AWWA JAW56923

Orthophosphate and polyphosphates are widely used by drinking water utilities to reducelead, copper, and iron (Fe) release from distribution system materials and reduce visible Feprecipitation and related discolored water complaints. Bench-scale experiments wereconducted to evaluate the effect of orthophosphate and several polyphosphates on theproperties of Fe particles and suspensions derived from the oxygenation of Fe(II) at a singleoxygen concentration over a broad pH range. Results showed that polyphosphates andorthophosphate, to a lesser extent, reduced apparent color and turbidity of Fe suspensions,decreased particle size, made the zeta potential more negative, and increased Fe suspensionstability. A fixed-mass concentration of low-molecular-weight polyphosphate was moreeffective at reducing the particle size of Fe(III) solids than high-molecular-weightpolyphosphates. Includes 53 references, tables, figures.

Product Details

Edition:

Vol. 94 - No. 10

Published:

10/01/2002

Number of Pages:

13

File Size:

1 file , 380 KB