In late 2005, the Racine Water Utility successfully commissioned operation of a 50 MGD
immersed ultrafiltration (UF) membrane plant. As utility staff and other stakeholders gained
experience and insight into the operation of this completely new treatment process, various
opportunities to improve on the installed system and on the proposed operation procedures
became apparent and necessary. These improvements have reduced membrane fouling, reduced
chemical cleaning costs, reduced energy costs and have increased treatment capacity. This paper
presents the results of the on-going improvements to the Racine UF facilities.
During 2008, Racine staff conducted a full-scale testing program to evaluate the impact of
converting the pretreatment coagulant from ferric sulfate to polyaluminum chloride to reduce iron
fouling of the membranes. Testing results demonstrated a significant improvement in membrane
permeability, reduced trans-membrane pressure, lowered permeate pump energy use, and
lengthened chemical clean-in-place intervals.
Full-scale testing over several months also supported decreasing the frequency for membrane
chlorine maintenance cleans from daily to weekly with no impact to the membrane performance.
This modification has reduced sodium hypochlorite chemical costs by nearly 50% and increased
daily production time and net permeate capacity for the system.
Both the membrane supplier and utility staff made physical modifications to the commissioned
membrane system during the first two years of operation to substantially improve operations.
Modifications to the vacuum prime system has reduced the time required to perform the State
required 3/day integrity testing, thereby increasing the daily net production time for each
membrane train by close to 1 hour. In addition, revamping of the permeate vacuum system
lowered electrical costs and reduced preventative maintenance activities and costs. Other
changes to standard operating procedures and PLC programming have lowered fouling rates and
reduced system alarms and warnings. Includes figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 940 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 9 |
| Published : | 11/01/2009 |
