| (19) |
 |
|
(11) |
EP 0 006 065 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
23.01.1980 Bulletin 1980/02 |
| (43) |
Date of publication A2: |
|
12.12.1979 Bulletin 1979/25 |
| (22) |
Date of filing: 01.06.1979 |
|
|
| (84) |
Designated Contracting States: |
|
AT BE CH DE FR GB IT LU NL SE |
| (30) |
Priority: |
05.06.1978 US 912616
|
| (71) |
Applicant: CALGON CORPORATION |
|
() |
|
| (72) |
Inventor: |
|
- Ralston, Paul Hotchkiss
()
|
|
| |
|
| (54) |
Composition and method for inhibiting corrosion |
(57) A corrosion inhibitor composition and a method for its use in potable and industrial
water treatment facilities for controlling corrosion encountered in water distribution
systems such as turbine pump blades, the main distribution piping, their tributaries,
and domestic and industrial piping comprises a weight ratio of PO
4= to Zn
*of about 2:1 to 3:1. When added to the raw water intake or other suitable point in
small but effective quantities, it passivates metal surfaces. The inhibitor is effective
within a pH range of about 5-9 but is especially effective in waters having a pH of
6.5-8.