AWWA ACE92169

Diffusion controlled membrane processes such as reverse osmosis (RO) and nanofiltration (NF) have been considered as water treatment processes that produced corrosive finished waters. These processes and the treatment processes associated with conventional RO and NF treatment systems typically remove too much calcium and alkalinity to provide a buffered and easily stabilized finished water. Microfiltration (MF) and ultrafiltration (UF) processes do not produce corrosive waters because they do not remove any dissolved alkalinity or calcium and therefore do not directly affect the finished water buffering or stabilization. However the stabilization pH with respect to calcium carbonate, pHs, is usually above 9 and carbonate alkalinities are typically less than 20 mg/L as CaCO3 for conventionally produced RO finished waters. The loss of alkalinity from diffusion controlled membrane processes can be controlled by a modification of the conventional membrane process. This paper describes a field investigation of lead, copper and galvanized steel corrosion rates from a modified membrane process and a conventional groundwater treatment process at Pinellas County Florida.

Product Details

Published:

01/01/1992

ISBN(s):

0898676525

Number of Pages:

8

File Size:

1 file , 320 KB