Three Center Configuration

Intended for very large SWRO systems such as the Ashkelon system, this configuration organizes the equipment into three groups; a HP pumping center, a membrane center, and an energy recovery center. Each center is connected by pipe manifolds. The number of operating equipment items in each center can be varied as required or capacity management and maintenance. Most typically, the HP pump center pressurizes a feed flow equal to the permeate output requirement. The remaining feed flow pressurization is provided by the ERD center.

The ERD center may use either isobaric chambers or FEDCO HPB's. HPB's add greatly to operational simplicity and economic advantage of the three center arrangement by:

• Elimination of brine intrusion into the feed stream thereby reducing required feed pressure and improving permeate quality
• Vastly lower capital and installation costs
• Much simpler control scheme; much easier to startup and shutdown
• Much easier to adjust production rates
• Ability to vary feed pressurization and flow in ERD section adds new degrees of freedom in plant operation

The figure below illustrates the full three-center configuration for a mega-scale system:

The figure below illustrates the ERD portion of the three-center configuration for a mega-scale system.