Membrane and Desalination Technologies - TCE Moodle Website

Treatment of Industrial Effluents, Municipal Wastes, and Potable Water 229
commercially available (65), and its process descriptions and historical development can be
found in the literature (1, 2, 51–54, 66).
7.9. Membrane Bioreactor Design
Copeland et al. (64) have addressed the fundamental design requirements needed for the
MBR WWT system’s compliance with the regulated effluent limits. They (64) discussed
technical issues that were accounted for in the process analysis and biological modeling as a
means to help evaluate the design criteria. Their information (64) should help engineers,
regulatory agencies, and owners address the minimum requirements for initiating an MBR
WWTP. More design considerations of MBR systems can be found in the literature (54, 69,
81–83).
7.10. Using Flotation as a Pretreatment to Membrane Processes
The need for fresh sources of high-quality drinking water or reclaimed water is becoming
more and more urgent worldwide. All membrane processes (including MBR), on the contrary,
are known to be very sensitive to foulants as colloids, inorganic scale, and biofouling.
Pretreatment of their membrane reactor’s feed water is often a key step. In membrane plants
design, various techniques have been proposed for pretreatment, even other membrane
filtrations such as ultrafiltration. However, DAF is highly efficient for removing oil, grease,
and suspended solids, such as activated sludge or algae (66, 67).
7.11. Full-Scale Membrane Bioreactor Technology for Water Reclamation
GE Water & Process Technologies, a unit of General Electric Co. (68), is supplying its
ZeeWeed MBR ultrafiltration technology as part of a $250 million upgrade and expansion to
the Yellow River Water Reclamation Facility (WRF) in Gwinnett County, GA. The selection
of the advanced ZeeWeed treatment process contributed to a $50 million savings in the
projects capital costs, largely due to the compact size of the ZeeWeed MBR system, which
helped to reduce the quantity of concrete, steel, and labor needed to complete the construction
dramatically.
GE’s ZeeWeed MBR process eliminates the need for large, costly concrete settling tanks
that conventional wastewater processes rely on to separate contaminants from treated effluent –
instead occupying just a fraction of the space to consistently produce tertiary-quality effluent
that can be safely discharged to sensitive receiving bodies or reused for various, nonpotable
applications (76–79, 81).
In April 2004, the Couley Creek Water Reuse Facility was commissioned (76). This
ZeeWeed MBR plant was the first of its kind in the State of Georgia and was designed to
treat an average day wastewater flow of 5 MGD (18,893 m 3 /d). The plant incorporated the
following upgrades: optimized biological phosphorus removal to minimize chemical consumption,
mixed liquor surface wasting to minimize scum and foam in the aerobic zones, and
a sludge thickener to minimize the aerobic digester volume. The treated effluent from the
reuse facility surpasses tertiary effluent standards and is provided to local golf courses, sub-