Patent · US Expired

Cleaning and disposal of carbon black and ash containing wastewaters

US4828715A · kind A · utility

6Cited by

2References

7Claims

0Family size

Assignee

BASF SE

Inventors

Bruno Sander · Ludwigshafen, DE
Siegfried Marquardt · Frankenthal (Pfalz), DE
Gero Lueth · Mannheim, DE
Robert K. Horn · Ludwigshafen, DE
Uwe Kempe · Schifferstadt, DE

Key dates

Filing date	Mar 21, 1988
Grant date	May 9, 1989
Priority date	—
Expiry date	Mar 21, 2008

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S210/912
WIPO fieldEnvironmental technology
WIPO sectorChemistry

Abstract

Carbon black and ash containing wastewaters from high-temperature processes in which the carbon black is present in an extremely finely divided and partly colloidal state are cleaned and disposed of by treatment with organic flocculants, predewatering of the flocculated suspension by gravity filtration and post-dewatering of the carbon black sludge by pressure filtration within the range from 0.5 to 15 bar in a process comprising adding sufficient calcium hydroxide to the wastewaters that the pH of an aqueous extract of the filter cake obtained is more than 11.8, preferably more than 12.0.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.