In 1994 and 2001, US water providers were surveyed about
their use of phosphate inhibitors. Responses pointed to
widespread use of phosphate inhibitors, including polyphosphate,
orthophosphate, zinc orthophosphate, and phosphate
blends. From 1994 to 2001, a number of respondents shifted from
poly/orthophosphate blends to orthophosphate, a trend viewed as
beneficial because polyphosphate compounds have been shown
to be detrimental to metal corrosion under some circumstances.
Although many water suppliers used phosphate inhibitors, few
conducted any scientific tests to determine the applicability of
inhibitors to their particular circumstances. In selecting a phosphate
inhibitor, most utilities relied on vendor data or reports of
chemical success at another facility. Even at larger utilities, where
managers were aware of potential drawbacks of inhibitors, many
did not know the exact composition of the phosphate chemicals
they were using.
Survey results indicate that many utilities are incurring considerable
costs to add inhibitors without direct proof of the chemical's
efficacy in their particular water. Understanding how and why
inhibitors are used is the first step toward helping utilities develop
effective strategies to meet the diverse goals of corrosion control
and water quality. More support is also needed to help utilities
make informed decisions about inhibitor use. Water providers need
to look at their phosphate inhibitor use, examine their reasons for
using phosphates, and base their phosphate selection on hard data
and their individual water conditions.
Includes 44 references, tables, figures.
| Edition : | Vol. 94 - No. 7 |
| File Size : | 1
file
, 230 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 7 |
| Published : | 07/01/2002 |
