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•Case Study: First Municipal-Industrial Water Reuse Project In Virginia!

Hampton Roads Sanitation District (HRSD) was created in 1940 to reduce pollution in the Chesapeake Bay. It currently serves a population of approximately 1.6 million with nine regional wastewater treatment plants in Hampton Roads and four smaller plants on Virginia's Middle Peninsula. HRSD set the goal to reuse its treated wastewater for nonpotable purposes in the 1980s. An oil refinery located next to their York River Treatment Plant (YRTP) approached HRSD in 1996 to supply reclaimed water for the refinery's cooling and process water. Previously, the refinery utilized increasingly expensive potable water and upgrading its own treatment facilities was too large an investment. In December 2000, HRSD signed a 20-year agreement to provide the refinery with 0.5 MGD of reclaimed water. This was Virginia's first municpal-industrial water reuse project!

Since the existing activated sludge treatment process at HRSD's York River Treatment Plant couldn't reliably meet the refinery's special target requirements for both low turbidity and year-round ammonia concentration, other treatment processes had to be investigated. HRSD first investigated filtration technologies for enhanced solids removal. Following a pilot study in 1998, they installed a 4-disk AquaDisk® cloth media filter. HRSD chose the AquaDisk® cloth media filter over a sand media filter because of its footprint and operational advantages. HRSD then researched several secondary treatment processes and decided to install a single basin AquaSBR® system fed with primary clarifier effluent to produce year-round biological nitrification. The AquaSBR® system was chosen for its reliablilty and cost-effectiveness. The reclamation operation began in July 2002 and the reclaimed water quality has always been better than originally required. The reclaimed water system is designed so that fully treated water can be fed to the AquaDisk® filter from either the full-scale plant effluent or the sidestream AquaSBR® system.

HRSD sells the reclaimed water to the refinery at cost, to recover only the additional investment of building and operating the sidestream treatment and the filter. The total cost of the reclaimed water over the 20-year agreement period is approximately half that of potable water. Not only does this reuse partnership save the refinery money and provide a drought-proof water source, it also conserves natural resources and reduces nutrients otherwise released into the York River, and ultimately into the Chesapeake Bay. The partnership has also led to the receipt of two awards: the WateReuse Association's national "Project of the Year" (2003) and "Honors Award for Engineering Excellence" (2004) from the American Council of Engineering Companies of North Carolina.

HRSD is pursuing other uses of reclaimed water which may lead to reuse projects at its other treatment facilities in the future. The possibilities include: boiler feed water, tunnel washing, and irrigation, to name a few.

Click Here To Download:
•Case Study: First Municipal-Industrial Water Reuse Project In Virginia!