The effects of fiber length and aeration rate on permeate flux decline in tests of a single,
submerged hollow fiber at constant pressure are presented. Without aeration, the initial rate
of flux decline was greater for a longer fiber length (1 vs. 0.7 vs. 0.3 m) at a relatively low
feed concentration of bentonite particles (100 mg/L). However, the same pseudo-steady
state in permeate flux was observed for all three fiber lengths as fouling progressed. The
fouling rate was greatly reduced by aeration for all three fiber lengths. However, the effect
was larger as fiber length became shorter. It was concluded that aeration was not as
effective for removal of the fouling layer formed near the fiber outlet where the local flux is
highest for the longest fiber length. Permeate flux decline (without aeration) was over
predicted by using the specific cake resistance from a small-scale, flat sheet test in a
hollow-fiber model. The explanation may involve the effect of axial gradient of pressure
drop on local specific cake resistance for compressible cakes. Small-scale tests cannot
account for this axial dependency. Includes 8 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 580 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 06/17/2004 |
