Process for the improved working up of effluent

• US 4,287,069 A
• Filed: 05/05/1980
• Issued: 09/01/1981
• Est. Priority Date: 05/21/1979
• Status: Expired due to Term

• Current Assignee: Bayer AG
• Original Assignee: Bayer AG
• Inventors: Sahlmen, Friedhelm, Reischl, Artur, Mack, Kurt
• Primary Examiner(s): Wyse, Thomas G.
• Application Number:
  US06/146,919
• Time in Patent Office: 484 Days
• Field of Search: 210/609, 210/631, 210/730, 210/735, 210/919, 210/714
• US Class Current: 210/609
• CPC Class Codes: C02F 1/54 using organic material
• CPC Class Codes: C02F 11/12 by de-watering, drying or thickening
• CPC Class Codes: Y10S 210/919 using combined systems by merging parallel diverse waste systems

Abstract

The instant invention is directed to a process for the separation of aqueous sludges in the purification of effluents in purification plants, comprising:

(a) mixing organic and/or inorganic aqueous sludges with ground monomer-free tolylene diisocyanate (TDI) distillation residues having a mean particle size of less than 2 mm;

(b) removing the water from the resulting purified sludges; and

(c) disposing of the purified sludges.

Claims

1. A process for the separation of aqueous sludges in the purification of effluents in purification plants, comprising:

(a) mixing organic and/or inorganic aqueous sludges with ground monomer-free tolylene diisocyanate (TDI) distillation residues having a mean particle size of less than 2 mm;

(b) removing the water from the resulting purified sludges; and

(c) disposing of the purified sludges.

2. The process of claim 1, wherein said TDI distillation residues have been prereacted with isocyanate-reactive compounds.

3. The process of claim 1, wherein said ground TDI distillation residues have a mean particle size of 1 mm or less.

4. The process of claim 3, wherein said ground TDI distillation residues have a mean particle size of 0.03 to 0.8 mm.

5. The process of claim 1, wherein said TDI distillation residues are denatured by adding to water with a temperature above 130°

C.

6. The process of claim 1, wherein the isocyanate groups of said TDI distillation residues are completely reacted with water and/or isocyanate-reactive compounds.

7. The process of claim 1, wherein said TDI distillation residues contain cationic and/or anionic groups.

8. The process of claim 1, wherein said TDI distillation residues are added in a quantity of from 10 to 80% by weight, based on the total solids.

9. The process of claim 1, wherein said TDI distillation residues are mixed with said aqueous sludges in an activated sludge tank.