278
H. S. Weinberg
3 Contaminants in the Treatment Process
The conventional process for turning surface water supplies into drinking water is
illustrated in Fig. 1.
Disinfectant I Oxidant
RAW
WATER
Disinfectant
' ·""1-'
~---~
Cleanvell
Flash Mix
Filter
1 - - - -.... DISTRIBUTION SYSTEM
Fig. 1. Conventional treatment (italicized steps are optional)
3.1 Treatment Chemicals
Sludge
Among the chemicals utilized in this process, pH adjusters and softeners rank
among the most frequent, followed by coagulants and flocculants (Peaff 1994).
While there are only anecdotal reports of trace metal accumulations resulting from
the use of sulfuric acid, the levels of heavy metals associated with alum use have
been documented (Bishop et al. 1987). In the case of alum, bauxite, which
contains many metal constituents, is the major starting material. The commercial
grade product, which typically contains more than 50 g rl aluminum does not
actually pass through the most intensive cleanup procedures and can impart elevated
H. S. Weinberg
3 Contaminants in the Treatment Process
The conventional process for turning surface water supplies into drinking water is
illustrated in Fig. 1.
Disinfectant I Oxidant
RAW
WATER
Disinfectant
' ·""1-'
~---~
Cleanvell
Flash Mix
Filter
1 - - - -.... DISTRIBUTION SYSTEM
Fig. 1. Conventional treatment (italicized steps are optional)
3.1 Treatment Chemicals
Sludge
Among the chemicals utilized in this process, pH adjusters and softeners rank
among the most frequent, followed by coagulants and flocculants (Peaff 1994).
While there are only anecdotal reports of trace metal accumulations resulting from
the use of sulfuric acid, the levels of heavy metals associated with alum use have
been documented (Bishop et al. 1987). In the case of alum, bauxite, which
contains many metal constituents, is the major starting material. The commercial
grade product, which typically contains more than 50 g rl aluminum does not
actually pass through the most intensive cleanup procedures and can impart elevated