The authors provide the results of a study investigating
factors affecting biofilm accumulation in
bench-scale distribution systems using both synthetic
and real waters. The effects were assessed by
measuring the accumulation of heterotrophic plate
count bacteria per unit area in an annular reactor. The
results showed that the disinfectant residual was the
most important factor in terms of controlling biofilm.
The highest biofilm levels were observed under conditions
in which a high level of easily biodegradable
organic matter was present and there was no disinfectant
residual.
Although a number of investigations have been
conducted to examine the formation of biofilms in both
real and model distribution systems, there is relatively
limited information from controlled experiments that
have systematically investigated the various factors
influencing the extent of biofilm formation. The
authors' purpose in conducting this research was to
quantify the effects of the following factors: chlorine or
monochloramine residual, concentration of easily
biodegradable organic matter, shear (i.e., flow velocity),
pipe material, and temperature.
The results of this investigation have important
practical implications for control of biofilms in distribution
systems. North American practice is generally to
maintain a residual in the distribution system, in part
for biofilm control. However, the results of this study
suggest that the residual should be defined based on a
variety of factors and that interactions among the various
factors are important in determining the extent of
distribution system biofilm accumulation. Includes 29 references, tables, figures.
| Edition : | Vol. 95 - No. 1 |
| File Size : | 1
file
, 210 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 01/01/2003 |
