Recent Development in Organic Sludge Dewatering Technique

목차 (Table of Contents)

• 1. Kinds of cationic polyelectrolyte
• 2. Action of cationic polyelectrolyte
• (1) The larger the molucular weight of a cationic polyelectrolyte, the larger and stronger the flocs which are formed.
• (2) A cationic polyelectrolyte with higher catkonic density is favorable to charge neutralization, but does not necessarily form stronger flocs.
• (3) Flocculation ability of a cationic polyelectrolyte is decreased when a sludge is accompanying fewer anionic susbtances(natural anionic water soluble polymer surrounding sludge particles).
• 3. Combination of cationic and anionic polyelectrolytes
• (1) can reduce sludge cake moisture content by 5% lower than the conventional method,
• (2) can increase dewatering capacity by 40%
• (3) can revocer SS at a high rate, and give good separation of sludge cake from filter cloth
• (4) has a wide range of optimum dosage of the polyelectrolytes, and
• (5) is not so much influenced by sludge properties, leading to a wide range of application and stable treatment.
• 4. Use of amphoteric polyelectrolyte
• (1) Influence of sludge properties is small, and stable performance can be obtained even with sludges hardly dewaterable by the conventional method.
• (2) Treatment capacity increases to 1.5-2.0 time that of the coneventional method.
• (3) Moisture content of sludge cake decreases by 2-4% compared with the conventional method.
• 5. Pelletizing method
• 6. Subjects for further studies