CONVERSION AND OPERATION OF THE COMMERCIAL UMM LUJJ SWRO PLANT FROM A SINGLE SWRO DESALINATION PROCESS TO THE NEW DUAL NF-

Earlier pioneering work done at SWCC RDC on the pilot and demonstration plants level demonstrated that the NF pretreatment of seawater feed to seawater desalination plants: (1) prevented SWRO membrane fouling by the removal of turbidity and bacteria, (2) prevented plants scaling (both SWRO and MSF) by removal of scale forming hardness ions and (3) lowered required pressure to operate SWRO plant by reducing TDS of seawater feed. The net effect of this NF pretreatment was to increase SWRO potable water yield and recovery. Likewise, it increased MSF distillate recovery and it allowed for the operation of SWRO and MSF without the addition of antiscalant and antifoam. It also allowed for the operation of the latter also without scale formation, at MSF top brine temperature (TBT) of ≥120oC. To evaluate this new NF-SWRO desalination process on a commercial plant scale, one SWRO Train 100, capacity 2203 m3/d (582,085 gpd) at the existing Umm Lujj SWRO plant, which was commissioned in 1986, was converted from a single SWRO desalination process to the new dual NF-SWRO desalination process by the introduction of an NF pretreatment and semidesalination unit ahead of the existing SWRO unit. The second Line, Train 200, at the same plant, which is identical in desig