1. Versatility of “Vacuum Bag Dewatering ”(pat pend) of Dredged Organic Silt
Roger G. Miller, P.E., President
Miller Engineers & Scientists
Sheboygan, Wisconsin, USA

2. Geotube® Gravity Dewatering

3. Organic Silt after three months in Geotube®
Moisture Content = *120%
Liquid Limit = *140%
Plasticity Index = *80%
Percent Sand and Gravel = *35%
Su/Pp ~ *Dry Wt Basis

4. Vacuum Bag Prototype Test (2008)
Clear Water Discharge

5. Vacuum Bag System

6. Mechanical Filter Plate Presses, LFR 2009

7. Sediment “Cake” after Dewatering

9. Drainage Layer Thickness vs. Time
Organic Silt Layer
Thickness Feet (m)
Time To
Consolidate (Days)
1 (0.3)
2 ½
2 (0.6) 10
3 (0.9) 23
4 (1.2) 41
Time for dewatering is proportional to the square of the height of the material.
Temperature vs. Time
Material Temperature
Degrees F 34 50 59 68 77 86 95
104
113
(Degrees C)
(5)
(10)
(15)
(20)
(25)
(30)
(35)
(40)
(45)
Time Adjustment Factor
1.52
1.31
1.14
1.00
0.89
0.80
0.72
0.65
0.60
Increasing material temperature shortens consolidation time by lowering the viscosity of the pore water.

10. Vacuum Bag Consolidation of Geotubes®

11. Vacuum Bag Dewatering in Barge

12. Vacuum Bag Dewatering of Sedimentation Basin

13. Reef Building or Deep Water Disposal

14. Sediment Vacuum Bag Dewatering in the Lab

15. Contact Information:
Roger G. Miller, PE, President
Miller Engineers & Scientists
5308 South 12th Street
Sheboygan, WI
Phone (800)
US Patent 7,454,847 B1 issued and
general concept patent pending.