Parker AQUA DUO A455C-2800, Technical Manual

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membrane pressure vessels (array) . The membrane array is an arrangement of fiberglass pressure
vessels each containing RO membrane elements.
The pressurized feedwater flows along the membrane elements where reverse osmosis takes place. The
feedwater flow is divided into two streams - the high purity product stream (referred to as the
product)
and the increasingly concentrated reject stream (referred to as the reject).
3.8 PRODUCT MONITORING SYSTEM
The product water stream flows past a conductivity sensor, which provides a signal to the water
quality monitor. Depending on the concentration of total of dissolved solids (TDS) in the permeate
stream, the following occurs:
If permeate TDS is> 500 ppm, indicating poor quality water, a signal is sent to divert the product
water to the reject line.
If permeate TDS is<500 ppm, indicating good quality water, a signal is sent to divert the product
water to the product line.
In addition, there is a product water flow meter and transducer to allow the operator to determine
how much water is being made.
3.9 FRESH WATER FLUSH SYSTEM
This RO unit includes a freshwater flush system which provides a means for removing the sea
water from the RO system. By using the freshwater flush cartridge housing with carbon filter installed
and the automatic feed inlet valve the system will automatically freshwater flush upon system
shutdown. Complete information of the freshwater flush procedures can be found in Section 6.4.
3.10 HUMAN-MACHINE INTERFACE (HMI)
The HMI/Controller monitors and displays system health and conditions like permeate salinity,
temperature, pressure, and accumulated unit operating hours. It also provides operational mode
control of the system.