Date of Award
Bachelor of Science
Paper Science and Engineering
Dr. David Peterson
The waste, or sludge, from a mill contains a significant amount of water. It is desirable to remove as much water as possible before the sludge goes to a landfill. In the past electrokinetics have been used to separate solids and liquids in the mining and clay industries. The objective of this thesis project was to determine if the application of electrokinetics can increase the drainage rate of sludge by transmitting an electric current through the sludge. On a larger scope, this application may be used in addition to another process for increased efficiency.
The experiment contained sludge placed between two charged metal screens. The drainage was measured and compared to a control run with no voltage applied to the screens. The results demonstrated that applying en electric field to sludge increased the drainage rate. The increased drainage was due to electro-osmotic forces, which forced the water out of the electrode carrying water molecules with them. The pH of the filtrate was tested and found to change either acidic or basic, depending on the arrangement of the electrodes, which indicated chemical reactions were occurring.
In conclusion, the application of electrokinetics increases sludge dewatering. I recommend further investigation into the possibilities of applying this concept to another pressing or filtering process which would result in a more efficient process. The drastic change in pH opened other areas for study, as electrokinetics can be used to remove or direct chemical contaminants.
Donnelly, Maureen, "The Application of Electrokinetics to Improve Sludge Dewatering" (1994). Paper Engineering Senior Theses. 115.