Process for conditioning soft water to become drinking water

US5695646A · kind A · utility

Assignee

• Passavant-Werke AG · DE

Inventor

• Franz Graf · Burghausen, DE

Key dates

• Filing date: Dec 5, 1995
• Grant date: Dec 9, 1997
• Expiry date: Dec 5, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C02F2303/08
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

In connection with processes for conditioning soft water (pH less than/equal to 6) to become drinking water, it is necessary to supply hardening agents in order to raise the carbonate-dissolving pH value into the neutral range. Subsequently the turbid materials are flocculated out and the flocculation products are filtered off. Finally, the calcite equilibrium must be set by means of a renewed addition of a hardening agent. This process is simplified by means of the invention in that the calcite equilibrium by means of the supply of highly pure lime water is only set after filtering off the flocculation products. In the flocculation stage, highly pure lime water is also preferably employed for setting the flocculation pH value.