewatering of Elkview clean coal sample* by

using Span 80 (33.3% in diesel) at 22 in Hg Vacuum Pressure

Moisture Content (% wt.) Reagent Addition (lb./ton) Span 80 Span 80 + Ethanol

Spray 0 20.3 17.9 1 15.2 14.5 2 12.3 11.6 3 10.4 9.3 5 10.7 9.5

*10 inches diameter drum filter used for the tests; Vacuum 22 inches Hg; 2 min. drying cycle time; particle size 14 mesh x 0; Slurry sample received from Elkview. Water-only cyclone/flotation product combined-solids content 50%. Sample diluted by adding water and used in the tests; cake thickness 0.35 - 0.45 in, solid content 17.2%.

270

Table 3-D Drum filter test result on dewatering of Elkview clean coal sample* by using EGMO (33.3% in diesel) at 22 in Hg Vacuum Pressure


Addition (lb./ton) EGMO EGMO + Ethanol

Spray 0 17.2 15.5 1 12.8 12.0 2 10.5 9.6 3 9.1 8.3 5 8.1 7.7

* 10 inches diameter drum filter used for the tests; Vacuum 22 inches Hg; 2 min. drying cycle time; particle size 14 mesh x 0; Slurry sample received from Elkview. Water-only cyclone/flotation product combined-solids content 50%. Sample diluted by adding water and used in the tests; cake thickness 0.2 - 0.3 in, solid content 17.2%.

271

APPENDIX E DEWATERING AID TESTS - HORIZONTAL BELT FILTER TEST DATA

Table 1-E Belt filter test result on dewatering of Elkview clean coal* showing effect of Ethanol spray and using principal reagent Span 80 (33.3% in diesel) at 18-22 in Hg Vacuum Pressure


Addition (lb./ton) Span 80 Span 80 + Ethanol

Spray 0 19.5 17.8 1 15.2 13.0 2 13.8 12.6 3 12.1 10.8 5 10.9 9.4

* Horizontal belt filter dimensions: 1.5m length and 10 cm width. Slurry sample received from Elkview. Water-only cyclone/flotation product combined-solids content 50%. Sample diluted for test. 2 min. drying cycle time; particle size 14 mesh x 0; cake thickness 0.4 - 0.5 in, solid content 27.1%.

Table 2-E Belt filter test result on dewatering of Elkview clean coal* showing

effect of Ethanol spray and using principal reagent Esterified lard oil (33.3% in diesel) at 18-22 in Hg Vacuum Pressure


Addition (lb./ton) Esterified lard oil Esterified lard oil

+ Ethanol Spray 0 23.7 21.9 1 17.2 15.7 2 15.7 14.7 3 14.3 13.9 5 17.6 16.9

* Horizontal belt filter dimensions: 1.5m length and 10 cm width. Slurry sample received from Elkview. Water-only cyclone/flotation product combined-solids content 50%. Sample diluted for test. 2 min. drying cycle time; particle size 14 mesh x 0; cake thickness 0.4 - 0.5 in, solid content 22.8%.

272

Table 3-E Belt filter test result on dewatering of Elkview clean coal* showing effect of Ethanol spray and using principal reagent TDDP (33.3% in diesel) at 18-22 in Hg Vacuum Pressure


Addition (lb./ton) TDDP TDDP

+ Ethanol Spray 0 16.8 15.7 1 12.4 11.5 2 10.4 9.5 3 9.1 8.3 5 8.4 7.9

* Horizontal belt filter dimensions:1.5 m length and 10 cm width.Slurry sample received from Elkview. Water-only cyclone/flotation product combined-solids content 50%. Sample diluted for test. 2 min. drying cycle time; particle size 14 mesh x 0; cake thickness 0.4 - 0.5 in, solid content 17.1%.

Table 4-E Belt filter test result on dewatering of Red River coal sample* by using

Span 80 (33.3% in diesel) at 18-22 in Hg Vacuum Pressure

Moisture Content (% wt.) Reagent Addition (lb./ton) Span 80 Span 80

+ Ethanol Spray 0 20.7 19.3 1 16.6 15.9 2 14.3 13.2 3 12.2 11.4 5 10.6 10.1

* Horizontal belt filter dimensions:1.5 m length and 10 cm width2 min. drying cycle time; particle size 28 mesh x 0; Dense medium cyclone clean coal sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; cake thickness 0.4 - 0.5 in, solid content 24.64%.

273

Table 5-E Belt filter test result on dewatering of Red River coal sample* by using Esterified lard oil (33.3% in diesel) at 18-22 in Hg Vacuum Pressure



+ Ethanol Spray 0 18.2 17.1 1 14.8 13.4 2 12.9 11.8 3 11.1 10.3 5 10.1 9.7

* Horizontal belt filter dimensions: 1.5m length and 10 cm width. 2 min. drying cycle time; particle size 28 mesh x 0; Dense medium cyclone clean coal sample crushed, ground and floated using 1 lb/ton kerosene and 100 g/ton MIBC; cake thickness 0.3-0.4 in.

274

APPENDIX F DEWATERING AID TESTS - DISC FILTER TEST DATA

Table 1-F Disc filter test result on dewatering of Moss 3 coal sample* by using EGMO (33.3% in diesel) at 24/19 in Hg Vacuum Pressure


Addition (lb./ton) EGMO EGMO

+ Ethanol Spray 0 30.4 27.4 1 24.6 22.8 2 21.0 19.6 3 19.3 18.4 5 18.8 17.5

* One filter leaf used for the test; top and bottom vacuum used 24/24 and 24/19 in Hg; 2 min. drying cycle time; particle size 28 mesh x 0; Dense medium cyclone clean coal sample crushed, ground and floated by using 1 lb/ton kerosene and 100 g/ton MIBC; cake thickness 0.4 in, solid content 16.6%.

Table 2-F Disc filter test result on dewatering of Moss 3 coal sample* by using Esterified lard oil (33.3% in diesel) at 24/19 in Hg Vacuum Pressure



+ Ethanol Spray 0 27.6 23.5 1 23.5 17.1 2 22.9 16.9 3 21.8 16.1 5 19.6 15.6

* One filter leaf used for the tests; top and bottom vacuum used 24/24 and 24/19 in Hg; 2 min. drying cycle time; particle size 28 mesh x 0; ; Dense medium cyclone clean coal sample crushed, ground and floated by using 1 lb/ton kerosene and 100 g/ton MIBC; cake thickness 0.4 in, solid content 16.6%.

275

APPENDIX G DEWATERING AID TESTS - NOVEL CENTRIFUGE TEST DATA

Table 1-G Centrifuge Filtration Results Conducted on Middle Fork-Virginia Clean Coal Sample* in the Basket Using Air Pressure at 2500 G-Force

Cake Moisture (%wt)

w/ Air Pressure (kPa) Spin Time (sec) w/o

Air 100 200 300 0 39.1 39.1 39.1 39.1 30 31.7 23.8 20.7 19.3 60 31.2 22.0 18.9 17.3 90 31.1 20.3 17.7 15.8 120 31.0 20.1 16.4 13.5 150 30.9 19.6 15.7 12.2

* 3.5 inches-diameter centrifuge basket with filter cloth attached to the basket; The sample was received as a slurry and was thickened to approximately 60-70% solids; particle size – 0.3 mm; cake thickness 0.42 in

Table 2-G Centrifugal Filtration Tests Conducted on SGS-Australia Coal

Sample* Using Air Pressure at 1500 G-Force

Cake Moisture (%wt) Air Pressure (kPa) Spin Time

(sec) None 100 200

0 42.9 42.9 42.9 30 30.1 17.3 13.9 60 28.4 16.4 12.2 90 28.3 13.9 11.1 120 28.1 13.0 9.3

* 3.5 inches-diameter centrifuge basket with filter cloth attached to the basket; The sample was received as a slurry and was thickened to approximately 60-70% solids; particle size –2mm; cake thickness 0.5

276

Table 3-G Centrifugal test results of Elkview coal sample* using Fish oil, 100 kPa air pressures at 1500 G-force

Cake Moisture (%wt)

Spin Time (sec) No air Air Air + 2 lb/ton

Fish oil Air + 4 lb/ton

Fish oil

0 38.2 38.2 38.2 38.2 30 28.1 19.0 17.0 16.3 60 27.3 17.8 16.0 15.2 90 26.7 17.6 15.1 14.2 120 26.6 16.7 14.4 14.0

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; RG dissolved 20% in butanol; Slurry sample used after the sample thickened; sample size –1 mm; conditioning time 5 min.; and cake thickness 0.5 in.

Table 4-G Centrifugal filtration test results conducted on thin cake of Pittsburgh

coal sample* (–1 mm) using air pressure at 1500 G-Force

Moisture Content (%) Air Pressure (kPa) Spin Time

(sec) No Air 100 200 300

0 33.7 33.7 33.7 33.7 30 24.3 15.7 13.6 12.1 60 23.9 14.5 12.4 10.3 90 23.4 14.1 11.1 9.3 120 23.2 13.4 10.4 8.4 150 23.1 13.0 9.2 8.2

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample used after the sample thickened; cake thickness 0.4 in.

277

Table 5-G Centrifugal filtration test results conducted on thick cake of Pittsburgh coal sample* (–1 mm) using air pressure at 1500 G-Force

Moisture Content (%)

Air Pressure (kPa) Spin Time (sec) No

Air 100 200 300 0 33.7 33.7 33.7 33.7 30 23.9 16.2 15.1 14.4 60 22.6 14.9 13.3 11.9 90 22.2 14.3 11.6 11.0 120 22.2 13.9 10.9 10.1 150 22.1 13.5 10.3 9.8



coal sample* (–1 mm) using air pressure at 2500 G-Force

Moisture Content (%) Air Pressure (kPa) Spin Time

(sec) No Air 100 200 300

0 33.7 33.7 33.7 33.7 30 22.2 14.1 12.3 11.2 60 21.1 12.4 11.0 10.0 90 20.9 12.0 10.4 9.0 120 20.4 10.9 9.4 8.2 150 20.0 10.3 9.1 7.9


278

Table 7-G Centrifugal filtration test results conducted on thick cake of Pittsburgh coal sample* (–1 mm) using air pressure at 2500 G-Force



Air 100 200 300 0 33.7 33.7 33.7 33.7 30 21.9 15.2 13.9 13.4 60 20.7 13.7 12.2 11.0 90 20.2 12.8 11.5 10.3 120 20.0 11.6 10.5 9.5 150 19.9 11.2 9.8 9.0



screened coal sample* (–1+0.074 mm) using air pressure at 1500 G-Force



Air 50 100 200 0 38.5 38.5 38.5 38.5 30 13.7 7.1 6.6 6.1 60 13.5 6.4 6.1 5.8 90 13.1 6.0 5.5 4.9 120 12.3 5.7 4.3 2.9 150 12.1 5.2 4.0 2.8

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample screened and used after the sample thickened; cake thickness 0.5 in.

279

Table 9-G Centrifugal filtration test results conducted on thick cake of Pittsburgh screened coal sample* (–1+0.074 mm) using air pressure at 1500 G-Force



Air 50 100 200 0 38.5 38.5 38.5 38.5 30 13.5 7.7 7.0 6.5 60 12.8 6.9 6.6 5.9 90 12.4 6.5 6.0 4.3 120 12.1 6.3 5.5 3.6 150 12.1 6.1 4.9 3.3



screened coal sample* (–1+0.074 mm) using air pressure at 2500 G-Force



Air 50 100 200 0 38.5 38.5 38.5 38.5 30 11.7 6.7 6.2 6.1 60 11.3 6.0 5.3 4.5 90 10.6 5.8 5.1 4.0 120 10.6 5.2 4.0 3.2 150 10.5 5.0 3.5 2.7


280

Table 11-G Centrifugal filtration test results conducted on thick cake of Pittsburgh screened coal sample* (–1+0.074 mm) using air pressure at 2500 G-Force



Air 50 100 200 0 38.5 38.5 38.5 38.5 30 11.9 6.7 6.4 6.3 60 11.2 6.6 5.4 5.6 90 10.8 5.6 5.3 4.4 120 10.5 4.9 4.3 4.0 150 10.4 4.3 4.0 3.3



screened coal sample* (–0.074 mm) using air pressure at 1500 G-Force



Air 100 200 300 400 0 42.3 42.3 42.3 42.3 42.3 30 37.7 32.4 28.1 25.4 23.0 60 37.3 31.0 25.4 22.1 20.8 90 37.0 30.5 24.5 20.9 18.8 120 36.8 30.1 23.9 20.0 18.4 150 36.8 29.6 23.4 19.6 17.9

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample screened and lower size used after the sample thickened; cake thickness 0.4 in.

281

Table 13-G Centrifugal filtration test results conducted on thick cake of Pittsburgh screened coal sample* (–0.074 mm) using air pressure at 1500 G-Force



Air 100 200 300 400 0 42.3 42.3 42.3 42.3 42.3 30 37.8 33.6 29.4 27.0 24.6 60 37.2 32.0 26.9 24.2 22.5 90 37.1 31.5 25.1 22.7 20.9 120 36.6 30.9 24.6 21.4 19.9 150 36.6 30.1 24.4 21.0 19.3



screened coal sample* (–0.074 mm) using air pressure at 2500 G-Force



Air 100 200 300 400 0 42.3 42.3 42.3 42.3 42.3 30 36.8 31.6 27.1 24.2 22.1 60 36.5 30.8 24.0 20.6 19.2 90 36.3 29.9 23.2 19.73 18.0 120 36.1 29.2 22.8 18.6 17.3 150 35.9 28.0 22.1 18.2 16.8


282

Table 15-G Centrifugal filtration test results conducted on thick cake of Pittsburgh screened coal sample* (–0.074 mm) using air pressure at 2500 G-Force



Air 100 200 300 400 0 42.3 42.3 42.3 42.3 42.3 30 36.9 33.1 27.9 24.8 23.2 60 36.4 30.9 25.4 22.5 20.6 90 36.12 30.0 23.5 21.0 19.1 120 36.0 29.2 23.1 19.9 18.2 150 36.7 28.5 22.4 19.4 17.7


Table 16-G Centrifuge Filtration Tests Results Conducted on Middle Fork-Virginia

Screened Coal Sample* Using Air Pressure at 1500 G-Force

Cake Moisture (%wt) w/ Air Pressure (kPa) Spin Time

(sec) w/o Air 50 150 250

0 39.0 39.0 39.0 39.0 30 33.3 28.8 23.6 21.6 60 33.2 27.9 22.3 20.2 90 33.0 27.1 20.5 18.6 120 32.8 26.8 19.6 16.6 150 32.8 26.2 18.6 16.3

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample used after the sample thickened; size – 0.3 mm; cake thickness 0.42 in.

283

Table 17-G Centrifuge Filtration Tests Results Conducted on Middle Fork-Virginia Screened Coal Sample* Using Air Pressure at 2500 G-Force

Cake Moisture (%wt)

w/ Air Pressure (kPa) Spin Time (sec) w/o

Air 50 150 250 0 39.0 39.0 39.0 39.0

30 31.7 27.2 22.0 20.0 60 31.2 25.6 20.4 18.2 90 31.1 25.1 19.1 17.0 120 31.0 24.9 17.8 14.9 150 30.9 24.6 17.2 14.5

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample used after the sample thickened; size – 0.3 mm; cake thickness 0.42 in.

Table 18-G Centrifugal test results of Massey - West Virginia coal sample* using Reagent

TDDP (dissolved 33.3% in diesel) at 2000 G-Force

Cake Moisture (%) Reagent TDDP (lb/ton) Spin Time

(sec) No Reagent 1 2 3

0 36.5 35.8 35.6 35.4 30 24.6 21.1 19.1 17.5 60 22.7 18.7 17.7 16.7 90 22.1 17.5 16.8 15.8 120 21.8 17.2 16.0 15.5

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; flotation and spiral sample mixed by 2:1 ratio and used after the sample thickened; size –1.7 mm; and cake thickness 0.6 in.

284

Table 19-G Centrifugal test results of Massey-West Virginia coal sample* in the basket at 2000 G-Force and air pressure

Cake Moisture (%)

Air Pressure (kPa) Spin Time (sec) w/o

Air 100 200 300 0 36.5 35.8 35.6 35.4 15 25.2 14.7 12.3 10.2 30 23.1 12.7 10.2 9.4 60 22.5 11.7 9.6 8.5 120 22.3 11.1 9.3 8.2

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; flotation and spiral sample mixed by 2:1 ratio and used after the sample thickened; size –1.7 mm; and cake thickness 0.5 in. Table 20-G Centrifugal test results of Massey-West Virginia coal sample* using Reagent

TDDP (33.3% in diesel) and air pressures at 2000 G-Force

Cake Moisture (%) Air Pressure and 1 lb/ton TDDP Spin Time

(sec) No Air

No Air 1 lb/ton TDDP

100 (kPa) 200 (kPa) 300 (kPa)

0 36.5 35.8 35.8 35.8 35.8 15 25.2 21.5 10.2 9.1 8.5 30 23.1 18.4 9.4 7.6 6.6 60 22.5 17.6 8.8 6.3 5.5 120 22.3 16.9 8.5 6.1 5.3

*3.5 inches-diameter centrifuge basket; filter cloth used in the basket; flotation and spiral sample mixed by 2:1 ratio and used after the sample thickened; size –1.7 mm; and cake thickness 0.5 in.

285

Table 21-G Centrifugal test results of Elkview- British Columbia coal sample* using Fish oil (dissolved 20 in butanol) at 2000 G-Force

Cake Moisture (%)

Fish Oil (lb/ton) Spin Time (sec) No

Reagent 1 2 4 0 38.2 38.2 38.2 38.2 30 26.9 25.4 24.9 24.5 60 26.2 24.7 23.8 23.4 90 25.6 24.0 23.2 22.7 120 25.3 23.6 22.9 22.3

* 3.5 inches-diameter centrifuge basket; filter cloth used in the basket; company sample used as it is after the sample thickened; size –1 mm; and cake thickness 0.5 in.

Table 22-G Centrifugal test results of Middle Fork-Virginia coal sample* using Reagent Span 80 (20 % in butanol) and 150 kPa air pressures at 2500 G-Force

Cake Moisture (%)

150 kPa Air Pressure and Reagent Span 80 Spin Time (sec) No

Air Air Pressure

150 kPa 1 2 4 0 39.0 39.0 39.0 39.0 39.0 30 29.0 18.0 17.1 16.6 15.7 60 27.8 16.1 15.5 15.1 13.8 90 27.2 14.6 13.8 13.2 12.4 120 26.8 14.1 13.4 12.9 12.1

*3.5 inches-diameter centrifuge basket; filter cloth used in the basket; microcel flotation product used after the sample thickened; size –0.3 mm; and cake thickness 0.5 in.

286

Table 23-G Centrifuge test results conducted on Middle Fork-Virginia clean coal sample* using air pressures at 2000 G-Force

Cake Moisture Content (%)

Air Pressure (kPa) Spin Time (sec)

No Air 50 100 200 250

0 39.0 39.0 39.0 39.0 39.0 30 32.3 27.9 23.5 20.0 19.2 60 32.1 26.7 21.8 18.5 18.0 90 32.1 26.1 20.8 17.3 16.5 120 32.0 25.5 19.8 15.4 14.7 150 31.9 25.0 19.0 14.7 13.9


Table 24-G Centrifuge test results conducted on the screened over size Middle Fork-

Virginia clean coal sample* using air pressures at 2000 G-Force

Cake Moisture Content (%) Air Pressure (kPa)

Spin Time (sec)

No Air 50 100 200 250

0 41.1 41.1 41.1 41.1 41.1 30 28.5 12.5 11.5 9.2 8.5 60 28.0 10.2 9.9 7.6 7.0 90 27.6 9.5 8.5 5.8 5.1 120 26.8 8.5 7.3 3.7 3.5 150 26.6 8.1 7.0 3.4 3.2

*3.5 inches-diameter centrifuge basket; filter cloth used in the basket; microcel flotation product used after the sample thickened; size –0.3+0.038 mm; and cake thickness 0.4 in.

287

Table 25-G Centrifuge test results conducted on the screened lower size Middle Fork-Virginia clean coal sample* using air pressures at 2000 G-Force

Cake Moisture Content (%)

Air Pressure (kPa) Spin Time (sec)

No Air 100 200 300 350

0 47.9 47.9 47.9 47.9 47.9 30 40.3 36.5 33.7 29.6 27.3 60 39.9 35.9 31.1 26.0 25.1 90 39.8 35.5 30.3 24.1 23.1 120 39.7 35.0 29.5 23.6 22.4 150 39.7 34.6 28.9 22.9 21.6


288

APPENDIX H FLOTATION TEST DATA

Table 1-H Test results on flotation of Red River Taggart seam coal sample

Stream % Ash (DB) Yield (%) Comb. Recovery (%)

Product 3.94 Tails 91.50 Feed 26.58

74.14 97.01


75.35 97.61


74.72 96.75

* Particle size 65 mesh x 0; thickener feed sample floated using 1 lb/ton diesel and 100 g/ton PPG.

Table 2-H Test results on flotation of Red River Dorchester seam coal sample

Stream % Ash (DB) Yield (%) Comb. Recovery (%)


61.92 91.47


63.00 92.84


63.46 92.94

* Particle size 65 mesh x 0; thickener feed sample floated using 0.25 lb/ton diesel and 100 g/ton PPG.

289

APPENDIX I: MICROSCOPIC POPULATION BALANCE MODEL OF THE NOVEL

CENTRIFUGE FOR THE FINE PARTICLE SETTLING

The purpose of the model is to understand the mechanisms of the novel dewatering centrifuge

underlying the particles settling on the filter media of the basket. The settling of the particles is

an important parameter in determining the final moisture content of the product. In order to

model the system, Microscopic Population Balance Model is selected for the mathematical

description of the process developed for the dewatering of the fine particles. Figure 1 shows the

cross-sectional area of the centrifugal filter.

Suspension

z y

x

Directions

Figure 1 The cross-sectional area of the centrifugal basket

Model Description:

The general formula of the microscopic population balance model is given below [1-3]:

ddt

ddx

Vddy

Vddz

Vd

dvj D Ax y z

jj

JΨΨ Ψ Ψ+ + + + + − =

=

− −∑( ) ( ) ( ) ( )ψ

ς10 [1]

I II III IV V VI VII

Assumptions:

1) The settling of the particles acts as a batch operation, where Qin = Qout = 0

2) The fine size D of the spherical particles is characteristics of interests for the settling on the

filter media to form a cake.

G-force r0 Air Pressure r

290

3) According to the Stokes` law, the velocity Vs of the particles in a settling tank is dependent

on several parameters:

Vs = η

ρ18

2 gD∆ [2]

at which ∆ρ is the deference in density between solid ρs and liquid ρl, D is the particle

diameter, g is the gravitational constant and η is the absolute viscosity of liquid. For the

centrifugal field applied in the basket, the gravitational acceleration value is substituted by

ω2r. Thus, the formula written for the velocity of the particles will be:

Vs = ηωρ

18

22 rD∆ [3]

In the novel centrifuge, one other parameter, which is air pressure acts on the particles during

the settling. As a result, the same equation may be expressed as below:

Vs = η

ωρ18

)( 22 arD +∆ [4]

at which ω is the angular velocity of the basket, r is the distance from center of rotation and a

is the air pressure in the basket in the form of acceleration.

4) The system volume does not change with time.

5) Initially, the particles are well dispersed in the slurry.

6) There is no sudden appearance and disappearance in the system.

7) The transportation of the particles is by the action of the settling.

8) The centrifuge is considered plug-flow in x direction and fully mixed in y and z directions in

this model.

9) Vx (or Vs) is not a function of height, but it is of particle size.

Terms:

Term I =dt

dψ Assumption 1

Term II = )( Ψxx

Vdd = )(

xx d

dV ψ Assumptions 2, 3, 7, 8 and 9

Term III = 0 Assumptions 3 and 8

Term IV = 0 Assumptions 3 and 8

291

Term V = 0 Assumptions 4 and 5

Term VI =0 Assumption 6

Term VII = 0 Assumption 6

From these assumptions, the model equation of the novel dewatering unit for the number

concentration/volume can be:

dtdψ + )(

xx d

dV ψ = 0 [5]

where Ψ is the population characteristics (in this case particle concentration in a time), Vx ( or

t

x

dd ) is the settling velocity of the particles (same as Vs), and t is the settling time. In order to

convert the equation into mass/volume, it is necessary to multiply the entire equation by kvD3ρs,

where kv is the shape factor. Therefore, for the fine particle settling of the novel centrifuge, one

can write the following equation.

(dt

d tD ),(ψ+

ηωρ

18)( 22 arD +∆ )( ),(

x

tD

ddψ

)kvD3ρs = 0 [6]

Boundary and Initial Conditions:

At t = 0, initially solid concentration in the x direction of the centrifuge is the same,

which means that all particles are in suspension.

At the end of the settling, all particles are settled on the surface of the filter media.

Therefore, the solid concentration in the liquid is zero.

Discretization:

Discretization of the model could be made to obtain a proper format:

dt

d tD ),(ψ kvD3ρs +

ηωρ

18)( 22 arD +∆ )( ),(

x

tD

ddψ

kvD3ρs = 0

Rearranging the equation,

292

dt

d tD ),(ψ kvD3ρs = -

ηωρ

18)( 22 arD +∆ )( ),(

x

tD

ddψ

kvD3ρs

If ψ = nf(m,D), and ψ kvD3ρs = f(m,D) (D, t), the equation can be:

),(),( tDfdd

Dmt

= -Vx ),(),( tDfdd

Dmx

[7]

where n is the number of particles per unit volume of the slurry in the basket at time t, f(m, D) is

the number fraction of the particles between k and k+1 at position x and time t and m is the mass.

By integrating the left side of the Equation [7];

∫+

k

kDm dDtDf

dtd

1),( ),( = ∫

+

k

kDm dDtDf

dtd

1),( ),( =

),,(

^

kDmfdtd [8]

For the right side of Equation [7];

∫+

−k

kDmx dDtDf

dxdV

1),( ),( = - ∫

+

k

kDmx dDtDf

dxdV

1),( ),( =-Vx

),,(

^

kDmfdxd [9]

Combining the Equations [8] and [9], the microscopic population balance model of the

novel centrifugal for the settling of the fine particles can be below:

),,(

^

kDmfdtd = -Vx

),,(

^

kDmfdxd [10]

According to this equation, the fine particle concentration in the suspension can be

determined as a function of time. It is expected in this model that the gravitational effects of the

novel unit on the fine particles are thousands of times greater than the sedimentation column that

acts only 9.81 m/s2 on the particles. More detail studies will be conducted on this model and

published elsewhere in the future.

REFERANCES

1. Adel, G.T., `MinE 5094 Notes: Particulate Process Modeling`, Spring 1998,

293

2. L.G. Austin; R.R. Klimpel and P.T. Luckie, (1984) `Process Engineering of Size

Reduction: Ball Mill`, Society of Mining Engineering-AIME, USA

3. W.Z. Choi, G.T. Adel and R.H. Yoon, (1985),`Liberation Analysis Using a Simple Image

Processing System`, 16th Annual Meeting of the Fine Particle Society, Volume III, Miami

Beach.

4. C.M., Ambler, `The Evaluation of Centrifuge Performance`, Chemical Engineering Process,

March, 1952, Vol. 48, No. 3, pp. 150-158

5. Svarovsky, B., `Solid-liquid Separation, Second Edition`, London, 1991

6. J. Bear; M.Y. Corapcioglu, and J. Balakrishna, (1984).`Modeling of Centrifugal Filtration

in Unsaturated Deformable Porous Media`, Advance in Water Resource`, pp.150-167

7. A. Rushton, (1981), `Centrifugal, Filtration, Dewatering and Washing`, Filtration and

Separation, September/October, pp.411-415

8. M.Y. Corapcioglu, and J. Balakrishna, (1985), `Steady State Centrifugal Cake Filtration`,

Filtration and Separation, November/December, pp.381-386

9. D.A. Dahlistrom, (1985), `Filtration`, (Thickening, Filtering, Drying), SME, Mineral

Processing Handbook, Volume 1, pp.(9-14)-(9.27)

10. R.H. Perry; D.W. Green; J.O. Malony, (1996), `Liquid-Solid Systems, Centrifuges`,

Perry`s Chemical Engineering Handbook, Sixth Edition, pp.19

294

APPENDIX J: THE CAPILLARY PRESSURE CHANGE AS A FUNCTION OF

VARIABLES

A simple computer program on the capillary pressure change as a function of the variables has

been developed in Mathematica and given below:

rp θγ cos2 23= Laplace Equation

Condition 1:

r: 1 µm

p1=plot3D[2γCos[πθ/180]/1, {γ, 5, 75}, {θ, 0, 110}, FaceGrids→All,

viewpoint -> {2.792, 1.714, 0.854}, AxesLabel→ {``γ [mN/m]``, ``θ [°]``, ``p [kPa]``}];

Condition 2:

r: 3 µm

p2=plot3D[2γCos[πθ/180]/3, {γ, 5, 75}, {θ, 0, 110}, FaceGrids →All,

viewpoint -> {2.792, 1.714, 0.854}, AxesLabel → {``γ [mN/m]``, ``θ [°]``, ``p [kPa]``}];

295

Condition 3:

r: 9 µm

p3=plot3D[2γCos[πθ/180]/9, {γ, 5, 75}, {θ, 0, 110}, FaceGrids →All,

viewpoint -> {2.792, 1.714, 0.854}, AxesLabel → {``γ [mN/m]``, ``θ [°]``, ``p [kPa]``}];

296

p = show [p1, p2, p3, viewpoint -> {2.845, 1.081, 1.479}];

As can be seen from the later figure, the capillary pressure is strongly dependent on the contact

angle of the surface, which is why the present investigations were focused on for the fine

particle dewatering.

appendices appendix a dewatering aid tests - pure …

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