Analytical methods and equipment were developed to correlate membrane fouling
with feedwater quality parameters under controlled operating conditions. A self-contained,
portable bench-scale reverse osmosis (RO) test unit was fabricated and installed at
locations with source waters including surface water, lime-clarified and
microfiltered secondary treated wastewater, tertiary treated wastewater, brackish
groundwater and agricultural drainage water. Four commercially available
membranes were tested: three polyamide membranes and one cellulose acetate
membrane. Membranes were operated in a single-pass configuration, each at a
constant flux of 10 gfd and 4 percent recovery. Typical duration of each run was
10 to 12 weeks or until the feed pressure to any polyamide membrane exceeded
200 psi. Membrane operating parameters (transmembrane pressure, water flux
and solute rejection) were measured daily and water quality grab samples were
collected weekly. Water quality analyses included general minerals, microbial
analysis by heterotrophic plate counts and epifluorescence microscopy,
community analysis by 16S rRNA and particle size analysis. At the end of each
test, membranes were autopsied to determine both the physiochemical properties
(ATR/FTIR spectrometry, zeta potential, particle size analysis and scanning
electron microscopy) of the membrane and the nature of the biological material
accumulated on the membrane surface (protein, carbohydrate, microbiological
analysis by heterotrophic plate counts and epifluorescence microscopy,
community analysis by 16S rRNA). Collected data were compiled in a database.
Chemical, physical, and biological characteristics of the source waters,
membranes and fouling layers were measured and used to develop relationships
between source water quality, membrane composition, and membrane fouling
using conventional multivariate analysis and artificial neural net analysis. Includes abstract only.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 190 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 2 |
| Published : | 11/15/2004 |
