 |
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|||||||||||
 |
 |
 |
|
|||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
|
|||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
 |
 |
|
||||||||||
 |
|
|||||||||||
Pollution Prevention and Control Technologies for Plating Operations
Section 3 - Chemical Recovery
3.6 ELECTRODIALYSIS
3.6.7 Operational and Maintenance Problems
Only one of the two survey respondents who used this technology provided any information on O&M problems. PS 012 provided the following statement:
"Lack of availability of replacement membranes and long repair time by factory after membrane failure (1 year and up to 6 months down) coupled with high repair cost for each failure ($6,000) made this a non-viable technology, was abandoned circa 1987."
As with most membrane technologies, the life span of the membrane is a key concern to the system owner. One vendor provided estimates of membrane life span during the Vendors Survey. Kinetic Recovery Corporation estimated that their membranes (OS-FD/FS types) last three to seven years for all recovery applications. The Graver Company provided the following estimates for membranes, gaskets and electrodes for acid and alkali recovery (i.e., from concentrated baths, not rinse water).
Acid Recovery Alkali Recovery Membranes 0.5 to 1.0 yr 0.3 to 1.0 yr Gaskets 1 to 2 yr 1 to 2 years Electrodes 2 to 4 yr 2 to 4 yearsThe Graver Company further indicated that the longevity of membrane life was dependent largely on the level of contaminants present.